Dissertations / Theses: 'Land fragmentation'

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Dirimanova, Violeta. "Economic effects of land fragmentation property rights, land markets and contracts in Bulgaria." Aachen Shaker, 2007. http://d-nb.info/988177374/04.

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Dirimanova, Violeta. "Economic effects of land fragmentation : property rights, land markets and contracts in Bulgaria /." Aachen : Shaker, 2008. http://www.gbv.de/dms/zbw/562087699.pdf.

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Miller, Crystelle Leigh. "The price-size relationship: analyzing fragmenation of rural land in Texas." Texas A&M University, 2006. http://hdl.handle.net/1969.1/4911.

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According to the USDA, Texas leads all other states in the loss of rural farming and ranching land. Most research on rural land value has been associated with trying to explain price per acre movements, yet few studies have analyzed the relationship of market factors such as size on the total purchase price. This research focused on the parcel size and price per acre relationship that exists for Texas rural lands. The objective of this research was to examine the relationship between size and price per acre of land parcels sold in Texas and to analyze the presence of fragmentation of agricultural lands. Data on Texas land sales of parcels greater than ten acres from 1965-2004 were used. The relationship between price per acre and parcel size was analyzed for Texas as a whole and for eight separate farmland regions. Each region was analyzed over eight time periods to test for changes in the land market for different periods. The results indicated a statistically significant inverse relationship between price per acre and parcel size which held in all eight regions and each of the eight five-year time periods. Personal income of the buyers had a greater influence on price per acre than net farm income. Fragmentation was verified by comparing percent of sales in eight categories of acres sold, ranging from 10 acres to over 1,280 acres. Over the time period 1966-2004, the percent of sales for smaller parcels, 21-40 acres, increased and for moderate size parcels, 81-320 acres, the percent of sales decreased. The increase in percent of sales for smaller parcels and the conversion of moderate size parcels of 81-320 acres into less than forty acre parcels, suggests that fragmentation has occurred. Furthermore, the percent of sales for parcels larger than 320 acres increased over the time period which mitigated the effects of fragmentation.

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Phillips, Helen Rachel Patricia. "Effects of land use and habitat fragmentation on local biodiversity." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/58205.

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Land use change is one of the greatest threats to biodiversity. Land-use change often results in fragmentation of the landscape, yet this aspect is rarely taken into account in models of how land use affects biodiversity. Additionally, previous biodiversity models have been restricted to large spatial scales, which may not be applicable for conservation practitioners. In this thesis I analyse datasets collated from multiple published studies of how local terrestrial biodiversity responds to human impacts. I start Chapter 2) by modelling how land use, specifically secondary vegetation and plantation forests, impacts tropical biodiversity. My results show that the biodiversity in each continent does respond differently to land use, an aspect that previous studies have not investigated. This difference is most likely due to the nature of the land use being different in each continent. In this first analysis, as is often the case, drivers of biodiversity change were focused on site-level environment, such as land use. Therefore, in Chapter 3 I investigate how the area of habitat surrounding a sampled area might influence the number and abundance of species within the sample. Theory suggests that within-sample species richness would increase with fragment area with an exponent between 0.07 and 0.20, which was found to be the case. Chapter 4 builds on the previous chapters in two ways. Firstly, it applies the previously used methods to create a biodiversity model of habitat change for a smaller area to inform decision making. Secondly, it specifically takes into account how local biodiversity responds to changes in fragment area. I estimated that the planned changes to the small urban area would result in a gain in overall biodiversity, most likely due to an increase is size and number of high diversity habitats. To consider these results at a landscape scale, my final chapter (Chapter 5) investigates how the wider context around a sampled site influences local biodiversity. By studying the impact on biodiversity across this range of spatial scales, I can ascertain the importance of taking these variables into account and determine the implications of my results for previous models of biodiversity. I found that landscape fragmentation, as well as local land use, was a necessary component of models of local biodiversity, and its inclusion greatly improved previous biodiversity models.

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Dirimanova, Violeta [Verfasser]. "Economic Effects of Land Fragmentation : Property Rights, Land Markets and Contracts in Bulgaria / Violeta Dirimanova." Aachen : Shaker, 2008. http://d-nb.info/1164342541/34.

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Lopez, Robert Daniel. "Land-cover change, fragmentation, and agriculture in southwest Puerto Rico 1982-2002 /." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0013702.

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Chambers, Brian Carolan. "Negotiating Denendeh : indigenous solidarity, federal land claims policy, and fragmentation of the Dene/Metis comprehensive land claim." Thesis, University of Cambridge, 1996. https://www.repository.cam.ac.uk/handle/1810/251590.

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Dawidson, Karin E. K. "Property fragmentation : Redistribution of land and housing during the Romanian democratisation process." Doctoral thesis, Uppsala University, Department of Social and Economic Geography, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4646.

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In the context of democratisation in the early 1990s, the governments in Central and East Europe (CEE) had to decide how to deal with property that had been confiscated under state socialism. Nationalised housing and collectivised land were to a varying extent returned to former owners and their heirs by means of restitution, as well as being distributed to other citizens who were in possession of the users’ rights to such properties.

This thesis examines the spatial impacts, in terms of ownership patterns, of the way the redistribution of nationalised housing and collectivised land has been dealt with politically and at the local level in post-socialist Romania. It also locates the Romanian property reforms in relation to those of the rest of CEE. The impact of political directives on the property redistribution is analysed in relation to both structural influences, such as democratisation and antecedent property regimes, and implementation patterns in varied place-contexts. The thesis demonstrates that restitution was stifled due to disagreements between leftist and rightist political blocs, with the latter arguing for restitution whilst their opponents wrote the first restitution laws. A re-privatisation law allowed for the public sale of nationalised housing to tenants and thereby blocked the implementation of a restitution law, thus constituting a dilemma for constitutional democracy. In liberal place-contexts in West Romania, these obstacles to housing restitution were in part avoided. By contrast, land restitution was most widespread in the east, a stronghold of the left. This was because the legislation gives priority to restitution in areas of this kind, where smaller land-holdings dominated prior to 1945. The left-wing government pursued an electoral strategy of distributing small properties to a large number of citizens, and to current users in particular. This resulted in a fragmentation of historical property.

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Dawidson, Karin. "Property fragmentation : redistribution of land and housing during the Romanian democratisation process /." Uppsala : Deptartment of Social and Economic Geography, Uppsala University, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4646.

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Sundqvist, Patrik, and Lisa Andersson. "A study of the impacts of land fragmentation on agricultural productivity in Northern Vietnam." Thesis, Uppsala University, Department of Economics, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7623.

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This study examines the relationship between land fragmentation and agricultural productivity in Vietnam, as well as the outcomes of land consolidation programs on productivity. Data from the Vietnam Household Living Standard Survey 2004 and data on the land consolidation process was used for the regression analysis. The results show weak correlations between fragmentation and productivity. Land fragmentation seems to be positively correlated to productivity due to more use of fertilizers and labour input. The communes that have consolidated their land are more productive, but this seems to be explained by initial differences in productivity. Our results suggest that there are no immidiate gains in land consolidation.

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Regan, John Joseph Jr. "Land Use Predictors Affecting Land Disturbance in Exurban Arivaca, Arizona." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/202972.

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Exurbanization is occurring where large tracts of land are being sold to developers. Typically these are ranches that are then divided into 40-acre parcels and sold by developers, avoiding subdivision regulations requiring paved streets, utilities and other amenities. The result is an unplanned subdivision with no infrastructure, and tax revenues that cannot offset the cost of providing it. Interviews with professional planners suggested there may be independent variables capable of predicting the amount of human disturbance in an exurban area: parcel size, full cash value, tenure, distance to paved roads, site-built housing, mobile homes, and presence of biological or riparian areas. A total of 7,465 acres (3,022 ha) of parcel disturbance were digitized in exurban Arivaca, acreage values were converted to a binary dependent variable and used in logistic regression analysis to test independent variables' predictive value. Four were statistically significant: parcel size, full cash value, mobile homes and site-built housing. Landscape fragmentation was also tested using the presence of the variable scoring highest in probability - site-built housing. Zones of influence with a negative ecological influence surrounded the homes - up to 5,055 acres (2,046 ha) were impacted. Interviews with an exemplary sample of residents regarding their land use ethic found all had very strong opinions on how their properties should be treated as well as undesirable land uses such as overgrazing, over-use of groundwater for short-term economic gain and use of off-road vehicles. An explanation of the small sample size of both planners and residents is warranted. Planners were limited to those working in Pima County government who had professional experience with the study area of Arivaca and were familiar with its particular situation. The number of Arivaca residents interviewed was intended to discern an exemplary group's opinions based on how large a parcel they owned, the various sizes being a typical cross-section of acreage in the study area. What these findings illustrate is (1) the difficulty of predicting human-induced disturbance, (2) land fragmentation is more than the actual areas of physical disturbance and (3) some residents are aware of impacts related to their activities, mitigating damage wherever possible.

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Magidi, James Takawira. "Spatio-temporal dynamics in land use and habit fragmentation in Sandveld, South Africa." Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_7886_1297841126.

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This research assessed landuse changes and trends in vegetation cover in the Sandveld, using remote sensing images. Landsat TM satellite images of 1990, 2004 and 2007 were classified using the maximum likelihood classifier into seven landuse classes, namely water, agriculture, fire patches, natural vegetation, wetlands, disturbed veld, and open sands. Change detection using remote sensing algorithms and landscape metrics was performed on these multi-temporal landuse maps using the Land Change Modeller and Patch Analyst respectively. Markov stochastic modelling techniques were used to predict future scenarios in landuse change based on the classified images and their transitional probabilities. MODIS NDVI multi-temporal datasets with a 16day temporal resolution were used to assess seasonal and annual trends in vegetation cover using time series analysis (PCA and time profiling).Results indicated that natural vegetation decreased from 46% to 31% of the total landscape between 1990 and 2007 and these biodiversity losses were attributed to an increasing agriculture footprint. Predicted future scenario based on transitional probabilities revealed a continual loss in natural habitat and increase in the agricultural footprint. Time series analysis results (principal components and temporal profiles) suggested that the landscape has a high degree of overall dynamic change with pronounced inter and intra-annual changes and there was an overall increase in greenness associated with increase in agricultural activity. The study concluded that without future conservation interventions natural habitats would continue to disappear, a condition that will impact heavily on biodiversity and significant waterdependent ecosystems such as wetlands. This has significant implications for the long-term provision of water from ground water reserves and for the overall sustainability of current agricultural practices.

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Riegler, Robert. "Fragmentation and integration : new evidence on the organisational structure of UK firms." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/12770/.

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This thesis will discuss how fragmented UK firms are and how they have changed between 1997-2008. We examine possible explanations for fragmentation and try to capture the effects of fragmentation on employment and labour productivity. We consider an organisational and a spatial dimension of fragmentation for the manufacturing and the tradable service sector. The data used comes from the Business Structure Database - a firm and plant level database which captures 99 percent of UK economic activity.

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Hensyl, Curtis Hamilton. "Impacts of Land and Ownership Characteristics on the Stumpage Prices for Virginia's Nonindustrial Forests." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/31706.

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The character of Virginia's nonindustrial private forests is changing primarily for two reasons. First, many large, continuous forested tracts are being sub-divided, into with the resulting smaller tracts purchased for amenity values and recreation instead of as a timber investment (Hodge 1993). Second, the demographics of non-industrial private forest (NIPF) landowners are shifting away from an agricultural, rural focus to an urban oriented lifestyle and absentee ownership. These changes may mean less timber available for purchase by the forest industry. Timber that is sold will be on smaller parcels that is bound to have an impact on the procurement activities of forest industries. However, little research has been performed on the impacts of site and landowner characteristic on stumpage prices. The objective of this research project is to identify how the stumpage price of timber is altered by the characteristics associated with the changing forest: decreasing tract size, decreasing harvested volumes, landowner residence, and landowner harvesting preferences. In addition to the price of timber, the competitiveness of timber sales is analyzed to determine what impact the fragmented forest could have on the competitiveness of timber markets. To perform the study, site and landowner information was collected for 138 recent NIPF timber sales that occurred within central Virginia. This region is identified as a critical area for the study of forestry activities because of the growing urban and suburban residential populations and the large amount of forest industry activities taking place there. Results show that access to the site is the most important characteristic determining the selling price of timber. Sites that are easy for logging crews and vehicles to approach dramatically increase the price paid per ton. Tract size is less important in determining bid prices for timber either once the total volume harvested passes a minimum of 500 tons, or there is mature hardwood sawtimber on the site and the acreage is greater than 50 acres. Landowners preference for select cut harvests results in a lower price per ton being paid by the purchaser due to the increased logging costs associated with this type of harvesting.
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Meyer, Christoph F. J. "Effects of rainforest fragmentation on neotropical bats - land-bridge islands as a model system." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-59301.

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Paudyal, Pramila. "Assessment of land cover change due to shale gas development in Harrison County, Ohio." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1564421778839792.

