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Desert grasslands, which are very sensitive to external drivers like climate change, are areas affected by rapid land degradation processes. In many regions of the world the common form of land degradation involves the rapid encroachment of woody plants into desert grasslands. This process, thought to be irreversible and sustained by biophysical feedbacks of global desertification, results in the heterogeneous distribution of vegetation and soil resources. Most of these shrub-grass transition systems at the desert margins are prone to disturbances such as fires, which affect the interactions between ecological, hydrological, and land surface processes. Here we investigate the effect of prescribed fires on the landscape...
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The loss of coastal marshes is a topic of great concern, because these habitats provide tangible ecosystem services and are at risk from sea-level rise and human activities. In recent years, significant effort has gone into understanding and modeling the relationships between the biological and physical factors that contribute to marsh stability. Simulation-based process models suggest that marsh stability is the product of a complex feedback between sediment supply, flooding regime and vegetation response, resulting in elevation gains sufficient to match the combination of relative sea-level rise and losses from erosion. However, there have been few direct, empirical tests of these models, because long-term datasets...
Categories: Publication; Types: Citation; Tags: Ecosystems
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We investigated the effects on the reservoir food web of a new temperature control device (TCD) on the dam at Shasta Lake, California. We followed a linked modeling approach that used a specialized reservoir water quality model to forecast operation-induced changes in phytoplankton production. A food web–energy transfer model was also applied to propagate predicted changes in phytoplankton up through the food web to the predators and sport fishes of interest. The food web–energy transfer model employed a 10% trophic transfer efficiency through a food web that was mapped using carbon and nitrogen stable isotope analysis. Stable isotope analysis provided an efficient and comprehensive means of estimating the structure...
Categories: Publication; Types: Citation; Tags: Ecosystems
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This dataset shows innundation from the terrestrial ecosystems (reference classification) of South America, Central America, and Mexico. South America: This dataset represents Ecological System patches using various reference datasets. Original data generarated from 2000 era data, modeled in 2005 and updated in 2008 and 2010.Originally, this project developed a GIS modeling approach, using a variety of abiotic and biotic data sets, to produce a map of the distribution of Latin America and Caribbean (LAC) ecological systems throughout South America for use in ecoregional assessments. Ecological systems, defined as spatially co-occuring assemblages of vegetation types sharing a common underlying substrate, ecological...
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This dataset was extracted from the terrestrial ecosystems of South America dataset. South America: This dataset represents Ecological System patches using various reference datasets. Original data generarated from 2000 era data, modeled in 2005 and updated in 2008 and 2010.Originally, this project developed a GIS modeling approach, using a variety of abiotic and biotic data sets, to produce a map of the distribution of Latin America and Caribbean (LAC) ecological systems throughout South America for use in ecoregional assessments. Ecological systems, defined as spatially co-occuring assemblages of vegetation types sharing a common underlying substrate, ecological process, or gradient, were identified for all...


map background search result map search result map Terrestrial Ecosystems of Latin America: Innundation (Level 3) Terrestrial Ecosystems (Reference Classification) of Chile Terrestrial Ecosystems (Reference Classification) of Chile Terrestrial Ecosystems of Latin America: Innundation (Level 3)