Wen Hui-Xian, Zhao Xi-Ning, Gao Fei
Ministry of Education Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Northwest A＆F University, Yangling 712100, Shaanxi, China.
College of Water Resources and Architectural Engineering, Northwest A＆F University, Yangling 712100, Shaanxi, China.
Ying Yong Sheng Tai Xue Bao. 2022 Jul;33(7):1927-1936. doi: 10.13287/j.1001-9332.202207.030.
To clarify the desiccation effect of deep soil and water footprint of crop production in two typical dry-farming apple orchards on the Loess Plateau of China, with Luochuan County in semi-humid region and Mizhi County in semi-arid region as two typical apple planting areas, we used the WinEPIC model to quantitatively simulate and analyze the variations of soil moisture from 0 to 15 m and water footprint of apple production during 1980-2020. The results showed that annual yield of mature orchards in Luochuan and Mizhi followed an "S" curve, with the average annual values being 24.64 and 18.42 t·hm, respectively. The average annual evapotranspirations of Luochuan and Mizhi were 623.82 and 458.97 mm, the average annual drought stress days of Luochuan and Mizhi were 20.4 and 52.73 days, and the water overconsumption were 167.94 and 121.15 mm, respectively. The available soil water contents in Luochuan and Mizhi showed a sharp decline from 1 to 25 years old and from 1 to 23 years old, respectively, with average annual soil desiccation rates being 64.6 and 68.03 mm·a, respectively. The dry layer of deep soil for the orchards of Luochuan and Mizhi appeared at the 13th and 7th years, and would be stable after 23 and 22 years, respectively. The formation and stability time of the soil dry layer in the area with high precipita-tion was later than that with low precipitation. Long-term soil moisture deficit would result in irreversible soil dry layer. Water footprint of apple production in Luochuan and Mizhi were low in the early stage and high in the later stage, with the average annual values being 0.187 and 0.194 m·kg, respectively. Both apple yield and production water footprint were affected by precipitation. To ensure the sustainable and healthy development of apple industry, it was recommended that the optimal planting age of apple trees is about 23 years on the Loess Plateau where water sources is limited, and the maximum should not exceed 25 years.
为阐明中国黄土高原两个典型旱作苹果园深层土壤干燥化效应及作物生产的水足迹，以半湿润地区的洛川县和半干旱地区的米脂县作为两个典型苹果种植区，我们利用WinEPIC模型定量模拟和分析了1980—2020年0至15米土壤水分变化及苹果生产的水足迹。结果表明，洛川和米脂成熟果园的年产量呈“S”形曲线，年均值分别为24.64和18.42吨·公顷。洛川和米脂的年均蒸散量分别为623.82和458.97毫米，年均干旱胁迫天数分别为20.4和52.73天，水分超耗量分别为167.94和121.15毫米。洛川和米脂的土壤有效含水量分别在果园树龄1至25年和1至23年时急剧下降，年均土壤干燥化速率分别为64.6和68.03毫米·年。洛川和米脂果园深层土壤干层分别出现在第13年和第7年，分别在23年和22年后趋于稳定。高降水量地区土壤干层的形成和稳定时间晚于低降水量地区。长期土壤水分亏缺会导致不可逆的土壤干层。洛川和米脂苹果生产的水足迹前期低后期高，年均值分别为0.187和0.194立方米·千克。苹果产量和生产水足迹均受降水影响。为确保苹果产业可持续健康发展，建议在水源有限的黄土高原地区，苹果树最佳种植树龄约为23年，最长不超过25年。
