基于突变级数法的甘肃黄土高原沟壑区水土保持综合治理效益评价

Assessment of the benefits after comprehensive treatment for soil and water erosion based on catastrophe progression method in gullied loess plateaus Gansu

【目的】评价甘肃黄土高原沟壑区1988-2011年水土保持综合治理的效益,完善区域水土保持效益评价体系和方法.【方法】基于甘肃省水土保持统计年报等统计资料,采用突变级数法对1988-2011年甘肃黄土高原沟壑区水土保持综合治理效益进行分析评价.【结果】高原沟壑区全区水土保持综合治理效益评价值由1988年的0.298提高到2011年的0.856.1988～2011年间高原沟壑区各县区水土保持综合治理效益评价值介于0.128～0.824之间,1988水土保持效益整体较差,泾川县（0.285）、正宁县（0.299）的评价值相对较高;2000年正宁县（0.512）的评价值最高,镇原县（0.357）的评价值最低;2011年西峰区（0.824）的评价值最高,镇原县（0.638）的评价值最低;2011年与1988年对比,西峰区和崇信县的评价值增加相对较大,分别增加了0.663、0.673,而镇原县的评价值增加较小,增加了0.462.【结论】经过23a的水土流失综合治理,高原沟壑区水土保持综合治理效益显著提高;2000年以后梯田建设对水土保持效益提升的贡献相对减小,退耕还林（草）工程对水土保持效益提升的贡献相对增大.

[Objective] In order to evaluate soil and water conservation benefits from 1988 to 2011 in Gullied Loess Plateaus and to improve the system and methods of evaluation on soil and water conservation benefits. [Method] This paper evaluated benefits of soil and water conservation from 1988 to 2011 in Gul- lied Loess Plateaus Gansu with catastrophe progression method, which was based on the statistics from Soil and Water Conservation Statistical Yearbook of Gansu province. [Result] Evaluation value of soil and wa- ter conservation benefits in Gullied Loess Plateaus increased from 0. 298 in 1988 to 0. 856 in 2011. Evalua- tion value of soil and water conservation benefits of all counties varied from 0. 128 to 0. 824 from 1988 to 2011. Benefits of soil and water conservation was poor integrally in 1988, Evaluation values in Jingchuan and Zhengning Counties were 0. 285 and 0. 299 respectively, were much higher than other counties. In 2000,Evaluation value in Zhengning Country was the highest, while that in Zhengyuan Country was the lowest. In 2011, Evaluation value in Xifeng Country was the highest, while that in Zhengyuan Country was the lowest. Compared to 1988, evaluation values increased by 0. 663 and 0. 673 in Xifeng and Chongxing Counties, performed better than that in 2011. A poorer performance was found in Zhengyuan County, valu- ation value only increased by 0. 462. [Conclusion] After 23 years of comprehensive treatment for soil and water loss, benefits of soil and water conservation of Gullied Loess Plateaus increased significantly. After 2000, terraced construction had little contribution on improvement of benefits of soil and water conserva- tion, while Grain for Green Project had much contribution on improvement of benefits of soil and water conservation.