我国农牧交错区土地退化研究——以宁夏盐池县为例

 从荒漠化发展历史角度出发,通过收集历史资料和固定样地观测,采用数学分析方法,利用马尔可夫链(Markov)模型和模糊模式识别方法对盐池荒漠化现状、动态变化以及荒漠化治理措施效益进行分析。结果表明:1)盐池县近半个世纪以来土地荒漠化呈急剧扩大趋势,荒漠化土地面积平均年增长率4.03％。2)盐池县荒漠化主要原因是在脆弱生态环境基础上,人为不合理经济活动所致。3)如果能做到严格执法,全面落实禁牧政策并加强防沙治沙工程管理,盐池县荒漠化土地将得到全面治理,否则盐池县荒漠化形势将继续恶化。认为能否全面落实禁牧和退耕还林政策,将直接影响盐池县荒漠化防治。

Study on the Land Desertification and Its Control in the Crop-grazing Crisscross Area of China:Taking Yanchi County in Ningxia Hui Autonomous Region as Example

Based on historical data and by fixed sample plot observation with mathematical methods of Markov Chain and Fuzzy Pattern Recognition, desertification pattern, development and its trend in transition region from agricultural area to rangeland of Yanchi, Ningxia were studied. The results show that ( 1 ) the annual increment rate of desertification in Yanchi in past 40 years was 4.03% . (2)the main causes of desertification in Yanchi are human irrational activities of overcultivation,overgrazing and over collection of fuel wood and Chinese herb medicine based on the fragile ecological condition. (3)desertified land in Yanchi will be treated by strictly implementation of law and regulation related desertification combating and national key projects of reversion of arable land to forest and rangeland, otherwise, desertification will become more serious. The continuous implementation of policy of reversion of arable land to forest and rangeland will be the key factor related to the desertification combating in Yanchi.