Dissertations / Theses: 'Dry tree'

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Sykes, Rebecca J. "Tree species coexistence in a Mexican seasonally dry tropical forest." Thesis, University of Southampton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439370.

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Nascimento, Diego Raymundo. "Artificial reservoirs affect tree functional components of tropical dry forests." Universidade Federal de Juiz de Fora (UFJF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/5817.

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A construção de barragens é uma das principais formas em que o ser humano altera os ecossistemas. Entender como reservatórios advindos da barragem afetam florestas tropicais secas é essencial, uma vez que essas florestas estão localizadas em áreas de alto impacto de barragens no mundo. Nosso objetivo foi avaliar até que ponto reservatórios podem afetar mudanças na estrutura, diversidade taxonômica e componentes da diversidade funcional de florestas secas após 10 anos da construção de uma barragem. Em fragmentos de florestas tropicais secas nós apresentamos dados de dinâmica temporal de 120 parcelas permanentes que estavam longe (>700 m) do curso de água antes do represamento, e agora estão na borda (0 to 60 m) do reservatório. Parcelas mais próximas ao reservatório apresentaram um maior aumento na diversidade funcional, mas não apresentaram relações significativas na diversidade taxonômica. Parcelas próximas ao reservatório também apresentaram uma maior diminuição em densidade de madeira (relacionado com alta disponibilidade de água) e uma maior diminuição em área foliar específica e maior aumento de indivíduos com folhas compostas (possivelmente relacionado à maior disponibilidade de luz, criada pela borda do reservatório). Nossos resultados sugerem que reservatórios podem alterar a funcionalidade de florestas tropicais secas ao longo do tempo e evidencia a importância de mais estudos que relacionem essas mudanças com processos demográficos.
Reservoir construction is one of the main ways humans alter ecosystems by damming rivers. Understanding how reservoir dams affect forests is essential once they are usually in the highest impact areas of the world. We aimed to evaluate to what extent an artificial reservoir affected changes in the structure, species diversity and components of functional diversity of a tropical dry forest after 10 years of the dam construction. In the patches of the tropical dry forest we present dynamic data of 120 permanent plots that were far (> 700 m) from the watercourse before damming and are now on the edge of it (0 to 60 m). We evaluated how changes in community structure, taxonomy diversity and functional components were related with distance of the reservoir shorelines. Plots closer to the reservoir showed higher increase in functional diversity but do not showed significant relationships with taxonomy diversity. Plots closer to the reservoir also showed higher decrease in wood density (related to high water availability), higher decrease in specific leaf area, and increase in compoundness (possible due to increase in light incidence due to reservoir edge). Our results suggest that reservoirs can alter functionality of tropical dry forests over time and highlight the importance of more studies relating these changes with demographic process.

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González-Rivas, Benigno. "Tree species diversity and regeneration of tropical dry forests in Nicaragua /." Umeå : Dept. of Silviculture, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200558.pdf.

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Ziegler, Susy Svatek, Evan R. Larson, Julia Rauchfuss, and Grant P. Elliott. "Tree Establishment During Dry Spells At An Oak Savanna In Minnesota." Tree-Ring Society, 2008. http://hdl.handle.net/10150/622571.

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Recent research has challenged the long-standing hypothesis that forests in the Upper Midwest of the United States developed during wetter periods and retreated during dry periods. We explored this debate by examining patterns of tree establishment on an oak savanna in east-central Minnesota within the context of variable moisture availability and fire suppression. We used superposed epoch analyses (SEA) to evaluate the mean moisture conditions for a 21-year window surrounding tree establishment dates. Before effective fire suppression (1809–1939), 24 of 42 trees with pith dates (62%) grew to 30-cm height during dry years (Palmer Drought Severity Index < -1), versus only 5 of 42 (12%) that established in wet years (PDSI > 1). Significantly more trees established during dry periods (negative PDSI values) than would be expected with the proportion of wet-to-dry years (x²= 10.738, df = 1, p-value = 0.001). Twenty of the complete sample of 74 trees with pith dates (27%) established during drought in the 1930s. We hypothesize that dry conditions limited plant productivity, which in turn decreased competition between grasses and tree seedlings and reduced rates of accumulation of fine fuels, enabling seedlings to grow tall enough to resist subsequent fires. We recommend SEA as a methodological approach to compare historical climate conditions with the timing of regeneration success in other regions of forest expansion.

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Nakai, Wataru. "Examination of stable oxygen isotope as a tree ring proxy of tropical ring-less trees." Kyoto University, 2019. http://hdl.handle.net/2433/242922.

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Kayofa, Fillemon. "Natural regeneration potential of Pterocarpus angolensis (Kiaat Tree) in the dry forests of northern Namibia." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97146.

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Thesis (MSc)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Pterocarpus angolensis is one of the timber tree species that regenerates naturally in the dry forest of Namibia, mainly assisted by the influence of forest fires. Tree development goes through a prolonged suffrutex stage to reach the sapling stage and then, finally, the bole tree stage. This study focused on assessing the main factors facilitating the development of Pterocarpus angolensis seedlings through the suffrutex stage to the sapling stage in Namibia dry forests. To achieve the study objectives three study locations (Okongo and Ncumcara Community Forests and Caprivi State Forest) were selected, representing a rainfall gradient. Within each study location, two different fire history treatments (recently burnt (RB) and recently unburnt (RU)) were selected, and four plots were randomly selected from each fire history treatment. Face to face individual interviews was conducted with community members surrounding the three forests to obtain indigenous knowledge information about Pterocarpus angolensis tree development. Seedlings and saplings found in all plots were counted and measured (tree height and diameter at breast height (DBH)) while trees more than 3 m high were only counted and measured for DBH. Laboratory analysis was performed to determine basic soil texture and nutrient status. In addition, destructive sampling was done on individual trees in the seedling and sapling stages at each study location. The destructive samples allowed for estimation of biomass in above and below ground components, determination of carbohydrate storage in the taproots and estimation of tree age by counting growth rings on the neck disc of the taproot sample. These measures could shed light on the tree development through the suffrutex stage. The main agents causing Pterocarpus angolensis tree damage and stand disturbances observed are drought, fires, insects, diseases, temperature, lightning, wind, animals and humans. Forest fires were found to be one of the major disturbances in all the study locations, particularly damaging to seedlings when fire intensity is high. Likewise, the most important factors influencing the tree development from seedlings to sapling and sapling to bole tree stages are soil water, soil fertility, plant competition, sunlight and fires. Through counting growth rings of taproot neck discs, it is estimated that the ages of seedlings most commonly range from 5 to 12 years in the dry forests of Okongo, Ncumcara and Caprivi. The soil texture in the three forests is dominated by sand, with the soil reaction usually being moderately acidic while the soils have low levels of organic carbon, phosphorus and exchangeable base cations. This study revealed that Caprivi State Forest (location with the highest rainfall) has the highest stand density followed by Okongo Community Forest and Ncumcara Community Forest with the lowest. Trees were grouped into different DBH and height classes. The highest numbers of trees are found in DBH class 0 – 10 cm and in height class 0.6 – 1.0 m at Okongo Community Forest but at Ncumcara and Caprivi many of the trees are in height class 1.1 – 1.5 m. The mean DBH difference is significant between locations but not significant between fire history treatments. A higher abundance of mature trees are found at Okongo Community Forest while a greater abundance of saplings occur at Ncumcara Community Forest which shows a significant difference between study locations. Seedling abundance is the same across study locations and fire history treatments. The difference in stand structure between study locations appears to be strongly influenced by different management regimes on the three locations. A majority of respondents from all the study locations alleged soil water followed by soil fertility as the main influential factors to Pterocarpus angolensis development. Again, most of the respondents revealed that seedling takes 4 – 7 years to reach sapling stage and their main environmental disturbance is fire. Tree cutting by members of the community was also perceived by the respondents as an important non-environmental disturbance. The most abundant tree development stage perceived by respondents was mature trees while seedlings rated the sparsest stage. Based on the respondents no silvicultural practices are performed to promote Pterocarpus angolensis growth. It follows that the Kiaat trees are currently growing without human intervention that might enhance their development. A combination of social survey (interview) and ecological survey provided reliable information on ecological processes. A weak positive significant correlation relationship existed between shoot mass (aboveground biomass) and taproot mass (belowground biomass), meaning when the taproot mass increases the shoot mass also increases. Analysis of non-structural carbohydrates (NSC) storage in taproots showed that both sugar and starch contents in the taproots could facilitate the survival of the tree during suffrutex stages and its rapid growth thereafter. Based on this study Pterocarpus angolensis regeneration in these three dry forests is poor because seedling abundance is the lowest compared to saplings and mature trees. These study findings can be used as the basis for further studies to predict Pterocarpus angolensis natural regeneration in the dry forests, as well as input when management regimes are being developed for the dry forests of North Namibia.
AFRIKAANSE OPSOMMING: Pterocarpus angolensis (Kiaat) is een van die boomspesies wat natuurlik verjong in die droë bosveld van Namibië, met die hulp van bosbrande. Die boom ontwikkel deur ŉ lang semi-struik stadium waartydens die boompies as saailinge bekendstaan. Daarna ontwikkel dit deur die jongboom stadium tot dit uiteindelik die kroon stadium bereik. Hierdie studie fokus op die faktore bydra tot die ontwikkeling van Pterocarpus angolensis van die semi-struik stadium na die jongboom stadium in die droë bosveld van Namibië. Om die doelstellings van die tesis te bereik is drie studiegebiede gekies langs ŉ reënvalgradiënt (naamlik Okongo en Ncumcara gemeenskapsbosse asook Caprivi Staatsbos). Binne elke studiegebied is twee behandelings met verskillende brandgeskiedenis gekies (gebrand of nie-gebrand in die onlangse verlede). Vier persele is ewekansig uit elk van hierdie behandelings gekies vir eksperimentering. Persoonlike onderhoude is gevoer met gemeenskapslede wat in die omgewing woon ten einde inheemse kennis en inligting te versamel oor die ontwikkeling van die jong Pterocarpus angolensis bome. Alle saailinge en jongbome wat voorkom in die persele is getel en gemeet (boomhoogte en deursnee op borshoogte (DBH)) terwyl bome wat hoër as 3 m is, slegs getel en vir DBH gemeet is. Laboratoriumtoetse is gedoen op grondmonsters ten einde ‘n basiese beskrywing van die grondtekstuur en voedingstofstatus te verkry. Verder is destruktiewe bemonstering toegepas op bome in beide die saailing en jongboom stadium op elke studiegebied. Hierdie bemonstering het dit moontlik gemaak om bogrondse en ondergrondse biomassa te skat, om die opberging van koolhidrate in die penwortels te bepaal, en ook om die boom ouderdom te skat vanaf jaarringe in die nek van die penwortel monster. Hierdie metings kon lig werp op die boomontwikkeling deur die semi-struik stadium. Die faktore wat skade aan Pterocarpus angolensis bome veroorsaak asook versteuring van die opstande waarin die bome voorkom is droogte, brande, insekte, siektes, temperatuur uiterstes, weerlig, wind, diere en mense. Die bevindinge dui op bosbrande as een van die belangrikste versteuringsfaktor in al drie studiegebiede; dit is veral skadelik vir saailinge in die semi-struik stadium wanneer die vuurintensiteit hoog is. Die faktore wat die boomontwikkeling van saailing, na jongboom en kroonstadium beïnvloed is hoofsaaklik grondwater, grondvrugbaarheid, plantkompetisie, sonlig en brande. Die ouderdom van saailinge (bepaal vanaf jaarring tellings in die nek van penwortel monsters) van die meeste saailinge én jongbome is na raming tussen 5 en 12 jaar vir die droë bosse in die studiegebiede van Okongo, Ncumcara en Caprivi. Die grondtekstuur van hierdie studie se drie bosgebiede is hoofsaaklik sanderig, met ’n effens suur grondreaksie terwyl die gronde lae vlakke van organiese koolstof, fosfor, en uitruilbare basiese katione bevat. Die studie het aangedui dat Caprivi staatsbos (met die hoogste reënval) die digste opstande huisves, gevolg deur Okongo en dan Ncumcara gemeenskapsbos, met die laagste digtheid. Bome is gegroepeer in verskillende DBH en hoogte klasse. Die meeste bome kom voor in die DBH klas van 0-10 cm en in die hoogteklas van 0.6 – 1.0 m by Okongo, maar by Ncumcara en Caprivi is daar meer bome in die hoogteklas van 1.1 - 1.5 m. Die gemiddelde DBH verskil is betekenisvol tussen studiegebiede, maar is nie betekenisvol verskillend tussen brandgeskiedenis behandelings nie. ’n Hoër voorkoms van volwasse bome is by Okongo aangetref, terwyl ’n hoër voorkoms van jongbome by Ncumcara waargeneem is, en hierdie verskil was statisties betekenisvol. Die voorkoms van saailinge is soortgelyk oor alle studiegebiede en brandgeskiedenis behandelings heen. Die verskil in die struktuur van die opstande op die drie studiegebiede word skynbaar sterk beïnvloed deur verskillende bestuurspraktyke wat in elke gebied toegepas word. Die meerderheid van respondente van al drie studiegebiede beweer dat grondwater, gevolg deur grondvrugbaarheid die belangrikste faktore is wat P. angolensis ontwikkeling beïnvloed. Meeste van die respondente onthul dat saailinge 4 tot 7 jaar neem om die jongboom stadium te bereik en dat die belangrikste versteuringsagent bosbrande is. ŉ Belangrike nie-omgewingsfaktor wat verantwoordelik is vir versteuring in die bosse is mense wat bome, lote en/of takke afsaag. Respondente is van mening dat volwasse bome die grootteklas met die mees algemene voorkoms is, terwyl saailinge die skaarsste grootteklas uitmaak. Die respondente het aangedui dat geen boskultuurpraktyke toegepas word om die groei van P. angolensis aan te help nie. Die gevolgtrekking is dus dat die Kiaatbome tans groei sonder menslike ingryping om hul ontwikkeling te verbeter. Die kombinasie van persoonlike onderhoude en ŉ ekologiese opnames het betroubare inligting rakende ekologiese prosesse opgelewer. ’n Swak positiewe, maar betekenisvolle korrelasie bestaan tussen die massa van die bogrondse lote en die penwortelmassa, wat beteken dat die lote se massa toeneem met toenemende wortelmassa. Analise van opgebergde nie-strukturele koolhidraatreserwes in die penwortel toon dat beide suiker- én styselinhoud in die penwortels die oorlewing van die boom in die struikstadium aanhelp, asook sy vinnige groei na die struikstadium. Die feit dat die saailinge minder volop is as jongbome en volwasse bome in hierdie studie dui aan dat verjonging van Pterocarpus angolensis in hierdie droë bosse maar swak is. Die bevindinge van die studie bevat inligting wat gebruik kans word (a) as die grondslag van verdere studies op die natuurlike verjonging van Pterocarpus angolensis in droë bosse, en (b) as inset wanneer bestuursaanbevelings vir die droë bosse van Noord Namibië ontwikkel word.

