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Full-Text Articles in Environmental Sciences
Using Landscape Pattern Metrics To Characterize Ecoregions, Martha Isabel Posada Posada
Using Landscape Pattern Metrics To Characterize Ecoregions, Martha Isabel Posada Posada
School of Natural Resources: Dissertations, Theses, and Student Research
Ecological regions, or ecoregions, are areas that exhibit “relative homogeneity in ecosystems”. The principal objective of this research was to determine if and how landscape structure (quantified by landscape pattern metrics) may be related to ecoregions defined using Omernik’s approach to ecoregionalization. Nine key landscape pattern metrics (number or LULC classes and the proportion of each class, number of patches, mean patch size and area-weighted fractal dimension, perimeter-area fractal dimension, contagion, mean Euclidean nearest neighbor distance and interspersion and juxtaposition index) where used to asses landscape structure in a sample of 26 Omernik Level III ecoregions located in the central …
Review Of Conspecific Attraction And Area Sensitivity Of Grassland Birds, David R.W. Bruinsma, Nicola Koper
Review Of Conspecific Attraction And Area Sensitivity Of Grassland Birds, David R.W. Bruinsma, Nicola Koper
Great Plains Research: A Journal of Natural and Social Sciences
Many species of grassland birds are area sensitive, which may exacerbate the ecological effects of the extensive loss and fragmentation of grasslands that has taken place across the northern Great Plains. However, the reasons for this area sensitivity are unclear, as vegetation structure, matrix composition, and restriction of movements among patches do not seem to provide viable explanations for species native to grasslands. Con specific attraction, whereby species are behaviorally stimulated to select habitat or establish territories near individuals of the same species, may help explain this area sensitivity. We review and discuss theoretical and empirical research on avian conspecific …
Spatial Complexity In Fragmenting Amazonian Rainforests: Do Feedbacks From Edge Effects Push Forests Towards An Ecological Threshold?, Graeme S. Cumming, Jane Southworth, Xanic J. Rondon, Matthew Marsik
Spatial Complexity In Fragmenting Amazonian Rainforests: Do Feedbacks From Edge Effects Push Forests Towards An Ecological Threshold?, Graeme S. Cumming, Jane Southworth, Xanic J. Rondon, Matthew Marsik
United States Department of Commerce: Staff Publications
Deforestation and resulting landscape fragmentation are important concerns in many tropical areas. Deforestation is a complex process with many potential feedback loops, many of which are ignored in models that attempt to interpolate forest loss based on past deforestation rates. In addition, most ecological studies of the impacts of deforestation have focused on landscapes that are already fragmented. These studies ignore the fact that edge effects, such as anthropogenic fire, reach their maximum well before habitat connectivity is lost and may create positive feedbacks that result in further fragmentation. We developed a simple model to explore the potential influence of …