Modeling landscape ecological integrity to support mitigation planning for renewable energy development
Landscape assessments to evaluate the status and trends of natural resources have been the focus of landscape planners for several years. The application of these landscape assessments is expected to increase on the basis of recent US Department of the Interior Secretarial Orders emphasizing landscape-scale approaches to identify and facilitate mitigation and conservation priorities. Many of these landscape planning efforts rely on geospatial models that characterize the ecological integrity of the landscape. These general models utilize measures of habitat disturbance and human activity to map ecological integrity throughout a region. Most of these models are largely driven by human developments, however, and are limited in incorporating other measures to characterize ecosystem composition, function, and structure. We built upon these approaches by developing a model using geospatial datasets on current and future human activity, as well as incorporation of other indicators of ecological integrity (e.g., vegetation departure and habitat fragmentation). Our approach involved assigning relative scores to anthropogenic geospatial datasets and parameterizing each layer with a distance decay function to perform a geographically-weighted regression that expressed ecological integrity as a function of distance from the mapped anthropogenic feature.
Integrating the mapped results for all anthropogenic features and other landscape measures of integrity, the resulting composite model provides a map surface of relative ecological integrity within the landscape. This model serves as a general indicator of ecological integrity based upon a regional context of human activity, fragmentation, and change in habitat composition. Several applications of the modeling results for land use and mitigation planning for renewable energy development are discussed. For example, evaluation of landscape assessment models within protected areas and areas warranting protection for biodiversity sustainability may inform land managers on mitigation planning opportunities. Ecological integrity models can also be integrated with regional climate change models to evaluate potential cumulative landscape-level impacts. In addition, landscape assessment models may be useful in informing future land use allocation decisions and other federally-regulated decisions under the National Environmental Policy Act (NEPA).