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Dissertations / Theses on the topic 'Patch-size'

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Published: 4 June 2021

Last updated: 17 June 2025

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DiBari, John Nicholas. "Linking patch dynamics, landscape organization, patch-size scaling, and landscape connectivity." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/280167.

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Over time, small local disturbances may result in large regional changes in landscape structure and function. For example, lightning strikes may lead to large-scale wildfire or land clearing to urbanization. In either case, landscape patterns change as the type and distribution of landscape elements change in response to disturbances. Additionally, changes in landscape patterns often affect ecological processes. For example, wildfires and urbanization affect succession and productivity, which changes the distribution of habitat features, and which may affect landscape connectivity for species inhabiting the landscape. I used rank-size distributions and their scaling exponents to illustrate landscape character and change in Yellowstone National Park and a portion of the metropolitan area of Tucson, Arizona, through patterns associated with the distribution of patch size. I found that natural and anthropogenic disturbances affected landscape organization similarly and thus produced similar distributional patterns of patch size. However, the magnitude of change created by natural and anthropogenic disturbances differed. Fires in Yellowstone National Park produced scaling exponents >1, suggesting that large patches affected the distribution of patch size disproportionately. Comparatively, urbanization in the Tucson metropolitan area produced scaling exponents ≈1, suggesting that large and small patches affect the distribution of patch size proportionately. To link changes in landscape patterns with changes in ecological processes I compared four commonly used landscape metrics with rank-size distributions and their scaling exponents. Rank-size distributions described the scaling properties of the landscape with regard to patch size, whereas other metrics did not. This is meaningful because there is an integral relationship between scaling properties of the landscape and scaling properties of species using the landscape. A species may perceive a landscape as connected when the patch-size characteristics of the landscape scale proportionally with the body-size characteristics of the species. As a result, the species may be more likely to move through and therefore persist in that landscape. I develop a theoretical relationship between natural and anthropogenic disturbances, describe landscape organization, and link landscape and species scaling characteristics.

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Butcher, Jerrod Anthony. "Minimum patch size thresholds of reproductive success of songbirds." Thesis, [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2842.

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Elsdon, Michael. "An investigation of reduced size planar fed microstrip patch antennas." Thesis, Northumbria University, 2005. http://nrl.northumbria.ac.uk/1183/.

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The primary goal of this research work is to investigate the use of slot loading in reduced size planar fed microstrip patch antennas and develop new antenna structures based on this technique. At present, little theoretical investigation or design methodology exists to support the design of compact structures and research in this field is largely empirical. Moreover, little work exists on the use of planar fed designs. This necessitates a primary requirement to firstly address this knowledge gap. To facilitate this, a mathematical modelling technique that can be applied to such structures is developed. This is based upon the segmentation and Green's function approach. Using this model, the performance of slot loaded structures in terms of circuit characteristics including resonant frequency, input impedance, and Q factor is determined. Using this knowledge, a design procedure is established and subsequently used to provide a framework for the design of novel slot loaded antennas for specific applications. Several new slot loaded patch antenna configurations are designed that produce size reduction whilst allowing the use of a planar feed. The validity of the designs are confirmed through the use of commercial full-wave modelling software package Ensemble. Three linear polarised antennas are presented which are shown to achieve size reduction of 12, 40 and 55% respectively. Several compact circular polarised antenna structures are successfully implemented producing size reduction of up to 43%. A novel design for a reduced size antenna with a dual frequency response is also presented with a tuneable frequency ratio of between 1.03 — 2.0. Prototypes of the aforementioned antennas are fabricated and tested, and practical results are shown.

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Waung, I.-Hui. "Effect of patch-size and habitat-edges on intertidal distributions of microgastropods." Thesis, The University of Sydney, 2006. https://hdl.handle.net/2123/28116.

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With increasing human activity and urban development along coastal areas, much research has recently focussed on examining how fragmentation of habitats affect marine fauna in near-shore environments. This study examines relationships between density of populations and patch-size and the effect of edges of habitat on distributions of minute gastropods (microgastropods) living in patches of coralline algae on intertidal shores in south-eastem Australia.

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Minor, Jesse, Donald Falk, and Greg Barron-Gafford. "Fire Severity and Regeneration Strategy Influence Shrub Patch Size and Structure Following Disturbance." MDPI, 2017. http://hdl.handle.net/10150/624330.

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Climate change is increasing the frequency and extent of high-severity disturbance, with potential to alter vegetation community composition and structure in environments sensitive to tipping points between alternative states. Shrub species display a range of characteristics that promote resistance and resilience to disturbance, and which yield differential post-disturbance outcomes. We investigated differences in shrub patch size and stem density in response to variations in ﬁre severity, vegetation community, and post-disturbance reproductive strategies in Sky Island forested ecosystems in the southwestern United States. Patterns in shrub structure reﬂect the effects of ﬁre severity as well as differences among species with alternate post-ﬁre reproductive strategies. Increased ﬁre severity correlates with larger patch sizes and greater stem densities; these patterns are observed across multiple ﬁre events, indicating that disturbance legacies can persist for decades. High severity ﬁre produces the largest shrub patches, and variance in shrub patch size increases with severity. High severity ﬁre is likely to promote expansion of shrub species on the landscape, with implications for future community structure. Resprouting species have the greatest variability in patch structure, while seeding species show a strong response to disturbance: resprouting species dominateatlowdisturbanceseverities,andobligateseedersdominatehighseverityareas. Differential post-ﬁre reproductive strategies are likely to generate distinct patterns of vegetation distribution following disturbance, with implications for community composition at various scales. Shrub species demonstrate ﬂexible responses to wildﬁre disturbance severity that are reﬂected in shrub patch dynamics at small and intermediate scales.

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Bellehumeur-Genier, Olivier. "Permafrost Patch Size Near the Margins of Discontinuous Permafrost, Southern Yukon and Northern B.C." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34969.

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This research focused on measuring permafrost patch size and related variables between Fort St. John, BC and Whitehorse, YT. Methods used included electrical resistivity tomography, climate monitoring, active layer measurement, analysis of historical aerial photos, and on-site near-vertical aerial imaging. Where permafrost is present along the transect, mean annual air temperature (2010-2014) varied from -3.3 ºC to -0.9 ºC, mean annual ground surface temperature from 0.7 ºC to 2.4 ºC and mean annual ground temperature from -0.3 ºC to 0.2 ºC (at TTOP). Permafrost patches are in the order of 10 – 50 000 m2 in area and there is a strong positive log-log relationship between patch area and maximum permafrost thickness. A conceptual model of permafrost patch size evolution under a warming climate is proposed. It is concluded that permafrost patch size depends on site-specific characteristics, the time since permafrost began to degrade and the local climate conditions.

