PARENT SESSION
Oral Session #79: Conservation Ecology: Biodiversity Case Studies and Models. Presiding: T. Rooney.
Friday, August 10, 2001. 8:00 AM to 12:00 PM. Hall of Ideas J.
Species-area curves indicate the importance of habitats' contributions to landscape-scale biodiversity.
CHONG, GENEVA1,2, STOHLGREN, THOMAS1,2, 1 2
ABSTRACT- We examined species-area curves, species composition and similarity (Jaccard's Coefficients), species richness, and fine-scale heterogeneity (ranges in species richness and cover) in 17 vegetation types to develop a composite index of a vegetation type's contribution to landscape-scale species richness. We collected data from 1-m2 to 1000-m2 scales in 147 nested plots in Rocky Mountain National Park, Colorado, USA to compare three species-area curve models' abilities to estimate the number of species observed in each vegetation type. The log(species)-log(area) curve had the largest adjusted coefficients of determination (r2 values) in 12 of the 17 types, followed by the species-log(area) curve with five of the highest values. When the slopes of the curves were corrected for species overlap among plots with Jaccard's Coefficients, the species-log(area) curves estimated values closest to those observed. Combined information from species-area curves and measures of heterogeneity may provide an accurate way to rank landscape-scale hotspots of plant diversity within regions of interest to improve the design of surveys and rapid assessments for biodiversity conservation.
KEY WORDS: species-area curves, plant diversity, habitat heterogeneity