摘要
【目的】探究提高干旱区荒漠苜蓿农田滴灌水分利用效率的方法,制定适宜的节水灌溉制度。【方法】以苜蓿为研究对象,基于HYDRUS-1D模型设置4种灌溉水平(高强度大灌溉量(LH-I)、中强度大灌溉量(MH-I)、低强度中等灌溉量(SM-I)、无灌溉(CK))和5个0~20 cm土层初始土壤体积含水率梯度(4%、6%、8%、10%、12%,分别表示为S1、S2、S3、S4、S5),分析苜蓿根系土壤体积含水率降至土壤凋萎点的时间、峰值及维持在土壤凋萎点以上的时长,筛选0~20 cm土层不同土壤初始体积含水率下的最优灌溉水平。【结果】0~20 cm土层土壤体积含水率的变化对SM-I、CK灌溉水平具有显著影响;在无灌溉的情况下,体积含水率?10%的0~20 cm土层土壤会补给根系层水分;低含水率的0~20 cm土层土壤更有利于LH-I灌溉水平下的水分在根系层的留存,SM-I水平下根系层水分的留存时长与0~20cm土层土壤体积含水率呈正相关。LH-I灌溉水平下的深层土壤体积含水率峰值相比MH-I、SM-I、CK灌溉水平分别提高10.28%、27.91%、107.93%;MH-I灌溉水平下根系层土壤体积含水率维持在凋萎点之上的时长最久,平均为5.7 d。【结论】当0~20 cm土层土壤体积含水率≤4%时,可采用LH-I灌溉水平;当0~20 cm土层土壤体积含水率?4%时,MH-I灌溉水平为最优选择。
【Objective】Soil water is one of the most important abiotic factors influencing plant growth in arid areas.This paper aims to develop an optimal drip irrigation schedule for alfalfa production in desert farmlands in Northwestern China.【Method】The study was based on the HYDRUS-1D model.It compared four irrigation schedules:intensive irrigation(LH-I),moderate intensity irrigation(MH-I),and low intensity irrigation(SM-I).Without irrigation was the control(CK).Each irrigation schedule was associated with five initial volumetric water contents in the 0-20 cm soil layer:4%(S1),6%(S2),8%(S3),10%(S4)and 12%(S5).Overall,there were 20 combinations.In the simulation for each treatment,we“measured”the time for soil water in the root zone to reach the wilting point,as well as the soil water content at the wilting point.We also measured the time-period during which the soil water content in the root zone remained above the wilting point.These enabled us to find the optimal irrigation schedule.【Result】The effect of SM-I and CK on the above criteria was more sensitive to change in the initial soil water content in the top 0-20 cm of soil.The plant roots were able to take up water even without irrigation when the initial soil water content in the 0-20 cm of soil was greater than10%.When the initial soil water content was less than 20%,the majority of irrigated water in the LH-I treatment remained in the topsoil.With an appropriate initial moisture content,the topsoil had a positive effect on retaining the irrigation water from MH-I in the root zone.The retention time of water in the root zone was positively correlated with the topsoil water content in SM-I.The water content in the deep soil was greater in LH-I irrigation than in other treatments.Soil water content remained above the withering point for 5.7 days in MH-I,the longest among all treatments.【Conclusion】When initial volumetric water content in the 0-20 cm soil layer was less than 4%,LH-I was optimal,when the initial topsoil water content was higher than 4%,MH-I worked the best.
作者
苗庆远
米丽娜
覃兰玉
朱俊毅
卢琦
杨文斌
程一本
MIAO Qingyuan;MI Lina;QIN Lanyu;ZHU Junyi;LU Qi;YANG Wenbin;CHENG Yiben(Cultivation Base of State Key Laboratory of Northwest Land Degradation and Ecological Restoration of Ningxia University/Key Laboratory of Northwest Degraded Ecosystem Restoration and Reconstruction of the Ministry of Education,Yinchuan 750021,China;School of Soil and Water Conservation,Beijing Forestry University,Beijing 100091,China;China Academy of Forestry Sciences,Beijing 100091,China;Inner Mongolia Low Coverage Desertification Control Technology Development Co.,Ltd,Hohhot 010000,China)
出处
《灌溉排水学报》
CAS
CSCD
2024年第5期8-15,共8页
Journal of Irrigation and Drainage
基金
西北土地退化与生态恢复重点实验室(宁夏大学)开放基金(LDER2023Q05)
自然科学基金委重点项目—黄土区土壤—地表—地下水文多维耦合过程及植被调控机制(U214320030)
北京林业大学“北京市大学生科学研究与创业行动计划”(S202210022027/S202210022028)。
关键词
荒漠农田
紫花苜蓿
滴灌
含水率
灌溉制度
desert farmland
alfalfa
drip irrigation
moisture content
irrigation scheduling
