%A Bo Ma, Xiaoming Wang, Xiaoqing Liu, Zhenghuan Wang %T GIS analysis of the spatial relationship between plateau pika burrow distribution and vegetation distributional patterns %0 Journal Article %D 2011 %J Biodiv Sci %R 10.3724/SP.J.1003.2011.08080 %P 71-78 %V 19 %N 1 %U {https://www.biodiversity-science.net/CN/abstract/article_8238.shtml} %8 2011-01-20 %X

The plateau pika (Ochotona curzoniae) is a keystone species in alpine meadow ecosystems on the Tibetan Plateau. Therefore, ecological studies of the relationship between plateau pika habitat use and the stability of alpine meadows are important. However, little information is available about large-scale spatial relationships between plateau pika habitat use and vegetation distribution. Therefore, we studied this topic using Geographic Information System (GIS) analyses. The number and position of active plateau pika burrows were sampled along seven line transects totaling 2,423 sampling units, 19 km in length, in a 44 km2 study area in Yunbo Gou, Shiqu County, Sichuan Province during September 2008. Historically, domestic livestock grazing and other human activities were rare in this area. A no-grazing policy has been in effect since 2006, thereby removing livestock competition in the study area. Normalized Difference Vegetation Index (NDVI) values within the study area were extracted from a CBERS-02 remote sensing image taken September 18th, 2008. A digital elevation model (DEM) of the study area was established based on a digitized topographical map of Shiqu County, and slope values within the study area were subsequently extracted using the DEM. NDVI and slope values were compared with the number of plateau pika burrows in each sampling unit. A Bonferroni z test revealed that numbers of pika burrows were lower than expected in units with low NDVI values (NDVI of 0.1-0.3), not different than expected in middle NDVI groups (0.3-0.4), and higher than expected in high NDVI groups (0.4-0.6). A linear regression model found a significant positive correlation between NDVI value and pika burrow count (y = 16.50 x + 0.87; R2 = 0.78, P < 0.001). In contrast, no linear relationship was detected between slope and pika burrow number (linear regression, R2= 0.04, P = 0.441). This study showed that plateau pikas use areas with higher vegetation coverage more than areas with lower vegetation coverage in the absence of livestock competition. Our results lend some support to the conclusion that the pika’s natural use of vegetation does not accelerate the destruction of the alpine meadow vegetation in this region.