沙漠—河岸过渡带土壤养分与盐分的空间变异  

Spatial Variability of Soil Nutrients and Salt in Desert-Riverside Ecotone

作　　者：李朝生[1] 慈龙骏[1] 于春堂[1] 杨晓晖[1] 王忠 白飞 

机构地区：[1]中国林业科学研究院林业研究所国家林业局森林培育实验室,北京100091 [2]亿利资源集团生态项目部,内蒙古独贵塔拉017600

出　　处：《农业环境科学学报》2005年第4期643-647,共5页Journal of Agro-Environment Science

基　　金：国家自然科学基金(30171205);"十五"重点科技攻关项目"鄂尔多斯高原沙地农牧业开发技术及示范"(2002BA517A03)

摘　　要：以库布齐沙漠与黄河河岸之间这一具有重要生态学功能和价值的过渡带为研究对象,利用地统计学方法对其A、B、C3层土壤的全氮、速效磷、速效钾、全盐、pH、有机质等进行了分析。结果表明,过渡带土壤都较为贫瘠,且其土壤养分和盐分有随深度增加而降低的趋势;除速效钾含量较高外,有机质和氮严重缺乏,磷分布极不均匀;绝大部分土壤属于碱性至强碱性,且盐碱危害较重,盐分类型以碳酸盐和氯化物为主。A层与其他两层相比,随机作用与小尺度控制作用占明显优势,而相关尺度与空间异质性的差异较大;即A层土壤要素空间异质性的形成,过程与作用更具趋同性,而尺度与格局却更具有趋异性;其导因是风沙流在过渡带所产生的随机作用以及此后形成的反馈作用,土壤元素的地球化学循环和生物地球化学循环的途径各异也是其重要原因。There is a great area of saline meadow, length to hundreds of kilometers and width from hundreds to thousands of meters, in the low step and the floodplain between the Kubuqi Desert and the riverbank of the Yellow River. The long and narrow ecotone is a last barrier cumber in prevent desert from invasion and sand moving to river, and accordingly it plays an important ecological value and function. However, recent years, the defending function of the belt meadow weakens with its width decreasing enormously. In order to provide scientific basis for sustainable development, utilization and protection in this region, we analyzed by using geostatistics the total nitrogen, available phosphorus, available potassium, total salt, pH and organic matter of the soil in the original and remnant meadow for three layers, A, B and C. The results showed that the soil in the ecotone was infertile and trended to more infertile with the depth deeper. The organic matter and the total N were badly off except for available K, and the distribution of available P was asymmetry extremely. Compared to the other two layers, the stochastic function and the function controlled by small scale in A layer were predominant, while the difference of the correlation scale and the spatial heterogeneity was obvious, i.e. the process and the function were more homologous in the formation of the spatial heterogeneity of A layer, while the scale and the pattern were more heterogeneous. The cause of that was the stochastic function produced by the wind-sand flow in the ecotone and the feedback function formed subsequently, and the other one of the causes was that the routes of the soil elements in the geochemistry cycle and the biogeochemistry cycle were different.

关 键 词：土壤养分 土壤盐分 沙漠-河岸过渡带 空间分异 地统计学 

分 类 号：X171.1[环境科学与工程—环境科学]