塔里木盆地风沙灾害危险性评价

Hazard assessment of wind sand disaster in Tarim Basin

考虑到风沙灾害的发生与发展不仅与风沙灾害天气有关 ,还与其影响区的自然及社会经济状况有关 ,因此本文结合新疆的实际情况 ,以承灾体指数CH 和灾次指数ZC 的变化分析了塔里木盆地风沙灾害的空间分异规律。从ZC 的变化规律看 ,基本为由荒漠区向草原牧区、农牧交错区到农区的递减走势 ;从CH 的变化看 ,基本以库尔勒市、阿克苏市和喀什市为三个中心向四周递减的变化趋势 ,说明CH 和ZC 指数在空间分异上存在明显的错位。在此基础上 ,构建了风沙灾害危险性评价模型 ,它能综反映一个研究区的风沙致灾强度和承灾强度。研究结果表明 ,塔里木盆地南部以和田为中心的区域是风沙灾害最严重的地区和沙尘暴的起源地 ,而盆地中最大的城市———喀什市和最大的农业县———萨车县则是风沙灾害危险性最高的地区。这一结论与塔里木盆地风沙灾害的实际情况基本一致 ,说明用危险性指数DX

In this paper,the disaster bearing object index C H related to population, cultivated land, stock capacity and GDP for per unit land area and the disaster frequency index Z H related to average wind sand disaster weather days per year are determined as the main factors to calculate spatial variation of wind sand disaster in Tarim Basin. Analysis indicates that the high value regions of Z C and C H are not lapped in area coverage. Due to the occurrence and development of the wind sand disaster is related not only to weather condition but also to natural and economical situation of the area, we adopt Z C and C H as two main indexes to evaluate the hazard assessment index D x of wind sand disaster in Tarim basin. The wind sand disaster hazard assessment index D X can overcomes the shortage to evaluate only by C H or Z C, because it can synthetically explain the character of the disaster amount and the disaster bearing object. The calculating and analyzing of D X can easily find the spatio temporal pattern of the wind sand disaster in Tarim Basin. The result shows that the wind disaster and the original sand dust storm source is at southern Tarim Basin with Hotan as center, and the most risk areas are the biggest city- Kashi and the biggest county- Sache in the Basin. The result is close to actual distribution condition of wind sand disaster in Tarim Basin. Therefore, we have reasons to believe that the method is effective and feasible.