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Garrison, Jennifer SE. "The role of alien tree plantations and Avian seed-dispersers in native dry forest restoration in Hawaii." Thesis, University of Hawaii at Manoa, 2003. http://hdl.handle.net/10125/6858.

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Foresters often plant tree plantations to speed rehabilitation of degraded forestlands. I compared mature plantations of four alien species (Casuarina spp, Eucalyptus robusta, Fraxinus uhdei, and Grevillea robusta) to remnant patches of native dry forest in the Honouliuli Forest Preserve on Oʻahu, Hawaiʻi to determine if plantations aid the recovery of native plants in disturbed dry habitats. I measured soil pH and nutrients, forest floor structure, vegetation structure, plant species richness and abundance, seed rain species richness and abundance, native seed germination success and seedling survival, fruit availability, alien and native bird species richness and abundance, and avian seed-dispersal. Alien tree plantations do not appear to promote native plant restoration in dry areas in Honouliuli. There were several limitations to native plant establishment in tree plantations including low native seed dispersal (by both birds and wind), low seed germination rates, and low seedling survival in plantations. The understory communities of the five forest types indicate that their futures differ greatly (Ch 3). Casuarina and Fraxinus understories had dense self-regeneration and low proportions of native or invasive species. These forest types will likely remain stable over time. In contrast, Eucalyptus and Grevillea plantation trees are not replacing themselves. Native tree saplings were rare in Eucalyptus and Grevillea plantations, and these forest types seem destined to be replaced by invasive trees as the planted trees senesee. Grevillea plantations comprise a large proportion of the planted trees in Honouliuli, particularly in the southern end of the Preserve. These stands will beconverted to open invasive woodlands. Remnant patches of native lowland dry forest in Honouliuli face an uncertain future. While around 30% of the understory tree seedlings and saplings were native, the remaining belonged to invasive species (Ch 2). Psidium cattleianum, in particular, is overtaking the native forests. As the Psidium stands expand they will further reduce the size of native forest patches. Future management efforts for lowland forests in Honouliuli should focus on control of invasive species in the remnant patches of native forest, and on dry forest restoration in the Grevillea plantations in the south end of the Preserve.
xii, 370 leaves

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Paré, Souleymane. "Land use dynamics, tree diversity and local perception of dry forest decline in southern Burkina Faso, West Africa /." Umeå : Dept. of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/200878.pdf.

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Werneck, Fernanda. "Diversification and Conservation in the South American Dry Biomes: Distribution Modeling and Multilocus Lizard Phylogeography." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3308.

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The understanding of diversification of intraspecific lineages can shed light on speciation processes and ultimately biogeographic patterns across multiple spatial and temporal scales. In this dissertation I investigated the geographical and ecological factors promoting diversification across the South American dry diagonal biomes (i.e. Cerrado, Chaco, and Seasonally Dry Tropical Forests - SDTFs), through a coupled approach between multilocus phylogeographic and geospatial methods, in the larger context of interpreting the consequences of the resulting patterns for the conservation of biodiversity and evolutionary processes. In Chapter 1 I evaluate biogeographic hypotheses previously proposed and emphasize that the dry diagonal biomes are particularly biodiverse and biogeographically complex, but poorly studied and under protected. I also propose testable predictions for the subsequent chapters and future diversification studies. In the subsequent chapters I adopt a biodiversity prediction approach based on estimating palaeodistributions and habitat stability surfaces to formulate and test spatially explicit diversification hypotheses based on squamate richness and phylogeography. In Chapter 2 I identify historically stable areas of SDTFs and in Chapter 3 I found that the historical climatic stability is a good predictor of Cerrado squamate richness. In Chapter 4 I use a multilocus dataset to estimate the phylogenetic relationships among described species of the lizard genus Phyllopezus (Phyllodactylidae), distributed across the ‘dry diagonal’ biomes. In Chapter 5 I used a dense sampling design focused in the species complex P. pollicaris (more individuals, localities, and markers), and coalescent phylogeographic methods to test the relative influences of Tertiary geomorphological vs. Quaternary climatic events on diversification in this lizard. I found unprecedented levels of cryptic genetic diversity, deep phylogeographic structure, and diversification dating back to at least the Neogene with persistence across Quaternary fluctuations. My dissertation emphasizes that patterns of diversification across the ‘dry diagonal’ biomes are much more complex than previously proposed and reflect the primary influence of geologically old processes. Evidence of allopatric and ecological speciation between lineages that coincide with genetic clusters associated with each of the biomes, contradicts early views that the biomes would have a shared diversification history. These patterns illustrate that low-vagility complexes, characterized by strong structure and pre-Pleistocene divergences, represent ideal radiations to investigate broad biogeography of associated biomes. Future studies should investigate patterns of temporal and spatial congruence across co-distributed taxa, and integrate morphological and further ecological data to refine species limits, taxonomy, and patterns of trait evolution across these radiations.

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Gibson, Jacob R. "Individualistic Response of Piñon and Juniper Tree Species Distributions to Climate Change in North America's Arid Interior West." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/908.

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Piñon and juniper tree species have species-specific climatic requirements, resulting in unique distributions and differential responses to climate change. Piñons and junipers co-dominate the arid woodlands of North America as groups with widespread hybridization. Two piñons, Pinus edulis; P. monophylla, and four junipers, Juniperus deppeana var. deppeana; J. monosperma; J. occidentalis; J. osteosperma, are endemic to the midlatitude interior west and form three groups of hybridizing sister species, P. edulis-P. monophylla; J. deppeana var. deppeana-J. monosperma; J. occidentalis-J. osteosperma. Recent droughts have caused widespread mortality among piñons, but have had less impact on junipers and indicate shifts in co-occurrence have already begun in response to global climate change. Within these groups hybridization likely plays an important role in such distribution changes. The central objective of this thesis is to forecast the distributions of piñons and junipers endemic to the US under modeled climate change for the 21st century. Species distribution models are built with an emphasis placed on aligning the life cycle dynamics of the species within the temporal and spatial resolution of predictor variables, and within the modeling technique. Two concerns surrounding species distribution modeling are addressed. First, concerns regarding the extent to which species are at equilibrium with the current climate are addressed by incorporating dispersal into the model building process. Second, concerns regarding the potential role of hybridization between closely related species are addressed by building distribution models for each of the three sister species groups as well as the six component species. Species distribution models exhibited individualistic responses to modeled climate change. Modeled areal loss was greater than gain for all species, which is reflected in changes of co-occurrence. Piñon-juniper richness is forecast to increase in the northern Colorado Plateau, eastern Great Basin, and Rocky Mountains. The sister-species models forecast greater areal gain, and less areal loss, along hybridization zones for P. edulis-P. monophylla and for J. occidentalis-J. osteosperma, but forecast greater areal loss along the periphery of the component species distributions. The sister-species model for J. deppeana var. deppeana-J. monosperma forecasts overall greater areal loss than the component species. In general, forecast changes in latitude and elevation are about one third of the changes inferred, from the fossil record, to have occurred following the transition to the current interglacial ~10,000 years ago.

