The effects of alternative future development scenarios on ecological processes and social-ecological resilience in Central Oregon

Graduation date: 2010This research sought to explore the implications of different tenure regimes for both\ud landscape-level ecological processes and the overall resilience of a social-ecological\ud system in Central Oregon. The purchase by an investor of former industrial timberlands\ud known as the Bull Springs tract raised the specter of dispersed residential development on\ud the periphery of Bend, Oregon, leading to legislation redefining tenure in the region. This\ud research examined how different forms of tenure on the tract would affect landscapelevel\ud ecological processes and how the enacted tenure redefinition might affect the\ud resilience of the social-ecological system to future perturbations. Data simulating the\ud future vegetation conditions under two tenure scenarios on the Bull Springs – dispersed\ud residential development and working forest management – were used to map habitat for\ud three species representing different ecosystem services. Landscape pattern metrics were\ud used to compare the simulated differences in spatial patterns of mule deer (Odocoileus\ud hemionus) habitat, American marten (Martes americana) habitat and old-growth\ud ponderosa pine (Pinus ponderosa) woodlands. The results were then interpreted using a\ud social-ecological systems framework describing linkages between tenure and ecological\ud processes. Results from the simulation modeling showed multifunctional habitat patches\ud for mule deer became more isolated and smaller when the Bull Springs was developed,\ud and development of the tract led to greater average isolation of habitat patches, lowered\ud extensiveness across the landscape and a reduction of most measures of total habitat area\ud for both mule deer and American marten. Ponderosa pine woodlands grew substantially\ud in quantity under both scenarios, but the development of the Bull Springs removed a\ud large swath from the middle of the ponderosa pine belt, interrupted north-south\ud connectivity and reduced the extent of potential ponderosa pine woodland conditions.\ud Development projected to occur outside the Bull Springs largely determined the\ud cumulative impacts of both scenarios, but working forest management would be an\ud improvement over development for most metrics for the three species. With respect to\ud resilience, the legislative tenure redefinition would change the linkages between\ud communities in the region and the ecosystem services of value, and these linkages could\ud vary in strength and in the scale of applicability. Understanding how forestland\ud ownership change intersects with landscape ecology as land uses change is critical for\ud evaluating policies that manage these changes. Identifying the ecological impacts avoided\ud by managing the Bull Springs as a working forest can inform landscape-level planning to\ud ensure that future development does not recreate these losses elsewhere in the region.\ud Study of these components and linkages contributes to broader efforts to understand and\ud manage the dynamics of social-ecological systems at multiple scales to make social wellbeing\ud and ecological integrity resilient to future disturbances