Scope and Methods
This effort evaluates the effects of future land uses on vegetation and wildlife habitat and is designed to illustrate potential management actions that may minimize land-use impacts. The entire WLCI landscape will be included in a spatially-explicit simulation framework to explore future potential land-use effects and the potential influence of future climatic conditions. Future potential energy development will be simulated along with elements of climate change from climate models to determine potential types and patterns of land cover change. Scenarios of future change will be employed to determine conditions (land uses and patterns) that minimize long-term effects on vegetation conditions and wildlife resources, including migration corridors, sage-grouse core areas, and habitat. The results of this study will aid in identifying the spatial and temporal patterns of land uses that may minimize effects on wildlife habitat. A frame-based model is a type of knowledge-based model used to illustrate system states and state changes, whereby the generalized alternative states of a system are represented as “frames” and knowledge about factors influencing a frame is used to model the temporal transition among frames. Frames consist of one or more key plant species or species groups. The simulated landscape in the modeling system is represented as a lattice of equal-sized cells called landscape elements, which are initialized with frames that represent current vegetation. Other biophysical properties are stored for each landscape element.
The WLCI conceptual models for contemporary ecosystems define all possible ecosystem states and the pathways and triggers of transition among states in response to natural disturbances and human-mediated stressors. Disturbances within the natural range of variability are modeled to mediate changes in variants of the native state. Degraded states (outside the range of native conditions) induced by stressors are explicit, and assumptions about the intensity or severity of a stressor determine the probability of transition to a degraded state. Degraded states are described by changes in species composition, and by impacted soil properties (soil erosion, reduced soil stability). These states become susceptible to conversion (subdominant replacing dominant species) or invasion (new species assemblage). Dynamic features related to soil conditions of a degraded state, climatic conditions, and propagule abundance (which considers ‘migration’ barriers) determine the species that invade the landscape element containing the degraded state.