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Kibugi, Robert M. "Governing Land Use in Kenya: From Sectoral Fragmentation to Sustainable Integration of Law and Policy." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20268.

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The search for development that is sustainable often results in the complex challenge of having to reconcile the need for socio-economic activities with protection of the environment. This challenge of integrating such fundamentally important considerations that often contrast, but should be mutually supportive, is necessarily addressed by legal and policy frameworks of the country in question. These could be laws and policies with competence to manage the environment, or to manage socio-economic and political activities that impact the environment. This challenge is profound for developing countries like Kenya that experience higher levels of degradation, poverty and food insecurity. Arguably in this context, while addressing integration involves reconciliation of legal principles for a coherent legal concept of sustainability, it is also a serious matter of survival for millions of people. This raises compelling reasons to ensure that any legal reform measures positively impact how these people make decisions on the socio-economic utilization of land or forestry resources that they have access to. The research aimed to develop a legal and policy framework that will facilitate integration of environmental protection with socio-economic activities during land use decision making, as a mechanism to achieve sustainability. We investigated how a legal/policy framework, founded in the 2010 Constitution, and in environmental and tenure rights laws of Kenya, can conceptually reconcile the right (and duty) respecting a clean environment, with socio-economic rights. The research further analysed how such conceptual reconciliation can impact integration in policies, plans and decision making by sectoral laws and institutions to ensure environmental consideration across sectoral areas. To this end, we have proposed enacting a legal duty requiring tenure rightholders to integrate their socio-economic activities with environmental protection during land use decision making. We further frame mechanisms to guide the attitudes, and decisions of farmers and forest communities in making that transition to sustainable practices.

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Noble, Virginia Rose. "The effects of tropical forest fragmentation and land use on leaf litter decomposition and nutrient cycling." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44711.

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Forest conversion and fragmentation are major causes of diminished ecosystem function and biodiversity loss at a global scale. Understanding landscape effects on leaf litter decomposition and recycling of available nutrients is critical for conservation, especially in diverse tropical rainforests. Here, we studied the effects of land conversion and forest fragmentation on these two processes in a tropical ecosystem. We examined decomposition and nutrient cycling during the wet season in 22 sites across four habitat types: continuous forests, large fragmented forest patches, small fragmented forest patches, and orange plantations, in the tropical moist forest zone of NW Guanacaste, Costa Rica. The study employed a two-by-two factorial design to explore the effects of leaf litter type (site-specific litter vs. control litter) and mesh size (9 mm vs. 1 mm) on decomposition rate across land cover types. Litter bags with different mesh sizes either included (9 mm) or excluded (1 mm) macroinvertebrates. We removed litter bags from the field after 3 and 8 weeks, and cleaned and weighed the contents. Additionally, we utilized Plant Root Simulator (PRS™) Probes to examine nutrient cycling of 10 cations and anions including N, P, K, Ca, and Mg in all site-specific litter types and both mesh treatments. We found that the rate of decomposition differed depending on habitat type, leaf litter type and mesh size. Decomposition was faster in orange plantations compared to any other forest type, and decomposition was faster in forest fragments compared to continuous forests. We determined that these differences in decomposition rates were due predominantly to differences in site-specific litter quality. Only in forest fragments did the distance to forest edge impact macroinvertebrate feeding behaviour (seen in control litter), presumably due to spatial variation in leaf litter quality. Finally, mineralization of organic nutrients differed across the four habitat types. For example, nitrogen, which is an important compound for plant cell structure and function, mineralized more quickly in orange plantations than in forest habitats. This study highlights the importance of litter quality differences due to fragmentation and land use in altering leaf litter decomposition and nutrient cycling.

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Thapa, Vivek. "Habitat Fragmentation by Land-Use Change: One-Horned Rhinoceros in Nepal and Red-Cockaded Woodpecker in Texas." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33207/.

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This research focuses on the spatial analysis of the habitat of two vulnerable species, the one-horn rhinoceros in the grasslands of southern Nepal, and the red-cockaded woodpecker in the Piney woods of southeast Texas, in the USA. A study sites relevant for biodiversity conservation was selected in each country: Chitwan National Park in Nepal, and areas near the Big Thicket National Preserve in Texas. Land-use differs in the two study areas: the first is still undergoing agrarian development while the second is in a technological phase and undergoing urbanization processes. Satellite remote sensing images were used to derive land-cover maps by supervised classification. These maps were then processed by Geographic Information Systems methods to apply habitat models based on basic resources (food and cover) and obtain habitat suitability maps. Several landscape metrics were computed to quantify the habitat characteristics especially the composition and configuration of suitable habitat patches. Sensitivity analyses were performed as the nominal values of some of the model parameters were arbitrary. Development potential probability models were used to hypothesize changes in land-use of the second study site. Various scenarios were employed to examine the impact of development on the habitat of red-cockaded woodpecker. The method derived in this study would prove beneficial to guide management and conservation of wildlife habitats.

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Svensson, Ofir. "Does small-scale land use affect the understory birds negative in the Peruvian National Reserve Allpahuayo Mishana?" Thesis, Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-25017.

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Human activities that lead to fragmentation and habitat loss are big problems in the world. Due to global climate change the negative effects of fragmented habitats can be catastrophic for many organisms. In the Amazon rainforest, that is most sensitive to human impact, stands a big risk to lose its species diversity. Fragmentation and climate change together seems to escalate the death rate of rainforest plants and that will change the whole ecosystem. Birds and insects are depending on the trees and the trees faces big challenges now. Many of the rainforest organisms have been noticed to emigrate further up to northern altitudes due to the warmer climate and maybe also because of deforestation. Many of the lowland forest birds are predicted to distribute from their origin habitats. The national reserve Allpahuayo Mishana in the Peruvian Amazon is known for its diversity of birds. It is a big challenge for the reserve to maintain the origin forest composition from climate change, which will lead to losses of species. The reserve allows the local community to utilize the land for small-scale uses inside the protected zone. Many of the birds are sensitive for external disturbance. Most human activities are resulting in that the forest becomes less dense, which can lead to that the territory for the birds decreases. This makes it important for the reserve to improve the human land use not to restrict the birds' habitat inside the reserve. This project will investigate if the small-scale land uses affects the understory birds’ diversity and habitat negative. The purpose is to see if the fragmented forests in the reserve, closest to the utilized land, can functioning as a secondary forest for the understory birds, or are the understory birds limited by the small-scale land use, in the national reserve Allpahuayo Mishana? Four sites with various human activities were chosen to investigate if the sites contain any understory birds. The result showed that the most disturbed sites had poor bird diversity compare to the sites with no human disturbance.

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Telionis, Pyrros A. "Lyme Disease and Forest Fragmentation in the Peridomestic Environment." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/99281.

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Over the last 20 years, Lyme disease has grown to become the most common vector-borne disease affecting Americans. Spread in the eastern U.S. primarily by the bite of Ixodes scapularis, the black-legged tick, the disease affects an estimated 329,000 Americans per year. Originally confined to New England, it has since spread across much of the east coast and has become endemic in Virginia. Since 2010 the state has averaged 1200 cases per year, with 200 annually in the New River Health District (NRHD), the location of our study. Efforts to geographically model Lyme disease primarily focus on landscape and climatic variables. The disease depends highly on the survival of the tick vector, and white-footed mouse, the primary reservoir. Both depend on the existence of forest-herbaceous edge-habitats, as well as warm summer temperatures, mild winter lows, and summer wetness. While many studies have investigated the effect of forest fragmentation on Lyme, none have made use of high-resolution land cover data to do so at the peridomestic level. To fill this knowledge gap, we made use of the Virginia Geographic Information Network’s 1-meter land cover dataset and identified forest-herbaceous edge-habitats for the NRHD. We then calculated the density of these edge-habitats at 100, 200 and 300-meter radii, representing the peridomestic environment. We also calculated the density of <2-hectare forest patches at the same distance thresholds. To avoid confounding from climatic variation, we also calculated mean summer temperatures, total summer rainfall, and number of consecutive days below freezing of the prior winters. Adding to these data, elevation, terrain shape index, slope, and aspect, and including lags on each of our climatic variables, we created environmental niche models of Lyme in the NRHD. We did so using both Boosted Regression Trees (BRT) and Maximum Entropy (MaxEnt) modeling, the two most common niche modeling algorithms in the field today. We found that Lyme is strongly associated with higher density of developed-herbaceous edges within 100-meters from the home. Forest patch density was also significant at both 100-meter and 300-meter levels. This supports the notion that the fine scale peridomestic environment is significant to Lyme outcomes, and must be considered even if one were to account for fragmentation at a wider scale, as well as variations in climate and terrain.
M.S.
Lyme disease is the most common vector-borne disease in the United States today. Infecting about 330,000 Americans per year, the disease continues to spread geographically. Originally found only in New England, the disease is now common in Virginia. The New River Health District, where we did our study, sees over 200 cases per year. Lyme disease is mostly spread by the bite of the black-legged tick. As such we can predict where Lyme cases might be found if we understand the environmental needs of these ticks. The ticks themselves depend on warm summer temperatures, mild winter lows, and summer wetness. But they are also affected by forest fragmentation which drives up the population of white-footed mice, the tick’s primary host. The mice are particularly fond of the interface between forests and open fields. These edge habitats provide food and cover for the mice, and in turn support a large population of ticks. Many existing studies have demonstrated this link, but all have done so across broad scales such as counties or census tracts. To our knowledge, no such studies have investigated forest fragmentation near the home of known Lyme cases. To fill this gap in our knowledge, we made use of high-resolution forest cover data to identify forest-field edge habitats and small isolated forest patches. We then calculated the total density of both within 100, 200 and 300 meters of the homes of known Lyme cases, and compared these to values from non-cases using statistical modeling. We also included winter and summer temperatures, rainfall, elevation, slope, aspect, and terrain shape. We found that a large amount of forest-field edges within 100 meters of a home increases the risk of Lyme disease to residents of that home. The same can be said for isolated forest patches. Even after accounting for all other variables, this effect was still significant. This information can be used by health departments to predict which neighborhoods may be most at risk for Lyme. They can then increase surveillance in those areas, warn local doctors, or send out educational materials.

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Bandiera, Oriana. "Economic Institutions in Developing Countries." Thesis, Boston College, 1999. http://hdl.handle.net/2345/1752.

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This thesis is a collection of three essays, each of which analyses an economic institution in one or more developing countries. A careful analysis of institutions is crucial for the understanding of economic performance and for the design of effective policy measures. In the first essay, "On the Structure of Tenancy Contracts" I analyse the effect of crop and tenant characteristics on the form and on the length of tenancy contracts. Using a principal-agent model I show that highpowered incentives are used when, due to the characteristics of the crop, their benefit is high and/or when, due to the characteristics of the tenant, their cost is low. The theoretical predictions are consistent with the empirical evidence from a unique data set of 705 contracts. The purpose of the second essay, "Competing for Protection: Land Fragmentation and the Rise of Mafia in 19th Century Sicily", is to identify the conditions that fostered the development of the mafia. I argue that in the context of 19th century Sicily, land fragmentation was crucial for the rise of mafia. Using a menu-auction model I show that, by inducing landlords' competition for protection, land fragmentation increases the profits of mafia groups even if the assets in need of protection are unchanged. I show that the predictions of the theory are consistent with the available empirical evidence from a sample of 70 Sicilian villages. In the third essay, "Does Financial Reform Raise or Reduce Savings?", we analyse the effect of financial liberalisation on private savings in eight developing countries. To this purpose we construct an index which summarises the reform process and estimate an error correction model for savings. We find that the effect of financial reform on savings is ambiguous
Thesis (PhD) — Boston College, 1999
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Economics

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Deakin, Elizabeth Louise. "Impacts of land-use intensification on forest remnants embedded within production landscapes." Thesis, University of Canterbury. Biological Sciences, 2013. http://hdl.handle.net/10092/8712.