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Cavalcante, Carolline Barros. "Arquitetura de copas de espécies da caatinga: Um reflexo do estresse hídrico na vegetação do semiárido brasileiro." Universidade Estadual da Paraíba, 2014. http://tede.bc.uepb.edu.br/jspui/handle/tede/3053.

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The crown architecture is influenced by genetic and environmental factors, which are intermediated by plant hormones. In order to avoid radiation excess and water loss through transpiration, the species from arid lands such as Caatinga developed survival strategies. In Caatinga lands, the species were grouped according to their leaf phenology and it’s expected that the different phenologic patterns be related to the morphologic characteristics of the plant, including its crown. In this case, this study aimed to characterize the crown architecture of groups having different leaf phenologies from Caatinga and understand the existing relations. Nine crown species were represented, being three evergreen, three 2- to 3-month deciduous and three 4- to 6-month, and for each species three individuals were analyzed, totaling up 27. For each individual, it was accounted the number of connectors, regular, final and emission nodes, besides the distances between the different kinds of nodes. The results showed that among the analyzed groups, the greatest averages to the number of nodes and connectors were found in the 2- to 3-month-old deciduous group, followed by the evergreen group, and finally the 4- to 6-month-old deciduous group. What concerns the distances, only the distance between the final adjoining nodes differed among the groups, in a way that the evergreen trees showed the lowest average. The less segmented deciduous canopies of 4-6 months facilitate the quick distribution of resources throughout the plant, while canopies more segmented, as 2-3 months avoid self-shading of leaves along the branches. Evergreen species showed complexity of canopy reduced with self-shading avoiding excessive water loss, indicating a relationship between leaf phenology and canopy architecture in species of the Caatinga.
A arquitetura copa é influenciada por fatores genéticos e ambientais, que são intermediados por hormônios vegetais. Para evitar o excesso de radiação e a perda de água por transpiração, as espécies de ambientes áridos como a Caatinga desenvolveram estratégias de sobrevivência. Na Caatinga, as espécies foram agrupadas de acordo com a sua fenologia foliar e espera-se que os diferentes padrões fenológicos estejam relacionados às características morfológicas da planta, inclusive de sua copa. Sendo assim, objetivo deste estudo foi caracterizar a arquitetura da copa de grupos com diferentes fenologias foliares da Caatinga e compreender as relações existentes. Foram representadas as copas nove espécies, sendo três perenifólias, três decíduas de 2-3 meses e três decíduas de 4-6 meses e para cada espécie foram analisados três indivíduos, totalizando 27. Para cada indivíduo foi contabilizado o número de conectores, nós regulares, nós finais e nós de emissão, além das distâncias entre os diferentes tipos de nós. Os resultados mostraram que entre os grupos analisados, as maiores médias para o número de nós e conectores foram apresentadas pelo grupo das decíduas de 2-3 meses, seguido pelo grupo das perenifólias e por fim, pelo grupo das decíduas de 4-6 meses. Para as distâncias, apenas a distância entre nós finais vizinhos diferiu entre os grupos, de modo que o grupo das perenifólias apresentou a menor média. As copas menos segmentadas das decíduas de 4-6 meses facilitam a distribuição de recursos por toda a planta de forma rápida, enquanto que copas mais segmentadas, como das decíduas de 2-3 meses evitam o autosombreamento das folhas ao longo dos ramos. Espécies perenifólias apresentaram complexidade de copa reduzida, com autosombreamtento evitando a perda excessiva de água, evidenciando uma relação entre a fenologia foliar e a arquitetura da copa em espécies da Caatinga.

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Butz, Jan Philipp Verfasser], Sophie [Akademischer Betreuer] Graefe, Dirk [Gutachter] [Hölscher, Bernhard [Gutachter] Schuldt, and Holger [Gutachter] Kreft. "Tree Water Use Strategies in a Neotropical Dry Forest / Jan Philipp Butz ; Gutachter: Dirk, Hölscher; Bernhard, Schuldt; Holger, Kreft ; Betreuer: Sophie, Graefe." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/119730388X/34.

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Butz, Jan Philipp Verfasser], Sophie [Akademischer Betreuer] [Graefe, Dirk [Gutachter] Hölscher, Bernhard [Gutachter] Schuldt, and Holger [Gutachter] Kreft. "Tree Water Use Strategies in a Neotropical Dry Forest / Jan Philipp Butz ; Gutachter: Dirk, Hölscher; Bernhard, Schuldt; Holger, Kreft ; Betreuer: Sophie, Graefe." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://nbn-resolving.de/urn:nbn:de:gbv:7-21.11130/00-1735-0000-0005-126F-B-8.

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Vinya, Royd. "Stem hydraulic architecture and xylem vulnerability to cavitation for miombo woodlands canopy tree species." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:9028b995-5379-4969-8a7b-59a7aa7ab533.

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Africa's miombo woodlands constitute one of the most important dry tropical forests on earth, yet the hydraulic function of these woodlands remains poorly researched. Given the current predictions of increased aridity by the end of this century in the miombo ecoregion, understanding the likely response of miombo woodlands tree species to water stress is crucial in planning adaptation strategies. Predicting the response of miombo woodlands to future climate trends is hampered by a lack of knowledge on the physiology of the common miombo woodlands tree species. In particular, plant-water relations for this woodlands type are not well understood. An understanding of plant-water relations for this woodlands type will provide insights into how water limits tree species distribution in this ecosystem. This will also improve our prediction model on the likely response of this ecosystem to predicted climate change. For this reason, the overall objective of this research was to evaluate the hydraulic architecture and xylem vulnerability to cavitation for nine principal miombo woodlands tree species differing in drought tolerance ability and habitat preference. This was achieved by; examining the hydraulic properties and evaluating the extent to which each hydraulic design was vulnerable to water stress-induced xylem cavitation; investigating how seasonal changes in plant-water relations influences seasonal patterns of leaf display and; analyzing the relationship between stem hydraulic supply and leaf functional traits related to drought tolerance ability. This research has found that drought-intolerant tree species with mesic specialization have more efficient stem hydraulic systems than co-occurring habitat broad ranging species. Broad ranging tree species attain wider habitat distribution by adjusting their hydraulic supply in response to changing ecosystem water availability. The finding that hydraulic properties differ significantly between tree species with contrasting habitat preference suggests that tree hydraulic design may have some adaptive ecological role in influencing species habitat preferences in miombo woodlands. The evaluation of xylem vulnerability to cavitation revealed that mesic specialized tree species were more vulnerable to water stress-induced cavitation than habitat broad ranging tree species. Vulnerability to cavitation in individuals from the same broad-ranging species growing in contrasting habitats showed only marginal and statistically insignificant (P > 0.05) differences between wet and dry sites. In the investigation of the influence of seasonal changes in stem water relations on seasonal leaf display, seasonal rhythms in stem water status were found to exert significant controls on leaf phenology. Mesic specialists had strong stem water controls throughout the year in comparison to broad ranging tree species. An analysis of the relationship between stem hydraulic supply and leaf functional traits suggests that stem hydraulic supply constrains leaf biomass allocation patterns among miombo tree species. Mesic specialists tend to invest more in leaf longevity than broad ranging tree species. This thesis has uncovered some interesting relationships between plant-water-relations and the distribution of miombo woodlands tree species. These results lead to the conclusion that in an event of increased ecosystem drying under future climate trends, tree species with mesic specialisation are at a greater risk of experiencing cavitation related species mortality than broad ranging ones.

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LoÌpez, Juan Carlos Flores. "Exploring the potential of sound management of forest and tree resources on cattle farms located in tropical dry forest of Guanacaste, Costa Rica." Thesis, Bangor University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432792.

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Vargas, Juan Jose Quiros. "Multispectral aerial images to phenotype yield potential and tree inventory mapping: case studies in dry pea (Pisum sativum) and apple (Malus domestica) nursery." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11152/tde-28022018-180550/.

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Field data collection involves time and money consuming processes, additionally carrying possible measurement errors. With the technological advance in the last years, low cost remote sensing tools have emerged to facilitate procedures for in-field measurements, being one of the most known techniques the use of multispectral cameras coupled to RPA. These tools are complemented by the implementation of procedures in GIS and image-processing software, from which are developed methodologies leading to extract target values from a certain original set of data. In this work, multispectral images were used in two case studies: (1) for yield estimation in pea plots for breeding research, and (2) for plant counting in an apple nursery planted directly on the soil; both fields are located in Washington State, USA. In the first case, a reliable and replicable methodology for yield estimation was created as a high throughput phenotyping technique; while in the second case an algorithm capable of identifying the number of apple plants with more than 95% accuracy was developed. In both studies, remote sensing is used as an efficient and practical way to improve field operations under the specified conditions of each case.
A coleta de dados de campo envolve processos de grande consumo em tempo e dinheiro, ademais de levar o risco de possíveis erros de medição. Com o avanço tecnológico nos últimos anos, surgiram ferramentas de sensoriamento remoto de baixo custo para facilitar procedimentos de medição em campo, sendo uma das técnicas mais conhecidas o uso de câmeras multiespectrales acopladas a um ARP. Essas ferramentas são complementadas pela implementação de procedimentos em programas SIG e de processamento de imagens, a partir dos quais são desenvolvidas metodologias que visam extrair valores alvo desde um determinado conjunto original de dados. Neste trabalho, foram utilizadas imagens multiespectrais no desenvolvimento de dois estudos de caso: (1) para estimativa de produtividade em parcelas para pesquisa de ervilha, e (2) para contagem de plantas em um viveiro de maçã plantado diretamente no solo; ambos os campos localizados no estado de Washington, EUA. No primeiro caso, foi criada uma metodologia confiável e replicável para estimativa de produtividade como técnica de fenotipagem de alto rendimento; enquanto no segundo caso, foi desenvolvido um algoritmo capaz de identificar o número de plantas de maçã com mais de 95% de exatidão. Em ambos os estudos, o sensoriamento remoto é usado como uma ferramenta eficiente e prática na melhora de operações de campo.

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McElhinny, Chris, and chris mcelhinny@anu edu au. "Quantifying stand structural complexity in woodland and dry Sclerophyll Forest, South-Eastern Australia." The Australian National University. Centre for Resource and Environmental Studies, 2005. http://thesis.anu.edu.au./public/adt-ANU20060322.133914.

