Reason for Selection
Resilience scores quantify a combination of landscape diversity and local connectedness, stratified by geophysical setting and ecoregion. These measures represent the the diversity of microclimates available to species based on their topography, wetland density, and elevation range, as well as the connectivity of natural cover. This builds on research from Anderson and Ferree (2010), who showed geophysical diversity and elevation range were associated with biodiversity in the Eastern United States. This resilience analysis identifies areas where diverse species are likely to be able to move and adapt to changing conditions. Learn more at:
http://nature.org/TNCResilience.
Input Data
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The Nature Conservancy’s (TNC) Resilient Land dataset (Anderson et. al. 2016)
Mapping Steps
Landscape diversity ranked sites using the variety of landforms, elevation range, and wetland density (for very flat areas). Local connectedness measured natural land cover types within a 3 km radius of each cell.
1) We used TNC's Resilience Stratified by Setting and Ecoregion with Regional Override data
2) To target specific areas for conservation, we reclassified the original continuous data layer into the seven standard deviation-based classes that TNC uses in display of the data.
3) We used the coastal zone data layer provided by TNC to remove areas in the 0-3 ft elevation zone not well captured by this dataset. These areas were changed to NoData.
4) We converted the data from the orignal 30 m pixels to 200 m pixels using majority resample.
Indicator values were assigned as follows:
0 = Developed (low)
1 = Final Resilience Score: Far below average (<-2 SD)
2 = Final Resilience Score: Below average (-1 to -2 SD)
3 = Final Resilience Score: Slightly below average (-0.5 to -1 SD)
4 = Final Resilience Score: Average (0.5 to -0.5 SD)
5 = Final Resilience Score: Slightly above average (0.5 to 1 SD)
6 = Final Resilience Score: Above average (1 to 2 SD)
7 = Final Resilience Score: Far above average (>2 SD) (high)
Defining the Spatial Extent of Ecosystems
Landscape and waterscape indicators were defined as features that applied across all terrestrial and aquatic ecosystems and no refined extent was needed.
Known Issues
-- Does not explicitly account for threats from sea-level rise; therefore, following the recommendation of the data developers, we removed areas in the 0-3 ft elevation zone.
-- Does not account for the occurrence and timing of natural disturbance processes, particularly fire. Without fire, resilient sites in many ecosystems will not serve as biodiversity hotspots. This is particularly problematic in the pine and prairie ecosystem and the shortleaf pine/Piedmont prairie component of the upland hardwood ecosystem.
Disclaimer: Comparing with Older Indicator Versions
While this indicator has changed since the version of resilient biodiversity hotspots used in Blueprint 2.0 and the version of resilient biodiversity hotspots used in Blueprint 2.1, this only reflects differences in the way it was calculated and should not be compared to measure change over time.
Indicator Overview
The South Atlantic ecosystem indicators serve as the South Atlantic LCC's metrics of success and drive the identification of priority areas for shared action in the Conservation Blueprint. To learn more about the indicators and how they are being used, please visit the indicator page. Check out the Blueprint page for more information on the development of the Blueprint, a living spatial plan to conserve our natural and cultural resources.
Literature Cited
Anderson, M.G., A. Barnett, M. Clark, C. Ferree, A. Olivero Sheldon, J. Prince. 2016. Resilient Sites for Terrestrial Conservation in Eastern North America. The Nature Conservancy, Eastern Conservation Science.
Anderson, M.G., Ferree, C.E., 2010. Conserving the stage: climate change and the geophysical underpinnings of species diversity. PLoS One 5, e11554.
