Distribution and Geographic Division of Grasshopper in Shaanxi Based on GIS Techniques

This paper deals with the distribution and geographic division of grasshopper in Shaanxi province using GIS (geographic information system) techniques. 593 longitude and latitude grid cells (0.2°×0.2°) were used to count the species number of grasshopper and multi-analysis hierarchical cluster method was used in the cluster analysis. The results showed (1) the number of grasshopper species of southern Shaanxi are greater than that of the rest of Shaanxi, and the number of grasshopper species of Ordos Plateau are greater than that of Loess Plateau of northern Shaanxi. The 593 distributional units are clustered into 9 groups with proximity coefficients of 0.538 which resembles the physical division of Shaanxi. However, there are some differences in the distributional units as follows: Qinling mountain is divided into a southern and northern slope; Shangnan Hill is separated from Qinling Mountain; Ankang Area and Bashan Mountain from a single cluster of one group; Bashan Mountain and Micang Mountain are clustered into two paratactic groups. The cluster results also showed that there is a close relation between the geographic distribution of grasshopper in Shaanxi and its environment, and the distribution pattern of grasshopper has obvious zone differences. We conclude that the diversification of the geography and climate types of Shaanxi are the main reasons of the diversification of grasshopper species.