| 引用本文: | 马耘秀,夏露,范毅.不同土地利用和地形条件对黄土丘陵区土壤水分的影响[J].灌溉排水学报,0,():-. |
| MaYunxiu,XiaLu,FanYi.不同土地利用和地形条件对黄土丘陵区土壤水分的影响[J].灌溉排水学报,0,():-. |
|
| 摘要: |
| 【目的】土壤水分是黄土高原干旱半干旱地区植被生长的主要限制因素，研究土壤水分变化特征及其对主要影响因子的响应规律，对该地区生态恢复建设具有重要的指导意义。【方法】本研究采用土钻法于2020年7~9月对山西省宁武县黄土丘陵区不同下垫面条件0-200 cm土层的含水量进行了测定，分析了土壤水分时空变异性，并探讨了土地利用（人工林地、自然草地和耕地）、坡位（上坡位、下坡位和沟床）和坡向（阴坡和阳坡）对土壤水变化的影响规律。【结果】（1）在时间上，土壤含水量变化受降水变化控制；在垂直空间上，上坡位和下坡位的样地随着土层深度的增加，其土壤含水量呈现先递减后稳定或先递减后递增的规律，土壤水分垂直变化分层大致按照速变层-活跃层-次活跃层-相对稳定层的顺序自上而下分布，而位于沟床位置的样地，其垂直变化规律性复杂多变；（2）不同土地利用类型的土壤含水量变异性较大，在上坡位，不同土地利用土壤含水量相对大小为自然草地＞耕地＞人工林地，这是由于不同土地利用类型的耗水量高低不同所导致的；而在沟床位置，土壤含水量相对大小为人工林地＞耕地＞自然草地，其可能的原因是人工林地地表高程最低且距离河道最近，其土壤水分还能受到河道径流和地下水的双重补给，土地利用对土壤水分的影响被地形条件的影响所掩盖；（3）在地形条件中，坡位对土壤含水量影响显著，自上坡位到下坡位到沟床土壤含水量大致呈递增趋势；阴坡的土壤水分条件均优于阳坡。【结论】在研究区未来的生态恢复过程中，适宜在土壤水分条件较好的下坡位、沟床以及阴坡位置种植耗水量较大的人工林地，而在上坡位和阳坡适宜采用自然恢复的生态恢复模式。 |
| 关键词: 土壤水分；土地利用；坡位；坡向；黄土区 |
| DOI： |
| 分类号:S157.1 |
| 基金项目: |
|
| Effects of Different Land Use and Topographic Conditions on Soil Moisture in Loess Area |
|
MaYunxiu,XiaLu,FanYi
|
|
1.Shanxi Agricultural University;2.Shanxi Fenhe Valley Management Co. , Ltd.
|
| Abstract: |
| 【Background and objective】 Soil moisture is an effective water source for plant growth in the semi-arid Loess Plateau of China. Characterizing the response of soil moisture to its dominant controling factors, such as land use and topography, is important for the sustainability of vegetation restoration in this region.【Method】The soil moisture content of 0-200 cm soil layer under different underlying surface conditions, located in the Loess area of Ningwu County, Shanxi Province, was measured by soil drilling method from July to September in 2020. The spatial and temporal variability of soil moisture was then analyzed and the effects of land use (artificial forest land, natural grassland and cultivated land) , slope position (uphill position, downhill position and gully bed) and slope direction (shady slope and sunny slope) on the change of soil water were also discussed. 【Result】(1) The temporal variation of soil moisture and precipitation was roughly consistent. With the increase of soil depth, the soil moisture contents decreased first and then stabilized or increased on the up-slope and down-slope plots, which obeyed the order of rapidly variable layer—active layer—subactive layer—relatively stable layer, However, the vertical variation regularity of the sample plots located in the gully bed was changeable. (2) The soil moisture contents of different land use types were variable. The soil moisture order of the sample plot located at the uphill position was: natural grassland > cultivated land > artificial forest in the up-slope position,
which was caused by the different water consumption of different vegetation types. However, the order of soil moisture content of the sample plot located at the gully bed position was: forest land > cultivated land > natural grassland. The possible reason was that the elevation of the artificial forest land was the lowest and the distance from the river was the nearest, so its soil water could be fed up by both the river runoff and the groundwater. It can be seen that the influence of land use on soil moisture was concealed by the influence of topography in the position of gully bed. (3) The soil moisture content increased from the uphill position to the downhill position to the gully bed, and the soil moisture condition of the shady slope was usually better than that of the sunny slope. 【Conclusion】In the future ecological restoration process of the study area, it is suitable to plant artificial forests with large water consumption at the downhill position, gully bed and shady slope, where the soil moisture condition is better, while the ecological restoration model of natural restoration is suitable for the uphill position and the sunny slope. |
| Key words: soil moisture; land use; slope position; slope direction; loess area. |
