晋西北黄土区不同植被春季土壤水分动态变化特征研究

以晋西北黄土丘陵区为背景,对当地有代表性的植被(乔木类小叶杨林、灌木类沙棘林和柠条、油松-小叶杨混交地及撂荒地)为主要研究对象,系统地对5种不同植被土壤水分含量状况、垂直分布特征及变异情况进行分析,结果表明:在0~600 cm土层深度范围内,不同类型植被的平均土壤水分含量高低依次为撂荒地油松-小叶杨混交林沙棘林柠条小叶杨,且总体都呈现出先增加后减少然后趋于恒定的变化趋势;其中乔、灌木的土壤水分含量最大值均出现在150 cm~220 cm之间,而撂荒地在320 cm处出现最大值,5种植被类型的最小值大都出现在0~20 cm的表层土壤。最后,根据不同植被的土壤水分分布分层的定量分析,将土壤剖面划分为:易变层(0~100cm)、活跃层(100 cm~200 cm)、次活跃层(200 cm~300 cm)和相对稳定层(300 cm~600cm)。因此,根据本区域土壤水分变化特点,在进行植被恢复建设过程中,依据因地适宜原则,实行乔-草或乔-灌-草相结合的植被配置模式。

Research on Dynamic Characteristics of Soil Moisture in Spring of Different Vegetation in Loess Area of Northwestern Shanxi

This research systematically analyzes the moisture content of soil, the vertical distribution characteristics and the variation of five different kinds of vegetation in the loess hilly area of northwestern Shanxi taking some local representative vegetation such as populus simonii forest （arbor）, sebuckthorn forest and caragana korshinskii kom（shrub ）, and pine- poplar mixed land, and abandoned land as the main research objects. The results show that： in the soil depth of 0 cm～600 cm, the average soil moisture content of different types of vegetation is, in order, abandoned land 〉 pine- poplar mixed land 〉 seabuckthorn forest〉 caragana korshinskii kom〉 populus simonii; and generally presents a change trend of that the soil moisture content firstly decreases, then increases, and then again tends to be constant; among them, the maximum soil moisture content of arbor and shrub occurs at the range of 150 cm-220 cm, and the maximum soil moisture content of the abandoned land occurs at 320 cm, while the minimum of the the maximum soil moisture content of all the five vegetation types is in 0 cm～20 cm on the topsoil ; finally, according to different vegetation＇ s quantitative analysis of their soil moisture distributions, the soil profile is divided into the variable layer（0 cm～100 cm）, the active layer （ 100 cm～200 cm）, second active layer （200 cm～500 cm） and a relatively stable layer （500 cm～600 cm）. Therefore, based on the features of the change of soil moisture in this area, the configured combination mode of arbor - grass or arbor-shrub-grass can be implemented during the construction of vegetation restoration.