【摘要】 【目的】探讨黄土高原生态林耗水深度和深层耗水量，以明确黄土高原生态林的耗水规律。【方法】选取延安地区16年生的侧柏、沙棘和刺槐三种常见的黄土高原生态林种，以土钻法获取不同生态林和草地的土壤水分含量。首先基于年际的土壤水分含量确定生态林的土壤水分活跃层；其次，基于> 25 m深剖面的土壤水分数据来确定三种生态林的耗水深度和深层耗水量，并分析不同土层的耗水速率。【结果】依据年际土壤水分含量变化，2 m土层为该地区土壤水分活跃层。侧柏、沙棘和刺槐的最大耗水深度分别为12.0 m、12.2 m和23.2 m，其16年内耗水总量分别为304 mm、664 mm和1763 mm。刺槐的深层土壤耗水速率最大，为110 mm a^-1；其次为沙棘，为42 mm a^-1；最小为侧柏，为19mm a^-1。在2～10 m土层刺槐的耗水量仅占总耗水量的44%。【结论】探究黄土高原生态林的耗水量需要根据生态林物种的耗水特性选择合适取样土层深度。更多还原

【Abstract】 [Objective] It is important to clarify the water consumption pattern of ecological forests in Loess Plateau for water resources management. However, it is limited to the sampling depth, and there is a lack of research on the depth and amount of maximum water consumption for ecological forests. [Method] Three common ecological forest species of Loess Plateau, namely, 16-year-old Platycladus orientalis, Hippophae rhamnoides, and Robinia pseudoacacia in Yan’an, were selected. Soil water contents under different ecological forests and natural grassland were obtained by hand-made auger. Firstly, the active soil water layer of the ecological forests was determined based on the annual seasonal soil water content change. Secondly, the water consumption depth and amount of the three ecological forests were determined based on the soil water contents in the soil depth profile（ >25 m） compared with grassland. Finally, the rate of water consumption of ecological forests from different soil layers was analyzed. [Result]The active soil water layer was considered in 2 m depth through seasonal soil water changes in Yan’an area. The more water consumption depths were 12.0 m, 12.2 m and 23.2 m with the water consumption amounts of 269 mm, 664 mm and 1727 mm for Platycladus orientalis, Hippophae rhamnoides, and Robinia pseudoacacia, respectively. The deep soil water consumption rate of Robinia pseudoacacia was the highest, which was 108 mm yr^-1, followed by Hippophae rhamnoides(42 mm a^-1) and Platycladus orientalis(17 mm a^-1). The water consumption amount from the 2-10 m soil layer of Robinia pseudoacacia only accounted for 45% of the total water consumption. [Conclusion] We need to select the appropriate sampling depth of soil layer according to the water consumption characteristics of ecological forest species.更多还原