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Towers, Naomi M. "Invertebrate community structure along a habitat-patch size gradient within a bog pool complex." Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/435.

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This thesis characterises species richness and community structure over a habitat-patch size gradient of a typical bog-pool complex, investigating the effect of pool size on aquatic invertebrate communities. In this study, twenty-two pools were surveyed ranging in area from 8.6 m2 to 280.9 m2 within a single complex at Forsinard in the north of Scotland. Three different sampling methods were used: baited and unbaited activity traps and a sediment sampler. Univariate and multivariate methods were used to investigate the effects of pool size and pool location within the complex on species richness and community structure. The research expands our knowledge of peatland pool invertebrates by providing a comprehensive survey of the aquatic invertebrate fauna representative of the Flow Country of northern Scotland. Two IUCN British Red Data Book species were recorded: the Northern Damselfly, Coenagrion hastulatum (Charpentier), and the cased caddisfly, Nemotaulius punctatolineatus (Retzius). Three species of aquatic Coleoptera were collected that have Nationally Notable status according to Ball (1986): Dytiscus lapponicus Gyllenhal, Ilybius aenescens Thomson and Gyrinus minutus Fabricius. All these species are typical of, and often restricted to, this habitat type. The three different sampling methods differed in their sampling efficiency and each gave a different species spectrum. A distinct seasonal change in the samples was also observed. The number of taxa caught per standardised sampling unit (taxon density) was investigated over the pool size gradient. Relationships between taxon density and area were weak or non-existent in both unbaited activity traps and sediment samples. However, the number of beetle species caught in baited activity traps increased significantly with pool size, indicating that the total number of beetle species per pool may also increase over the size gradient. Ratios of the number of predator taxa to prey (non-predator) taxa for each pool ranged from 0.34 to 0.78 with a mean of 0.49 and were not affected by pool area or total taxonomic richness. Taxa displayed a positive abundance-occupancy relationship and the possible underlying mechanisms involved in creating this pattern are discussed. Multivariate techniques showed that pool area, depth, and distance from the centre of the pool complex (periferality) all had a small but significant affect on community composition and that between certain taxa there were distinctly different optima along the pool size gradient. These results are discussed in the context of species area theory.

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Noran, Julia. "EFFECTS OF PATCH SIZE AND MATRIX TYPE ON BIRD ASSEMBLAGES WITHIN CENTRAL FLORIDA CYPRESS DOMES." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2963.

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The numerous studies on the effects of patch size on bird assemblages have produced varied results. I studied the effects of patch size and surrounding matrix on bird assemblages within central Florida cypress domes. My null hypothesis was that bird assemblages within cypress domes are unaffected by dome size or development in the matrix around the dome. My alternative hypothesis was that differences in bird assemblages are correlated with size and the degree of development within the matrix. I classified a pool of over a thousand domes according to three size categories and four matrix types. Three representatives for each combination of size and matrix were spot mapped for birds from May through August 2005. I examined the relationship of species richness and bird guilds to patch size and surrounding matrix. I also measured a series of potential covariates for each dome to account for variation among the three size-matrix representatives for each combination. Richness and abundance counts were divided by the number of listening points to standardize the data by effort. I found that the standardized species richness of bird assemblages significantly increased with the patch size of cypress domes; however, matrix and the interaction effect of size and matrix on overall standardized species richness were not significant. Significant covariates included percent of the buffer undeveloped, percent herbaceous cover, and the number of listening points per unit area. A linear regression tested for significant effects of log area and matrix on standardized species richness. Matrix was not significant, but log area did have a significant effect on standardized species richness. The MANOVA tests for guild richness data indicated no significant effects of dome size, matrix, or their interaction effect on diet, foraging, or location guilds. There were no significant main or interaction effects on any individual guilds in the ANOVA output. Individual backward linear regressions done on each guild indicated that matrix did not have significant effects on any guild, but log area had significant effects on ground foragers, lower-canopy foragers, omnivores, herbivores, and edge species. I then investigated the effects of size and matrix on standardized guild abundance. Dome size and matrix significantly effected diet guild abundance, but the size-matrix interaction did not. Dome size significantly affected insectivores, omnivores, and carnivores. Matrix had a significant effect on omnivores, herbivores, and carnivores. The size and matrix interaction had a significant effect on carnivores. Dome size and matrix significantly affected foraging guild abundance, but the size-matrix interaction did not. Dome size significantly affected ground, lower- and upper-canopy foragers. Matrix had a significant effect on ground, water, and upper-canopy foragers. The size and matrix interaction was not significant for any foraging guild. Dome size and matrix significantly effected location guild abundance, but the size-matrix interaction did not. Dome size significantly affected edge and interior species. Matrix had a significant effect on edge and interior species. The size and matrix interaction was not significant for any location guild. The relationship between species richness and habitat area is well-documented, and the results of this study were consistent with the expectation of higher species richness in larger areas. If maintaining high species richness is the sole goal of conservationists, then large habitat fragments would be preferable regardless of surrounding matrix. Nevertheless, species richness alone is not informative of the potential effects of patch size and matrix on the composition of an avian assemblage. Guild analysis gives insight into community structure and should be considered in addition to simple measures of species richness. Patch size and matrix type significantly affected a number of guilds, and several factors could contribute to the observed differences in guilds across patch size categories and matrix types. Different habitats are available to birds in domes of each size class and matrix type. The potential for diverse foraging opportunities increases as domes increase in size and change in relation to their surrounding matrix. A more detailed analysis is needed to determine how differences in vegetation of domes and surrounding matrix affect guilds, members of which may use habitats both within domes and the matrix. Cypress domes in the central Florida area face severe alteration or destruction due to rapid development. Long-term research that focuses on domes before and after development is needed to understand how changes in the matrix or size of the domes affect all resident flora and fauna. A variety of taxa and biogeochemical processes should be researched. Domes are naturally highly variable in size, shape, and structure, and development changes all of these characteristics. Conservation biologists and managers urgently need to determine how development affects cypress domes and what can be done to maintain their characteristic biodiversity. M.S. Department of Biology Arts and Sciences Biology

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Johnson, Linda Gail. "Effects of habitat patch size and isolation on the population structure of two siphonarian limpets." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1005364.

