农牧交错带灌溉和旱作模式下马铃薯耗水差异

Difference of water utilization between irrigated and rainfed potato in the agro-pastoral ecotone of northern China

为揭示北方农牧交错带地区马铃薯“水改旱”种植对其产量和水分利用的影响,选取中国北方农牧交错带地区27个站点,基于站点的气象数据、土壤数据和管理数据驱动充分验证的APSIM-Potato模型,模拟分析农牧交错带地区灌溉和雨养马铃薯的耗水差异。结果表明:北方农牧交错带地区马铃薯种植连续灌溉10、20 a和30 a的产量分别为15900~35600、16400~34800 kg·hm^(-2)和16600~34800 kg·hm^(-2),改为旱作后对应的产量分别为12800~30600、13900~29100 kg·hm^(-2)和12700~25500 kg·hm^(-2);灌溉马铃薯产量均表现为西部较高,旱作马铃薯产量则为东部较高。连续灌溉10、20 a和30 a的播前1 m土层土壤含水量分别为163~388、161~394 mm和154~398 mm,改为旱作后分别下降31.8%、35.3%和36.9%。连续灌溉10、20 a和30 a后的地下水消耗量分别为5360~21330、8910~43680 m^(3)·hm^(-2)和19920~65770 m^(3)·hm^(-2),均为西部地下水消耗较高;改为旱作后,地下水恢复量分别为860、1445 m^(3)·hm^(-2)和1580 m^(3)·hm^(-2),均为东部较高。连续灌溉10、20 a和30 a的水分利用效率分别为54.8~94.6、54.7~93.2 kg·hm^(-2)·mm^(-1)和54.6~93.9 kg·hm^(-2)·mm^(-1),改为旱作后分别下降2.7%、1.1%和6.0%。本研究结果可为决策部门基于当地水资源现状调整马铃薯种植模式提供参考。

In order to reveal the impacts of“irrigated to rainfed”on potato yield and water utilization in the agro-pastoral ecotone of northern China,in this study,27 sites evenly distributed in the agro-pastoral ecotone of northern China were selected.A fully validated APSIM-Potato model driven by climate data,soil data and management data was used to simulate potato yield and water utilization under irrigated and rainfed conditions.Results showed that:potato yields ranged from 15900 to 35600 kg·hm 2,from 16400 to 34800 kg·hm^(-2) and from 16600 to 34800 kg·hm^(-2) under continuous irrigation of 10 years,20 years and 30 years in the agro-pastoral ecotone of northern China,and the corresponding yields were 12800~30600,13900~29100 kg·hm^(-2) and 12700~25500 kg·hm^(-2) under the rainfed condition.The irrigated potato yield was higher in the western agro-pastoral ecotone(APE),and the rainfed yield was higher in the eastern APE.Soil water content before planting were 163~388 mm,161~394 mm and 154~398 mm under continuous irrigation of 10 years,20 years and 30 years,and the values decreased by 31.8%,35.3%and 36.9%under rainfed condition.The groundwater consumptions were 5360~21330 m^(3)·hm^(-2),8910~43680 m^(3)·hm^(-2) and 19920~65770 m^(3)·hm^(-2) under continuous irrigation of 10 years,20 years and 30 years,and the consumption of groundwater was higher in the western APE.Under rainfed condition,the groundwater recoveries were 860,1445 m^(3)·hm^(-2) and 1580 m^(3)·hm^(-2),and the recovery was higher in the eastern APE.Water use efficiency of potato ranged from 54.8 to 94.6 kg·hm^(-2)·mm^(-1),from 54.7 to 93.2 kg·hm^(-2)·mm^(-1) and from 54.6 to 93.9 kg·hm^(-2)·mm^(-1) under continuous irrigation of 10 years,20 years and 30 years,and the values decreased by 2.7%,1.1%and 6.0%under rainfed condition.The results of our study can be helpful for decision-making departments to adjust potato planting pattern based on the local water resources condition.