典型喀斯特石漠化小流域小型农田水利配套技术与模式

Supporting Technologies and Modes of Irrigation and Drainage for Croplands in the Typical Karst Rocky Desertification Areas

以贵州清镇市王家寨小流域为例,借助3S技术建立研究区土地利用与石漠化空间数据库,摸清不同等级石漠化分布的土地利用方式,结合经济社会和人地矛盾分析,揭示导致石漠化的主导因子。在此基础上,根据水文地貌结构,水土资源条件等综合因素,确定流域小型农田水利配套方式与布局,以洼地排涝解决内涝保护基本农田为核心,提水解决水资源短缺为重点;通过配套供水管网,田间道路,引导发展节水灌溉型早熟蔬菜。2008年工程实施,至2011年流域石漠化面积减少10.2%,强度等级明显降低,中度及以上石漠化面积减少21.23hm2,土壤侵蚀模数由治理前204.45t/(km2.a)降低到156.31t/(km2.a);人均收入提高237.9%,农业产值增产66.7%,在几次重大干旱中,流域水资源均有保障,喀斯特洼地"洼地排涝+提水灌溉"模式有序地推进了流域整体石漠化的治理。

By taking Wangjiazhai catchment in Qinzhen of Guizhou Province as an example, with the aid of 3S technique, the database of land use and rocky desertification space in research areas are set up. And the condition of land uses in different levels of the karst rocky distribution areas is obtained. In addition, combining economic society and the contradiction between man and land, the domi- nant factors leading to rocky desertification are revealed. Then research is done based on the above., a） according to geomorphologic and hydrologic structures, water and soil resources, and other comprehensive factors, the matching system of irrigation and water conservancy and its layout in the small catchment is determined, with the core of solving water draining in depressions and protecting the basic farmland and the key point of solving the shortage of water resources by motor-pumped carrying water; b） the development of water-saving and precocious vegetables would be guided by the supporting water pipe net and the field roads. From 2008 to 2011, with the implementation of the project, the area of rock desertification land reduced by 10. 2~; the grades of intense rocky desertifi- cation reduced obviously; the area of rocky desertification lands at moderate and above decreases by 21.23 hm2 ; soil erosion modulus reduced to 15 631 t/（kmz ~ a） from 204. 45 t/（km2 ~ a） before rehabilitation; the average income for each person increases by 237.9%. Agricultural output increases by 66. 7~. Although in several serious drought disasters, water resources are guaranteed. The mode of combining depressions draining with water pumping irrigation boosts the implementation of rehabilitation projects for karst rocky desertification.