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In this thesis I present and test a methodology for developing a stand scale index of structural complexity. If properly designed such an index can act as a summary variable for a larger set of stand structural attributes, providing a means of ranking stands in terms of their structural complexity, and by association, their biodiversity and vegetation condition. This type of index can also facilitate the use of alternative policy instruments for biodiversity conservation, such as mitigation banking, auctions and offsets, that rely on a common currency the index value that can be compared or traded between sites. My intention was to establish a clear and documentable methodology for developing a stand scale index of structural complexity, and to test this methodology using data from real stands.¶ As a starting point, I reviewed the literature concerning forest and woodland structure and found there was no clear definition of stand structural complexity, or definitive suite of structural attributes for characterising it. To address this issue, I defined stand structural complexity as a combined measure of the number of different structural attributes present in a stand, and the relative abundance of each of these attributes. This was analogous to approaches that have quantified diversity in terms of the abundance and richness of elements. It was also concluded from the review, that stand structural complexity should be viewed as a relative, rather than absolute concept, because the potential levels of different structural attributes are bound within certain limits determined by the inherent characteristics of the site in question, and the biota of the particular community will have evolved to reflect this range of variation. This implied that vegetation communities with naturally simple structures should have the potential to achieve high scores on an index of structural complexity.¶ I proposed the following five-stage methodology for developing an index of stand structural complexity: 1. Establish a comprehensive suite of stand structural attributes as a starting point for developing the index, by reviewing studies in which there is an established relationship between elements of biodiversity and structural attributes. 2. Develop a measurement system for quantifying the different attributes included in the comprehensive suite. 3. Use this measurement system to collect data from a representative set of stands across the range of vegetation condition (highly modified to unmodified) and developmental stages (regrowth to oldgrowth) occurring in the vegetation communities in which the index is intended to operate. 4. Identify a core set of structural attributes from an analysis of these data. 5. Combine the core attributes in a simple additive index, in which attributes are scored relative to their observed levels in each vegetation community.¶ Stage one of this methodology was addressed by reviewing a representative sample of the literature concerning fauna habitat relationships in temperate Australian forests and woodlands. This review identified fifty-five studies in south-east and south-west Australia, in which the presence or abundance of different fauna were significantly (p<0.05) associated with vegetation structural attributes. The majority of these studies concerned bird, arboreal mammal, and ground mammal habitat requirements, with relatively fewer studies addressing the habitat requirements of reptiles, invertebrates, bats or amphibians. Thirty four key structural attributes were identified from these fifty-five studies, by grouping similar attributes, and then representing each group with a single generic attribute. This set, in combination with structural attributes identified in the earlier review, provided the basis for developing an operational set of stand level attributes for the collection of data from study sites.¶ To address stages two and three of the methodology, data were collected from one woodland community Yellow Box-Red Gum (E. melliodora-E. Blakelyi ) and two dry sclerophyll forest communities Broadleaved Peppermint-Brittle Gum (E. dives-E. mannifera ), Scribbly Gum-Red Stringybark (E. rossii E. macrorhyncha ) in a 15,000 km2 study area in the South eastern Highlands Bioregion of Australia. A representative set of 48 sites was established within this study area, by identifying 24 strata, on the basis of the three vegetation communities, two catchments, two levels of rainfall and two levels of condition, and then locating two sites (replicates) within each stratum. At each site, three plots were systematically established, to provide an unbiased estimate of stand level means for 75 different structural attributes.¶ I applied a three-stage analysis to identify a core set of attributes from these data. The first stage a preliminary analysis indicated that the 48 study sites represented a broad range of condition, and that the two dry sclerophyll communities could be treated as a single community, which was structurally distinct from the woodland community. In the second stage of the analysis, thirteen core attributes were dentified using the criteria that a core attribute should:¶ 1. Be either, evenly or approximately normally distributed amongst study sites; 2. Distinguish between woodland and dry sclerophyll communities; 3. Function as a surrogate for other attributes; 4. Be efficient to measure in the field. The core attributes were: Vegetation cover <0.5m Vegetation cover 0.5-6.0m; Perennial species richness; Lifeform richness; Stand basal area of live trees; Quadratic mean diameter of live stems; ln(number of regenerating stems per ha+1); ln(number of hollow bearing trees per ha+1);ln(number of dead trees per ha+1);sqrt(number of live stems per ha >40cm dbh); sqrt(total log length per ha); sqrt(total largelog length per ha); Litter dry weight per ha. This analysis also demonstrated that the thirteen core attributes could be modelled as continuous variables, and that these variables were indicative of the scale at which the different attributes operated.¶ In the third and final stage of the analysis, Principal Components Analysis was used to test for redundancy amongst the core attributes. Although this analysis highlighted six groupings, within which attributes were correlated to some degree, these relationships were not considered sufficiently robust to justify reducing the number of core attributes.¶ The thirteen core attributes were combined in a simple additive index, in which, each attribute accounted for 10 points in a total index value of 130. Attributes were rescaled as a score from 0-10, using equations that modelled attribute score as a function of the raw attribute data. This maintained a high correlation (r > 0.97, p< 0.0001) between attribute scores and the original attribute data. Sensitivity analysis indicated that the index was not sensitive to attribute weightings, and on this basis attributes carried equal weight. In this form my index was straightforward to apply, and approximately normally distributed amongst study sites.¶ I demonstrated the practical application of the index in a user-friendly spreadsheet, designed to allow landowners and managers to assess the condition of their vegetation, and to identify management options. This spreadsheet calculated an index score from field data, and then used this score to rank the site relative to a set of reference sites. This added a regional context to the operation of the index, and is a potentially useful tool for identifying sites of high conservation value, or for identifying sites where management actions have maintained vegetation quality. The spreadsheet also incorporated the option of calculating an index score using a subset of attributes, and provided a measure of the uncertainty associated with this score.¶ I compared the proposed index with five prominent indices used to quantify vegetation condition or habitat value in temperate Australian ecosystems. These were: Newsome and Catlings (1979) Habitat Complexity Score, Watson et al.s (2001) Habitat Complexity Score, the Site Condition Score component of the Habitat Hectares Index of Parkes et al. (2003), the Vegetation Condition Score component of the Biodiversity Benefits Index of Oliver and Parkes (2003), and the Vegetation Condition Score component of the BioMetric Assessment Tool of Gibbons et al. (2004). I found that my index differentiated between study sites better than each of these indices. However, resource and time constraints precluded the use of a new and independent data set for this testing, so that the superior performance of my index must be interpreted cautiously.¶ As a group, the five indices I tested contained attributes describing compositional diversity, coarse woody debris, regeneration, large trees and hollow trees these were attributes that I also identified as core ones. However, unlike these indices, I quantified weeds indirectly through their effect on indigenous plant diversity, I included the contribution of non-indigenous species to vegetation cover and did not apply a discount to this contribution, I limited the direct assessment of regeneration to long-lived overstorey species, I used stand basal area as a surrogate for canopy cover, I quantified litter in terms of biomass (dry weight) rather than cover, and I included the additional attributes of quadratic mean diameter and the number of dead trees.¶ I also concluded that Parkes et al. (2003), Oliver and Parkes (2003), and Gibbons et al. (2004), misapplied the concept of benchmarking, by characterising attributes in terms of a benchmark range or average level. This ignored processes that underpin variation at the stand level, such as the increased development of some attributes at particular successional stages, and the fact that attributes can respond differently to disturbance agents. It also produced indices that were not particularly sensitive to the differences in attribute levels occurring between stands. I suggested that a more appropriate application of benchmarking would be at the overarching level of stand structural complexity, using a metric such as the index developed in this thesis. These benchmarks could reflect observed levels of structural complexity in unmodified natural stands at different successional stages, or thresholds for structural complexity at which a wide range of biota are present, and would define useful goals for guiding on-ground management.

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Sanidad, Wilfredo B. "Comparative studies of the water use characteristics of native tree species growing on a rehabilitated mine site in the wet - dry sub - tropics of Queensland /." St. Lucia, Qld, 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17423.pdf.

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Righi, Ciro Abbud. "Avaliação ecofisiológica do cafeeiro (Coffea arabica L.) em sistema agroflorestal e em monocultivo." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-05072005-153352/.

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O presente trabalho objetivou uma melhor compreensão do comportamento ecofisiológico do cafeeiro (Coffea arabica L.) sob diferentes condições de cultivo sejam, intensidade de sombra e demais interações com a seringueira (Hevea brasiliensis Müell. Arg.). Procurou-se evidenciar a competição por luz e água em função da distância das árvores e conseqüente diferente intensidade de competição. As hipóteses desse trabalho são: 1. A redução da disponibilidade de luz pelas árvores afeta o crescimento dos cafeeiros positivamente pela redução da transpiração e negativamente pela redução da fotossíntese líquida expressa como acúmulo de matéria seca da parte aérea; 2. Existe competição por luz entre o cafeeiro e a árvore sombreadora, sendo esta proporcional à distância entre as culturas e ao tamanho da árvore sombreadora; 3. O modelo matemático utilizado descreve adequadamente a disponibilidade de luz à cultura intercalar e pode ser uma importante ferramenta no desenho de sistemas agroflorestais (SAFs). O experimento foi instalado no campo experimental do Dept. de Produção Vegetal da Escola Superior de Agricultura Luiz de Queiroz - ESALQ/USP em Piracicaba-SP (22°4230 S, 47°3800 W - altitude 554 m) num delineamento em faixas (Strip-Plot), onde a distância do cafeeiro em relação às árvores define um tratamento, com níveis de interações entre as culturas a depender desta variável. De acordo com os dados experimentais obtidos pôde-se concluir que: 1. No intervalo entre 100 a 45% da irradiância disponível não houve redução no acúmulo de matéria seca dos cafeeiros. Maiores reduções da irradiância disponível levaram à diminuição do acúmulo de matéria seca diretamente proporcional, bem como modificações em suas características morfológicas e fisiológicas dada à adaptação a estas condições; 2. O sombreamento teve um efeito positivo na redução da transpiração por unidade de área foliar e por planta. Por outro lado teve um efeito negativo aumentando a transpiração por unidade de irradiância disponível; 3. O modelo matemático proposto por Goudriaan (1977) simulou bem a disponibilidade de irradiância à cultura intercalar, com boa aproximação entre os valores medidos e estimados. Assim, sua disponibilidade está relacionada com a distância e tamanho das árvores sombreadoras.
The main objective of the present work was the better understanding of the ecophysiological interactions within rubber trees (Hevea brasiliensis Müell. Arg.) and coffee plants (Coffea arabica L.). Above and below ground interactions were analyzed as a function of tree distance and consequent competition intensity. The main hypotheses of this research were: 1. Reduction on light availability due to trees affects the coffee plant growth positively by the transpiration reduction and negatively by the net photosynthesis reduction expressed by dry matter accumulation; 2. There are light competition between coffee plants and shade trees, been this proportional to the distance among crops and tree size; 3. The mathematical model used described adequately the light availability to the associated crop and can be an important tool on agroforestry system (AFS) design. The experiment was established in an experimental field belonging to the Dept. of Plant Production - ESALQ/USP at Piracicaba-Brazil (22°4230 S, 47°3800 W - altitude 554m) in random blocks with 11 treatments in a Strip-Plot design, where interactions intensity between crops were determined by the distances of the coffee plants to the tree. According to the experimental data obtained it was possible to concluded: 1. In the interval of 100 to 45% available irradiance coffee plants did not showed reduction on dry matter accumulation. Further reductions on available irradiance led to reduction on dry matter accumulation directly proportional, as well as to modifications on morphological and physiological characteristics due to its adaptation to these conditions; 2. Shade had a positive effect reducing transpiration per unit of leaf area and per plant. On the other hand had a negative effect rising the transpiration per unit of available irradiance; 3. The mathematical model proposed by Goudriaan (1977) presented a good simulation of the available irradiance to the associated crop, with good approximation between measured and simulated values. So, it availability is related to the distance and size of the shade trees.