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Agricultural expansion has transformed and fragmented natural forest habitats at an alarming rate, and dramatic increases in agricultural intensification have since taken place in order to keep pace with human population growth and food demands. This simultaneously poses a considerable threat to biodiversity in agricultural landscapes, as production land is now one of the largest terrestrial biomes on the planet. Therefore, its contribution to biodiversity conservation is critical. Links between the intensification of agricultural systems and ‘in situ’ declines of biodiversity on farmland have been well documented. However, despite growing recognition that system inputs such as fertiliser and livestock can move or ‘spillover’ into adjacent natural habitats, there has been no direct quantification of the extent of impacts in recipient ecosystems. These abiotic and biotic pathways can cause dramatic impacts on the diversity, composition, and functioning of remaining natural ecosystems, and on their ability to provide a variety of essential ecosystem services. Due to concerns regarding future food security, balancing trade-offs between agriculture and conservation has subsequently become a hot topic in ecological research. However, without any direct quantification of the off-site ecological impacts of agricultural intensification in mosaic landscapes, it is inherently difficult to fully evaluate strategies aimed at balancing production and conservation. Using New Zealand farming systems as a case study, this thesis aims to address gaps in our current understanding of how increasing agricultural intensification impacts biodiversity in native forest remnants embedded within production landscapes. The first main chapter explores whether the magnitude of ecological impact in forest remnants (for a suite of 26 response measures) and severity of edge effects, scale with the degree of land-use intensity in surrounding agricultural pastures. This chapter also examines whether ecological responses differ in remnants ‘spared’ for conservation purposes (i.e. where livestock are excluded by fencing). The second chapter uses a model food-chain approach native to New Zealand, to test whether nutrient spillover from agricultural pastures influences plant-herbivore and herbivore-parasitoid interactions in forest remnants. This chapter also includes a large-scale common garden fertilisation experiment using the same tri-trophic system, which was established to examine bottom-up multi-trophic responses to the independent and combined effects of Nitrogen (N), Phosphorus (P) and cow dung and urine. The third main chapter uses a novel stable isotope approach for quantifying community-wide incorporation of resources into trophic structure. I test for the first time whether increasing intensity of farming systems drives greater nutrient spillover spatially into adjacent forest remnant soils and examine scaling effects of 15N (as a marker for anthropogenic N) through multiple trophic levels. Beyond finding that agricultural land-use intensity generally has negative off-site effects on biodiversity, the key findings of this thesis were (i) spillover of nitrogen and phosphorus from agricultural systems into adjacent remnant soils is exacerbated by increases in land-use intensity, with (ii) percolating bottom-up effects on plant and insect community dynamics. (iii) The magnitude of ecological impacts in forest remnants scales linearly with increasing land-use intensity, as does (iv) direct anthropogenic N enrichment across multiple trophic levels, which has the potential to severely jeopardise the stability of ecologically important remnant habitats. (v) Although there were stark structural differences in remnants with and without livestock exclusion, impacts of land-use intensity on ecological response metrics were actually comparable across all sites. (vi) Livestock exclusion should be a priority first step towards conserving native forest remnants, however it should be recognised that fencing does not prevent abiotic channels of nutrient spillover (fertiliser drift, overland flow, leaching) in land characteristic of land spared for nature. (vii) Consequently, increasing land-use intensity compromises the effectiveness of the land-sparing trajectory for conserving native biodiversity, which is currently undertaken in New Zealand production systems. Given the overall strength of these findings and the novel, ecosystem-wide and landscape-scale approaches taken to address fundamental questions, the work in this thesis greatly enhances our knowledge of the relationships between agricultural productivity and ecological impacts in spatially-coupled ecosystems. This is highly important, not only in New Zealand but worldwide, as it is anticipated that unstoppable human population growth and food security pressures will cause ecological impacts both on the farm and in adjacent natural ecosystems to become even more severe. Therefore, determining the relationship between land-use intensification and biodiversity loss represents the cornerstone of sustainable agricultural development in the future.

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Hurston, Heather. "Historical Land Fragmentation and its Effects on Genetic Diversity and Parasitism of Island Populations of Podarcis erhardii (Lacertidae, Reptilia)." ScholarWorks@UNO, 2007. http://scholarworks.uno.edu/td/1072.

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The Pleistocene land bridge islands in the Aegean Sea make an ideal natural experimental system for testing how island age, area and isolation affect genetic variation. My research focuses on the population genetics of the Aegean wall lizard Podarcis erhardii (Lacertidae, Reptilia), which because of its wide distribution, and poor dispersal abilities is a sensitive indicator of fragmentation history. I predict that genetic diversity will be positively correlated with island area and negatively correlated with age. I also predict that island characteristics, host genetic variability or grazing may impact parasite prevalence. Findings showed that larger islands maintained more genetic diversity than smaller islands and older islands have higher mite loads. Geographic distance was unrelated to genetic divergence. Tick prevalence was significantly associated with past grazing practices. This study provides a unique opportunity to disentangle factors that may influence the retention of genetic diversity and prevalence of ectoparasites in natural populations.

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Wang, Chuyuan. "Forest fragmentation in the Brazilian Amazon: evidence from land reform settlements along the Transamazon Highway and in Southern Pará." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/13617.

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Master of Arts
Department of Geography
Marcellus M. Caldas
The democratization of Brazil in 1985 brought hope and impetus for agrarian reform, especially after the proposal of a series of new settlement projects by many Presidents to expropriate and redistribute lands to the Brazil’s landless. The landless poor, however, took this new state-sanctioned program into their own hands and started occupying lands to build land reform settlements. Social Movement Organizations (SMOs) that were established and working illegally gradually emerged and invaded large private landholdings near urban areas with a specific political agenda, while far rural landless people targeted unclaimed open public forest for land occupation to build spontaneous land reform settlements. Both types of land occupation actions constituted the Direct Action Land Reform (DALR). Recent literature has outlined the socio-economic circumstance that affected DALR, DALR settlement formation process and its implication to deforestation; however, no research considers forest fragmentation in these land reform settlements and its relationship with demographic factors. In order to fill this gap in the literature, this thesis first compared the temporal and spatial dynamics of deforestation fragment patterns in spontaneous DALR settlements around the municipality of Uruará along the Transamazon Highway, and in SMO-led DALR settlements in Southern Pará region using satellite imagery from 1986 to 2010 and three landscape metrics (patch mean area, area-weighted mean shape index and patch cohesion index). Metrics results were then respectively analyzed with selected field survey data to discover the impacts of demographic factors on forest fragmentation in DALR settlements. Results showed that SMO-led DALR settlements in Southern Pará primarily exhibited larger, more irregularly shaped and more physically connected deforestation fragments than spontaneous DALR settlements in the Uruará region over the whole study period. Demographic factors that influenced forest fragmentation in DALR settlements included the number of people and children per household, family lot size, percentage of families receiving credit and the distance between the family lot and the nearest city. At last, constructive policy recommendations were provided based on research findings.

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Gatela, Sierrane Grace S. "Building Bridges for Wildlife: Modeling the Richness of Human-Wildlife Encounters Over 15 Years of Urban Growth in the Sky Islands." The University of Arizona, 2016. http://hdl.handle.net/10150/608603.

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Sustainable Built Environments Senior Capstone Project
This study analyzes 15 years of wildlife tracking data across more than 40 transects in the Sky Islands surrounding landscape to investigate how human-wildlife encounters may respond to a decade of land development. The average detection of species per visit (ADPV), the quantification for human-wildlife encounters and indicator of species richness, was calculated for each transect across two sample periods 2001-2011 and 2011-2015. ArcMap was used to visualize the ADPV across sampling sites in the Sky Islands region. The p-value was then calculated to determine whether there was a significant difference between the ADPV of all species and of focal species before and after 2011. The results concluded there was no significant difference and the null hypothesis was accepted.

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Montoya, Olga Lucia. "Espace, temps et présence dans les dramaturgies du no man's land urbain. Vers un drame performatif?" Thesis, Paris 3, 2013. http://www.theses.fr/2013PA030084.

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A travers l’analyse de huit pièces de théâtre se déroulant dans des no man’s lands urbains et que nous réunissons sous ce que Jean-Pierre Sarrazac appelle « la dramaturgie du no man’s land », nous tentons de montrer comment le drame moderne et contemporain continue à se réinventer par l’adoption d’autres modèles dramaturgiques. Notre recherche s’applique surtout à l’un de ses modèles, celui de la performance. Comme le dit Jacques Derrida à propos de la déconstruction, pour les auteurs de ces pièces, il s’agit aussi par la représentation du no man’s land urbain de «penser à partir de ce passage, à la limite, à un ailleurs-ici »1. Ce non-lieu hétérotopique leur permet à la fois de penser la violence du monde tout en continuant à expérimenter de nouvelles formes du drame.En se situant sur cette ligne, sur cette frontière, « dans un ailleurs de certitudes »2, ces auteurs donnent cours à un drame qui, succédant à la catastrophe de la deuxième guerre mondiale, à la chute des utopies de gauche et à l’accroissement affolé du capital, ne cherche pas à donner de réponses à la manière du théâtre brechtien, mais à soulever des questions. Par cette déconstruction et par l’adoption des éléments performatifs dans le traitement du temps, de l’espace et de la présence de l’auteur et du personnage, ces auteurs, Harold Pinter, Botho Strauss, Bernard-Marie Koltès, Edward Bond, Rodrigo Garcia, Tim Etchells, Victor Viviescas et Carolina Vivas, mettent le spectateur en relation directe avec la scène de cette cruauté annoncée par Artaud qui ne se limite pas à une imitation mais est aussi une expérience au présent : celle du vide
By analyzing eight plays taking place in urban no-man’s-lands, which we have grouped under the heading of what Jean-Pierre Sarrazac calls “no-man’s-land dramaturgy,” we attempt to show how modern and contemporary drama continues to reinvent itself through the adoption of other dramaturgic models. Our research is applied especially to one of these models – performance art. As Jacques Derrida says in regards to deconstruction, the authors of these plays, too, «think about this passage onward, about a limit, about an elsewhere-here-and-now»3 by the representation of an urban no-man’s-land. This heterotopian non-place allows them to reflect on the violence of the world even as they experiment with new forms of drama.By going out on that edge, that border, out to «an elsewhere of certitudes»4 these authors set in motion a drama which, coming as it does after the catastrophe of the second world war, after the fall of leftist utopias, on the heels of madly spiraling capital, seeks to pose questions rather than provide answers in a Brechtian sense. Through this deconstruction and by the now adoption of performative elements in the treatment of time, space and presence of the author and of the character, authors Harold Pinter, Botho Strauss, Bernard-Marie Koltès, Edward Bond, Rodrigo Garcia, Tim Etchells, Victor Viviescas and Carolina Vivas put the audience directly in touch with the cruelty foretold by Artaud, which isn’t limited to imitation but is also an experience of the present – that of the void

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Melito, Melina Oliveira. "Effects of forest fragmentation on biomass in tropical forests." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-28032017-144953/.