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Habitat fragmentation is a fundamental process that determines trends and patterns of distribution and density of organisms. These patterns and trends have been the focus of numerous terrestrial and marine studies and have led to the development of several explanatory hypotheses. Systems and organisms are dynamic and no single hypothesis has adequately accounted for these observed trends. It is therefore important to understand the interaction of these processes and patterns to explain the mechanisms controlling population dynamics. The main aim of this thesis was to test the effect of patch size and isolation on organisms with different modes of dispersal. Mode of dispersal has previously been examined as a factor influencing the effects that habitat fragmentation has on organisms. Very few studies have, however, examined the mode of dispersal of marine organisms because it has long been assumed that marine animals are not directly influenced by habitat fragmentation because of large-scale dispersal. I used two co-occurring species of siphonariid limpets with different modes of dispersal to highlight that not only are marine organisms affected by habitat fragmentation but that they are affected in different ways. The two species of limpet, Siphonaria serrata and Siphonaria concinna, are found within the same habitat and have the same geographic range along the South African coastline, however, they have different modes of dispersal and development. The effect of patch size on organism density has been examined to a great extent with varied results. This study investigated whether habitat patch size played a key role in determining population density and limpet body sizes. The two species are found on the eastern and southern coasts of South Africa were examined across this entire biogeographic range. Patch size was found to have a significant effect on population density of the pelagic developer, S. concinna, but not the direct developing S. serrata. Patch size did play a role in determining limpet body size for both species. S. concinna body size was proposed to be effected directly by patch size whilst S. serrata body size was proposed to be affected indirectly by the effects of the S. concinna densities. The same patterns and trends were observed at five of the seven examined regions across the biogeographic range. The trends observed for S. concinna with respect to patch size conform to the source-sink hypothesis with large habitat patches acting as the source populations whilst the small habitat patches acted as the sink populations. Many previous studies have focused on the effects of habitat patch size at one point in time or over one season. I tested the influence of habitat patch size on the two species of limpets over a period of twelve months to determine whether the trends observed were consistent over time or whether populations varied with time. S. concinna showed a consistently significant difference between small and large patches; whilst S. serrata did not follow a consistent pattern. The mode of dispersal for the two limpets was used to explain the different trends shown by the two species. This examination allowed for the determining of source and sink populations for S. concinna through the examination of fluctuations in limpet body sizes and population densities at small and large habitat patches over twelve months. The direct developing S. serrata trends could not be explained using source-sink theory, as populations were independent from one another. S. serrata demonstrated body size differences at small and large patches which, may be explained by interspecific and intraspecific competition. Habitat isolation is known to play an important role in determining the structure of assemblages and the densities of populations. In this study the population density of the pelagic developing S. concinna showed a weak influence of degree of isolation whilst that of the direct developing S. serrata did not, which may be because of habitat patches along the South African coastline not having great enough degrees of isolation. The population size-structure was influenced directly influenced by isolation for S. concinna, whilst the different population size structure for S. serrata may be explained by assemblage co-dependence. The mode of dispersal showed effects on the relationship of population density and population size-structure with habitat size and isolation. This study indicates the importance of investigating patterns and processes across a range of spatial and temporal scales to gain a comprehensive understanding of factors effecting intertidal organisms.

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Mendes, Calebe Pereira [UNESP]. "Patch size, shape and edge distance influences seed predation in a keystone palm in tropical rainforests." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/122104.

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Made available in DSpace on 2015-04-09T12:28:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-04-25Bitstream added on 2015-04-09T12:48:19Z : No. of bitstreams: 1 000814781.pdf: 508841 bytes, checksum: 114537088394da2fa462089c26ce1a78 (MD5) A predação de sementes é um importante tipo de processo ecológico, que afeta a abundância, diversidade e distribuição de espécies vegetais. Uma vez que esse processo ecológico depende da presença, abundancia e comportamento dos predadores de sementes, o que é afetado pelas características da paisagem, o processo de predação de sementes também acaba sendo afetado pelas características da paisagem. A maioria dos estudos em paisagens antrópicas não levam em conta as diferentes escalas em que esse processo opera. Aqui, nós avaliamos como a estrutura da paisagem afeta a predação de sementes de uma palmeira espécie-chave (Syagrus romanzoffiana) em 13 paisagens que variam em cobertura florestal, número e tamanho de fragmentos na Mata Atlântica brasileira. Nós observamos que a predação total de sementes é explicada pelo tamanho, forma e distância até a borda do fragmento. A predação de sementes pelo principal vertebrado predador de sementes (esquilos) também é relacionada com o tamanho e forma dos fragmentos, e eles interagem com os invertebrados de modo que a predação de sementes por estes é explicada principalmente pela predação por esquilos e pela distância até a borda mais próxima. Por sua vês, roedores não arborícolas são mais correlacionados com a quantidade de habitat na paisagem, predando mais sementes em paisagens com menos de 30% de habitat. Nossos resultados indicam que a predação de sementes de Syagrus romanzoffiana é mais afetada por variáveis do fragmento do que por variáveis da paisagem, e que o tamanho, a forma do fragmento e o efeito de borda são melhores preditores da predação de sementes dessa espécie-chave do que a quantidade de habitat na paisagem. Nossos resultados também ressaltam que a geometria do fragmento, uma variável negligenciada na maioria dos estudos, é importante para sistemas ecológicos Seed predation is an important kind of ecological process that affect the abundance, diversity and distribution of plant species. Since this ecological process depends on the presence, abundance and behavior of seed predators, what it is affected by the landscape characteristics, the process of seed predation becomes also affected by the landscape characteristics. Most of studies on seed predation in human-modified landscapes do not take into account the different scales in which this process operates. Here we evaluate how landscape structure affects seed predation in a palm (Syagrus romanzoffiana) that provide a keystone resource to the frugivory community in 13 landscapes that vary in forest cover, fragment number and size in the Brazilian Atlantic forest. We found that the overall seed predation is explained by the fragment size, shape and the distance to the edge. Seed predation by the dominant vertebrate seed predator (squirrels) is also related with the fragment size and shape, and they interact with the invertebrates in such way that the invertebrate seed predation is mainly explained by the squirrel predation and by the distance to the edge. In turn, seed predation by terrestrial rodents is correlated with the habitat amount in the landscape, preying upon more seeds in landscapes with less than 30% of habitat. Our results indicate that the Syagrus romanzoffiana seed predation is more affected by the fragment variables than by landscape ones, and that patch size, shape and edge effect are more important predictors of seed predation of this palm than habitat amount in the landscape. Our results also highlights that the fragment geometry, a neglected variable in most of studies, is importance to ecological systems

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Mendes, Calebe Pereira. "Patch size, shape and edge distance influences seed predation in a keystone palm in tropical rainforests /." Rio Claro, 2014. http://hdl.handle.net/11449/122104.