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Chaparro, Mendivelso Hooz Angela. "Impacts of climate and drought on tree radial growth in Neotropical dry forests: Scaling up from short to long time-scales = Impactos del clima y las sequías en el crecimiento radial de los árboles en los bosques secos Neotropicales: Evaluación de sus efectos a diferentes escalas temporales." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/402722.

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This thesis analyzed the dynamics of tree radial growth at different time-scales in relation to climate and drought in two tropical dry forests (TDFs) from Colombia (Tuluá) and Bolivia (INPA). The specific objectives were: (i) To assess intra-annual patterns of radial growth (radial- increment dynamics and xylogenesis) in ten coexisting tree species from Tuluá and INPA and determine their relationship with climate and leaf phenology. (ii) To analyze the effects of climate and drought on long-term radial growth at different time-scales using dendrochronology in seven coexisting deciduous tree species from INPA. (iii) To evaluate the long-term radial growth responses to changes in climate water balance and determine their relationship with sapwood density in seven coexisting deciduous tree species from INPA. At intra-annual scales it was found that: (i) cambium reactivation and xylem growth of tree species occurred during the wet season, reflecting the influence of high precipitation and a positive water balance on the development of new xylem cells. (ii) In the semi-deciduous tree species from Tuluá the xylem growth period overlapped with the wet season, whereas, in the deciduous tree species from INPA, the growth period started at the mid wet season, when the tree crowns were fully developed. (iii) Temperature, as a determinant factor in the hourly fluctuations of both the vapor pressure deficit (VPD) and the evapotranspiration rate, could exert a huge influence on tree radial growth dynamics during the growing season. In Tuluá, the growing season was particularly associated with low temperatures and hence low VPD, while in INPA the growing season was related to high temperatures and VPD. Nevertheless, the high temperatures registered throughout the day at both TDFs negatively affected radial increment at hourly scales. Tree species could face the adverse dry conditions by restricting growth to periods of the day when temperatures are low. (iv) Stem shrinkage and swelling occurred at hourly to daily scales in all tree species, and most INPA tree species registered strong reversible shrinkage at monthly scales. Particularly, the climate controls on radial-increment dynamics varied between daily and monthly scales. At daily scales, there was a positive effect of high precipitation and positive water balance and a negative effect of VPD on the increment phase, while at monthly scales the precipitation was the main variable affecting radial increment positively. At inter-annual scales it was found that: (i) The tree radial growth showed a positive relationship with precipitation and climate water balance and a negative association with temperature, indicating that the tree species studied share high common growth variability in response to local climate. Nevertheless, the strongest response of growth to climate was species-specific, indicating that there was a differential sensitivity among tree species to these climate variables. (ii) The radial growth of all tree species responded positively to water balance during the wet season, but such responses differed among species as a function of their stem sapwood density. Specifically, sapwood density was negatively related to growth variability explained by water balance. Tree species with low-density wood and high production of sapwood were the most sensitive to water balance, whereas species with the opposite characteristics were the least sensitive ones. (iii) Tree species tolerated short-term droughts while they were particularly sensitive to long-lasting droughts. This indicates that tree species from the INPA site are predominantly sensitive in terms of growth reduction to long-lasting droughts. The most temperature-sensitive tree species, also showed the highest growth sensitivity to long-lasting droughts. In contrast, growth of the tree species with the lowest sensitivity to water balance, did not respond to long-term drought variability.
Esta tesis evaluó la dinámica del crecimiento radial a diferentes escalas temporales y determinó su relación con el clima y la sequía en dos bosques secos tropicales de Colombia (Tuluá) y Bolivia (INPA). A escalas intra-anuales se encontró que: (i) la reactivación del cambium y el crecimiento del xilema ocurre durante la época húmeda del año en ambos bosques. Esto refleja la influencia de las altas precipitaciones y los valores positivos del balance hídrico atmosférico en el desarrollo de las nuevas células del xilema. (ii) El período de crecimiento en Tuluá estuvo asociado a temperaturas bajas y, por ende, a un déficit de presión del vapor (DPV) bajo, mientras que en INPA la estación de crecimiento estuvo asociada a valores altos de temperatura y DPV. Sin embargo, en ambos sitios de estudio, las temperaturas altas registradas a lo largo del día afectaron negativamente el incremento radial a escalas horarias. Las especies pueden hacer frente a estas condiciones adversas, por ejemplo, restringiendo el crecimiento a períodos del día que registren temperaturas bajas, ya que la pérdida de agua asociada a la evapotranspiración también sería baja. A escalas inter-anuales se determinó que: (i) el crecimiento radial de todas las especies de INPA presentó una asociación positiva con la precipitación y el balance hídrico atmosférico y una relación negativa con la temperatura. Esto indica que todas las especies comparten una señal común de la variabilidad del crecimiento en respuesta al clima local. No obstante, la fuerza de la respuesta fue especie-específica. Esto indica que existe una sensibilidad diferencial entre las especies al clima. (ii) El crecimiento radial de todas las especies de INPA respondió positivamente al balance hídrico atmosférico durante la estación húmeda, pero esa respuesta fue diferente entre las especies en función de la densidad de la albura. La densidad de la albura fue negativamente relacionada a la variabilidad del crecimiento explicada por el balance hídrico. (iv) Las especies de INPA fueron resilientes a las sequías de corto plazo (estación seca anual), mientras que el crecimiento fue particularmente sensible a las sequías de larga duración (sequías multi-anuales), excepto en las especies con alta densidad de la albura.

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Aragão, José Roberto Vieira. "Ecologia da madeira e aspectos ecofisiológicos foliares de quatro espécies de florestas tropicais secas no estado de Sergipe." Universidade Federal de Sergipe, 2017. https://ri.ufs.br/handle/riufs/4479.

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Global climate change has severe consequences at various trophic levels, especially tree plant species. In regions of Tropical Dry Forests (TDF) these impacts are extreme and still little studied. This work evaluated how environmental conditions (local, regional and global), imminent climate changes, influenced the dendroecology, wood anatomy and foliar ecophysiology of four tree species occurring in the TDF of two sites, Sergipe, Grota do Angico Natural Monument, and in a remnant of TDF in Fazenda São Pedro, municipality of Porto da Folha, Sergipe. Samples of wood and leaves of six individuals of each species, Aspidosperma pyrifolium, Ziziphus joazeiro, Tabebuia aurea and Libidibia ferrea were randomly collected. For each individual, three wood samples were collected, two for dendroecology and one for the anatomy of the wood. Leaves, of the same plants were collected at both sites, in the dry and rainy periods, and intended for the ecophysiological analyzes. Collection data on species distribution (SpeciesLink project) were used in the construction of ecological niche models (ENM). Historical climate datas were obtained from INMET, AGRITEMPO, state data, the WolrdClim project, and the NOAA. The results of the dendroecological analyzes showed the formation of annual growth rings in the four species, that the chronologies of all the taxa have a significant relation with rainfall events in both sites, and some taxa had the chronologies related to the surface temperature of the Atlantic Ocean (TSA) and ENSO events, indicating a decrease in plant growth accompanied by lower rainfall volumes in the last decade. The ENM showed different responses of the species niche to the environmental variables (precipitation and temperature) in the TDF, with significant correlations with the anatomical and physiological data, and showed the occurrence of distinct functional groups among the taxa, changing as a function of the changes in the climate. The present study confirmed that the four TDF species have dendroecological potential for climate response, and that ENM's in line with functional (anatomical and physiological) traits analysis may be a viable solution to evaluate the responses of these taxa To xeric environments, in addition to serving as diagnoses of future global climate change, given its high correlation with the functional modifications of the species evaluated here.
As mudanças climáticas globais geram consequências severas em diversos níveis tróficos, em especial às espécies vegetais arbóreas. Em regiões de Florestas Tropicais Secas (FTS) estes impactos são extremos e ainda pouco estudados. Este trabalho avaliou como as condições ambientais (locais, regionais e globais), iminentes as mudanças do clima, influenciaram na dendroecologia, anatomia da madeira e ecofisiologia foliar de quatro espécies arbóreas ocorrentes na FTS de dois locais em Sergipe, no Monumento Natural Grota do Angico, e em um remanescente de FTS na Fazenda São Pedro, município de Porto da Folha, Sergipe. Foram coletadas aleatoriamente amostras de madeiras e folhas de seis indivíduos de cada espécie, Aspidosperma pyrifolium, Ziziphus joazeiro, Tabebuia aurea e Libidibia ferrea. Para cada indivíduo foram coletadas três amostras de madeira, duas destinadas a dendroecologia e uma a anatomia da madeira. Folhas, das mesmas plantas foram coletadas nos dois locais, nos períodos seco e chuvoso, e destinadas às análises ecofisiológicas. Dados de coleções sobre a distribuição das espécies (projeto SpeciesLink) foram utilizados na construção de modelos de nicho ecológico (MNE). Dados climáticos históricos foram obtidos das plataformas do INMET, AGRITEMPO, estações estaduais, do projeto WolrdClim, e do NOAA. Os resultados das análises dendroecológicas mostraram formação de anéis de crescimento anuais nas quatro espécies, que as cronologias de todos os táxons possuem relação significativa com eventos de chuva em ambos os locais, e alguns táxons tiveram as cronologias relacionadas com a temperatura da superfície do Oceano Atlântico (TSA) e eventos de ENOS, indicando diminuição no crescimento das plantas acompanhando menores volumes de chuvas na última década. O MNE mostrou diferentes respostas do nicho das espécies às variáveis ambientais (precipitação e temperatura) nas FTS, com correlações significativas com os dados anatômicos e fisiológicos, e mostraram a ocorrência de grupos funcionais distintos entre os táxons, se alteram em função das mudanças no clima. O presente estudo confirmou que, as quatro espécies no FTS possuem potencial dendroecológico de resposta ao clima, bem como que MNE’s em consonância com a análise de traços funcionais (anatômicos e fisiológicos) podem ser uma solução viável para avaliação das respostas destes táxons a ambientes xéricos, além de servir como diagnósticos das mudanças climáticas globais futuras, vista sua alta correlação com as modificações funcionais das espécies aqui avaliadas.

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Barrance, Adrian. "Farmers' relations with trees in the Mesoamerican Tropical Dry Forest : narratives and realities." Thesis, University of East Anglia, 2010. https://ueaeprints.uea.ac.uk/19905/.

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August-Schmidt, Elizabeth Melissa. "Mechanisms of Community Assembly Beneath N-Fixing Trees in a Hawaiian Dry Woodland." Thesis, University of California, Santa Barbara, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13423031.