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In spite tropical forests are the most important terrestrial global carbon sinks due to carbon storage in aboveground biomass, it is also the primary target of deforestation. The conversion of Tropical forests into anthropogenic areas might disrupt biological flux and also lead to severe microclimatic changes at forest edges. These combined effects can trigger profound changes in plant composition through both high mortality of fragmentation-sensitive species and proliferation of disturbed-adapted species which will ultimately impacts carbon storage. Thus, our main objective in this study was understand the role of human-induced disturbances in modulate the dimension of biomass loss at tropical forests. We applied a systematic literature review searching for empirical evidences that edge effects can drive biomass loss in tropical forests (Chapter 2). Our findings highlighted the gap of knowledge about the pattern and process related to biomass loss in tropical forests. To strengthen this understanding, we formulated a conceptual model linking landscape structure and patch-level attributes to severity of edge effects affecting aboveground biomass. Our model hypothesizes that habitat amount, isolation, time since edge creation, and the synergism between edge distance, patch size, and matrix type are the main drivers of biomass loss in anthropogenic tropical forests. We thus used a large plant dataset (18 503 trees ≥ 10 cm dbh) from 146 sites distributed across four Mexican and four Brazilian rainforest regions to test our conceptual model predictions, specifically the influence of forest cover, site isolation, edge distance, patch size and type of matrix on biomass (Chapter 3). We observed that carbon-rich sites presented species that are typical of old-growth forests (shade-tolerant, large-seeded, zoocoric) contrasting to carbon-poor sites composed by disturbed-adapted species (pioneer occupying the understory). Large shade-tolerant trees (≥ 40 cm dbh) were impacted severely by the combination of forest loss and edge effects. Edge distance, patch size, and the amount of open-matrix strongly influence small shade-tolerant trees (≤ 20 cm dbh). Although our results do not fully corroborate the initial predictions of the conceptual model, they support the idea that landscape composition interact with patch structure and ultimately impacts biomass stocks in fragmented tropical forests. Finally, we further investigated if the disturbance level of the region influences plant-structure responses to forest loss (Chapter 4). Biomass, but not plant density, was affected by forest loss in regions with intermediate disturbance levels, i.e. regions showing a combination of moderate deforestation (20-40% of remaining forest cover) disturbed during the past 30-60 years, high defaunation but harboring relictual populations of large-mammals, and areas mostly composed by heterogeneous matrices. In general, our findings highlight that both landscape composition and patch structure are the main drivers of biomass loss in Neotropical forests, and that the landscape context must be considered to obtain more reliable estimations of carbon emissions due to forest degradation. Landscape planning (e.g. restoration of forest cover) should be included in conservation strategies in order to sustain carbon storage. Moreover, we advocate that conservation initiatives will be less costly and more effective if implemented in areas under intermediate disturbance levels
Apesar das florestas tropicais serem a mais importante fonte mundial de carbono da porção terrestre do globo devido ao armazenamento de carbono na biomassa acima do solo, elas são também o alvo primário do desmatamento. A conversão das florestas Tropicais em áreas antropogênicas pode interromper o fluxo biológico e também levar a severas mudanças microclimáticas na borda dos fragmentos. A combinação desses efeitos pode engatilhar profundas mudanças na composição da vegetação através tanto da mortalidade de espécies sensíveis à fragmentação como também pela proliferação de espécies adaptadas distúrbios, com impactos finais nos estoques de carbono. Assim, o maior objetivo desse estudo foi compreender o papel dos distúrbios induzidos pelo homem na modulação da dimensão da perda de biomassa em florestas Tropicais. Nós aplicamos uma revisão sistemática da literatura procurando por evidências empíricas de que o efeito de borda pode levar a perda de biomassa em florestas tropicais (Capítulo 2). Nossos resultados destacam a lacuna de conhecimento entre padrões e processos relacionados à perda de biomassa em florestas Tropicais. Para fortalecer esse conhecimento, nós formulamos um modelo conceitual conectando estrutura da paisagem e atributos na escala do fragmento à severidade do efeito de borda, e assim afetando a biomassa acima do solo. Nosso modelo hipotetiza que a quantidade de hábitat, o isolamento, o tempo desde a formação da borda e o sinergismo entre tamanho do fragmento, distância da borda e tipo de matriz são os principais condutores de perda de biomassa em florestas Tropicais antropogênicas. Utilizando um grande banco de dados (18 503 árvores ≥ 10 cm dap) provenientes de 146 locais distribuídos em quatro regiões de floresta úmida no México e quatro no Brasil, nós então testamos as predições do nosso modelo conceitual. Especificamente, a influência da cobertura florestal, isolamento, distância da borda, tamanho do fragmento e tipo de matriz sobre a biomassa (Capítulo 3). Nós observamos que áreas com muito carbono apresentaram espécies típicas de florestas maduras (tolerantes ao sombreamento, zoocóricas, com sementes grandes) contrastando com áreas com pouco carbono compostas por espécies adaptadas à distúrbio (pioneiras ocupando o sub-bosque). Árvores grandes tolerantes ao sombreamento (≥ 40 cm dap) foram impactadas severamente pela combinação de perda de cobertura florestal e efeitos de borda. Distância da borda, tamanho do fragmento e a extensão da área de matriz aberta influenciaram fortemente as árvores pequenas tolerantes a sombreamento (≤ 20 cm dap). Apesar dos nossos resultados não corroborarem completamente as predições iniciais do nosso modelo conceitual, eles dão suporte à ideia de que a composição da paisagem interage com a estrutura do fragmento com impactos finais nos estoques de biomassa em florestas Neotropicais. Por fim, nós investigamos se o nível de distúrbio da região pode influenciar nas respostas da estrutura da vegetação à perda de cobertura florestal. Biomassa, mas não a densidade de indivíduos, foi afetada pela perda de cobertura florestal em regiões com nível intermediário de distúrbio, i.e. regiões apresentando uma combinação de níveis moderados de desmatamento (20-40% de cobertura florestal remanescente) em que a perturbação ocorreu ao longo dos últimos 30-60 anos, com alto grau de defaunação mas ainda abrigando populações relictuais de grandes mamíferos e, em sua maioria, compostos por uma matriz heterogênea. Em geral, nossos resultados destacaram que tanto a composição da paisagem como a estrutura do fragmento são os principais condutores de perda de biomassa em florestas Neotropicais e que o contexto da paisagem deve ser considerado para se obter estimativas mais confiáveis de emissão de carbono devido à degradação florestal. O planejamento da paisagem (e.g. restauração da cobertura florestal) deve ser incluído em estratégias de conservação em ordem de sustentar o armazenamento de carbono. Além disso, nós defendemos que iniciativas de conservação serão menos custosas e mais efetivas se implementadas em áreas sob níveis intermediários de distúrbio

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29

Le, Moine Rebecka. "The land use cover changes from 1992 to 2011 in Karbi Anglong, Assam, India." Thesis, Linköpings universitet, Ekologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-79347.

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With an increased human impact, natural resources are under great pressure. Deforestation is one effect of this, and the largest threat against biodiversity.. Changes in tropical habitats is a major concern for conservation biologists, due to its high biodiversity and rapid decreased area. Recently, developmental activities and habitat destruction have caused a major decline in the abundance of the terrestrial mega-fauna.This is especially evident in areas with a high human population and a rich mega-fauna as in India. The purpose of this project was to determine the land-use cover change (LUCC) in the area of Karbi Anglong, which lies in the middle of Assam, India. This was done by identifying different vegetation types from satellite images, from the years 1992, 2002 and 2011 using a remote sensing application (ERDAS) and ArcGIS. Interviews in the area werealso operated, and data about how animal use the corridors were used along with registered human-tiger conflicts. The results show that during the first period, a total of 360 km2 of the area changed vegetation type, mostly due to an increase of agricultural areas. The second largest change (79 km2) was an increase of moist mixed deciduous forest which seems to have taken over some of the semi evergreen forest’s previous area. If that is the case it is most likely an effect of selective logging from the local people, who use fire wood as fuel.All in all, there has been a great habitat loss along withfragmentation of the landscape. The conflict data shows that tigers are present between the core areas, and the interviews show that the migrations of other animals are also common.To maintain the high ecological values in Karbi Anglong, it is of great importance to maintain connectivity between core areas and stop further habitat loss and fragmentation.

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30

Gimona, Alessandro. "Land use, soil and climatic factors associated with the demographic fragmentation of the rook (Corvus frugilegus L.) population in Scotland." Thesis, University of Aberdeen, 1998. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU106045.

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This study investigates the influence of autoecological factors both on the spatial pattern of abundance, and on the demographic fragmentation, of the breeding population of the Rook (Corvus frugilegus L.) in Scotland. Two scales of analysis are considered, namely the regional scale (Scotland) and the landscape scale (Ythan catchment area). The study focuses on the investigation of how land use factors interact with other environmental variables. Patterns of association of the breeding density with land cover, climatic and soil factors are searched for and statistically examined. Soil factors, in particular, have been investigated in detail for the first time, because of their potential to influence the population of earthworms, the main prey for the Rook during the breeding season. A geostatistical simulation is used to address the problem of data spatial autocorrelation. Several models are integrated in a GIS environment to develop an index of potential energy intake (IPI), aimed at reflecting the long term seasonal availability of invertebrate prey (mainly earthworms) on grasslands. The results are scale dependent. At the regional scale, they indicate that the most important variables influencing the demographic fragmentation are the availability of grasslands and soil moisture. It is shown that this translates into potential availability of spring and summer food resources, in the form of soil invertebrates. The results indicates that, at least in Scotland, the decline in quality of grasslands as a habitat for soil invertebrates, rather than that in winter cereal stubble, might have been associated with the past Rook population decline. At the landscape scale, no difference was found between IPI values around colonies, versus IPI values around wooded areas devoid of colonies, or between IPI and number of nests. It is hypothesised that conspecific attraction contributes to decoupling between resources and breeding density at the landscape scale. The results of this study support the hypothesis of Brown et al. (1995) that the distribution of a species might be understood in terms of the extent to which local environmental conditions meet the niche requirements, but highlight the importance to account for the scale at which such requirements are assessed.

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Stevenson, Megan N. "The Effects of Land Cover Change on the Spatial Distribution of Lyme disease in Northern Virginia Since 2005." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/94560.

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Lyme disease has been a growing problem in the United States over the last few decades, and is currently the most common vector-borne disease in the country. This research evaluates the land cover within specified counties of northern Virginia to determine if a correlation exists between forest fragmentation, suburbanization, and cases of human Lyme disease as has been demonstrated in other Lyme endemic regions in the United States. Few studies have focused specifically on northern Virginia when considering the impacts of land cover change on Lyme disease. Discovered through the use of geospatial and statistical analysis, the cluster of Lyme disease cases in northern Virginia are associated with forest fragmentation within the study region, which creates an ideal habitat for black-legged ticks and the white-footed mouse, allowing for an increase in Lyme disease transfer from vector to humans. The goal is for the research findings to be applicable to other regions with similar land cover types. Regions with similar characteristics would then be able to recognize the potential risk of human Lyme disease and implement ways to reduce the Lyme disease risk associated with suburban development. The purpose of this study is to answer the following research questions: 1) How has the spatial distribution of Lyme disease in Northern Virginia changed since 2005 with respect to land cover? 2) Which suburban communities are more at risk for Lyme disease when considering their land cover types and the increasing spatial distribution of Lyme disease?
Master of Science
Lyme disease has been a growing problem in the United States over the last few decades, and is currently the most common vector-borne disease in the country. This research evaluates the land cover within specified counties of northern Virginia to determine if a correlation exists between forest fragmentation, suburbanization, and cases of human Lyme disease as has been demonstrated in other Lyme endemic regions in the United States. Few studies have focused specifically on northern Virginia when considering the impacts of land cover change on Lyme disease. Discovered through the use of geospatial and statistical analysis, the cluster of Lyme disease cases in northern Virginia are associated with forest fragmentation within the study region, which creates an ideal habitat for black-legged ticks and the white-footed mouse, allowing for an increase in Lyme disease transfer from vector to humans. The goal is for the research findings to be applicable to other regions with similar land cover types. Regions with similar characteristics would then be able to recognize the potential risk of human Lyme disease and implement ways to reduce the Lyme disease risk associated with suburban development. The purpose of this study is to answer the following research questions: 1) How has the spatial distribution of Lyme disease in Northern Virginia changed since 2005 with respect to land cover? 2) Which suburban communities are more at risk for Lyme disease when considering their land cover types and the increasing spatial distribution of Lyme disease?

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Poor, Erin Elizabeth. "A multiscale analysis and quantification of human impacts on Sumatran tiger (Panthera tigris sumatrae) habitat in Riau, Sumatra." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/85130.

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Worldwide, we are losing biodiversity at unprecedented rates, and due to deforestation, degradation and poaching, Southeast Asian wildlife is facing extreme threats. Indonesia recently eclipsed Brazil in having the world's highest deforestation rate, largely due to the rise of the palm oil industry. Indonesia contains multiple biodiversity hotspots and endangered species such as the Sumatran tiger (Panthera tigris sumatrae). While Riau Province, Sumatra, produces approximately 20% of the world's palm oil, tigers still inhabit parts of Riau, though their habitat and prey are understudied. Thus, in this research, I aim to assess and quantify how tiger habitat has changed, how it will continue to change, and provide recommendations on how to improve the landscape for tigers. I create the first accuracy-assessed land cover maps of Riau, and then predict land cover change from 2016 – 2050. Using this newly created land cover map, I assess whether Tesso Nilo National Park, Bukit Tigapuluh National Park, and Rimbang Baling Wildlife Reserve are effective at preventing deforestation. Next, I examine human impacts within Tesso Nilo specifically, due to its suitability for oil palm and its potential as a stepping stone for wildlife movement from the western, mountains to the eastern peatlands of Sumatra. Finally, I examine impacts of human presence within Rimbang Baling on felid-prey relationships. I predict that by 2050, over 60% of natural forest in Riau will be lost, and all protected areas only confer low levels of protection. I determined that Tesso Nilo National Park has nearly 2500 km of roads within it and no areas within the park are untouched by humans. Wildlife detections were low near the boundary of Rimbang Baling and there was evidence of humans negatively impacting mousedeer (Tragulus spp) behavior. I suggest focusing on securing the habitat within Rimbang Baling and Bukit Tigapuluh to ensure habitat for dispersing tigers from the western mountains, in addition to, and perhaps before focusing on restoring Tesso Nilo and creating wildlife corridors. While tiger recovery in Riau will be difficult, with education, dedication, persistence and intelligent planning, tigers may be able to persist in this unique ecosystem in the long-term.
Ph. D.

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Kitamura, Shuhei. "Land, Power and Technology : Essays on Political Economy and Historical Development." Doctoral thesis, Stockholms universitet, Nationalekonomiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-131258.

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Land Ownership and Development: Evidence from Postwar Japan This paper analyzes the effect of land ownership on technology adoption and structural transformation. A large-scale land reform in postwar Japan enforced a large number of tenant farmers who were cultivating land to become owners of this land. I find that the municipalities which had many owner farmers after the land reform tended to experience a quick entry of new agricultural machines which became available after the reform. The adoption of the machines reduced the dependence on family labor, and led to a reallocation of labor from agriculture to industries and service sectors in urban centers when these sectors were growing. I also analyze the aggregate impact of labor reallocation on economic growth by using a simple growth model and micro data. I find that it increased GDP by about 12 percent of the GDP in 1974 during 1955-74. I also find a large and positive effect on agricultural productivity. Loyalty and Treason: Theory and Evidence from Japan's Land Reform A historically large-scale land reform in Japan after World War II enforced by the occupation forces redistributed a large area of farmlands to tenant farmers. The reform demolished hierarchical structures by weakening landlords' power in villages and towns. This paper investigates how the change in the social and economic structure of small communities affects electoral outcomes in the presence of clientelism. I find that there was a considerable decrease in the vote share of conservative parties in highly affected areas after the reform. I find the supporting evidence that the effect was driven by the fact that the tenant farmers who had obtained land exited from the long-term tenancy contract and became independent landowners. The effect was relatively persistent. Finally, I also find the surprising result that there was a decrease, rather than an increase, in turnout in these areas after the reform. Geography and State Fragmentation We examine how geography affects the location of borders between sovereign states in Europe and surrounding areas from 1500 until today at the grid-cell level. This is motivated by an observation that the richest places in this region also have the highest historical border presence, suggesting a hitherto unexplored link between geography and modern development, working through state fragmentation. The raw correlations show that borders tend to be located on mountains, by rivers, closer to coasts, and in areas suitable for rainfed, but not irrigated, agriculture. Many of these patterns also hold with rigorous spatial controls. For example, cells with more rivers and more rugged terrain than their neighboring cells have higher border densities. However, the fragmenting effects of suitability for rainfed agriculture are reversed with such neighbor controls. Moreover, we find that borders are less likely to survive over time when they separate large states from small, but this size-difference effect is mitigated by, e.g., rugged terrain.