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Orientador: Mauro Galetti Rodrigues Coorientador: Milton Cezar Ribeiro Banca: Paulo Roberto Guimarães Junior Banca: Marco Aurelio Pizo Ferreira Resumo: A predação de sementes é um importante tipo de processo ecológico, que afeta a abundância, diversidade e distribuição de espécies vegetais. Uma vez que esse processo ecológico depende da presença, abundancia e comportamento dos predadores de sementes, o que é afetado pelas características da paisagem, o processo de predação de sementes também acaba sendo afetado pelas características da paisagem. A maioria dos estudos em paisagens antrópicas não levam em conta as diferentes escalas em que esse processo opera. Aqui, nós avaliamos como a estrutura da paisagem afeta a predação de sementes de uma palmeira espécie-chave (Syagrus romanzoffiana) em 13 paisagens que variam em cobertura florestal, número e tamanho de fragmentos na Mata Atlântica brasileira. Nós observamos que a predação total de sementes é explicada pelo tamanho, forma e distância até a borda do fragmento. A predação de sementes pelo principal vertebrado predador de sementes (esquilos) também é relacionada com o tamanho e forma dos fragmentos, e eles interagem com os invertebrados de modo que a predação de sementes por estes é explicada principalmente pela predação por esquilos e pela distância até a borda mais próxima. Por sua vês, roedores não arborícolas são mais correlacionados com a quantidade de habitat na paisagem, predando mais sementes em paisagens com menos de 30% de habitat. Nossos resultados indicam que a predação de sementes de Syagrus romanzoffiana é mais afetada por variáveis do fragmento do que por variáveis da paisagem, e que o tamanho, a forma do fragmento e o efeito de borda são melhores preditores da predação de sementes dessa espécie-chave do que a quantidade de habitat na paisagem. Nossos resultados também ressaltam que a geometria do fragmento, uma variável negligenciada na maioria dos estudos, é importante para sistemas ecológicos Abstract: Seed predation is an important kind of ecological process that affect the abundance, diversity and distribution of plant species. Since this ecological process depends on the presence, abundance and behavior of seed predators, what it is affected by the landscape characteristics, the process of seed predation becomes also affected by the landscape characteristics. Most of studies on seed predation in human-modified landscapes do not take into account the different scales in which this process operates. Here we evaluate how landscape structure affects seed predation in a palm (Syagrus romanzoffiana) that provide a keystone resource to the frugivory community in 13 landscapes that vary in forest cover, fragment number and size in the Brazilian Atlantic forest. We found that the overall seed predation is explained by the fragment size, shape and the distance to the edge. Seed predation by the dominant vertebrate seed predator (squirrels) is also related with the fragment size and shape, and they interact with the invertebrates in such way that the invertebrate seed predation is mainly explained by the squirrel predation and by the distance to the edge. In turn, seed predation by terrestrial rodents is correlated with the habitat amount in the landscape, preying upon more seeds in landscapes with less than 30% of habitat. Our results indicate that the Syagrus romanzoffiana seed predation is more affected by the fragment variables than by landscape ones, and that patch size, shape and edge effect are more important predictors of seed predation of this palm than habitat amount in the landscape. Our results also highlights that the fragment geometry, a neglected variable in most of studies, is importance to ecological systems Mestre

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Kamnyev, Anna Lynn. "The Role of Patch Size, Isolation, and Forest Condition on Pileated Woodpecker Occupancy in Southwestern Ohio." Wright State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=wright1378227391.

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Kurihara, Yosuke. "Feeding competition in Japanese macaques in Yakushima: effects of intergroup hostility and group size." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225442.

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Lukanik, Irmgard. "An evaluation of movement patterns and effects of habitat patch size on the demography of the Florida mouse (Podomys floridanus)." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002099.

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Mason, Sam. "Within-Flight-Period Dynamics Driven By Phenology And Transect Quality, Not Patch Size Or Isolation, In A Specialist Butterfly, Panoquina Panoquin." W&M ScholarWorks, 2020. https://scholarworks.wm.edu/etd/1593091614.

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As sea levels rise, coastal salt marshes, and the organisms for which they provision, face existential threats. A first step in understanding how projected marsh loss and reconfiguration may impact obligate species is to define their contemporary distribution and temporal shifts in structure using dynamic occupancy models. While occupancy models have commonly been applied to multi-annual butterfly studies, few have investigated population dynamics within a single-season. Here, we used Bayesian dynamic use models to define within-flight-period trends in adult salt-marsh skipper (Panoquina panoquin) use and state change probability. In doing so, we developed and validated a fully-Bayesian test for closure, and documented the ecology, behavior and detectability of this previously unstudied marsh-specialist butterfly. We found evidence that transects in our study system were open to changes in state across the field season, and, consequently, that transect use probability varied considerably by month from 0.35 to 0.84. Latent salt-marsh skipper phenology and transect quality were better predictors of within-flight-period dynamics than marsh area or isolation. This research highlights how variable population dynamics can be within a period of time commonly assumed to be static.

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Sahlsten, Jonas. "Impact of Geographical and Environmental Structures on Habitat Choice, Metapopulation Dynamics and Genetic Structure for Hazel Grouse (Bonasa bonasia)." Doctoral thesis, Uppsala universitet, Institutionen för ekologi och evolution, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7911.

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In this work suitable habitats for hazel grouse (Bonasa bonasia) were identified using ecological niche factor analysis (ENFA). The results from ENFA reveal that hazel grouse utilize a different and more restricted niche than what is generally available in the study area. When a landscape is fragmented the amount of edge increases, which is negative for many species and thus will affect the amount of available area. The perimeter-area ratio was used to analyze the relative importance of geometric shape. In order to estimate a correlation between incidence of hazel grouse and landscape features census data and land cover maps were analyzed with logistic regression models. It is concluded that hazel grouse is tied to coniferous forest and avoid open areas. However, the result indicates that there is a scale effect that should be considered. The amount of edge in a landscape seems to be important and shape of patches could be a better measure in metapopulation dynamics. In this study the Incidence function model was used to estimate occupancy levels and capacity of a landscape to sustain a metapopulation according to four different area measurement scenarios. Results from the simulations indicate that perimeter-area related measures of patch size combined with capacity could be a more important measure for estimation of population dynamics compared to a basic area measurement. Using a landscape genetic approach, hazel grouse genetic structure, neighbourhood size and dispersal distance were estimated. Genetic estimates of dispersal were in concordance with previous ecological estimates. The results indicate evidence of a population structure reminiscent of what has been found in many other Scandinavian animals with a basic north-south divide. No evidence was found that geographic and environmental structures affected gene flow and dispersal patterns for the hazel grouse.