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Nitrogen (N) fixing trees are commonly used to promote forest restoration in disturbed areas because they can quickly recreate forest canopy structure. That structure in turn is hypothesized to attract animal seed dispersers and create enough shade to reduce undesirable species (particularly grasses). Yet N-fixers tend to increase soil N availability, which could facilitate the spread of nitrophilous invasive species. This dissertation evaluates the long-term consequences for understory community composition of establishing three N-fixing tree species (Acacia koa, Sophora chrysophylla, and Morella faya) after exotic grass-fueled fire in the seasonally dry subtropical woodland in Hawaii. To understand the restoration potential of these species, I compared discrete single-species stands of N-fixing trees in burned areas to both an intact native woodland and burned, open sites with no tree cover. Although N-fixing species are often assumed to be ecologically similar, trait variation among N-fixing trees in this system was strong enough to differentiate understory communities among stands of the three N-fixer species. To understand the mechanisms driving differences in understory composition among site types, particularly among N-fixing trees, I characterized the abiotic environment created by these species in terms of light and N availability, both of which were important drivers of understory community composition. High light and N availability were associated with greater exotic species cover and unique exotic species. Surprisingly, N availability was highest and N cycled fastest beneath the relatively slow-growing S. chrysophylla despite having much lower litter-N inputs than the faster-growing A. koa and M. faya. In this study, fast N-cycling was associated with high specific leaf area, high foliar N content and low foliar lignin:N. These traits are consistent with fast leaf economic spectrum traits in the general ecological literature, but this approach has not previously been applied to distinguish among N-fixing trees. Native Hawaiian dry forest understory recovery, particularly that of woody species, was limited throughout the burned area regardless of canopy cover. To determine what limits native shrub recovery, I sampled the seed bank and recorded natural seedling germination. I also planted native seedlings into the understory of all site types and either removed or left intact the invasive grass grasses present in the understory. I found that native shrubs were limited by both seed availability and competition with exotic grasses. Although outplant survival did not vary by N-fixer species identity, differences in the mechanisms by which each N-fixing species limited native seedling survival likely play a role in understory community assembly long-term. When restoration occurs in the context of secondary succession, prioritizing the creation of forest structure using N-fixing trees, particularly open-canopied fast-cycling species, such as S. chrysophylla, could make full community recovery more difficult by promoting rather than suppressing exotic grasses.

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Rampazzo, Fabiano Pinheiro. "Estudo de viabilidade do sistema de ancoragem de uma unidade flutuante de produção e armazenamento \"FPSO\" acoplada a um sistema de completação seca \"TLWP\"." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-13072011-103539/.

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A produção de petróleo e gás em campos brasileiros é cada vez mais proveniente de regiões com águas profundas e situadas longe da costa, chegando a distâncias de mais de 100 km, como, por exemplo, na Bacia de Campos ou de Santos. Devido à falta de infra-estrutura e às características do petróleo desses campos, a cadeia de abastecimento e o sistema de exportação da produção possuem grande importância para a indústria offshore. Uma maneira usual para a exportação da produção é através de dutos submarinos, onde o óleo e/ou a gás flui das plataformas diretamente para o continente. Com esta infra-estrutura é possível a utilização de sistemas de produção sem capacidade de armazenamento e, conseqüentemente, torna-se desnecessário o uso de navios para o alívio da produção. No entanto, devido à qualidade do óleo e às distâncias entre os poços e a costa em alguns campos brasileiros, a utilização dos oleodutos mostra-se uma solução pouco viável. Por este motivo, é bastante comum o uso de FPSOs ou semi-submersíveis conectadas a sistemas auxiliares, como o FSO (Floating Storage and Offloading). Nas plataformas, outra característica importante e desejada é tornar viável o uso de um sistema de completação seca (árvore de Natal acima da linha dágua) com o objetivo de diminuir, significativamente, os custos operacionais envolvidos. Esse tipo de completação é utilizado, com excelência, por unidade do tipo TLWP ou Spar, devido ao baixo nível dos movimentos e acelerações observadas nestas plataformas. Entretanto, as condições ambientais severas amplificam as dificuldades para encontrar um sistema com grande capacidade de armazenamento e que permita o uso de completação seca. Neste contexto, pesquisadores e engenheiros estão sendo obrigados a desenvolver novos conceitos capazes de atender a essa demanda. Desta forma, uma nova solução, considerando um FPSO e uma TLWP operando a uma curta distância e trabalhando de forma acoplada com a conexão garantida por cabos sintéticos vem sendo estudada. Essencialmente, o grande atrativo deste conceito é o fato de que toda a produção e o armazenamento são concentrados no FPSO e a TLWP é responsável pela perfuração e extração dos hidrocarbonetos através de risers verticais. Assim o sistema trabalhando de forma conjunta possui capacidade de armazenamento e permite o uso da completação seca. Nesta dissertação, foi realizado um estudo sobre a evolução deste novo conceito, dividido em três fases. A primeira focada no dimensionamento do sistema de conexão e ancoragem das unidades e em uma investigação da interação hidrodinâmica entre as unidades de forma a mostrar a viabilidade do sistema. A segunda fase, focada na validação dos resultados por meio da comparação com os testes realizados no modelo em escala do NMRI (National Maritime Research Institute - Japão). Finalmente, a terceira fase, com foco no redimensionamento do sistema de amarração e no sistema de conexão, com base nos resultados obtidos na segunda fase.
The oil and gas production in Brazilian fields are commonly found in deep water and situated far away from the coast, reaching distances of more than 100 km as, for example, in the Campos Basin or Santos Basin. Due to the heavy oil and lack of pipeline infrastructure found in these fields, not only subsea equipments that must support high pressure but also logistics problems such as supply chain and production exportation system play an important role for the offshore industry. A usual way to export the production is to concentrate it in hubs of submarine pipelines which flows the oil or gas from the platforms to the continent. This infrastructure makes possible the use of no storage production systems and, consequently, releases the use of the shuttle tanks employment. However, due to the quality of the oil and the distances between the wells and the coast, some Brazilian fields do not allow the use of the pipelines to export their production. For this reason, is quite common to use FPSO and semi-submersible aided by auxiliary systems such as the FSO (Floating Storage and Offloading) units. Another important and desired characteristic of production platforms is to make it feasible to install a dry Christmas tree system aiming to decrease, significantly, operational costs involved. This feature is performed, with excellence, by TLWP and Spar units due to the low level of motions and accelerations observed in these platforms. Harsh environmental conditions can bring difficulties to find a solution of a system with both storage and dry tree system capability. In this context, researchers and engineers are being forced to develop new technological systems capable to support this demand. In this way, a new solution considering a FPSO and a TLWP coupled in a short distance by synthetic ropes has being studied. Essentially, the attractive feature of this concept is the fact that the production is performed by the FPSO whereas the TLWP is responsible to support the risers and drilling facilities turning the system coupled, equipped with a dry Christmas tree and with the possibility to storage the production. By now, the concept evolution has been divided in three phases. The first phase concerned about an advanced research focusing on the connection and mooring system development and the hydrodynamic interaction between the units and having in mind the verification of the concept feasibility. The second phase, concerned about the results validation by a comparison with scale model tests performed in the NMRI (National Maritime Research Institute Japan). Finally, the third phase, has the focus in the mooring and connection system resizing based on the results obtained on second phase.

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Cajas-Giron, Yasmin Socorro. "Evaluation of the role of trees and shrubs in seasonally dry pastures of Colombia." Thesis, Bangor University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394985.

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Kennedy, Byron David. "The liturgical role of the deacon in the present-day Byzantine Divine Liturgy a description and theological-liturgical inquiry /." Toronto, Canada : University of St. Michael's College, 2008. http://dx.doi.org/10.2986/tren.119-0001.

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Morris, Vincent E. "Eighth-day creators a Christian environmental stewardship ethic based on the "image of God" in the doctrine of creation /." Theological Research Exchange Network (TREN), access this title online, 2006. http://dx.doi.org/10.2986/tren.088-0149.

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Duffy, Brittany A. "Trees in the Agricultural Matrix: Reforestation Processes in a Tropical Dry Landscape in Chinandega, Nicaragua." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2608.

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Tree management practices in the tropical dry forest region of Nicaragua were examined to determine opportunities and factors influencing tree-planting initiatives and forest recovery within the agricultural matrix. A 217.11 ha tree inventory and 44 social surveys were conducted in three rural communities. The inventory found 88 species, 66.68% were native, and 70 valued for multiple uses. Farmers’ reasons for maintaining trees varied, emphasizing live fencing, wood, and fruit. The landscape also contains a tree plantation and a riparian forest, and the origins and management of these tree cover components of the landscape are also considered. Tree planting interventions should supplement extant stakeholder motivation with technical training and basic materials only as explicitly requested by participants, rather than imposing costly or inappropriate project preferences. Initiatives should also focus on smallholders and on multi-use native species suggested by stakeholders in order to maximize the economic, social and environmental benefits provided.

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Hasselquist, Niles Jacob. "Mycorrhizae, water, and a changing climate how do trees survive in a seasonally dry tropical forest? /." Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=105&did=1871852251&SrchMode=1&sid=1&Fmt=7&retrieveGroup=0&VType=PQD&VInst=PROD&RQT=309&VName=PQD&TS=1270484435&clientId=48051.

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Thesis (Ph. D.)--University of California, Riverside, 2009.
Includes abstract. Includes bibliographical references (leaves ). Issued in print and online. Available via ProQuest Digital Dissertations.

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Diaz, de Arends Miriam Leonarda. "Ecophysiology and phenology of very dry tropical forest trees : effects of soil characteristics, rainfall and irrigation." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624548.

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Jenkins, Seán E. "Spatial demography of trees in an oak savanna and adjacent dry chert woodland in the Missouri Ozarks /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9842585.

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Budd, Thomas Andrew. "True School| A 30-Day Community-Based Transformative Educational Program." Thesis, Sofia University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10751943.

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The aim of this study was is to uncover the interdependence between self-transformation and community participation through analyzing the self-reports of participants in a 30-day community-based transformative educational program called the True School, organized by the Konohana Family in Fujinomiya, Japan. This research explored the question: What conscious phenomena, in terms of self-awareness, were experienced through participating in a 30-day community-based transformative educational program called the True School? The Konohana Family is an intentional community located in Fujinomiya, Japan, whose cultural belief system is based on transcending ego. Daily journals and a critical hermeneutic conversation were used to explicate the conscious phenomena experienced. Some experiences that the participants aspired for were later felt, and some experiences that participants felt were later aspired for. The researcher found that, prior to the True School, participants experienced emotional conflicts and repressed their personal desires. They desired acceptance, personal ownership, transformation, and wisdom. They aspired to feel autonomy, confidence, creative expression, fulfillment, and vulnerability. During the True School, participants wanted to feel confidence, creative expression, and vulnerability. They experienced compassion, embodiment, empowerment, gratitude, intuition, joy, vulnerability, will, and wisdom. After the True School, participants felt acceptance, faith, joy, non-attachment, and wisdom. More so, locus of control (LoC), the belief in a source of control as internal or external, was found to modulate self-construal and worldview. LoC was considered to be synonymous with ego, as the belief in a separate self. When ego is intended to be acknowledged and suspended or transcended, harmony is experienced and community forms. This research addresses the significance for further applications of community-based learning environments, specifically with the intention of transcending ego.