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Piquer-Rodríguez, Maria. "Effects of policies and zoning on future land use in Argentina." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2017. http://dx.doi.org/10.18452/17762.

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Landwirtschaftliche Expansion und Intensivierung treiben die Umwandlung natürlicher Ökosysteme weltweit. Bis heute ist unklar, inwieweit politische Maßnahmen negative Folgen für die Umwelt minimieren können. Die Kombination mit Szenarien-Analysen kann ein Rahmen zur Unterstützung von Planungsprozessen schaffen, um potentielle Auswirkungen von politischen Maßnahmen zu erforschen. Das Ziel dieser Dissertation war es, die Triebkräfte der Veränderung von Argentiniens Agrarlandschaften zu verstehen, potentielle zukünftige Landnutzungsveränderungen zu analysieren und den Einfluss ökonomischer und naturschutzbezogener politischer Maßnahmen auf diese zu erfassen. Im ersten Teil der Dissertation wurden die Triebkräfte landwirtschaftlichen Landnutzungswandels mittels eines Nettoertrags-Modells ermittelt. Danach wurde der Einfluss von ökonomischen und naturschutzbezogenen Maßnahmen auf zukünftige Landnutzungsveränderungen sowie auf die Konnektivität von Waldgebieten mit Hilfe von Landnutzungs-Szenarien analysiert. Die Ergebnisse zeigen, dass landwirtschaftliche Intensivierung von ökonomischen Maßnahmen getrieben ist, während landwirtschaftliche Expansion durch naturräumliche Eigenschaften und Zonierungsprogramme jenseits der Profitmaximierung determiniert wird. Politische Maßnahmen mögen einen geringeren Einfluss auf Landnutzungswandel haben als bisher erwartet. Die Entwicklung von Agrarland konzentriert sich auf Gebiete mit hoher Priorität für den Umweltschutz. Zonierungsprogramme wie das Argentinische Waldgesetz stellen wirkungsvolle Maßnahmen dar, um umweltschädigenden Entwicklungen vorzubeugen. Die Erkenntnisse zeigen, dass Naturschutz nicht zwingend im Konflikt mit ökonomischer Entwicklung steht, denn mittels Landschaftsplanung kann die Konnektivität von Waldgebieten auch unter gleichbleibenden Abholzungsraten bewahrt werden. Die Dissertation zeigt den Mehrwert von a-priori Evaluierungen der potentiellen Einflüsse von Maßnahmen auf Landnutzungswandel.
Agricultural expansion and intensification drive the conversion of natural areas worldwide. Yet, it is not clear where and how much production would need to expand and intensify to meet future demands and how policies may help minimizing environmental trade-offs. Particularly the latter requires an understanding of the underlying forces that drive agricultural land-use changes. This offers a framework for planners and decision makers to explore potential impacts from policies, especially in very dynamic regions. Argentina, where agricultural expansion and intensification result in dramatic conversions of natural areas, is a good example of a dynamic human-environment system. The goal of this thesis was to understand the drivers of agricultural land-use change and to explore future trajectories of land-use change, and how economic and conservation policies may impact them. This thesis examines drivers of agricultural land-use changes using a net returns model of agricultural production. Then, it evaluates the effects of economic and conservation policies on future land-use changes and on the connectivity of forests by developing scenarios of future land-use change. Results highlight that agricultural intensification in Argentina is driven by economic interventions, whereas agricultural expansion primarily responds to environmental characteristics and zonation programs. Economic policies may have less power in governing land use changes than previously thought, as results suggest that there are other factors, than profit maximization, influencing land conversions. Future agricultural development would occur in priority areas for conservation in Argentina, but zonation policies, such as the Forest Law, appear to be powerful in limiting potential environmental trade-offs. Conservation planning does not necessarily need to conflict with economic development, since under similar deforestation rates; landscape planning can preserve forest connectivity in the Chaco.

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Bregman, Tom P. "The impacts of human land-use change on avian diversity and associated ecosystem functions." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:b0364847-0949-4d9f-bf2a-2cca62a988a7.

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Understanding the impacts of land-use change on biodiversity and the ecosystem services that it provides is of great importance given unprecedented growth of the human population. Past studies attempting to explore these impacts have described the overall structure of communities (i.e. species richness and trait diversity) across gradients of local scale degradation and fragmentation, and have sought to identify whether the loss of species following land-use change is non-random. Yet, despite a wealth of research we still lack a generalised understanding of how land-use change impacts on traits responsible for determining species sensitivity and their role within ecosystems, particularly for vertebrates. Moreover, despite the importance of niche-based processes in the assembly of communities, we have not yet elucidated whether these are important in mediating the collapse of communities in human-dominated landscapes. To fill these existing research gaps, I collated comprehensive avian species inventories from fragmented and degraded forests and compared their structure with communities existing in continuous forests. In Chapter 2, I tested whether sensitivity of species to forest fragmentation varies between the temperate zone and the tropics and whether there are key differences in the size of fragments required to maintain ecosystem processes in these regions. I found that sensitivity to fragmentation varies according to functional group and body mass, with the prevalence of insectivores and large frugivores declining in relation to fragment size, particularly in tropical fragments smaller than 100 ha. In Chapter 3, I tested whether functional diversity and the mean position of trait diversity of insectivores and frugivores, changed across a gradient of intensifying land-use change. I found a decline in the functional diversity of forest species and a shift in the mean community traits for both forest and non-forest species. In Chapter 4, I tested whether the structure of tropical bird communities are influenced by species interactions in a fragmented landscape. I found increasing over-dispersion in functional and phylogenetic trait relatedness among species with decreasing fragment size, suggesting that competitive interactions are important in the disassembly of avian communities. In Chapter 5, I modelled the impact of forest cover change on ecosystem function across the Brazilian Amazon, focusing on seed dispersal by birds. Furthermore, I tested whether ecosystem function declined linearly with decreased forest cover after accounting for differences in the underlying pools of species. I found the lowest levels of functional diversity along the southern arc of deforestation and that the dispersal of large seeds showed some resilience to declining forest cover. Taken together, my results suggest that the loss of species from communities in degraded and fragmented landscapes is strongly non-random. Insectivores and large frugivores are most sensitive to land-use change, with species located in the densest parts of trait space being most threatened by a decline in forest patch size, suggesting that species interactions regulate the collapse of avian diversity in human-modified forests. I conclude that land-use change has important implications for the provisioning of ecosystem services, including seed dispersal and the control of insect herbivores. The impact of future land-use change is likely to be mediated by the composition of the original pool of species and the amount of redundancy in the ecosystem services that they provide. I discuss the relevance of my findings to land-use management strategies and policy interventions, and in particular conclude that these should, where possible, maintain pristine forest patches above 1000 ha, improve connectivity among habitat patches, and ensure greater protection for logged and burnt forests. Future studies should focus on clarifying the link between shifts in vertebrate community structure and the functioning of forest ecosystems.

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Liu, Ziming. "Understanding the Land Cooperative Program in China: Determinants and Impact." Doctoral thesis, Humboldt-Universität zu Berlin, 2017. http://dx.doi.org/10.18452/18581.

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Diese Doktorarbeit trägt durch eine Analyse der chinesischen Landgenossenschaften zum Verständnis von Politik und Prozessen im Ko-Management natürlicher Ressourcen bei. Im Mittelpunkt dieser Arbeit steht die Frage wie der lokale Kontext und Haushaltscharakteristika mit der Implementierung von Landgenossenschaften interagieren. Ich adressiere diese Frage in drei empirischen Forschungsartikeln. Im ersten Artikel untersuchen ich die Wirkung verschiedener lokaler Kontextvariablen in verschiedenen Dörfern auf den Anteil der Landflächen, der von einer Landgenossenschaft verwaltet wird. Es wird gezeigt, wenn lokale Eliten, wie Regierungsbeamte, Dorfkader oder gebildete Menschen, Genossenschaftsvorsitzende sind, ist der Anteil von Land, der an die Genossenschaft übertragen wird, deutlich größer. Im zweiten Artikel wenden ich uns der Haushaltsebene zu und untersuchen Bestimmungsfaktoren der Mitgliedschaft in einer Genossenschaft und die Auswirkungen der Mitgliedschaft auf die Allokation der verfügbaren Arbeitskraft. Ich stelle keinen allgemeinen Effekt von Genossenschaftsmitgliedschaft auf die Wahrscheinlichkeit der außerlandwirtschaftlichen Berufstätigkeit des Haushaltsvorstandes fest. Im dritten Artikel analysieren ich, wir den Zusammenhang zwischen Partizipation in Entscheidungsprozessen und Haushaltseinkommen aus Landgenossenschaften. Ich zeige, wohlhabendere Mitglieder und solche mit Mitgliedschaft in der kommunistischen Partei haben eine höhere Wahrscheinlichkeit an Entscheidungsprozessen teilzunehmen. Genossenschaftsmitglieder weniger von ihrer Mitgliedschaft profitieren, wenn sie nicht in Entscheidungsprozesse involviert sind. Zusammenfassend zeigt diese Dissertation, dass der lokale Kontext einen Unterschied in der Implementierung von Landgenossenschaften macht. Um die Genossenschaften zu fördern sollten politische Entscheidungsträger die Heterogenität der lokalen Bevölkerung.
This thesis contributes to the understanding of politics and processes in the co-management of natural resources through an analysis of Chinese land cooperatives. The focus of this work is the question of how local context and household characteristics interact with the implementation of land cooperatives. I address this question in three empirical research articles. In the first article, I examine the effect of different local context variables in different villages on the share of land area managed by a rural cooperative. It is shown that when local elites, such as government officials, village cadres or educated people, are co-operative chairmen, the proportion of land transferred to the cooperative is significantly larger. In the second article, I turn to the household level and examine determinants of membership in a cooperative and the impact of membership on the allocation of available labor. I do not state any general effect of cooperative membership on the probability of the head of household's non-agricultural employment. In the third article, I analyze the connection between participation in decision-making and household income from land cooperatives. I show that wealthier members and members of the Communist Party are more likely to participate in decision-making. Cooperative members benefit less from their membership if they are not involved in decision-making. In summary, this dissertation shows that the local context makes a difference in the implementation of land cooperatives. To encourage cooperatives, policy makers should consider the heterogeneity of the local population.

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le, Brasseur Richard. "Transitional landscapes : examining landscape fragmentation within peri urban green spaces and its impacts upon human wellbeing." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31257.

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Transitional land uses produced through urbanisation continue to change the landscape and fragment ecological structures including green spaces across Europe (Nilsson et al., 2013). Green spaces offer significant benefits to humans, contributing to wellbeing and life satisfaction (Taylor, 2002). The understanding of how these unique green spaces spaces function and provide benefits to humans, and how landscape change in peri-urban contexts affects their performance, is important. The scope of this research is to contribute to an understanding of landscape fragmentation within some of Europe's polycentric urban regions, their peri-urban green spaces, and the associated impacts upon human quality of life. Two urban regional case studies, Paisley near Glasgow, Scotland, and Vantaa, near Helsinki, Finland were analysed and compared. The results indicate that humans interacting with more physically or ecologically fragmented peri-urban green spaces have higher self-reported life satisfaction levels. Though no statistically significant characteristics were apparent between life satisfaction and fragmented green space characteristics, this research was able to identify those specific structural attributes and physical characteristics of interstitial peri-urban green spaces within a polycentric region in a fragmented state that contribute to the physical, social, and psychological aspects of human wellbeing. The statistically significant eco-spatial characteristics of polycentric peri-urban interstitial green spaces that are reported to impact human wellbeing are the size, proximity, maintenance and management, and the level of greenness within its vegetation composition and setting. Overall, a spatially diverse, fragmented, peri-urban landscape whose green spaces are extensively sized, naturalistically shaped with horizontal vegetation and normal sized edges, most often parks or woodlands or forests which are integrated and physically connected to another green space which is moderately clean and somewhat safe as well as being located close to or adjacent to a heavy-trafficked road provide the most human wellbeing benefits.

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Kim, Jin Ki. "Exploring the effects of local development regulations on ecological landscape structure." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2403.