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Kaikkonen, Johanna. "The importance of vegetation type, habitat patch size and isolation for the occurrence of scarce heath butterfly, Coenonympha hero, in the Värmland county." Thesis, Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-6719.

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As agricultural activities in Sweden have ceased nowadays, more and more meadows are being overgrown and planted with forest. Since natural and managed grasslands are very important to a large part of the European butterfly fauna, it is a big threat to these species when meadowlands are being planted and overgrown as it gives them less space and is fragmenting their habitats. The scarce heath butterfly, Coenonympha hero, is one of the butterfly species that is being threatened by this, and has decreased its numbers during the past years. It is protected in Sweden, where it occurs primarily in the Värmland and Dalarna regions. The purpose of this essay is to try to explain how area size, isolation and vegetation will influence populations of scarce heath butterflies in chosen patches in the Värmland province. 55 patches where the butterfly had been observed between the years 2004-2009 were included in this study. The patches were divided into four different categories depending on the vegetation, and the size of each patch along with the distance to the three closest patches was measured. The data was used for statistical analyses in Excel and SAS 9.2. Regression statistics show that there is a significant correlation between the maximum number of butterflies and the size of the patches, and between the closest patch/three closest patches set against the maximum number of butterflies. The type of vegetation seemed to have no specific importance for the butterfly populations according to this study.

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Marcello, Gregory James. "The Effects of Predation and Supplemental Food on Foraging and Abundance of White-Footed Mice (Peromyscus Leucopus) in Relation to Forest Patch Size." Oxford, Ohio : Miami University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1123179821.

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Yager, Lisa Y. "Watching the grass grow effects of habitat type, patch size, and land use on cogongrass (Imperata cylindrica (L.) Beauv.) spread on Camp Shelby Training Site, Mississippi /." Diss., Mississippi State : Mississippi State University, 2007. http://sun.library.msstate.edu/ETD-db/ETD-browse/browse.

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Christensen, Pernilla. "The long-term decline of the grey-sided vole (Clethrionomys rufocanus) in boreal Sweden: importance of focal forest patch and matrix." Doctoral thesis, Umeå : Department of Ecology and Environmental Science, Umeå Univ, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-876.

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Alqawasmeh, Yousef. "Models for Persistence and Spread of Structured Populations in Patchy Landscapes." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36845.

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In this dissertation, we are interested in the dynamics of spatially distributed populations. In particular, we focus on persistence conditions and minimal traveling periodic wave speeds for stage-structured populations in heterogeneous landscapes. The model includes structured populations of two age groups, juveniles and adults, in patchy landscapes. First, we present a stage-structured population model, where we divide the population into pre-reproductive and reproductive stages. We assume that all parameters of the two age groups are piecewise constant functions in space. We derive explicit formulas for population persistence in a single-patch landscape and in heterogeneous habitats. We find the critical size of a single patch surrounded by a non-lethal matrix habitat. We derive the dispersion relation for the juveniles-adults model in homogeneous and heterogeneous landscapes. We illustrate our results by comparing the structured population model with an appropriately scaled unstructured model. We find that a long pre-reproductive state typically increases habitat requirements for persistence and decreases spatial spread rates, but we also identify scenarios in which a population with intermediate maturation rate spreads fastest. We apply sensitivity and elasticity formulas to the critical size of a single-patch landscape and to the minimal traveling wave speed in a homogeneous landscape. Secondly, we use asymptotic techniques to find an explicit formula for the traveling periodic wave speed and to calculate the spread rates for structured populations in heterogeneous landscapes. We illustrate the power of the homogenization method by comparing the dispersion relation and the resulting minimal wave speeds for the approximation and the exact expression. We find an excellent agreement between the fully heterogeneous speed and the homogenized speed, even though the landscape period is on the same order as the diffusion coefficients and not as small as the formal derivation requires. We also generalize this work to the case of structured populations of n age groups. Lastly, we use a finite difference method to explore the numerical solutions for the juveniles-adults model. We compare numerical solutions to analytic solutions and explore population dynamics in non-linear models, where the numerical solution for the time-dependent problem converges to a steady state. We apply our theory to study various aspects of marine protected areas (MPAs). We develop a model of two age groups, juveniles and adults, in which only adults can be harvested and only outside MPAs, and recruitment is density dependent and local inside MPAs and fishing grounds. We include diffusion coefficients in density matching conditions at interfaces between MPAs and fishing grounds, and examine the effect of fish mobility and bias movement on yield and fish abundance. We find that when the bias towards MPAs is strong or the difference in diffusion coefficients is large enough, the relative density of adults inside versus outside MPAs increases with adult mobility. This observation agrees with findings from empirical studies.

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Müller, Thomas. "Untersuchung des Zusammenhangs zwischen der Landschaftsstruktur und dem Vorkommen dreier Vogelarten." Bachelor's thesis, Hochschule für Technik und Wirtschaft Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:520-qucosa-211816.

