黄土长武塬区苹果林地水量平衡研究

本研究以黄土高原沟壑区的典型代表长武塬为研究区,选取苹果园生态系统为研究对象,通过测定土壤蒸发、植物蒸腾、土壤含水量等水量平衡的各个组分,以月为时间尺度,分析初果园(9龄)和盛果园(19龄)林地系统的水量平衡状况,以期正确认识和评价黄土高原大面积种植苹果经济林的生态水文效应。结果表明:1)苹果林生态系统蒸散贡献量由小到大依次为冠层截留、土壤蒸发和果树蒸腾,初果园的土壤蒸发作用大于盛果园,而盛果园的蒸腾作用却大于初果园;2)土壤蒸发量及果树蒸腾量具有先增大后降低的趋势,土壤蒸发较果树蒸腾最大值出现提早一个月,土壤蒸发量6月份出现最大值,果树蒸腾最大值出现在7月;3)2014年盛果园、初果园5-8月总的平衡项分别为19.2 mm和-36.7 mm,占该时段降水量的7.9%和15.1%;2015年盛果园5-9月总平衡项为15.7 mm,占该时段降水量的4.3%,初果园5-9月的平衡项为-0.1 mm。研究结果可为黄土塬区农田、果园结构调整和土壤有限水资源的持续利用提供理论依据。

Study on soil water balance of apple orchards in the Loess Tableland of China

A typical tableland in the Loess Plateau, Changwu plateau, was selected to analyze the soil water balance of apple orchards by measuring various components of water budget such as soil evaporation, plant transpiration, and soil water content. The purpose was to understand and evaluate the eco-hydrological effect of extensive planting of the economic apple forest in the Loess Tableland. The results showed that: 1) the contribution to the evapotranspiration in the apple forestland ranked in the order of canopy interception