干旱绿洲区储水灌溉与冻融过程对土壤呼吸的影响  

Effects of storage irrigation and freeze-thaw on soil respiration in an arid oasis area

作　　者：高雅玉 张新民[2] 李泽霞 宋玉 黄枭 何文博 GAO Yayu;ZHANG Xinmin;LI Zexia;SONG Yu;HUANG Xiao;HE Wenbo(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Gansu Provincial Water Science Research Institute,Lanzhou 730000,China;Gansu Institute of Soil&Water Conservation Sciences,Lanzhou 730020,China)

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050 [2]甘肃省水利科学研究院,甘肃兰州730000 [3]甘肃省水土保持科学研究所,甘肃兰州730020

出　　处：《甘肃农业大学学报》2023年第1期182-192,共11页Journal of Gansu Agricultural University

基　　金：甘肃省重点研发计划项目(22YF7FA165,18YF1NA031);高端外国专家引进计划项目(22JR10KA006);甘肃省重点人才计划项目(甘组通字[2019]39号);甘肃省水利科学试验研究及推广计划项目(甘水建管发[2022]59号、[2021]71号);甘肃省省级水资源费项目(甘水资源发[2021]105号)。

摘　　要：【目的】干旱绿洲区储水灌溉过程中存在着定额大、灌溉水利用效率不高、无效蒸发大和难以大面积推广应用等问题,也是造成绿洲区农业水资源紧缺的主要原因。为彻底改变这种现象并从机理角度探究储水灌溉和季节性冻融循环对干旱区绿洲土壤呼吸的影响。【方法】按照1200 m^(3)/hm^(2)的低灌溉定额分为灌水和非灌水处理,将冻融循环分为冻结期、冻融期和解冻期3个时间段,采用LI-8100土壤碳通量全自动测量系统对不同处理的土壤呼吸速率进行观测与分析。【结果】储水灌溉在冻融循环作用下会促使干旱绿洲区农田生态系统土壤呼吸速率增强,增加土壤的碳排放,改变干旱绿洲区农田生态系统的碳循环。【结论】在水分与季节性冻融循环叠加作用下,储水灌溉促使土壤呼吸速率随温度的波动更为剧烈。整个冻融过程中土壤呼吸速率呈现出解冻期大于冻结期大于冻融期的规律。不同土地利用方式土壤呼吸速率变化趋势一致,但对水分和温度的响应程度不同,土壤二氧化碳通量均值未灌水处理小麦地块的比玉米地块高出33.60%,灌水处理高出56.08%。冻结期、冻融期和解冻期3个时期土壤CO_(2)都表现为源。研究成果可为干旱绿洲区灌溉水资源高效利用和储水灌溉制度的制定提供理论基础与技术支撑。【Objective】In the process of storage irrigation in arid oasis areas,there were problems such as large quota,low irrigation water use efficiency,large ineffective evaporation and difficulty in large-scale application,which were the main reasons for the scarcity of agricultural water resources in the oasis area.In order to completely change the phenomenon and study the effects of storage irrigation and seasonal freezethaw cycles on soil respiration in arid oasis areas from a mechanism point of view.【Method】The LI-8100 automatic soil carbon flux measurement system was used to observe and analyze the soil respiration rate of each treatment,which was divided into irrigated and non-irrigated according to the low irrigation quota of 1200 m^(3)/hm^(2),and the freeze-thaw cycle was divided into three time periods:freezing period,freeze-thaw period and thawing period.【Result】Under the effects of freeze-thaw cycles,low rate storage irrigation will increase the soil respiration rate of farmland ecosystems,increase soil carbon emissions,alter the carbon cycle of farmland ecosystems,and benefit crop growth and improve food production in arid oasis areas.【Conclusion】Under the superimposed effect of moisture and seasonal freeze-thaw cycles,storage irrigation promotes greater fluctuations in soil respiration rate with temperature.Throughout the process,the soil respiration rate showed the law that the thawing period was greater than the freezing period and greater than the freeze-thaw period.The trend of change in soil respiration rate of different land use patterns was the same,but the degree of response to moisture and temperature was different.The mean soil carbon dioxide flux was 33.60%higher in the non-irrigated wheat plot than in the maize plot,and 56.08%higher in the irrigated treatment.Soil CO_(2) in the three periods of freezing,freeze-thawing and thawing were all identified as sources.The research results can provide theoretical basis and technical support for the formulation of storage irrigation schedu

关 键 词：土壤呼吸速率 储水灌溉 低定额 季节性冻融循环 干旱绿洲区 

分 类 号：S125.7[农业科学—农业基础科学]