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Rabo, Emmanuel Tsammani. "Response of dry season sorghum (Sorghum bicolor(L.) moench) to intercropping with trees in a semi-arid environment." Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318086.

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Raksanyi, Emil, and Erik Dackander. "A comparative study on one-day-ahead stock prediction using regression tree and artificial neural network." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-186499.

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Making good predictions for stock prices is an important task for the financial industry. The way these predictions are carried out is often by using artificial intelligence that can learn from the data using machine learning algorithms. This study compares three different approaches in this area, using a regression tree and two artificial neural networks with two different learning algorithms. The learning algorithms used was Levenberg-Marquardt and Bayesian regularization. These three approaches was evaluated using the average misprediction and worst misprediction they made in the selected interval from two different indexes, OMXS30 and S&P-500. Out of these three approaches the artificial neural networks outperformed the regression tree and the Bayesian regularization algorithms performed the best out of the two learning algorithms. The conclusions did support the usage of artificial neural networks but was not able to fully establish that the Bayesian regularization algorithm would be the best performing in the general case.

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Morgan, Jo-anne Mary. "Arboreal Eloquence: Trees and Commemoration." Thesis, University of Canterbury. Geography, 2008. http://hdl.handle.net/10092/1990.

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This thesis is about the use of trees for commemoration and the memory that they have anchored in the landscape. There has been little written on the use of trees for commemorative purposes despite its symbolic resonance over the last 150 years. To determine the extent to which commemorative trees have been employed, the social practice and context in which the trees were planted, field and archival work was undertaken in New Zealand and Australia. This has been supported with some comparative work using examples from Britain and the United States of America. The research also utilizes the new availabilities of records on-line and the community interests that placed historical and contemporary material on-line. The commemorative tree has been a popular commemorative marker for royal events, the marking of place and as memorial for war dead. It has been as effective an anchor of memory in the landscape as any other form. The memory ascribed to these trees must be understood in terms of the era in which the tree was planted and not just from a distance. Over time the memory represented by the trees and its prescribed meanings, has changed. For all its power and fragility, memory is not permanent but nor is it so ephemeral as to exhibit no robustness at all. Instead memory exists in a state of instability that leaves it open to challenge and to constant reassessment based on the needs of the viewing generation. This instability also allows the memory, and thus the tree, to fade and become part of the domestic landscape of treescape memories (Cloke and Pawson, 2008). However, in some circumstances trees are retrieved and reinscribed with specific memory and made relevant for a new generation. The landscape created by commemorative trees is, therefore, multifunctional, in which social relations support memory, remembrance, forgetting, silences, erasures, and memory slippage.

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CastanÌƒeda, HernaÌn Jair Andrade. "Growth and inter-specific interactions in young silvopastoral systems with native timber trees in the dry tropics of Costa Rica." Thesis, Bangor University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440956.

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Prno, Justin. "Celebrating the True North: Canada Day as Part of a Political Master Brand." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39055.

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In Canada, the rise of political branding coincided with the adoption of the permanent campaign, creating an environment in which politicking is now normalized and politicization is expected. With Canada Day 2017 as a case study, this thesis adopts Marland’s Branding Lens Thesis (2016) as a conceptual framework to analyze if a national holiday became part of the Liberal Party of Canada’s master brand. The key conclusion of this thesis is that the Liberals integrated their ‘master brand’ into Canada Day 2017 by integrating political branding into their government communications. This thesis also shows that Justin Trudeau played a bigger role during Canada Day than expected by a Prime Minister. Significantly, this thesis shows the Liberal government altered the themes and messaging of Canada 150 to parallel that of their master brand, applying a Liberal tint to Canada Day and Canada 150.

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Kelly, Alison M. "Predictively Mapping the Plant Associations of the North Fork John Day Wilderness in Northeastern Oregon Using Classification Tree Modeling." DigitalCommons@USU, 1999. https://digitalcommons.usu.edu/etd/6572.

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Shifting perspectives on restoration and management of public lands in the inland West have resulted in an increased need for maps of potential natural vegetation which cover large areas at sufficient scale to delineate individual stands . In this study, classification tree modeling was used to predictively model and map the plant association types of a relatively undisturbed wilderness area in the Blue Mountains of northeastern Oregon. Models were developed using field data and data derived from a geographic information system database. Elevation, slope, aspect, annual precipitation, solar radiation, soil type, and topographic position were important predictor variables. The model predicted plant association types with a relatively high degree of accuracy for most plant association types, with the lowest accuracy for the types within the grand fir series. Fuzzy confusion analysis was used to analyze model performance, and indicated the overall model accuracy was 72%.

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Brodersen, Craig Robert. "Photosynthetic carbon gain on an episodically dry year in Abies lasiocarpa and Picea engelmannii across a treeline ecotone /." Electronic thesis, 2003. http://etd.wfu.edu/theses/available/etd-12032003-171104/.

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Lezzer, Paolo <1980&gt. "Architectural development and dry matter production in a multisite trial on single and multiaxis apple trees (Malus domestica Borkh) grafted on different rootstocks." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3969/.

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In two Italian sites, multiaxis trees slightly reduced primary axis length and secondary axis length of newly grafted trees, and increased the number of secondary shoots. The total length, node production, and total dry matter gain were proportional to the number of axis. Growth of both primary and secondary shoots, and dry matter accumulation, have been found to be also well related to rootstock vigour. A great variability in axillary shoot production was recorded among different environments. Grafted trees had higher primary growth, secondary axis growth, and dry matter gain than chip budded trees. Stem water potential measured in the second year after grafting was not affected by rootstocks or number of leaders. Measurements performed in New Zealand (Hawke’s Bay) during the second year after grafting revealed that both final length and growth rate of primary and secondary axis were related to the rootstock rather than to the training system. Dwarfing rootstocks reduced the number of long vegetative shoots and increased the proportion of less vigorous shoots.

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Avermann, Niklas, and Jan Schlüter. "Determinants of customer satisfaction with a true door-to-door DRT service in rural Germany." Elsevier, 2019. https://publish.fid-move.qucosa.de/id/qucosa%3A72228.

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The effects of demographic change and the lack of acceptance represent some of the main problems for the public transport infrastructure in rural areas. As a consequence, the development of new transport service options becomes especially relevant for rural communities. The Max-Planck-Institute for Dynamics and Self-Organization developed a new form of Demand Responsive Transport the EcoBus to examine the viability of new DRT systems in rural Germany. Our work draws on customer satisfaction data during the trial runs of the EcoBus. Based on the survey data, this paper develops regression models to explain the determinants of DRT customer satisfaction. Our main findings include the importance of waiting times and the ease of entry for overall customer satisfaction. Nevertheless, we found no evidence that the presence of other guests in the vehicle had any negative impact on customer satisfaction. Findings of other works that women are significantly more likely to use DRT services could not be validated from our data.

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Story, Kathleen Ann. "Arbor Day curriculum unit for grades kindergarten through grade six." CSUSB ScholarWorks, 1992. https://scholarworks.lib.csusb.edu/etd-project/705.

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Newman, Kelly D. "To know the only true God : reconciling the God of the Old Testament with the God of the New Testament /Kelly D. Newman." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1345.pdf.

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Selvik, Amalie Marie. "Å dra blikket ned mot bakken - Naturvitenskapelig tenkning, geologi, estetisk fantasi og antroposen bekymring : En undersøkelse av tre kunstinstallasjoner av Toril Johannessen." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for nordistikk og litteraturvitenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-21528.

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GÓMEZ, MIRANDA AIDA. "EVALUACIÓN DE TRES VARIEDADES DE GRAMÍNEAS PARA PASTOREO EN SISTEMAS DE PRODUCCIÓN DE LECHE EN PEQUEÑA ESCALA EN EL NOROESTE DEL ESTADO DE MÉXICO." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2016. http://hdl.handle.net/20.500.11799/66386.

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Los cambios importantes en el mercado de la leche, asociados a los episodios de crisis económicas han transformado las estrategias de alimentación para reducir costos, así como la integración en la cadena de valor de los pequeños productores. El objetivo de este trabajo fue el evaluar el rendimiento productivo de vacas lecheras bajo pastoreo intensivo como una alternativa para la utilización en sistemas de producción de leche en pequeña escala, utilizando tres variedades de gramíneas (Festulolium Spring Green, Bromo catártico cv Matua y ballico perenne cv Pay Day). Se realizó un experimento con tres vacas bajo un arreglo de cuadro latino 3x3, con periodos experimentales de 14 días cada uno, los tratamientos evaluados fueron: PD= Pastoreo en pradera de Lolium perenne cv Pay Day, FSG= Pastoreo en pradera Festulolium cv Spring Green y BM= Pastoreo en pradera de Bromus catharticus cv Matua (BM), en todos los tratamientos las vacas fueron suplementadas con 5 kg de concentrado comercial. Las variables evaluadas en las praderas fueron acumulación neta de forraje (ANF), altura de la pradera, además de los análisis fisicoquímicos del forraje. En la respuesta productiva se evaluó el rendimiento de leche, el peso vivo de las vacas y la condición corporal. Los resultados obtenidos La ANF promedio de las praderas fue de 343.9kg MS/ha, con una ANF por día de 24.56 kg/MS, con una composición química (PC, MO, FND, FAD) similar a lo reportado por la literatura para las variedades estudiadas, con una baja digestibilidad, pero un contenido energético aceptable. Las variables medidas (grasa, proteína y lactosa) para la composición química de la leche no representaron diferencias estadísticamente significativas (P>0.05), los valores de Nitrógeno Ureico en Leche (NUL) reportados estuvieron dentro de los niveles óptimos de nitrógeno en leche (rango de 12-15mg/dL). Los resultados obtenidos para los parámetros productivos en cuanto a rendimiento de leche fue una diferencia (P<0.05), para BM con un 9% menor rendimiento en comparación con PD Y FSG. Sin encontrar diferencias significativas (P<0.05) en el Peso Vivo y Condición Corporal.

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Newman, Kelly D. "To Know the One True God: Reconciling the God of the Old Testament with the God of the New Testament." BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/471.