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In dieser Arbeit wurde der Frage nachgegangen, inwieweit sich die Habitatansprüche von drei Brutvogelarten, der Offenlandart Feldlerche (Alauda arvensis), der Heckenart Neuntöter (Lanius collurio) und der Waldart Schwarzspecht (Dryocopus martius), mit Landschaftsstrukturmaßen darstellen lassen, und ob sich Landschaftsstrukturmaße für die Habitatmodellierung eignen. Basis für die Berechnung der Landschaftsstrukturmaße ist ein Flächenschema des IÖR-Monitors aus dem Jahr 2013, welches aus Daten des AFIS-ALKIS-ATKIS-Modells (AAA-Modells) aufgebaut wurde. Dieses Schema bietet redundanzfreie Flächennutzungsdaten für ganz Deutschland. Da es nur flächenhafte Elemente enthielt, wurde es um gepufferte linienhafte Elemente, genauer um Hecken, Baumreihen und Feldwege ergänzt. Die Artdaten stammen aus dem Monitoring häufiger Brutvögel (MhB), ebenfalls aus dem Jahr 2013. Die Berechnungen der Landschaftsstrukturmaße wurden mittels ArcGIS-Modellen durchgeführt. Für die Feldlerche und den Schwarzspecht wurden die Landschaftsstrukturmaße Mean Shape Index (MSI), Mean Patch Size (MPS), Anteil geeigneter Habitate (Percentage of Landscape, PLand), Total Core Area (TCA), Fläche geeigneter Biotope ohne anthropogene Störeinflüsse (Fl_ungest) und die Kantendichte der Landschaft (Edge Density, ED) berechnet. Für den Neuntöter sind es MSI, MPS, PLand, Fl_ungest, die Kantendichte und die Fläche geeigneter Gehölzbiotope und Hecken. Es wurde aufgezeigt, dass teilweise höchst signifikante lineare Zusammenhänge zwischen dem Vorkommen der drei Arten und den Landschaftsstrukturmaßen existieren. Die damit erklärten Streuungen der Brutpaarzahlen sind allerdings relativ gering. Das Bestimmtheitsmaß B oder R² der Regressionsgeraden beträgt für die Feldlerche maximal 0,285 bei der Fläche ungestörter Habitate, für den Schwarzspecht maximal 0,332 bei dem Anteil geeigneter Habitate und beim Neuntöter lediglich 0,038, ebenfalls für die Fläche ungestörter Habitate. Der Grund hierfür ist, dass die Arten Ansprüche an die Habitate stellen, die sich nicht mit Landschaftsstrukturmaßen erklären lassen. Die Modelle der multiplen linearen Regression sind ungeeignet, um Brutpaarzahlen der Arten vorherzusagen. Ohnehin war es nur für die Feldlerche möglich, ein solches Modell zu erstellen, das höhere Bestimmtheitsmaße aufweist als die einzelnen Landschaftsstrukturmaße. Deutlich bessere Ergebnisse wurden mit einem Modell erzielt, das die Eignung der Landschaft und ihrer Struktur als Habitat anhand einer Bewertungsmatrix beurteilt. Hier wurde bestimmt, wie hoch der Anteil besetzter Untersuchungsflächen an der Gesamtzahl von Untersuchungsflächen einer bestimmten Gesamtpunktzahl ist. Die Zusammenhänge zwischen Punktzahl und Anteil besetzter Flächen wurde mit teils nichtlinearen Regressionsfunktionen dargestellt. Der Anteil erklärter Abweichungen (R²) beträgt bei der Funktion der Feldlerche 97,1%, der des Schwarzspechts 88,5% und der des Neuntö-ters 49,3%.

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Staffan, Paul. "Design of an ultra-wideband microstrip antenna array with low size, weight and power." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1578437280799995.

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Cunningham, Russell Andrew. "EFFECTS OF REGENERATION OPENING SIZE AND SIMULATED CROP TREE RELEASE ON VOLUME YIELDS AND ECONOMIC VALUE IN OAK-DOMINATED STANDS." UKnowledge, 2014. http://uknowledge.uky.edu/forestry_etds/19.

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Patch clearcutting can be put to effective use for landowners with relatively small stands of timber. This project was designed to determine how clearcut opening size and mid-rotation crop tree release affects the value and volume of sawtimber at the end of rotation. In 1960 patch clearcuts were established in three different diameters, 50ft (.05ac), 150ft (.41ac), and 250ft (1.13ac). Current stand data (2011) was collected to determine trees per acre, basal area, average tree diameter, volume, and value. These data were input into a growth simulator to determine future trees per acre, basal area, average tree diameter, volume, and value with a crop tree release treatment and a control to 2061. The 50ft openings yielded little merchantable volume at mid-rotation and were primarily composed by shade tolerant species. In the 150ft and 250ft openings, there was better species diversity and an increase in sawtimber volume and value. Using openings of 150ft or greater, landowners can regenerate commercially important species and manage their forests to produce valued timber and maintain aesthetics.

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Kuo, Shan-Yu, and 郭珊妤. "Adaptive Texture synthesis Based on Maximum Patch Size." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/70944138700493155768.

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碩士 義守大學 資訊工程學系碩士班 99 The developments of 3D virtual reality are becoming increasingly attractive in recent years. In practical applications, the scene of 3D virtual reality should be similar to the realistic view. If the resolution of the original image is too low, the use of resizing technique could cause image distortion. In general, high visual quality needs effect sufficient image resolution. In order to solve this problem, various texture synthesis algorithms have been proposed. However, the existing techniques suffer on computational cost and image quality. This thesis aims at how to synthesis a large-sized target image from a small-sized input. Theoretically, an ideal output could preserve the structure and continuity of the original image. Experimental results indicate that the use of full source image achieves to preserve texture structures of the source images. In addition, we propose an image pre-extended method that provides more choices of sampling for texture synthesis.

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Chu, Yu-Yu, and 朱育頤. "Study on Choosing Better Patch Size for Texture Synthesis." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/22081188427602538718.

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碩士 國立臺北教育大學 資訊科學系碩士班 95 As development of computer technique, multimedia application is very general. One of techniques is Texture Synthesis which is adopted by image process and 3-dimension animation. The purpose of this algorithm is to generate a customized-size image by input image. The output image is similar in visual and textural. Patch size is extremely important in patch-based texture synthesis algorithm. When it is too small, output image textural size maybe be out of accord with input. However, patch size is too big, output image maybe be smashed. For this consideration, our paper present a algorithm that is choosing better patch size and improve image quality by this result, our experiment is cooperated to the Image Quilting algorithm[9] . According to our algorithm, experiment results have better outcome aiming at structural image.

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Chen, Bor-Tsong, and 陳柏璁. "REFLECTARRAY USING VARIABLE SIZE PATCH WITH SLOT IN A TWO-LAYER SUBSTRATE." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/61736027341739434205.

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碩士 大同大學 通訊工程研究所 93 This thesis demonstrates a new configuration of reflectarray using variable size patch with slot (RVSPS) as the construction element. This configuration improves phase curve of the reflectarray using variable size patch (RVSP) in FR4 material. RVSPS has a more lineaer phase curve in comparison with that of the RVSP. Experimental results of RVSPS showed that the maximum gain is 24.45dB at 11.4GHz. It has a 1.5-dB gain bandwidth of 19.3%. The aperture efficiency is 31.48% and the cross-polarization level is bellow around 25dB.

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蕭賀臻. "The effect of the board size on the characteristic of patch antenna." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/91363232645632831901.

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碩士 長庚大學 電子工程研究所 92 This paper investigates the effect of finite substrate sizes on the performance of microstrip antennas. First, IE3D is used to simulate a patch antenna resonant at 5 GHz . Then HFSS is used to simulate the effects of the board sizes on the characteristics of the patch antenna. Finally, the simulated and measured results are compared. It is hoped that how the characteristics of the patch antenna, such as resonant frequencies, S11 and antenna gains change with different substrate sizes can be found in this research. This result can help reducing errors when designing microstrip antennas in the future.

