Session Information
| Session | Poster Session | | Date | Monday (2008-04-07) | | Time | 5:00 PM - 7:00 PM | | Room | Grand Terrace |
Presentation Information
| Presenter | Shanley Thompson | | Title | Landscape fragmentation in coastal temperate rainforest watersheds | | Affiliation | University of British Columbia | | Authors | Shanley Thompson, Sarah Gergel, Robert D, Jeffrey Cardille | | Keywords | Fragmentation, Landscape metrics, Late-seral forests, Natural range of variability, Watershed monitoring | | Presentation Type | Poster | Abstract:
Forested landscapes exhibit varying amounts of fragmentation due to both natural and anthropogenic causes. Using the natural range of variability as context to guide management activity (e.g., forest harvesting) is increasingly recognized as a method to manage for ecological integrity. The objective of this research is to quantify broad-scale landscape patterns within and among managed and unmanaged forests on Vancouver Island, British Columbia, Canada. Because derived Landscape Pattern Indices (LPIs) are affected by the extent of analysis, rather than calculating metrics for arbitrarily chosen, regular landscape units (e.g., rectangular images), we used more ecologically and biophysically relevant natural watershed boundaries based on Provincial GIS layers. Watershed boundaries were delineated on classified Landsat-7 ETM+ satellite imagery (circa year 2000) showing vegetation type and density. Code was then written to calculate LPIs using Fragstats software for the entirety of Vancouver Island (>30 000km2) for each of the nearly 1700 watershed basins. We determined the statistical distribution and variation in LPIs among watersheds that differed with respect to management history and ecozone. Further, because LPIs may exhibit variability solely due to topographic complexity, we used indices of terrain variability to account for differences due to terrain. This research contributes to a greater understanding of the causes and consequences of spatial pattern and provides context that can aid the sustainable management of late-seral forests. This is especially pertinent in the late-seral temperate rainforests of coastal British Columbia, Canada where forest harvesting is controversial due to different and often competing interests and visions. |
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