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An ecological approach to land-use planning is essential to maintain the long-term sustainability of ecosystem benefits, services, and resources. Concern about environmental quality and the long-term livability of urban areas is now a driving force in urban planning and design. The interrelated issues of growth management, smart growth, sustainable development, and new urbanism are topics in the most vibrant discussions at all levels of planning and landscape architecture. Within this context, this study starts from the interest in the ecological planning and management in urban areas, especially related to the issue of local development regulation and guidelines. Landscape regulations have come into existence recently in communities across the nation and these regulations vary from one region to another and from one community to another. The aims of this study were to investigate the relationship between ecological landscape structure and local development regulations over time. Comparison analysis was conducted between two areas that had similar pre-development ecological conditions but were developed under vastly different regulatory environments. The Woodlands (regulated to protect ecological condition) and the North Houston area (which followed traditional subdivision regulations) were examined at three different developmental time periods: predevelopment, early development (after 10 years), and matured development (after 30 years). Aerial photos of each site from the three time periods were classified into forested and non-forested classes and the landscape structure was quantified with a number of landscape metrics related to fragmentation??an indicator of habitat degradation. Two factors, the ecological approach to landscape planning and the adoption of more restrictive landscape regulations and guidelines, are discussed on the premise that they exert influence in developing and maintaining the long-term sustainability of ecosystems. In conclusion, this study provides the quantified landscape configuration and composition of the effects of development regulations on landscape structure. The ecologically planned community shows a less fragmented forest pattern and more restrictive development guidelines result in more ecologically structured environments. Understanding how elements of local development regulations affect ecological landscape patterns is important for landscape architects, planners, and administrators because it can lead to better strategies for planning and designing sustainable communities.

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Gilleland, Amanda H. "Human-Wildlife Conflict Across Urbanization Gradients: Spatial, Social, and Ecological Factors." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3489.

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As suburban and exurban residential developments continue to multiply in urban areas, they encroach on wildlife habitats leading to increased human-wildlife interactions. The animals involved in direct conflict with homeowners are often relocated or exterminated by the homeowners. Often the homeowners contact state licensed wildlife trappers to eliminate the problem animal. In this study I examined how landscape, ecological, and social factors influence the incidence of human-wildlife conflict of thirty two residential areas in the Tampa, Florida metropolitan area. These residential areas, totaling over 300 km2, are part of the urban development gradient representing a range of urban land use from the urban core to exurban residential areas. This study consisted of four phases. In the first three phases, I investigated which landscape, ecological, and social factors contribute to homeowner conflict with wild animals on their property. In the last phase, I combine the significant factors contributing to human-wildlife conflict from the first three phases to build a more complete model. A spatial analysis of the locations of human-wildlife conflict events recorded by licensed wildlife trappers showed the most significant development and landscape factors affecting human-wildlife conflict reporting in a residential area were human population density and total area of natural habitat immediately adjacent to the residential area. A survey of the relative abundance of conflict prone animals living near and in remnant patches of habitat in suburban residential areas revealed that greater abundance was not correlated with the reported conflict of that species within that residential area. Species that were social, omnivorous, and had some flexibility in home range size were involved most often in conflict in highly urbanized environments. Species that were less social, and were not omnivorous, were not significantly involved in human-wildlife conflict in highly urbanized residential areas. These species tended to be restricted to intermediately urbanized areas like suburban and exurban residential areas. Several social factors were also significant contributors to human-wildlife conflict as revealed through personal interviews with suburban homeowners in Hillsborough and Pasco counties. Interviews confirmed that most people have positive attitudes toward wildlife, but some form of conflict was reported by thirty four percent of suburban residents, although only seventeen percent of those perceived it as a problem worth spending money to solve. Analysis of the attitudes of residents who reported having experienced problems associated with wildlife on their property, revealed significant negative correlations with statements of environmental concern and concern for the treatment of animals. Using all the significant variables from the physical landscape, ecological evaluation, and the human attitude study in the suburbs, I developed a statistical model of human-wildlife conflict across the urbanization gradient. While the model has marginal success in terms of practical application for prediction, it is quite valuable for defining the importance of these variables in relation to conflict with certain types of species across the gradient. This set of papers collectively defines relationships between variables existing in urban, suburban, and exurban residential areas and human-wildlife conflict. These factors should be considered when planning new residential areas to minimize human-wildlife conflict while maximizing the residents’ enjoyment of natural areas and species within the residential area.

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McClure, Meredith L., Brett G. Dickson, and Kerry L. Nicholson. "Modeling connectivity to identify current and future anthropogenic barriers to movement of large carnivores: A case study in the American Southwest." WILEY, 2017. http://hdl.handle.net/10150/624692.

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This study sought to identify critical areas for puma (Puma concolor) movement across the state of Arizona in the American Southwest and to identify those most likely to be impacted by current and future human land uses, particularly expanding urban development and associated increases in traffic volume. Human populations in this region are expanding rapidly, with the potential for urban centers and busy roads to increasingly act as barriers to demographic and genetic connectivity of large-bodied, wide-ranging carnivores such as pumas, whose long-distance movements are likely to bring them into contact with human land uses and whose low tolerance both for and from humans may put them at risk unless opportunities for safe passage through or around human-modified landscapes are present. Brownian bridge movement models based on global positioning system collar data collected during bouts of active movement and linear mixed models were used to model habitat quality for puma movement; then, a wall-to-wall application of circuit theory models was used to produce a continuous statewide estimate of connectivity for puma movement and to identify pinch points, or bottlenecks, that may be most at risk of impacts from current and future traffic volume and expanding development. Rugged, shrub- and scrub-dominated regions were highlighted as those offering high quality movement habitat for pumas, and pinch points with the greatest potential impacts from expanding development and traffic, although widely distributed, were particularly prominent to the north and east of the city of Phoenix and along interstate highways in the western portion of the state. These pinch points likely constitute important conservation opportunities, where barriers to movement may cause disproportionate loss of connectivity, but also where actions such as placement of wildlife crossing structures or conservation easements could enhance connectivity and prevent detrimental impacts before they occur.

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Tripathi, Hemant Gangaprasad. "Biodiversity of the African savanna woodlands : how does it change with land use?" Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/28965.

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The savanna woodlands of Southern Africa, colloquially termed the miombo, are poorly described in terms of biodiversity compared to other biomes. They have therefore been underrepresented in the wider understanding of how land use intensification is shaping global biodiversity. Land use change is known to reduce biodiversity and disrupt intactness of ecological communities with consequences for ecosystem functioning, resilience, and services. Miombo woodlands are described as biodiversity hotspots due to a high endemism of species and the presence of megafauna. At the same time, they are also considered dynamic socio-ecological systems shaped by disturbances and the land use activities of people. The patterns of biodiversity change in these tropical ecosystems may, therefore, have their own unique contexts, understanding of which will be essential for biodiversity and land use management in these ecosystems. In this thesis, I identified the patterns of biodiversity change in response to the two major land use practices in the two dominant woodland types in southern African woodlands: the selective logging due to charcoal production in the mopane woodlands, and agricultural expansion in the miombo. I also examined the impact of two main disturbance agents, humans and elephants, on habitat structure and biodiversity in mopane woodlands. Across all chapters in this thesis, I investigated the effects of land use change and habitat modification on biodiversity empirically using chronosequences. To understand biodiversity change, I employed a hierarchical multilevel modelling approach making inferences at the three levels of ecological communities: species, community, and meta-community (set of ecological communities at different sites). I selected six villages in the charcoal production hotspot of southern Mozambique and carried out field surveys for three taxonomic groups: trees, mammals and ground beetles. I modelled the counts of trees and beetles and incidence of mammals using meta-community occurrence models in a Bayesian framework with the intensity class of the villages, above-ground biomass and land cover type as predictors. The results suggested that the species richness of trees and mammals declined by 12 and 8.5 % respectively while that of beetles increased by 3.5%, albeit non-significantly. In addition, the beta diversity of trees decreased while that of mammals increased. The results show that while both trees and mammals reduced in richness, they responded differently to charcoal production in terms of community organisation. The trees underwent subtractive homogenisation (decrease in alpha and beta diversities) primarily because of deterministic processes induced by selective harvesting of tree stems for charcoal. Mammal communities, on the other hand, showed subtractive heterogenization (decrease in alpha, but increase in beta diversity) mainly due to random extinctions. In the agriculture frontier of miombo-dominated northern Mozambique, I investigated the effects of fragmentation and habitat loss caused by agricultural expansion on diversity and composition of trees and mammals. I modelled the occurrences of trees and mammals using occupancy models with the fragmentation and quantity of woodland cover as predictors. The model showed that most tree species (n=10), mainly the timber and firewood species, linearly declined in population size as fragmentation increased. Mammals, on the other hand, showed a nonlinear response. Seven mammal species increased at the lower levels of fragmentation. However, at the higher levels, none of the mammal species increased while two declined. Similarly, the species richness of trees linearly declined, while that of mammals increased up to a fragmentation level of 55-65% and declined above this limit. The beta diversity of trees increased with fragmentation while that of mammals decreased. The results suggest that, although fragmentation reduces species richness of both trees and mammals, it affects their species compositions in different ways. Trees undergo subtractive heterogenization due to random species losses while mammals experience subtractive homogenisation mainly due to the combined effects of fragmentation-led habitat loss and intensified hunting. Finally, this study concludes that, above 75% fragmentation or below 26% habitat quantity, both taxonomic groups endure biodiversity loss. The threshold results here corroborate similar habitat quantity thresholds (20-30%) observed elsewhere in different ecosystems. However, they differ with the widespread notion that above 30% habitat quantity, the effect of fragmentation is non-existent. The results here emphasize that taxonomic groups respond differently, the diversity and population size of mammals reduced only after the habitat threshold, whereas, those of trees showed linear decrease with fragmentation most likely due to fragmentation-led habitat loss. Lastly, I examined the effects of disturbance by humans and elephants on habitat structure and bird diversity by conducting a space for time substitution comparison in the mopane woodlands of Zambia. To examine the woodland structure, I modelled the structural attributes of habitat (stem diameter, stand density, and basal area) using mixed models with the proportion of affected stems by humans and elephants as explanatory variables. I found that elephant disturbance was associated with higher stem diameters, low stand densities, but no change in basal area. Human disturbance, on the other hand, was related to reductions in stand density and basal area, but no change in the stem diameter. Further, I tested species and functional diversity of birds against the covariates of habitat structure and disturbance. I found that bird communities reduced in species richness in both, human as well as elephant disturbed areas. However, the functional diversity did not change with elephant disturbance. I concluded that human disturbance reduces woody biomass (basal area is correlated with woody biomass) of mopane woodlands and functional diversity of birds whilst elephants do not. In this thesis, I conclude that human driven land use change in the miombo woodlands erodes alpha diversity of all taxonomic groups. However, increases in beta diversity of mammals with charcoal land use and trees in agricultural land use may maintain their diversities at the meta-community level.

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Li, Zhichao. "Modélisation des relations entre occupation - usage du sol et distribution spatiale du paludisme par télédétection optique et radar : application à un environnement en évolution : région transfrontalière Guyane Française – Brésil." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT144/document.

