NLCD began as a land-cover mapping program, and produced national land cover maps for 1992 and 2001. With the 2006 update it is transitioning to a land-cover monitoring program. more...

Land Cover Trends is a national project that describes for specific geographic areas within the conterminous United States the rates, causes, and consequences of land use and land cover change for the period 1972 to 2000. more...

As a part of the wildfire and debris flow hazards assessment for the Southern California MHDP, this research will characterize the impact of past management activities on loss of native plant communities and replacement by alien-invasive vegetation. We are using satellite data to regionally map occurrences of alien-invasive grasses and forbs in the chaparral communities of Southern California. MODIS satellite data coupled with field data was used to extract and characterize the phenological signatures of landscapes dominated by alien-invasive annuals (grasses and forbs) as well as landscapes dominated by native chaparral vegetation. Based on the distinctive phenologies of the two vegetation types, a suite of Landsat images was identified to discriminate between the invasive annuals and model their current regional distribution. Indices of annual vegetation derived from these Landsat data are being developed and historical Landsat data processed to extrapolate these results both temporally and spatially to compile a record of vegetation-conversion change across the southern California region back to the 1970’s. more...

Changing land use has an important impact on surface characteristics that subsequently affect land/atmosphere interactions (e.g., albedo, water, carbon). The timing of interactions may also change as land cover changes: e.g., a forest replaced by agricultural will have significantly shorter growing season. This project will develop methodologies for summarizing phenological impacts of land cover change by coupling satellite phenology with detailed land cover change information. "more...

It is critical that science-based management plans be developed to provide sustainable populations of wild sheep and goats. Several Asian Argali’s are listed as threatened or endangered, requiring long-term effective management. Wild sheep in particular are sensitive to change and very well could be considered an indicator species regarding the effects of climate change in arctic and high mountain ecosystems. more...

The research proposed here will characterize the seasonal phenology and interannual dynamics of ecological systems as recently mapped in the arid and semi-arid southwest to create a 'phenological profile' of the system. Changes in these profiles may be due to many factors, including fire, invasion of non-native species, land use activities, and vegetation response to climate fluctuations or change. In this time of apparent global change, it is important to recognize and monitor even subtle landscape changes, and necessary to separate trends toward a new state of the ecological system from patterns of normal variability. This research will help identify these trends as early as possible. more...

The Lower Colorado River is being mapped from a historical perspective and made available to scientists studying vegetation communities, wildlife, surface water, soil moisture, energy processes, water quantity, and sediment loads via a web-mapping service. The U.S. Bureau of Reclamation (BOR), Resources Management Office located in Boulder City, Nevada is partnering with USGS on this project. more...

Lake Tahoe is a natural resource famous for its alpine setting and deep, clear waters. more...