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Hsieh, Yi-Hang, and 謝易翰. "Effects of patch Size on the Growth of the Hard Clam, Meretrix Lusoria." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/59819802265314376108.

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碩士 國立中山大學 海洋生物學系 85 The hard clams Meretrix lusoria were cultured at a high local density of 1600 claims/m2 in four patch areas: 0.2, 1.8, 5.0, and 9.8 m2 in one pool from April to September in 1995, to compare the effect of patch size on the growth of M. lusoria. The growth rate of the clams decreased when patch size increased, and the individuals located at the centers of patches exhibited reduced growth relative to those on the edges of patches. The ratio of shell length to shell height in large patches was smaller than that in small patches. Data of this experiment suggested that M. lusoria, a suspension-feeder, may grow well and show less or no effect of competition at high local density in small patches, but the infra-specific competition caused by high density decrease the growth of clams when patches are large enough.

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Johnson, Cheryl Ann. "The effect of patch size and competitor number on aggression among foraging house sparrows." Thesis, 2001. http://spectrum.library.concordia.ca/1625/1/MQ90370.pdf.

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To test between the contradictory predictions of resource defence theory and a modified hawk-dove model, I examined the effect of patch size and competitor number on aggression among foraging house sparrows, Passer domesticus . The birds were observed at feeding tables of seven different sizes, each table doubling in surface area from 0.014 m 2 to 0.922 m 2 , allowing for a broader quantitative description of changes in aggression with patch size than previously examined. Resource defence theory predicts that small patches will be more defendable than large patches and that aggression will peak at intermediate competitor numbers at defendable patches. In contrast, a modified hawk-dove model predicts an increase in aggressiveness with competitor number; the model makes no predictions about patch size. Contrary to resource defence theory, birds did not defend an entire patch, even when it was as small as 0.014 m 2 . As a result, aggression among the birds decreased more gradually with increasing patch size than expected by an all-or-none threshold model of resource defence. Moreover, birds fought more frequently and intensely at high competitor numbers, a result that is more consistent with the predictions of a modified hawk-dove model than the dome-shaped relationship predicted by models of resource defence. Interestingly, females were more aggressive and foraged faster than males. Because females were able to compete more effectively when individuals were aggressive, the proportion of females increased as patch size decreased. My results have implications for the truncated phenotype ideal free distributions.

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Bishop, Joseph A. "Temporal dynamics of forest patch size distribution and fragmentation of habitat types in Pennsylvania." 2008. http://www.etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-2543/index.html.

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Beltman, Douglas J. "The effects of forest patch size on bird distribution in a forest mosaic landscape." 1990. http://catalog.hathitrust.org/api/volumes/oclc/22599073.html.

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Thesis (M.S.)--University of Wisconsin--Madison, 1990. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 29-33).

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Cole, Victoria J., Linda G. Johnson, and Christopher D. McQuaid. "Effects of patch-size on populations of intertidal limpets, Siphonaria spp., in a linear landscape." 2012. http://hdl.handle.net/10962/d1011050.

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Organisms with different life-histories and abilities to disperse often utilise habitat patches in different ways. We investigated the influence of the size of patches of rock (separated by stretches of sand) on the density of pulmonate limpets (Siphonaria spp.) along 1500 km of the linear landscape of the South African coastline. We compared the influence of patch-size on two congeneric species with different modes of development, S. serrata a direct developer, and S. concinna a planktonic developer. We tested the spatial and temporal consistency of the effects of patch-size by sampling 7 independent regions spanning the distributional range of both species of limpets, and by sampling one region at monthly intervals for 1 year. Within each region or month, 4 small patches (<20 m in length) interspersed with the 4 large patches (>60 m in length) were sampled. Across the entire geographic range and throughout the year, there were more of both species of limpets in large patches than in small patches. In most regions, there was greater variability in large patches than small patches. Variability within patches in a single region was similar throughout the year, with greater variability of both species in large than in small patches. We found little influence of the mode of development on the response of limpets to patch-size. Our findings highlight the importance of understanding patterns of distribution of species with respect to habitat heterogeneity in linear landscapes, and contradict the idea that organism mobility at an early ontogenetic stage directly affects habitat use.

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Nelson, Natasha. "The effects of patch size and isolation on juvenile emigration in gray-tailed voles, Microtus canicaudus." Thesis, 1996. http://hdl.handle.net/1957/33978.

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Ferenc, Michal. "Bird communities in urban green space: Effects of habitat patch size, vegetation structure and urbanization gradient." Master's thesis, 2009. http://www.nusl.cz/ntk/nusl-279436.

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Kim, Jae-woo. "The effects of patch shape and group size on economic defendability and growth depensation in juvenile convict cichlids." Thesis, 2005. http://spectrum.library.concordia.ca/8289/1/MR04341.pdf.

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While the effect of patch area on economic defendability has attracted considerable attention, there has been little research on patch shape. In addition, few studies have investigated the effects of resource defense from the perspectives of both defenders and intruders. Hence, I manipulated food patch shape independent of patch area (square, 13.6 x 13.6 cm; rectangular, 46.5 x 4.0 cm; elongated, 93.0 x 2.0 cm) and group size (three, six, twelve fish) in a 3 X 3 factorial design. I tested the predictions that the frequency of aggression, degree of resource monopolization and size variation within groups would decrease as patch perimeter and group size increased. As predicted, with increasing patch perimeter the frequency of aggression and the degree of resource monopolization decreased, but there was no change on growth depensation (size variability). Increasing the number of fish decreased the frequency of aggression, degree of resource monopolization, leading to less size variation within groups. My study is one of the first factorial studies to manipulate the actual perimeter of the food patch to show that increasing the patch perimeter had the same effect as increasing group size on the economic defendability of a patch. My study also demonstrated that it is important to the theory of resource defense to examine the foraging success of both the defenders and intruders.

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McDonald, Laurel. "The influence of patch size, landscape composition, and edge proximity on songbird densities and species richness in the northern tall-grass prairie." 2017. http://hdl.handle.net/1993/32092.

