陕西蝗虫地理分布格局的聚类分析

CLUSTER ANALYSIS ON THE DISTRIBUTION PATTERNS OF GRASSHOPPER IN SHAANXI

以593个经纬网格单元(0.2°×0.2°)统计陕西蝗虫分布数据,根据陕西蝗虫分布范围将其分为全布种(593个网格单元中有分布)、多布种(9个以上网格单元有分布)和独布种(9个以下网格单元有分布)3类。以分布区域为性状作聚类分析,在相关性系数为0.153处,将多布种分布划分为12组,在此基础上运用GIS的空间叠加分析功能确定各组蝗虫的地理分布格局。结果表明:1)秦岭山脉对陕西蝗虫的阻限作用较明显,秦岭以南蝗虫物种以东洋型种为主,秦岭以北以古北型种为主;2)陕西蝗虫的地理分布格局与全国基本一致;3)太白山地区蝗虫物种多样化程度较高,是生物多样性研究的热点区域。

This paper studied the geographical distribution pattern of grasshoppers in Shaanxi by GIS （Geographic Information System） techniques. Using 593 longitude and latitude grid cells （0.2°× 0.2°） to count the distribution data of grasshopper, and according to the range of distributions, grasshoppers in Shaanxi were divided into three groups： 1 ） all-area- distributed species （distributed in all the 593 grid cells）; 2） more-area-distributed species （distributed in more than 9 grid cells） ; 3） one-area-distributed species （distributed in less than 9 grid cells）. The more-area- distributed species were clustered based on distributions, and it could be divided into 12 groups with the proximity coefficients of 0.153. Then used spacial layers analysis of GIS to judge the distribution pattern of each group. The results show： 1 ） the obstruct function of Qinling mountain to grasshopper is distinct. The species in south of Qinling is predominated by Palaeoarctic realm species while north of Qinling is predominated by Oriental realm species. 2 ） The geographical distribution pattern of grasshopper in Shaanxi is almost consistent with the pattern all over China. 3 ） The regions of Taibai mountain have a higher biology diversity. It is a hot spot for the study of biology diversity.