阴山北麓地区降水特性和作物需水耦合关系分析——以武川县为例

Analysis of the coupling relationship between precipitation characteristics and crop water demand in the northern area of Yinshan Mountain—Taking Wuchuan County as an example

【目的】为旱作农业区提高水资源利用效率及配套农艺措施提供依据。【方法】以内蒙古阴山北麓地区武川县2000—2019年逐日气象资料为基础,分析了该地区马铃薯、春小麦2种作物在各生育时期的需水特征及作物需水和降水耦合情况。【结果】马铃薯、春小麦全生育期需水量分别为337.70和315.30 mm;马铃薯在块茎膨大期需水量最大,占全生育期需水量的32.17%;春小麦在拔节期、抽穗期需水量较大,分别占全生育期需水量的25.56%和21.28%;马铃薯、春小麦在全生育期需水量大于同期有效降水量;在作物主要生育时期,马铃薯和春小麦需水和降水的耦合度λ<1,降水无法满足作物需水量;春小麦需水与降水的耦合度与月份表现出良好的3次多项式关系,拟合程度较高,决定系数(R2)为0.9343。【结论】阴山北麓地区因降水结构和降水有效性不足造成与作物主要生育时期需水量耦合度低,即无法满足作物关键生育时期对水资源的需求,并从理论和实践两方面探索解决旱作农业区作物生产需水与降水的平衡关系。

【Objective】To provides a basis for improving water resource utilization efficiency and supporting related agronomic measures in dry farming areas.【Methods】Based on the daily meteorological data of Wuchuan County in the northern area of Yinshan Mountain of Inner Mongolia from 2000 to 2019,the water demand characteristics of potato and spring wheat in each growth period and the coupling conditions of water demand and precipitation of crops were analyzed.【Results】The water requirements for potato and spring wheat during the whole growth period were 337.70 and 315.30 mm,respectively.The water demand of potato during tuber expansion was the largest,accounting for 32.17%of the total water demand during the whole growth period.The water requirements of spring wheat in jointing and heading stage were the largest,accounting for 25.56%and 21.28%of the water demand in the whole growth stage respectively.The water demand of potato and spring wheat during the whole growth period is greater than the effective precipitation in the same period.During the main growth period,if the coupling degree(λ)of water demand and precipitation between potato and spring wheat wasλ<1,precipitation cannot meet the water demand of crops.The coupling degree of spring wheat water demand and precipitation showed a good third-degree polynomial relationship with month,with a high degree of fitting,and the determination coefficient(R2)was 0.9343.【Conclusion】In the northern area of Yinshan Mountain,due to precipitation structure and insufficient precipitation effectiveness,the coupling degree with the water demand in the main growth period of crops is low,that is,the demand for water resources in the key growth period of crops cannot be satisfied.This research explored the balance relationship between water demand and precipitation of crops production in dry farming agricultural areas from both theoretical and practical aspects.