利用遥感技术分析鄂尔多斯草原鼠虫害图斑

Analysis of rodents and pests damage spot in Erdos City grasslands based on GIS

应用地理信息系统代替人工完成的海量地理空间信息存储和处理,可以快速便捷完成空间信息与属性信息的查询和检索工作,在空间信息中草原鼠虫害图斑面积计算是草原鼠虫害发生面积制图数据处理的必需工作。草原鼠虫害监测中,需要绘制各旗(区)鼠虫害发生区域,并在图上进行面积计算,鄂尔多斯市草原站从2009年第1次依据旗(区)的数据绘制出鼠虫害面积分布图,由于数据导入图层后发现控制点的精度偏低,在面积计算中,大部分图斑面积显示的发生区域面积偏离实报面积,经过计算,虫害危害面积误差率高达37%,严重面积误差率6%,鼠害危害面积误差率为48%,严重危害面积误差率是35%,通过修正偏移出界的控制点后重复性计算,对比修正前后,发现出现面积偏离实报面积旗(区)是鄂托克旗、乌审旗、伊金霍洛旗和东胜区,主要是集中发生区面积越界线和两个图斑重叠,造成面积重复性计算,偏离实测面积,经过修正后,图斑分区计算,可降低面积误差,结果接近实报面积。

Application of geographic information system（GIS）instead of manual handing achieves mass geo- spatial information storage and processing, can help complete the inquiry and retrieval of spatial informa- tion and attribute information quickly and easily. In space information, it was necessary to analyze the fig- ure spot area of grassland with pests and rodents for graphics data processing the area. It was useful to draw the region of rodents and pests of all banners and districts, and calculate the area on figure in order to monitor grassland pests and rodents. Area distribution of pests and rodents has been drawn using software in the grassland station of Erdos City since 2009. The original frame of axes were converted into degree format based on the data collected from banners and districts. The distribution map on pests and rodents of Erdos was achieved after topology processing of data imported in layer, however, the precision of the con- trol point was very lower which resulted in that the calculating area was not in accordance with actual reported area. The error of pest damage area was as high as 37% and the error of serious damage area was 6%. The error of rodents hazard area and serious damage area were 48% and 41%, respectively. Banners of calculating area overpassed real area included Etuoke Banner, Wushen Banner, Ejin Horo Banner, and Dongsheng District after revising control points out of boundary, repeating calculation and comparing the