植被工程与水土保持关系分析

五华河中游的乌陂河流域水上流失严重,人为恢复植被的速度仍赶不上自然水土流失的速度。本文在分析植被的作用,植被工程的特征与作用等问题的基础上,提出了实施植被工程的三条基本原则和两个不容忽视的问题,最后讨论了植被工程的开发利用问题。

The Formation of Loess Plateau and Its Harnessing Measures

By taking the formation of mud-rain and dust-rain and other mud "granular fine sand", and the inlaying of fine mineral grain into coarse sand and other phynomena, as the sole characteristic for the formation of loess plateau caused only by the blowing and carrying of wind, and after checking each different periods'loess,which were formated for 2.5 million years long, it was believed that the formation of the loess plateau was indeed the causes that the loess dust, which was carried by wind from west, met the moist airflow from east then continuously fell down then accumulated gradually. The loess layer accumulated this way, in which the structure appears frame touch, possessed fine aeration and permeability originally, later it is affected by the reproduction of vegetation, especially by the effect of root system of grass, the cha racter is strengthened. This is the sole background and source for the accumulation of loess up to 100 meters and formulating the complete loess plateau--ancient soil under the natural condition. The soil and water loss violently, the main reason was human's destroy on natural vegetation, thus it thoroughly destroyed the permeability and anti-scouring of soil. So recent harnessing measures on loess plateau are forced to be "no-site-retain all precipitation" as the strategic goat and adopt measures as "cereal crops are planted on plain and plateau land, forest and fruit tree are set on gullies, grass and shrub are located on hillside";and combining with the social and economic requirement, to arrange the reasonable land utilization and concrete productive measures.