OOS 17-2
Representation of ecological systems within the National Wilderness Preservation System of the contiguous United States: Prioritizing conservation areas for the next 50 years
The National Wilderness Preservation System (NWPS) is a collection of lands designated by Congress as ‘wilderness areas’—“where the earth and its community are untrammeled by man.” Wilderness areas are increasingly recognized for their importance in providing critical species’ habitats. Conservation of biological diversity will likely be most effectively accomplished through a network of connected wilderness areas that represent the full expression of nature’s diverse ecosystems. Additionally, wilderness areas will better serve as scientific controls by which to assess the impacts of climate change if they capture the full range of ecosystem diversity. Thus, it is important to evaluate how well the NWPS represents the biological diversity of America’s public wildlands, including gaps in regional or local representation of ecosystem diversity. We used national land cover data to calculate the ecological representation of lands in the NWPS at various scales: nationally, by several EPA ecoregional levels, by state, and within several National Forests and Congressional districts. We also describe a process for prioritizing areas to add to the NWPS to increase land cover class representation at the relevant scales for administrative and legislative action.
Results/Conclusions
As of January 2014, the NWPS contained 757 wilderness areas in 44 states totaling 44,317,920 hectares, or nearly 5% of all land in the United States (about half of which occurs in Alaska). Of the 576 total ecological systems represented in the national land cover data for the contiguous US (CONUS), 431 of these (75%) occurred within wilderness boundaries. These ecological systems occurring in wilderness are not evenly distributed within regions or across the CONUS. Some systems are only represented by a few hectares within wilderness, and the majority of area within wilderness occurs in western regions. The NWPS thus represents poorly some ecological systems at the national scale (all public and private lands), within the system of federal public lands, and within the federal public lands that are still largely in their natural condition and are immediately eligible for wilderness designation (i.e., “roadless” areas). We will discuss these gaps from national to local scales and provide insights into the need to expand the NWPS to new areas so that wilderness areas will better protect ecological diversity in the face of climate change, as well as continue to serve as “controls” for ecological science.