Biodiv Sci ›› 2011, Vol. 19 ›› Issue (1): 71-78.DOI: 10.3724/SP.J.1003.2011.08080

• Special Issue • Previous Articles     Next Articles

GIS analysis of the spatial relationship between plateau pika burrow dis-tribution and vegetation distributional patterns

Bo Ma1, Xiaoming Wang1,3, Xiaoqing Liu1, Zhenghuan Wang1,2*   

  1. 1School of Life Sciences, East China Normal University, Shanghai 200062

    2Shanghai Key Laboratory of Urbanization & Ecological Restoration, Shanghai 200062

    3Shanghai Science & Technology Museum, Shanghai 200127
  • Received:2010-04-03 Revised:2010-09-03 Online:2011-01-20 Published:2011-04-01
  • Contact: Zhenghuan Wang

Abstract: 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 bur-rows 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 In-dex (NDVI) values within the study area were extracted from a CBERS-02 remote sensing image taken Sep-tember 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 us-ing the DEM. NDVI and slope values were compared with the number of plateau pika burrows in each sam-pling 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 con-trast, 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.