摘要
研究地点位于半干旱的黄土高原区,在坡向导致的土壤水分差异的基础上,分析该区域撂荒草地和人工林地土壤水分随退耕年限的变化特征,进而以自然草地为参照,分析不同坡向人工林地土壤水分亏缺程度。结果表明:总体上,阴坡土壤水分显著高于阳坡,撂荒草地、自然草地和林地土壤水分在阴/阳坡之间的差异分别为:3.1%、2.6%、1.5%;可见,人工林地降低了由坡向导致的土壤水分的差异。在阴/阳坡上,撂荒草地土壤水分随退耕年限增加皆呈显著增加趋势,并且,总体上,土壤水分的增加程度随年限增加而增大,尤其在深层的土壤水分。而林地土壤水分在阴坡和阳坡皆呈显著降低的趋势;通过对比阴/阳坡不同土层土壤水分随退耕年限变化趋势,阳坡人工林地上层土壤水分(0—1m和1—2m)随年限增加降低程度有所减少,然而,较深层(2—3m和3—4m)土壤水分在后期降低程度更大,而阴坡土壤水分随年限增加的降低程度呈现与阳坡相反的趋势;人工刺槐林地导致的土壤水分亏缺程度(以自然草地土壤水分为参考)随着年限增加呈增加趋势,且随深度增加呈增加趋势,总体上,阳坡人工林地除0—1m土层的土壤水分亏缺程度高于阴坡,其余土层平均土壤水分亏缺程度在前、中、后期皆低于阴坡。
This study was conducted in the semi-arid the Loess Plateau of China. On the basis of the differences in soil water content due to different slope aspects, the dynamic characteristic of soil water content in an abandoned farmland and artificial forestland with an increase in restoration years was analyzed, and on the basis of the amount of soil water in a native grassland, the soil water deficit in the artificial forestland on different slope aspects was also analyzed. Overall, the soil water content in the shady slope was significantly higher than that in the sunny slope; the difference in soil water content between the two slope aspects was 3.1% for the abandoned farmland; 2.6%, native grassland; and 1.5%, artificial forestland. Therefore, the excessive consumption of the artificial forestland with respect to soil water diminished the difference in soil water due to the different slope aspects. The soil water content of the abandoned farmland presented a significantly increasing trend with an increase in restoration years, and the degree of increase would also increase with the increase in restoration years. However, in the artificial forestland, a decreasing trend was observed ; for the sunny slope, the degree of decrease in soil water content would decrease with an increase in restoration years at the layers of 0-1 m and 1- 2 m; however, the degree of decrease in soil water content at the layers of 2-3 m and 3-4 m would increase with an increase in restoration years, and that was contrary at the shady slope. The soil water deficit in the artificial forestland presented an enhanced trend with the progress of ecological restoration and increase in soil depth. Overall, excepting the layers of 0--1 m, the soil water deficit in the artificial forestland on the sunny slope was lower than that on the shady slope.
出处
《生态学报》
CAS
CSCD
北大核心
2017年第18期6120-6127,共8页
Acta Ecologica Sinica
基金
国家自然科学基金项目(41571503)
环保公益项目(201409055)
关键词
土壤水分
坡向
恢复年限
土壤亏缺
黄土高原
soil water content
slope aspect
restoration years
soil water deficit
the Loess Plateau