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There is a popular misconception in the world that Jehovah is too severe on occasion while Jesus Christ is always kind and merciful. The Latter-day Saint belief that Jehovah and Jesus are the same person presents a supposed conflict. There has not been much written on this subject by either non-Latter-day Saints or Latter-day Saints, thus, this thesis represents a unique contribution to a common perception prevalent in many Christian circles. The research of this thesis shows that the misconception is based on three problems: first, a misinterpretation of biblical stories in both the Old and New Testament; second, a lack of understanding biblical context and culture; and third, a lack of applying modern revelation to this subject. The research of this thesis focuses on these three areas in an effort to resolve this false perception. This thesis takes a deeper look into the acts of Jehovah and Jesus Christ as found in the Old and New Testaments respectively. Next, it looks as several doctrines related to this subject that have been revealed through latter-day prophets and incorporates them into the Old Testament. This analysis paints a broader picture of the Lord and illustrates that He was, indeed, merciful in the Old Testament but, at times, severe in the New Testament. Lastly, this thesis takes four of the most difficult Old Testament stories that seem to represent Jehovah as harsh, capricious, and unyielding, and puts them in their cultural setting. Though not every act can be completely explained, there is a high degree of similarity between Jehovah and Jesus. The study concludes, therefore, that much of the problem lies with perception and not with reality.

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Perrimond, Benoît. "Les variations climatiques régionales observées et potentielles à l'échelle de 2 zones ateliers : Alpes et Armorique." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAU008/document.

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Les interactions climat-environnement sont susceptibles d’être profondément modifiées du fait du changement climatique observé au cours des dernières décennies, et de celui prévu pour le moyen terme. Dans cette thèse, deux Zones Ateliers du CNRS (ZA Alpes et ZA Armorique), espaces spécifiques pour l’analyse des relations Hommes-Milieux, sont privilégiées pour une étude d’impact des variations climatiques sur certains facteurs de l’environnement végétal. L’objectif de cette thèse est de déterminer la variabilité spatio-temporelle du climat et de la phénologie afin de pouvoir tester la reproductibilité de l’influence du premier facteur sur le second, en caractérisant certains comportements soumis aux principales contraintes climatiques.L’analyse de séries stationelles et des réanalyses issues de Météo-France s’effectue par le biais de méthodes statistiques pour isoler les principales tendances, ruptures et modes de variabilité spatio-temporelle observés sur deux variables climatiques (température et cumuls pluviométriques) sur la période contemporaine (1959-2009). Cette dernière permet de mettre en avant une rupture thermique significative pour l’année 1987 avec une augmentation (plus marquée en Armorique) de l’ordre de 1°C. Les précipitations montrent une modification de leur mode de variabilité interannuelle, avec un allongement des alternances de périodes sèches et humides passant de 6-8 ans après les années1990, contre 2-4 ans avant. Leurs influences sur la végétation sont suivies grâce à l’étude de la phénologie saisonnière de la principale formation végétale naturelle présente dans les deux ZA, soit les espaces forestiers caduques.Des données bioclimatiques issues de l’Observatoire des Saisons ainsi que des traitements analytiques à partir de données issues de la télédétection satellitaire (SPOT-VGT et MODIS) permettent de mieux définir la variabilité spatio-temporelle de la phénologie forestière alpine et armoricaine. Un essai de modélisation statistique des liens climat-phénologie est ensuite proposé par le biais d’un modèle degré-jour, calibré et validé avec l’aide des données insitutionnelles et issues de la télédétection. Le forçage final est réalisé avec des données de prévisions climatiques obtenues parle modèle ALADIN sur une période temporelle proche (2021-2050), montrant une certaine modification des paramètres climatiques, comme une augmentation de la température d’environ 1°C et une diminution des précipitation de l’ordre de 100 mm en Armorique. Les résultats provenant de la modélisation statistique permettent d’observer une avancée des stades de feuillaison pour les deux zones d’études en fonction de conditions bioclimatiques potentielles attendues dans les deux espaces d’étude. Néanmoins, ces résultats soulèvent aussi la question des rétroactions dynamiques entre la végétation et le climat, analyses non abordées dans cette thèse
Climate change occuring during last decade will deeply modify climate and environnemental interaction. Inthis PhD, two sites of European Lon-Term Ecosystem Research Network (French Alps and Britany), specializedin human/nature relationships and environnmental studies were selected for analyzing phenological impact withclimate change constraint. The aim of this work is to determine the spatio-temporal variability of climate andphenology over both sites and to predict the response of forestry phenology under climate change constraint.Meteorological spatio-temporal variability is explained from Météo-France time series analyses and also withclimate reanalysis on the 1959-2009 period. Temperature and precipitation appeared to be best climatologicalvariable to discrimine the impact on vegetation. Since 1987, a significant temperature increase of about 1°C appears(less in the Alps and more in Armorics). Precipitation temporal variability appeared to change near year 1990with a quasi-biennial periods before and with a 6-8 year period after 1990. Phenology is used to monitor naturalforestry dynamics and the feedback on climate on vegetation. Bioclimatics data from « Observatoire des Saisons »and determined from remote sensing data (SPOT-VGT and MODIS datasets) are used to follow spatio-temporalvariability of the phenology. Relationships between climate and phenology are determined by statistical modelisation(degree-day model). SAFRAN-France data and phenological remote sensing data are combined to calibrate and tovalidate of the model in present time. Climate forecast from ALADIN model are used to execute the model on afutur period (2021-2050) with an thermal increase condition of around 1°C and a diminution of precipitation inArmorics (100 mm). Degree-day model predict an advance of growth phase over both site according to climateforcing

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Nyh, Johan. "From Snow White to Frozen : An evaluation of popular gender representation indicators applied to Disney’s princess films." Thesis, Karlstads universitet, Institutionen för geografi, medier och kommunikation, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-36877.

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Simple content analysis methods, such as the Bechdel test and measuring percentage of female talk time or characters, have seen a surge of attention from mainstream media and in social media the last couple of years. Underlying assumptions are generally shared with the gender role socialization model and consequently, an importance is stated, due to a high degree to which impressions from media shape in particular young children’s identification processes. For young girls, the Disney Princesses franchise (with Frozen included) stands out as the number one player commercially as well as in customer awareness. The vertical lineup of Disney princesses spans from the passive and domestic working Snow White in 1937 to independent and super-power wielding princess Elsa in 2013, which makes the line of films an optimal test subject in evaluating above-mentioned simple content analysis methods. As a control, a meta-study has been conducted on previous academic studies on the same range of films. The sampled research, within fields spanning from qualitative content analysis and semiotics to coded content analysis, all come to the same conclusions regarding the general changes over time in representations of female characters. The objective of this thesis is to answer whether or not there is a correlation between these changes and those indicated by the simple content analysis methods, i.e. whether or not the simple popular methods are in general coherence with the more intricate academic methods.

Betyg VG (skala IG-VG)

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Butz, Jan Philipp. "Tree Water Use Strategies in a Neotropical Dry Forest." Doctoral thesis, 2019. http://hdl.handle.net/21.11130/00-1735-0000-0005-126F-B.

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Nath, Cheryl D. "Tree Diameter Growth : Variations And Demographic Niches In A Tropical Dry Forest Of Southern India." Thesis, 2007. http://hdl.handle.net/2005/577.

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Tree growth influences forest community dynamics and responses to environmental variations, but currently is not well understood. Tree growth in highly diverse wet tropical forests have been well studied and characterised compared to the species-poor dry tropical forests. Thus, it is not clear if growth rates and community dynamics of dry forests are similar to those of wet forests, given the longer dry season, greater rainfall variability, more open canopy and lower number of species in dry forests. This thesis focuses on identifying important factors that influence tree diameter growth rates in the dry tropical forest at Mudumalai, southern India, and also compares growth patterns at this dry forest with those at moister forests. The thesis thus contributes towards closing the gap in understanding of tree growth patterns across the tropics. An initial analysis involving matrix-based population projections of four common canopy species at Mudumalai showed that variations in diameter growth have the potential to drastically modify population trajectories of dominant species. Thus the main focus of this thesis is aimed at identifying the important intrinsic and extrinsic factors affecting growth in this dry forest, as this information could be useful for future management of the forest. The second important aim of the thesis was to find out if growth rates are influenced by different sets of factors in tropical dry versus moist forests. A large permanent 50ha plot vegetation monitoring plot was set up in 1988-89 in the Mudumalai dry deciduous forest, and was subsequently monitored annually by staff of the Centre for Ecological Sciences. Data used in this thesis represent a 12-year interval between 1988 and 2000. Girth measurements were obtained from all woody tree stems ≥1cm in diameter every four years during this 12 year interval, which provided three census intervals of diameter increment data on >13,000 trees. For the comparison between dry and moist deciduous forests, data were obtained from a similar large plot maintained and monitored at the Barro Colorado Island (BCI) in Panama. Influences of the intrinsic factors, tree size, individual identity, species identity and growth form, were examined using t-tests, Wilcoxon signed ranks tests, linear regressions, analysis of variance (ANOVA), principal components analysis (PCA) and cluster analysis. Among the intrinsic factors tested, species identity explained approximately 20% of growth rates at the community level, while tree diameter explained less of growth variation, and growth form had a minor influence on growth. Growth rates also were examined for variations across the three census intervals, and for relationships with rainfall and survival from fire. Statistical tests included t-tests, Wilcoxon and other non-parametric sign tests, logistic regression and ANOVA. Most species and individuals showed significant reductions of growth in the second census interval (1992-1996), and growth rates of most trees were positively related to rainfall. Growth rate variations generally were not related to survival from fire, and few species were capable of escaping fire mortality by fast growth. Spatial environmental influences were tested in the commonest fifteen species, using five habitat categories, local elevation, slope, aspect, and the biotic neighbourhood variables of local conspecific and heterospecific density. Statistical tests included analysis of covariance, multiple linear regression and redundancy analysis. The tests were quadrat-based or individual-based, and species' growth responses were tested at different levels of distance and spatial scale. Topographic features and habitat categories had ephemeral effects on species growth. Only the most dominant species, Lagerstroemia microcarpa, showed consistent conspecific neighbour density effects. Redundancy analysis using a subset of common species and environmental factors did not reveal common growth responses to spatial environmental factors. Comparison of factors influencing growth at Mudumalai versus at BCI using multiple factor ANOVA and multiple linear regressions showed a similar influence of temporal variation at the two sites, but stronger and more widespread influence of tree size (diameter) at BCI. The greater influence of tree size at BCI may be related to greater light limitation in this dense moist forest. Spatial environmental factors had weak influences at both plots. Species were less differentiated from each other at the more diverse BCI plot compared to the relatively species-poor Mudumalai plot, suggesting that species' growth niches may be weakly related to diversity across tropical forests. Overall the results showed that among the factors tested species identity and census intervals were the most important influences on diameter growth at the Mudumalai dry deciduous forest. Tree diameter was less important and less consistent in affecting growth at the Mudumalai dry forest, contrary to expectations based on moist tropical forests where this relationship has been established previously. When comparing Mudumalai and BCI, the relative importance of different factors was different at the two sites, and the most important difference was a dominant influence of light limitation at the wetter forest in Panama. In terms of management applications, this study showed that fires at Mudumalai might be an inescapable source of mortality for many vulnerable species, and improved fire management is crucial for long term survival of species in this dry forest. At a larger scale, light and other environmental variables were found to influence growth differently at Mudumalai compared to BCI. This suggests that location-specific responses may be important for projections of tree biomass and carbon sequestration, especially under future climatic change scenarios.

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Dissertations / Theses on the topic 'Dry tree'

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