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Le paludisme est un des maladies vectorielles les plus communes qui est situé principalement dans les régions tropicales. La zone étudiée est la région transfrontière Guyane française-Brésil. Le niveau et la dynamique intra-annuelle de la transmission y sont variables, avec un taux d’incidence qui est relativement élevé dans l’Amérique du Sud. Les facteurs environnementaux, en particulier l'occupation et l'usage du sol, influent significativement sur la présence, la densité et la distribution spatiale des moustiques du genre Anophèles, vecteurs de la maladie. Les données sur l'environnement, la population et les systèmes de santé sont rarement comparables de part et d’autre de la frontière Guyane-Brésil, excluant une vision bilatérale homogène. La télédétection permet de caractériser spatialement l’environnement de manière quasi continue et complète. L’objectif de ce travail est de caractériser par télédétection des milieux favorables au développement des vecteurs et les interactions hommes-vecteurs pour la zone transfrontalière Guyane-Brésil. Un indicateur spatialisé d’aléa de transmission du paludisme a été développé à l’échelle locale. Il permet de spatialiser la contribution de l'interaction entre milieux forestiers et non-forestiers sur la transmission du paludisme. Ce modèle a été mis en œuvre à l’échelle de la région amazonienne. Cet indice permet de quantifier et d’expliquer l’influence du paysage dans les interrelations homme - vecteurs adultes. L’identification des gîtes larvaires potentiels a été testée à une échelle régionale, à partir de la fusion d’images satellites optiques et radar, afin de mettre en évidence la distribution spatiale de zones humides pérennes et de grandes tailles (lacs, rivières, étangs, etc.) et les interfaces avec les milieux urbaines et forestiers. La distribution et la densité des vecteurs sont affectées par les propriétés physiques et chimiques des gîtes larvaires potentiels qui sont liées à la typologie des sols. Un modèle conceptuel de l’évaluation des sols adapté à la zone amazonienne présente que les caractéristiques géomorphologiques (altitude, courbure, etc.) sont indicateurs de l’évolution des sols. Une typologie des sols a été réalisée à l’échelle régionale à partir de données altimétriques et de ce modèle conceptuel. Les méthodologies, les cartes d’occupation et d’usage du sol, les cartes d’aléa du paludisme mises en place dans le cadre de cette thèse seront intégrés à l’Observatoire transfrontalier (Guyane-Brésil) qui est en cours de création. Ce travail de thèse contribue ainsi à l’exploitation des nouvelles connaissances sur le mécanisme de transmission du paludisme qui peuvent être utilisées pour définir les nouvelles stratégies de prévention aux échelles locale et régionale
Malaria remains one of the most common vector-borne diseases what is predominantly located in the tropics. The study area is the cross-border area between French Guiana and Brazil where the level and intra-annuel dynamic of malaria transmission are variable, with the incidence rates which are relatively high in South America. The environmental risk factors, in particular, land use and land cover, significantly influence the presence, density and spatial distribution of disease vectors, Anopheles mosquitoes. Environmental information, population data and health systems database are rarely comparable on both sides of the Guyana-Brazil border which exclude the homogeneous and bilateral vision. Remote sensing permits to spatially characterize the environment on both sides of the border in an almost continuous and complete manner. The objective of this study is to characterize the favorable environment for the development of vectors and the vector-human interaction in the cross-border area between French Guiana and Brazil using remote sensing. A spatial landscape-based hazard index of malaria transmission was developed at the local scale. Such index allows spatializing the contribution of interaction between forest and non-forest areas on malaria transmission which was then implemented in the entire Amazon region. It quantifies and explains the influence of landscape on the interaction between human population and adult vectors. The identification of potential breeding sites of vectors was tested on a regional scale using the optical and SAR fusion for highlighting the spatial distribution of perennial and large wetlands (lakes, rivers, ponds etc.) and the interfaces with urban and forest environments. The distribution of vectors’ density is affected by physical and chemical properties of potential breeding sites which are related to soil typology. A conceptual model of soil evolution adapted to the Amazon region presents that geomorphological characteristics (altitude, curvature, etc.) are indicators of soil evolution. A soil classification was realized at the regional scale using altimetry data and the conceptual model. The methods, land use and land cover and malaria hazard maps established in this thesis will be integrated in the Observatory Sentinel of cross-border which is being built. This study also contributes to the exploitation of new knowledge about malaria transmission mechanism which can be used to define novel prevention strategies at the local and regional scales

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Dunn, Ingrid. "Structure, Composition, and Regeneration of Cross Timbers Forest Fragments in Different Land Use Contexts." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc799466/.

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Throughout its current range, the Cross Timbers forest ecosystem is vulnerable to land-use change. In this study, we examined the surrounding land use matrix on the vegetation structure, composition and regeneration of six Cross Timbers forest fragments in Denton County, Texas (north of the Dallas-Fort Worth metroplex). Two fragments adjacent to agricultural land, two to residential neighborhoods, and two formally protected forest sites were selected. In summer 2015, five 100 m2 plots were randomly established in each fragment at least 200 meters from the edge. In each plot, all live and dead trees ≥ 3 cm diameter were identified and their height and diameter at breast height (DBH at 1.3 m aboveground) measured. Evidence of dumping (presence of trash) was recorded as an index of human frequentation. Differences in vegetation structure among the forest fragments were found. Most notably, fragments adjacent to agriculture contained 25% to 50% fewer trees per hectare than all other sites (Kruskal-Wallis, p < 0.02), especially trees <10 cm DBH. However, residential fragments had fewer trees that were ≥15 cm DBH compared to the other fragments, indicating that these are the youngest of the forest patches surveyed. Trash was observed in 60% of plots surveyed at residential forest sites, showing high levels of human frequentation compared to the protected and agricultural forest sites. Agricultural sites contained the lowest number of recorded tree species and were most similar to each other, sharing 91% of species. These findings indicate that surrounding land use affects forest structure and composition, consequently affecting valuable ecosystem services including wildlife habitat, aesthetics and recreation.

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Kümmerle, Tobias. "Post-socialist land use change in the Carpathians." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2008. http://dx.doi.org/10.18452/15741.

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Politische und sozioökonomische Rahmenbedingungen haben entscheidenden Einfluss auf Landnutzungswandel; die relative Bedeutung dieser Faktoren untereinander ist jedoch oftmals unklar. Ziel dieser Arbeit ist es, durch die Untersuchung der Auswirkungen der politischen und sozioökonomischen Transformation auf Landnutzungswandel in Osteuropa zu einem besseren Verständnis solcher übergreifenden Einflussfaktoren beizutragen. Am Beispiel des Dreiländerecks Polen-Slowakei-Ukraine in den Karpaten wurden hierzu grenzüberschreitende Landschaftsvergleiche durchgeführt, da solche Vergleiche die Entkopplung der Faktoren allgemeiner Landnutzungstrends von Faktoren länderspezifischer Veränderungen ermöglichen. Darüber hinaus sind die Auswirkungen postsozialistischen Landschaftswandels auf die Karpaten, einem Gebiet mit einzigartigem ökologischen Wert, bisher weitestgehend unerforscht. Mit Hilfe von Landsat TM/ETM+ Satellitendaten aus dem Jahr 2000 wurden rezente Landschaftsunterschiede zwischen Ländern quantifiziert. Auf der Basis von Bildern von 1986-2000 wurde anschliessend überprüft, ob Länderunterschiede auf sozialistischen oder post-sozialistischen Landschaftswandel zurückführbar sind. Die Ergebnisse dieser Analysen zeigten weit verbreiteten Landnutzungswandel nach 1989 als Folge von sich verschlechternden wirtschaftlichen Bedingungen, geschwächten Institutionen und gesellschaftlichem Wandel. Die Länder unterschieden sich jedoch auch deutlich hinsichtlich Forstveränderungen, Brachfallung und Parzellierung von Ackerland. Diese Unterschiede lassen sich durch verschiedene Besitzverhältnisse, Bewirtschaftungsformen und Landreformen erklären. Während sich Polen und die Slowakei landschaftlich seit 1989 annähern, entfernt sich die Ukraine zunehmend. Diese Arbeit unterstreicht die Bedeutung ökonomischer und institutioneller Veränderungen für Landschaftswandel und zeigt, wie unterschiedliche Besitzstrukturen und Landreformen Landschaftswandel beeinflussen.
Broad-scale political and socio-economic conditions are powerful determinants of land use change. Yet, their relative importance is unclear. The main goal of this thesis was to increase the understanding of such broad-scale drivers of land use change by studying how Eastern Europe’s landscapes were affected by the political and socio-economic transition after the fall of the Iron Curtain in 1989. The border triangle of Poland, Slovakia, and Ukraine in the Carpathians was selected as a study area, because cross-border comparisons of land use change allow for decoupling overall trends in the transition period from country specific changes. Moreover, the Carpathians are of exceptional ecological value, but little is known about land use effects on these ecosystems after 1989. Post-socialist land use change was quantified based on Landsat TM/ETM+ images by (1) comparing contemporary (year 2000) landscapes among countries, and (2) using images from 1986 to 2000 to investigate whether differences originated from socialist or post-socialist land use change. Results indicated that forest change, farmland abandonment, and farmland parcelization were widespread in the transition period, likely due to worsening economic conditions, weakened institutions, and societal change. However, land use trends also differed strongly among the three countries due to dissimilar land ownership patterns, land management practices, and land reforms. Poland and Slovakia converged in the transition period in terms of land cover, while Ukraine clearly diverged. This thesis provided compelling evidence of the importance of economic and institutional change for land use change and underpinned the pivotal role of ownership patterns and land management policies. These factors were important to understand land use change in Eastern Europe, and they are likely equally important elsewhere.

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Pereira, Heloisa Helena Gianotti. "CONEXÃO ENTRE FRAGMENTOS DE VEGETAÇÃO COM BASE EM SISTEMAS DE INFORMAÇÕES GEOGRÁFICAS." UNIVERSIDADE FEDERAL DA GRANDE DOURADOS, 2010. http://tede.ufgd.edu.br:8080/tede/handle/tede/128.

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One of the connection form between fragments of vegetation, the ecological corridor, it s one of the strategies for biodiversity conservation and in the course of the decision on its localization, Geographic Information Systems (GIS) can contribute as an effective supportive tool to this process. In this context, this study was developed as a methodology to allow the definition of paths for ecological corridors, giving priority to the connection of remaining vegetation, based on low cost GIS. Dourados river basin was taken as a case study, located in southern Mato Grosso do Sul, with great regional importance and a high level of deforestation. Using the GIS Spring, Idrisi and GRASS, at different times, a map of the Land Use Basin from Landsat 5-TM, March-April 2008, was generated, as well as various plans of information (PI), distinguishing such uses. These P.I. were superimposed using a File Values of Friction associated with the uses, thus generating a surface of friction. The PI containing the simulated corridors points of exit was conjugated with the Surface Friction, resulting in a Cost Surface for each, which, in turn, associated with the arrival PI resulted in the definition of corridors routes. Measurements were taken and the creation of the buffer of 120m side of the each line of trajectory, totalizing 240m. Besides the main corridor, which followed the axis of Dourados River, seven others secondary corridors were simulated, all of which followed the drainage lines, diverting away from them when meeting with arrangements of use with high friction, or being attracted to those with a degree far from its own, proving the efficiency of the methodology adopted. In the layout of the secondary corridors was found a significant overlap with the path of the main corridor, demonstrating that along the banks of Dourados River and in its immediate surrounding area were concentrated most of the areas with the lowest cost for the implementation of an ecological corridor. Due to the level of deforestation of the basin, the layouts of the eight corridors involved farming areas in less than 20%, except two of them. Simulating the implementation of the eight units and considering the total area of the municipalities within the basin, none of them was over the limit of 0.40% of its area under agricultural activity. The expansion of the corridors may occur with the inclusion of permanent preservation areas (PPA) in its entirety and not just in the range of 240 m band, and of areas occupied by vegetation and lowland forest fragments derived from the legal reserve. Thus, the methodological procedure developed was proven to be valid for a preliminary definition of the trajectory of the ecological corridors, favoring larger and more circular fragments, in addition to permanent preservation areas and lowlands, as well as it demonstrated its facility for the inclusion or exclusion of variables in the course of the review process. In addition to these aspects, the use of free satellite images by INPE and the use of GIS with a low or no cost may turn this procedure into a useful tool in the definition of conservation strategies
Uma das formas de conexão entre fragmentos de vegetação, o corredor ecológico, constitui-se em uma das estratégias para a conversação da biodiversidade e, no transcorrer da tomada de decisão sobre sua localização, os Sistemas de Informações Geográficas (SIGs) podem contribuir como ferramenta efetiva de apoio a esse processo. Nesse contexto, o presente trabalho teve como objetivo desenvolver metodologia que possibilitasse a definição de trajetos para corredores ecológicos, privilegiando a conexão de remanescentes de vegetação, utilizando SIG de baixo custo. Como estudo de caso foi tomada a bacia do Rio Dourados, localizada no Sul de Mato Grosso do Sul, com grande importância regional e elevado nível de desflorestamento. Utilizando-se os SIG Spring, Idrisi e GRASS, em diferentes momentos, gerou-se o Mapa de Uso da Terra da bacia, a partir de imagens Landsat 5-TM, de março-abril de 2008, assim como vários planos de informação (P.I.), individualizando tais usos. Esses P.I. foram sobrepostos e, utilizando-se um Arquivo Valores de Atrito associados aos usos, gerou-se uma Superfície de Atrito. O P.I. contendo os pontos de saídas dos corredores simulados foi conjugado à Superfície de Atrito, resultando em uma Superfície de Custo para cada um, a qual, por sua vez, associada ao P.I. de Chegada, resultou na rota dos corredores. Foram realizadas as mensurações e criação do buffer de 120 m de cada lado da linha de trajetória, totalizando 240m. Além do corredor principal, que seguiu o eixo do Rio Dourados, foram simulados mais sete corredores secundários, sendo que todos acompanharam as linhas de drenagem, afastando-se delas quando do encontro com modalidades de uso com elevado grau de atrito, ou sendo atraídas por aquelas com menor, comprovando a eficiência da metodologia adotada. No traçado dos corredores secundários constatou-se uma significativa sobreposição com o trajeto do corredor principal, demonstrando com isso que junto às margens do Rio Dourados e em seu entorno imediato se concentra a maior parte das áreas com o menor custo para a implantação de um corredor ecológico. Devido ao nível do desflorestamento da bacia, os traçados dos oito corredores atingiram áreas com agropecuária em menos de 20%, exceto dois deles. Simulando a implantação das oito unidades e considerando a área total dos municípios que compõem a bacia, em nenhum deles é ultrapassado o limite de 0,40% de sua superfície ocupada com atividade agropecuária. A ampliação dos corredores pode ocorrer com a inclusão das áreas de preservação permanente (APP) em sua totalidade e não só na faixa de 240 m de largura, assim como das áreas ocupadas com vegetação de várzea e fragmentos de mata oriundos de reserva legal. Dessa forma, constatou-se que o procedimento metodológico desenvolvido é válido para a definição preliminar da trajetória de corredores ecológicos, privilegiando fragmentos maiores e mais circulares, além de áreas de preservação permanente e várzeas, assim como possui facilidade para a inclusão ou exclusão de variáveis no transcorrer do processo de análise. Dessa forma, a utilização de imagens de satélite disponibilizadas gratuitamente pelo INPE e o uso de SIG de baixo ou nenhum custo podem tornar tal procedimento um instrumento útil na definição de estratégias conservacionistas.

