黄河上中游“农牧交错带”土壤侵蚀环境研究

A Study on Soil Erosion Environment in the"Agriculture and Animal Husbandry Interlock Zone" of the Middle and Upper Yellow River

黄河上中游“农牧交错带”侵蚀环境形成于地质时期 ,发展于人类历史时期。现代侵蚀环境有明显的地域分异 ,环境要素的主要特征是 :①降雨量具有时间上年际的波动性和年内的集中性 ,空间上分布的不均匀性 ;②地表组成物质松散 ,以沙性物质为基调 ;③植被类型简单 ,以草本植物为主 ,覆盖度低。由侵蚀环境各要素相互作用所产生的侵蚀产沙特点是 :①侵蚀产沙类型复杂 ;②泥沙来源多样性 ;③区域产沙具有空间的不均匀性、年际的波动性和时间的集中性。农牧交错带生态环境属性难以改变 ,但是人们可以通过退耕还林还草调整人 -地关系 ,调整土地利用结构。

The soil erosion environment in the agriculture and animal husbandry interlock zone of the middle and upper Yellow River formed in the geological period and develops in the mankind historical period. There is obvious difference in space for the modern erosion environment. Characteristics of factors in the erosion environment are as follows: ① For precipitation, there are inter annual fluctuation and inner annual concentration in time and non even distribution in space; ② Loose composition materials of the earth surface are characterized by a sort of sandy materials; ③ Simple vegetation type with low coverage is dominated by herb. Sediment yield caused by interaction among the factors in the erosion environment has the following characteristics: ① Complex erosion types; ② Multiplex sediment sources; ③ Non even distribution in space and inter annual fluctuation and concentration in time. At last, it is pointed out in this paper that it is difficult to change eco environmental properties of the agriculture and animal husbandry interlock zone, but it is possible to restrain erosion and restore the environment by adjusting relationship between man and the earth through returning crop plots to forestry and grassland, adjusting land use structure and industry structure.