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Area sensitivity of North American grassland birds is a significant conservation concern; yet, its causes are not known. I used point count data from 20 tall-grass prairie patches in Southern Manitoba to assess the relative importance of patch size, edge proximity, and landscape composition on the densities and species richness of grassland songbirds. The degree to which the landscape surrounding point count plots was open, as opposed to forested or urban, had a positive effect on species richness and the densities of most focal species, and was more important than patch size, edge proximity, or habitat amount. These results suggest that landscape openness, not patch size (with which it is usually correlated) drives area sensitivity. Small grassland patches embedded in open landscapes are less susceptible to area sensitivity and may be of high conservation value for grassland birds. February 2017

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Robinson, Dianne Hali. "Effects of Habitat Characteristics on Occupancy and Productivity of a Forest-Dependent Songbird in an Urban Landscape." Thesis, 2013. http://hdl.handle.net/1969.1/149511.

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Habitat fragmentation and isolation can result in decreased occupancy and reproductive success within songbirds, particularly for species inhabiting urban environments where suitable habitat may be limited. The golden-cheeked warbler (Setophaga chrysoparia) is a federally endangered songbird that inhabits oak-juniper (Quercus spp.- Juniperus spp.) across central Texas. Past research on this warbler has indicated decreased patch occupancy near urban areas and negative reproductive effects associated with decreased distance to edge and decreased canopy cover. A rural study indicated warblers occupy patches ≥3 ha, and warblers in patches ≥20 ha are more likely to successfully fledge young. There are no thresholds yet identified for this warbler within urban environments, where effects of habitat fragmentation on reproductive success are more pronounced than within rural environments. I monitored patch occupancy, territory establishment, pairing success, and fledging success of warblers in an urban environment. I determined minimum patch-size thresholds for productivity measurements, and also monitored effects on productivity from canopy cover, woodland composition, distance to and size of the nearest habitat patch, and distance to the nearest habitat patch >100 ha. I compared my results to those from a similar study conducted in a rural system. I compared territory size and territory density between an urban and rural system. Warblers occupied 24% (n = 63) patches surveyed; the smallest patch occupied was 3.5 ha. The smallest patch with an established territory was 10.7 ha, and 10% (n = 63) of habitat patches had at least one established territory. Warblers successfully fledged young in 3 patches, the smallest of which was 26.5 ha. I found patch-size was predictive for territory establishment and pairing success with warblers requiring 13 ha (95% CI: 10.0 – 16.8 ha) and 19 ha (95% CI: 15.7 – 22.6 ha) habitat patches, respectively. I found a minimum threshold of approximately 66% canopy cover (95% CI: 65.2 – 66.4%) required for patch occupancy, and found no warblers established a territory in a habitat patch >25 m from the next nearest patch. I found higher minimum thresholds within an urban system for territory establishment and pairing success than those seen within a rural system. I suggest preserving warbler habitat patches >22 ha that are in close proximity to other habitat patches. This will help to enhance warbler habitat within urban areas and maintain reproductively viable habitat patches, while not halting development completely.

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Máslo, Petr. "Faktory ovlivňující složení hmyzích společenstev na malých mršinách." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-348344.

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This thesis describes invertebrate community on cadavers of small mammals, in particulat how cadaver size influences abundace, density, species richness and composition of the necrobiont community. Cadaver size preference of present insects is also described. Field experiments were performed in 2014 in meadow habitats in spring, summer and autumn season. Cadavers were chosen in three weight groups: mice (20 g), small rats (100 g) and large rats (400 - 500 g). Invertebrate abundance increases with cadaver mass, density of the community remains constant. Larger cadavers also have higher species richness. Most dominant ecological guild are necrophages, represented mosty by blow flies (Calliphoridae). Cadaver size preference of recorded insects differ, necrophagous and predatory taxa tend to prefer larger cadavers. Omnivorous carrion beetles (Silphidae: Nicrophorus) prefer small cadavers. Sex of the carrion beetles (Silphidae) does not affect their cadaver size preference, males and females of particular species have very similar preferences. Keywords Ephemeral resource patch, cadaver, necrobiont, size, abundace, diversity, competition, insect communities

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Müller, Thomas. "Untersuchung des Zusammenhangs zwischen der Landschaftsstruktur und dem Vorkommen dreier Vogelarten: eine GIS-gestützte Überprüfung der Ansprüche der Feldlerche Alauda arvensis, des Neuntöters Lanius collurio und des Schwarzspechts Dryocopus martius an die Landschaft." Bachelor's thesis, 2015. https://htw-dresden.qucosa.de/id/qucosa%3A23303.

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Silva, Lourenço de Mértola Belford Correia da. "Quality assessment of 2D image rendering for 4D light field content." Master's thesis, 2018. http://hdl.handle.net/10071/18244.

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Light Field (LF) technology, comprising visual data representations with huge amount of information, can be used to solve some of the current 3D technology limitations while enabling also new image functionalities not straightforwardly supported by traditional 2D imaging. However, current displays are not ready to process this kind of content, which means that rendering algorithms are necessary to present this type of visual content in 2D or 3D multi-view displays. However, the visual quality experienced by the user is highly dependent on the rendering approach adopted. Therefore, LF rendering technology requires appropriate quality assessment tests with real people, as there is no better and reliable way to assess the quality of these type of algorithms. In this context, this dissertation aims to study, implement, improve and compare various LF rendering algorithms and rendering approaches. Performance evaluation is done through subjective quality assessment tests aiming to understand which algorithm performs better in certain situations and the subjective quality impact of some of those algorithm parameters. Additionally, a comparison of single plane of focus versus all-infocus LF rendering approaches is also evaluated. A tecnologia de campos de luz – Light Field (LF), composta por representações visuais de dados com grande quantidade de informação, pode ser usada para solucionar algumas das limitações atuais da tecnologia 3D, além de permitir novas funcionalidades que não são suportadas diretamente pela imagem 2D tradicional. No entanto, os dispositivos de visualização actuais não estão preparados para processar este tipo de conteúdo, o que significa que são necessários algoritmos de renderização para apresentar este tipo de conteúdo visual em versão 2D ou em versão 3D com múltiplas vistas. No entanto, a qualidade visual do ponto vista da percepção do utilizador é altamente dependente da abordagem de renderização adotada. Portanto, a tecnologia de renderização LF requer avaliação de qualidade adequada com pessoas reais, já que não há maneira melhor e mais confiável de avaliar a qualidade deste tipo de algoritmos. Neste contexto, esta dissertação tem como objetivo estudar, implementar e comparar diversos algoritmos e abordagens de renderização LF. A avaliação de desempenho é feita recorrendo a testes subjetivos de avaliação de qualidade para entender qual algoritmo que apresenta melhor desempenho em determinadas situações e a influência, em termos da qualidade subjetiva, de alguns parâmetros de input em certos algoritmos. Além disso, também é avaliada uma comparação de abordagens de renderização com focagem em apenas um plano versus renderização com focagem em todos os planos.

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