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Pina, Gabriela Ferracine de. "Análise multicritério na identificação de áreas para a recuperação ecológica no plano de manejo ambiental municipal." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/152440.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Recuperação ecológica é a restituição de um ecossistema degradado a uma condição não degradada. É uma importante estratégia para reverter os reflexos negativos na conservação da biodiversidade, o que caracteriza a importância da determinação da localização de ambientes que podem ocorrer essa recuperação. O trabalho objetivou identificar as áreas passíveis de recuperação ecológica e potenciais para a implantação de corredores ecológicos, no município de Sertãozinho - SP, com o intuito de aumentar as funções ecológicas dos fragmentos e auxiliar no planejamento de manejo ambiental municipal. A declividade, as áreas de preservação permanente, o uso e a ocupação do solo e os fragmentos de vegetação natural do município foram calculados e mapeados usando técnicas de geoprocessamento. Para cada mapa base obtido, uma amplitude de valores de apoio à tomada de decisão foi determinada, por meio do método estatístico de análise multicritério (Análise Hierárquica de Processos- AHP), o que possibilitou a hierarquização das variáveis mapeadas, com ênfase na importância e nas alternativas que se encontram e no conjunto de indicadores que definem as áreas prioritárias à recuperação ecológica, tanto em áreas de preservação permanente, como em reservas legais, na forma da lei vigente. Os mapas das áreas indicadas à recuperação e das áreas potenciais para a implantação de corredores ecológicos resultaram da álgebra dos mapas base. A distribuição espacial dos fragmentos de vegetação natural na paisagem do município é aleatória e fragmentada, sob alto efeito de borda. Sugere-se a recuperação ecológica de 8.062 ha em áreas no entorno dos fragmentos existentes (áreas de amortecimento) e ao longo da rede de drenagem, bem como a implantação de corredores ecológicos (20,92 ha) na porção sudoeste do município. Os resultados obtidos permitem compor e enriquecer o Plano Diretor de Sertãozinho, dando direcionamento e aprimoramento ao planejamento, à gestão e à fiscalização ambiental do município.
Ecological recovery is the restitution of a degraded ecosystem to a non-degraded condition. It is an important strategy to reverse negative impacts on biodiversity conservation, which characterizes the importance of determining the location of environments that can be recovered. The objective of this work was to identify the ecological and potential ecological recovery areas in the city of Sertãozinho, SP, in order to increase the ecological functions of the fragments and to assist municipal environmental management planning. The slope of the areas, the permanent preservation areas, the land use, and the fragments of natural vegetation of the municipality were calculated and mapped using geoprocessing techniques. For each base map obtained, an amplitude of values to support decision making was determined through the analytic hierarchy process (AHP) in a structured technique for organizing and analyzing decisions do recover the environment. The statistical method allowed the hierarchy of mapped variables, with emphasis on importance and alternatives that make a set of indicators that define the priority areas for ecological recovery, both for permanent preservation areas and for possible legal reserves areas, to adequate the land to the current law. The maps of the areas indicated for recovery and the potential areas for the implantation of ecological corridors resulted from the algebra of the base maps. The spatial distribution of fragments of natural vegetation in the municipality landscape is random and fragmented, under high edge effect. It is suggested the ecological recovery of 8,062 ha in areas around the existing fragments (damping areas) and along the drainage network, as well as the implantation of ecological corridors (20.92 ha) in the southwest portion of the municipality. The results obtained allow us to compose and enrich the Sertãozinho Master Plan, giving direction and improvement to the planning, management and environmental control of the municipality.

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Chisingui, António Valter. "Análise da paisagem e das alterações de uso/ocupação do solo no Lubango e arredores." Doctoral thesis, Universidade de Évora, 2017. http://hdl.handle.net/10174/20708.

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A cartografia temática surge como um aliado indispensável ao estudo e conhecimento do estado da paisagem e dos ecossistemas terrestres. Angola é um país com uma enorme lacuna em termos de informação cartográfica para suporte a diversas actividades desenvolvidas em várias áreas. É por isso necessária informação sobre a superfície terrestre que registe as alterações temporais ocorridas nos ecossistemas e identifique os factores que estão na sua origem de forma a implementar medidas que permitam uma gestão mais sustentável do seu enorme território. O presente estudo foi realizado no sector Sudoeste de Angola, abrangendo os municípios do Lubango, Humpata e Chibia, com uma área aproximada de 9600 km2. Os objectivos foram: a) cartografar o coberto do solo e monitorizar as alterações ocorridas na área de estudo no período 1990-2010, b) analisar e interpretar as alterações da estrutura da paisagem nos últimos 20 anos usando cartografia de ocupação do solo, produzida recorrendo a imagens de satélite, e métricas da paisagem, e c) quantificar e examinar a relação entre a fragmentação da paisagem e os factores geradores. A metodologia utilizada no estudo é composta por duas partes, sendo a primeira dedicada às operações de processamento e interpretação de imagens de satélite Landsat e, a segunda dedicada à produção de novas métricas de fragmentação da paisagem com recurso à ferramenta SIG utilizando operações de álgebra de mapas. O comportamento da fragmentação é analisado, à luz do efeito dos fatores ambientais e socioeconómicas ao nível da região. Os resultados obtidos, através da aplicação de técnicas de deteção remota e usando imagens Landsat TM e ETM+, permitiram a elaboração de mapas de coberto do solo, onde se distinguiram 8 classes temáticas e espectralmente diferentes. Verificou-se em termos globais que aproximadamente 38% da área sofreu algum tipo de alteração no período estudado, sendo as classes de miombo e áreas cultivadas as que mais alterações sofreram. A fragmentação da paisagem foi avaliada através da implementação de novas métricas, mostrando os resultados, que no período 1990-2000, a fragmentação foi superior à que se verificou entre 2000-2010. A nível espacial, a dinâmica de fragmentação foi mais acentuada, entre 1990-2000, na Humpata e, entre 2000-2010, no Lubango; ANALYSIS OF LANDSCAPE AND LAND USE LAND COVER CHANGE IN LUBANGO AND SURROUNDINGS ABSTRACT: Thematic cartography shows up as an essential ally in the study and knowledge of the state of landscapes and terrestrial ecosystems. Angola is a country with an enormous lack of cartographic information to support the several activities carried out in a variety of areas. This is the reason information on the earth’s surface is necessary, registering alterations which occur over time in ecosystems and identifying the associated factors in its origin, so as to implement metrics that allow a more sustainable management of its enormous territory. This study was carried out in the Southeast of Angola in the Lubango, Humpata and Chibia Municipalities, with an area of approximately 9600 km2. Our objectives were the following: a) land cover mapping and land cover changes monitoring over the period 1990 to 2010 using Landsat images, b) to analyze and interpret landscape structures changes using land cover maps, and landscapes metrics, and c) to quantify and to examine the relationship between landscape fragmentation and its drivers. The methodology developed in the study has two parts, the first includes Landsat satellite images processing and interpretation and, the second the production of new landscape fragmentation metrics with support to a GIS tool and algebraic mapping operations. The fragmentation behavior is analyzed, taking into account the effect of environmental and socioeconomic factors at a regional level. The results allowed obtaining land cover maps, in which 8 spectrally different thematic classes were distinguished. It was observed that 38% of the area suffered some type of alteration in the studied period, with higher changes observed in the classes of miombo and agriculture. Landscapes fragmentation results, evaluated through the implementation of new metrics, show that, values are greater in the period 1990-2000 than in 2000-2010. At municipality level, fragmentation dynamics were more accentuated in Humpata between 1990 -2000 and in Lubango between 2000 -2010.

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Khansaritoreh, Elmira [Verfasser], Markus [Akademischer Betreuer] Hauck, Edmone [Gutachter] Roffael, and Christoph [Gutachter] Leuschner. "Effects of Land Use, Habitat Fragmentation and Climate Warming on Stem Increment, Regeneration, and Hydraulic Architecture of Larix sibirica in the Mongolian Forest-Steppe / Elmira Khansaritoreh ; Gutachter: Edmone Roffael, Christoph Leuschner ; Betreuer: Markus Hauck." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1159768870/34.

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Horstkotte, Tim. "Contested Landscapes : social-ecological interactions between forestry and reindeer husbandry." Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-66386.

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Throughout northern Fennoscandia, reindeer husbandry is a central part in the cultural heritage of the Sámi people. In its history, Sámi culture and reindeer husbandry have undergone significant adaptations to environmental, social and political challenges. Landscape changes on the winter grazing grounds were mainly driven by resource exploitation, especially by industrialized forestry. Important grazing resources were lost, i.e. terrestrial and arboreal lichens that constitute essential key elements in the herding year. In my thesis, I explore the consequences of these transformations in Swedish boreal forests for reindeer husbandry. The multi-disciplinary approach integrates interview studies, ecological fieldwork and theoretical modeling of forest development. I emphasize the understanding of landscapes as multi-dimensional concepts with ecological, social and economic components. They interact in determining the amount of landscape fragmentation in physical or administrative ways, or in enabling reindeer herders to move between different landscape elements. These elements, e.g. forest stands of different ages, can react differently to winter weather. Thus, they enable reindeer herders to adjust their grazing grounds according to the availability of forage, mediated by snow conditions. However, forestry practices have reduced the abundance of old-growth forests, and therewith the functionality of the landscape. By comparing snow conditions in different forest types, I show that multi-layered canopies can offer a more diverse pattern of snow hardness. However, the interaction between forest characteristics with snow is strongly dependent on weather conditions, e.g. the timing and intensity of warm spells. The prevalence of single-layered forest stands therefore can lead to a reduction in snow variability and potentially restricts the availability of suitable grazing grounds for reindeer. If snow conditions hinder reindeer in foraging on terrestrial lichens, old forests formerly supplied reindeer with arboreal lichens. I show how industrial forestry has reduced the availability of this emergency forage by the reduction of old forests and increased landscape fragmentation and analyze the consequences of different management strategies on future habitat availability for arboreal lichens. By integrating these results into a model of forest management, I offer insights into consequences arising from different priorities that either favor timber production or the development of lichen-rich grazing grounds. In conclusion, I emphasize the importance of landscape diversity, as well as the ability to make use of this diversity, as a source of adaptability of reindeer husbandry to changes in grazing conditions by e.g. winter weather dynamics. A shared future of reindeer husbandry and forestry could be fostered by encouraging the social-ecological co-evolution of multiple use landscapes and the enhancement of the cultural and biological significance of the Swedish boreal forests.

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Veljanoska, Stefanija. "Agricultural risk, remittances and climate change in rural Africa." Thesis, Paris 1, 2016. http://www.theses.fr/2016PA01E057/document.

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Dans le cadre de cette thèse, nous nous intéressons à l'étude des décisions des ménages ruraux Ougandais en termes de gestion des risques climatiques. Dans un premier temps, nous testons l'impact des transferts des fonds des migrants sur le niveau de spécialisation des cultures agricoles ainsi que le niveau de risque du portefeuille des cultures des ménages contraints par l'accès aux marchés du crédit et de l'assurance. Nous complétons cette première analyse avec une étude sur la capacité des transferts des migrants à encourager les ménages à utiliser des inputs plus risqués tels que les engrais. Dans un troisième temps, nous explorons si le morcellement des terres peut réduire les effets négatifs de la variabilité des précipitations sur les rendements des cultures agricoles. Le dernier objectif de cette thèse est d'analyser l'impact de l'inégalité d'accès à l'eau sur l'intensité et l'incidence des manifestations et des émeutes au sein d'un pays. Le point central et commun aux différents chapitres est la variabilité climatique : quelles sont les conséquences pour les ménages agricoles ; comment les ménages peuvent se protéger contre les aléas climatiques et quelles sont les implications pour la disponibilité de l'eau et les conflits. Telles sont les questions que la thèse vise à aborder à travers une approche micro-économétrique
The dissertation provides evidence on the agricultural decisions of rural Ugandan households in terms of risk management against weather variability. First, I study the impact of remittances sent by migrants on households' degree of crop specialization and crop riskiness, as remittances may, to some extent, relieve credit and risk constraints. I complete the first objective with a second analysis that explores if remittances can motivate households to use riskier inputs - fertilizers. Third, I examine whether land fragmentation can reduce the negative impacts of rainfall variability on farmers' crop yields. In the final chapter, I test whether inequality in access to water for consumption may increase the incidence and the intensity of low-level conflicts. The central and common theme of the different chapters is weather variability: what are the consequences for agricultural households, how can households protect themselves against weather fluctuations and what are the implications for water availability and social conflict. Those are the questions that the dissertation aims at addressing with a micro-level empirical approach

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Dissertations / Theses on the topic 'Land fragmentation'

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