2009—2010年中国西南岩溶区旱情分析与减灾对策——以广西岩溶区为例

Drought Causes and Countermeasures of China Southwest Karst Area from 2009 to 2010——A Case in Karst Area of Guangxi

为研究中国西南岩溶区抗旱减灾对策,分析了2009年秋至2010年春广西岩溶区的旱情:与常年同期相比,大部分地区降水量偏少20%～70%;气温除11月和4月偏低外,其余7个月偏高0.7～2.8℃;一些地方持续8个月无有效降雨;岩溶区农作物受旱面积约为100万hm2,约占岩溶区耕地面积的70%,干旱分布与岩溶发育区具有高度的一致性。极端气候是诱发西南岩溶区大旱灾的主要原因,岩溶区水文地质和地貌条件是旱情加剧的独特因素,人为因素造成的工程性缺水和环境恶化也是主要因素之一。提出了加强旱情监测、预报、预警和应急能力,加大水利工程建设力度,加强水利工程后期管理以及维修养护,重视岩溶生态恢复、重建和保护等抗旱减灾对策。

To study the countermeasure of drought relief of karst area in southwest China,the drought situation of karst area in Guangxi from the fall of 2009 to the spring of 2010 is analyzed.The mean precipitation decreased 20%-70% compared with the time in most parts,while temperatures raised 0.7-2.8 ℃ except November and April.There was no effective precipitation for 8 months in some areas.About 100×104 hm2 were agricultural drought areas,about 70% cultivated area in karst region.The drought distribution has a high concordance with karst distribution.Extreme climate is the main cause of this severe drought in southwest China.The hydrogeological and landform condition are the unique factors contributed to the drought in karst area.Engineering water shortage and environmental deterioration caused by artificial factors are also one of the main factors.The countermeasures on drought are proposed finally,including enhancing the surveillance,monitoring,forecasting and emergency response capacity of drought disaster,building,managing and maintaining hydraulic engineering construction,attaching importance to ecological restoration,reconstruction and protection in karst area.