黄土高原多沙粗沙区侵蚀产沙的多维临界  

The Multi-dimensional thresholds of sediment yield in the area with abundant and coarse sediment on the Loess Plateau

作　　者：陈劭锋[1] 刘全友[2] 陆中臣[2] 李忠艳[3] 

机构地区：[1]中国科技大学商学院 [2]中国科学院生态环境研究中心,北京100085 [3]华北电力大学数理系,北京102206

出　　处：《生态学报》2007年第8期3277-3285,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(40571062)~~

摘　　要：黄土高原多沙粗沙区侵蚀产沙受到自然要素和人文要素的综合作用。从该地区侵蚀产沙的自然和人文影响要素识别入手,比较系统地揭示了各主要影响因子侵蚀产沙过程的单维临界响应及其发生的内在机理,在此基础上建立了侵蚀产沙要素交互作用的多维临界综合集成模型,并依据该模型定量计算出目前该地区自然和人文要素及各主要影响因素分别对侵蚀产沙的贡献,最后提出了该地区水土流失治理的调控目标和现有治理措施的调整思路。研究结果表明:(1)由于该地区自然和人文要素的交互作用,使得各影响因素侵蚀产沙的单维临界响应发生位移和变化,达到复合临界极值的多维临界点趋于降低或基本保持不变。(2)该地区的侵蚀强度在自然和人文要素的交互作用下仍在加剧。其中,可分离的自然因素作用占80%左右,人为因素作用占20%左右。就自然因素而言,降水对产沙强度的贡献最大约为61%;(3)该地区水土流失的治理速度抵不上人为破坏速度;(4)在多沙粗沙区人为因素产沙贡献中,农业结构的贡献最大。这意味着该地区生态环境治理与建设首先要把农业结构调整和优化置于第一位。Sediment yield in the area with abundant and coarse sediment on the Loess Plateau is determined by natural processes and human action. This paper first distinguishes the natural and human factors influencing the sediment yield in the area, and then develops a single threshold response of each factor to the process of erosion and its intrinsic mechanism. On this basis, an integrated model of multi-dimensional thresholds taking into consideration the interactions between natural factors and human factors controlling sediment yield is developed to calculate the contribution of both natural factors and human factors to sediment yield. Also, the model quantifies the regulating objectives for soil and water conservation and the adjustment of the current measures taken to combat soil erosion are suggested. The results show that： （1） under the interaction between natural and human factors, the single threshold value of each factor tends to decline or be unchanged when a maximum value of the model is reached. （2） The intensity of erosion in the area is still increasing, almost 80% of which being caused by natural factors and 20% by human factors. Precipitation is the main factor that explains the intensity of soil erosion （about 61% ）. （5） Water and soil conservation techniques lag behind and can not prevent soil erosion and degradation. And （4） agricultural practice is the main human contributor to sediment yield, which implies that soil conservation methods should focus on the agricultural practices.

关 键 词：黄土高原 粗沙多沙区 侵蚀产沙 影响要素 单维临界 多维临界 调控 

分 类 号：P931.6[天文地球—自然地理学]