摘要
【目的】田间土壤水分状况是灌溉管理的基础,土壤水分的动态变化过程是灌溉预报的重要依据。【方法】通过监测冬小麦田间不同深度土壤含水量和气象数据,分析了小麦生育期内田间土壤水分动态变化过程及其对降水和作物需水量的响应情况,采用土壤水量平衡模型对土壤含水量变化过程进行模拟。【结果】小麦全生育期内,根系主要活动层(0~50 cm)中各层土壤含水量为12.00%~34.53%,方差为5.74~34.05。20 cm土壤含水量与冬小麦根系主要活动层(0~50 cm)土壤含水量相关性最好,相关系数为0.96。20和40 cm深度土壤含水量对降水和作物需水量的响应存在12 h滞后。拔节期后冬小麦田发生轻旱和中旱。旬尺度内,土壤水量平衡模型模拟最大误差小于10%。【结论】在降水和作物需水量共同影响下,土壤深度对土壤含水量变化过程存在影响,且随深度的增加影响减弱;20 cm深度土壤水分与根系主要活动层土壤水分变化过程最接近,可作为土壤水分监测的代表深度;在降水频率P=25%的水文年型下,冬小麦田需要进行补充灌溉,小于1旬时间尺度的水量平衡模型可很好的模拟土壤水分动态变化过程。
[Purpose]The soil moisture status in the field is the basis of irrigation management, and the dynamic process of soil moisture is an important basis for irrigation forecasting.[Method]By monitoring the soil moisture at different depths and meteorological data during the growth period of winter wheat, the dynamic process of soil moisture in the field of wheat growth and its response to precipitation and crop water requirement were analyzed, and the soil water balance model was used to simulate the change process of soil moisture.[Result]During the whole growth period of wheat, the soil moisture of each layer in the main active layer(0-50 cm) was between 12.00% and 34.53%, and the variance was between 5.74 and 34.05. The soil moisture of 20 cm was the best correlation with the soil moisture of the main active layer(0-50 cm) of winter wheat, and the correlation coefficient was0.96%. The response of soil moisture at 20 and 40 cm depth to precipitation and crop water requirement had a 12-hour lag. Light and moderate drought occurred in winter wheat fields after jointing stage. In the tenth scale, the maximum simulation error of the soil water balance model was less than10%.[Conclusion]Under the influence of precipitation and crop water requirement, soil depth had an effect on the change process of soil moisture, and the effect decreases with the increase of depth.The soil moisture at 20 cm depth was the closest to the change process of soil moisture in the main active layer of the root system, which can be used as the representative depth of soil moisture monitoring. In the P=25% hydrological year, supplementary irrigation is needed for winter wheat fields. The water balance model with less than one-tenth time scale can well simulate the dynamic process of soil moisture.
作者
杨荣赞
王龙
余航
刘艳阳
丁艳萍
赵文义
YANG Rongzan;WANG Long;YU Hang;LIU Yanyang;DING Yanping;ZHAO Wenyi(College of Water Conservancy,Yunnan Agricultural University,Kunming 650201,China;Soil and Fertilizer Workstation of Malong District,Qujing City,Malong 655100,China)
出处
《云南农业大学学报（自然科学版）》
CSCD
北大核心
2020年第4期717-725,共9页
Journal of Yunnan Agricultural University:Natural Science
基金
国家自然科学基金项目(51669035)
云南省应用基础研究计划项目(2015FD021)。
关键词
冬小麦
土壤水分
作物需水量
降水
土壤水量平衡
winter wheat
soil moisture
crop water requirement
precipitation
soil water balance
