在宁夏六盘山外围半干旱区，土壤含水量是影响林木成活与生长的关键因子，需深入理解森林坡面不同坡位的土壤含水量对降雨量的响应差异。本文在宁夏六盘山叠叠沟小流域，选择一个华北落叶松人工林典型坡面，于2021年5—10月利用自动气象站和土壤水分仪连续监测降雨等气象条件和坡面土壤含水量变化，分析土壤含水量的坡位差异及对降雨量级的响应。观测期间总降水量为443.7 mm，虽然接近多年平均值，但夏季干旱严重。结果表明：（1） 土壤含水量存在明显的生长季内变化，整体表现为先降低后升高的趋势，8月最低（0.112 m³·m^-3）。（2） 土壤含水量存在明显的坡位差异，整体表现为：上坡[（0.191±0.044） m³·m^-3]>中坡[（0.158±0.045） m³·m^-3]>下坡[（0.146±0.034) m³·m^-3]，表明土壤含水量的坡位变化因处于干旱年，主要受植被蒸散耗水量大小的影响，而受坡面汇流影响不大。（3） 在同一降雨量级时，因受土壤孔隙度和持水能力、林下草本截持、优先流等的影响差异，中坡的土壤含水量对降雨量增加的响应最敏感，其次是上坡，下坡最不敏感。（4） 在本研究区，降雨以<10 mm的小降雨事件为主，7 mm是形成有效降雨的阈值，超过此阈值的降雨才有可能缓解0~20 cm土层土壤干旱和补给该层土壤水分。本研究有助于理解半干旱山区森林坡面的土壤含水量大小变化与分布特征，指导确定基于坡面土壤水分的植被承载力和进行林水综合管理。

In the semi-arid zone of the Liupan Mountains in Ningxia, soil water content is a key factor affecting the survival and growth of trees, and it is necessary to understand the differences in soil water content on different slope positions of forested slopes and their response to different rainfall amounts. For this purpose, a typical slope covered by Larix principis-rupprechtii plantations was selected in the small watershed of Diediegou in the Liupanshan Mountains. From May to October 2021, meteorological conditions (such as precipitation) and changes in soil water content on this slope were continuously monitored with automatic weather stations and soil moisture meters to analyze the differences in soil water content on the slopes and their response to the depth of individual rainfall events. The total precipitation depth during the monitoring period was 443.7 mm, which was close to the long-term annual average, but with severe drought in summer. The results showed the following: (1) The soil water content varied significantly within the growing season; the overall level first decreased and then increased, being the lowest in August (0.112 m³·m^-3). (2) There were clear differences in soil water content among slope positions, generally in the order upper slope [(0.191 ± 0.044) m³·m^-3] > middle slope [(0.158 ± 0.045) m³·m^-3] > lower slope [(0.146 ± 0.034) m³·m^-3]. This indicated that the main factor influencing the differences in soil water content along slope positions is the amount of evapotranspiration by forest/vegetation, rather than the redistribution of rainwater along the slope by slope runoff in this dry year. (3) To the same rainfall depth, the response of soil water content on the middle slope was the most sensitive, followed by that on the upper slope, and the lower slope was the least sensitive, owing to the integrated effects of soil porosity, water-holding capacity, and understory vegetation. (4) At the study site, rainfall was dominated by small rainfall events below 10 mm, with 7 mm representing the threshold for effective rainfall, above which the rainfall is likely to alleviate the soil dryness and recharge the soil moisture in the soil layer of 0-20 cm. The results of this study can aid understanding of the variation and spatial distribution of soil water content on forest slopes in semi-arid mountainous areas and help determine the water-carrying capacity of forest/vegetation and integrated