以设在山西省阳高县的大型径流观测场为依托,研究晋北黄土丘陵区不同人工植被对水土流失和土壤水分含量的影响。结果表明,柠条、沙棘、油松植被能有效控制水土流失,蓄水能力为84.8%~95.9%,保土能力为95.2%~99.7%;植被生长的第3年和第4年,荒坡区和苜蓿区的蓄水保土能力急剧增强,第4年蓄水能力分别达82.8%和91.2%,保土能力达97.0%和98.0%;不同植被区4-9月土壤水分变异系数为7.0%~19.1%,其中油松区变异系数最大,其次为沙棘、苜蓿和柠条区,荒坡区和裸坡区变异较小,不同植被区土壤水分亏缺率为23.98%~52.66%,亏缺顺序为柠条区〉苜蓿区〉油松区〉沙棘区〉荒坡区〉裸坡区。可见,植被提高了土壤水分的变异及亏缺程度。
Based on the runoff plots located in Yanggao county,Shanxi province,effects of different vegetation on soil and water loss and soil moisture in Loess hilly area in north Shanxi province were investigated.The results showed,compared with bare land,Caragana,Hippophae and Pinus tabulaeform could control soil and water losses effectively,with the runoff reduction rate of 84.8%~95.9% and sediment reduction rate of 95.2%~99.7%;wasteland and Alfalfa could control soil and water losses effectively from the third and fourth years,with the runoff reduction rate of 82.8% and 91.2%,and the sediment reduction rate of 97.0% and 98.0% respectively in the fourth years;coefficients of variation of soil moisture were ranged from 7.0%~19.1% in different vegetation plots from April to September,and that of Pinus tabulaeform plot was the highest,Hippophae,Alfalfa and Caragana were following,and wasteland and bare land were lower;deficiency rates of soil water were ranged from 23.98%~52.66%,that were in the order CaraganaAlfalfaPinus tabulaeformHippophaewastelandbare land,implying vegetation could increase the variation and deficiency of soil moisture.