旱灾对石漠化影响评估及灾后石漠化防治分区

以西南五省区(四川、重庆、云南、贵州、广西)为研究对象,将岩性、坡度、降水、土地利用、土壤类型、植被覆盖度、与居民点距离、人口密度作为评价指标,研究了石漠化敏感性及西南旱灾导致的变化,并以贵州省兴义市为示范,制定了旱灾后石漠化防治分区. 结果表明:干旱可提高石漠化敏感性,受旱灾程度越深,石漠化敏感性增强越明显. 旱灾导致西南五省区石漠化极重度敏感区和重度敏感区面积分别增加了777和16 484 km2. 贵州省兴义市石漠化敏感性显著变化面积最大,达到石漠化总面积的54%,灾后治理区、监督区、预防区的面积分别为110.9、221.8和509.1 km2,其中需对33.7 km2的石漠化区域进行优先治理. 

Analysis of the Impacts of Drought on Rocky Desertification and the Regional Prevention of Rocky Desertification after Drought

Taking Chongqing, Sichuan, Yunnan, Guizhou, and Guangxi as the research areas, and based on the evaluation indices of lithology, slope, rainfall, land use, soil type, vegetation coverage, distance to residents, and population density, the changes of rocky desertification sensitivity caused by the drought from fall 2009 to spring 2010 were investigated. Taking Xingyi City in Guizhou Province as the example, rocky desertification prevention after drought for the whole study area was researched. The results showed that drought could enhance the sensitivity of rocky desertification, and the more serious the drought, the more obvious the enhancement of rocky desertification sensitivity. The extremely severe area and the severe area of rocky desertification were increased by 777 and 6,4 km², respectively, in the five southwest provinces after the drought. The most significant change of rocky desertification sensitivity occurred in Xingyi City of Guizhou Province, which accounted for 54% of the total area of rocky desertification. After the drought, the controlled, supervised and prevented areas of rocky desertification of Xingyi City were 110.9,1.8 and 509.1 km², respectively, of which 33.7 km² should be put under prioritized governance.