Ecological Disaster Risk Assessment In Ordos

This paper mainly using Remote Sensing Geographic Information Systems (GIS) technology, according to "ecological environment evaluation techniques (for Trial Implementation)" (HJ/T192-2006) which put into trial use on May 1st,2006, ecological environmental quality assessment offered for Ordos city area. On this basis, through the exploration of geographic information system technology, this paper compiled the ecological disaster level zoning maps and finally discussed the ecological disaster risk management measures. Based on the land utilization and desertification figure of Ordos city that obtained form the interpretation of 2000,2005 and 2007 and 2009 years'remote sensing images, in accordance with statistical data of ecological disasters in many years, namely, select eight factors including drought, sandstorm, fire, heavy rains, storm, hail, frost and snow storms, etc, offered the superposition analysis and evaluation for Ordos city area, completing Ecological disaster risk evaluation map of Ordos city area. Takes the lake, forest land, shrub land, open forest land and other woodlands, high covering grassland, the covering grassland, low covering grassland, wetland, farmland, construction land and unused land as the vulnerability analysis index, with GIS analysis software, executes the superposition analysis for the risk evaluation map and vulnerability figure, completing ecological disaster risk zoning map of Ordos city area. Division results show that the GIS method can conduct efficiently for spatial analysis and integrated analysis to the influence factors of ecological disaster. This map can reduce the ecological disaster risk through the land use planning decisions of different risk zones in ecological disaster-prone areas. In addition, it can also provide the ecological disaster risk information for decisions in ecological disaster-prone areas.The results showed that plant coverage of Ordos City is relatively high as a whole, and also rich in biological diversity. But there were numerical gaps in evaluation index of same area of each banner county in different years. Classification of biological environment condition change degree of eight banners (area) showed that only wushen banner has slight changes in period from 2007 to 2009, and the others are no obvious change. Through calculation and analysis, Ordos city each banner (area)'s risk evaluation showed that in study area, fifth class dangerous region account for 11.65% area of the hole region, forth class dangerous region account for 26.97% area of the whole region, third class dangerous region account for 20.18% area of the whole region, second class dangerous region account for 28.04% area of the whole region, first class dangerous region account for 13.18% area of the whole region. The ecological disaster zoning map showed that ecological disaster risk in Ordos city area's northern part was higher than the risk of ecological disaster in the south, which is closely related to precipitation, vegetation cover and land degradation. Ordos city each flag (area)'s ecological disaster risk division results was fifth class risk area has less proportion, for 6.00% proportion; The proportion of second class risk area and third class risk area were basic and same, the percentage was 12%; first class risk area had the maximum proportion, the percentage of the four periods were 7.95%, respectively 64.85% and 60.86%61.54%, respectively.