摘要
以金沙江下游季节性干旱区紫色土坡耕地为研究对象,使用PR2/6土壤剖面水分测定仪和翻斗式雨量计对雨季0-100 cm土层的土壤含水量和降雨量进行连续观测,分析雨季紫色土土壤水分对降雨的响应。结果表明:每月平均土壤含水量之间存在显著差异,0-20 cm土壤含水率表现为9月>8月≈7月>6月,在整个雨季呈累加上升趋势。降雨量大小是影响土壤水分补给深度的决定因素。小雨(6.4 mm)只对10 cm土层土壤水分产生影响,平均提高12.35%;中雨(23 mm)对30 cm以上土层土壤水分产生影响,10,20,30 cm分别提高21.16%,17.77%,8.22%;大雨(49 mm)和暴雨(112 mm)均可影响60 cm以上土层土壤水分,49 mm提高7.18%~31.12%,112 mm提高34.12%~49.18%。0-40 cm土壤含水量增加量与降雨量和降雨历时在0.01水平上显著相关;0-20 cm土层土壤含水量增加量与前期干旱天数在0.05水平上显著负相关;30-40 cm土层土壤含水量增加量与3天前期累积降雨量呈显著相关。紫色土超过70%的土壤水分存储在60,100 cm土层中,分别占土壤总储水量的15.82%和58.39%。不同土层土壤储水量对降雨的响应规律不同,雨季初期6月0-30 cm表层土壤储水量变化最大,此时60-100 cm深层土壤储水量较为稳定,而7-9月深层土壤储水量变化幅度大于表层土壤。
Taking the purple soil sloping farmland in the seasonal arid area of the lower Jinsha river as the research object,the PR2/6 soil profile moisture analyzer and tipping rain gauge were used to continuously observe the soil moisture content of 0-100 cm soil layers and rainfall during the rainy season,and the purple soil moisture dynamics and its response to rainfall were analyzed.The results showed that there was a significant difference in the monthly average soil moisture content.The soil moisture content of 0-20 cm was as follows:September>August≈July>June,showing an increasing trend throughout the rainy season.The amount of rainfall was the major factor affecting the depth of water supply in soil.Light rain(6.4 mm)only affected soil moisture content above 10 cm,which increased 12.35%;moderate rain(23 mm)affected soil moisture content above 30 cm,and 10,20,and 30 cm increased by 21.16%,17.77%and 8.22%respectively;heavy rain(49 mm and 112 mm)affected soil moisture above 60 cm,49 mm increased by 7.18%~31.12%,112 mm increased by 34.12%~49.18%.The increased amount of soil moisture in 0-40 cm was significantly correlated with the amount of rainfall and rainfall duration at the level of 0.01;meanwhile,the increased amount of soil moisture in 0-20 cm soil layers was significantly negatively correlated with the drought interval at the level of 0.05;the increased amount of soil moisture in 30-40 cm was significantly correlated with the accumulated rainfall in the previous 3 days.More than 70%of the soil water of purple soil was stored in 60 cm and 100 cm soil layers,accounting for 15.82%and 58.39%of the total soil water storage,respectively.The respond of soil water storage in different soil layers to rainfall was different.The soil water storage of 0-30 cm changed the most in June,the soil water storage of 60-100 cm was relatively stable,while the soil water storage of 60-100 cm changed more than that of 0-30 cm from July to September.
作者
徐露
张丹
向宇国
陈凡
陈玉蓝
黄田钫
XU Lu;ZHANG Dan;XIANG Yuguo;CHEN Fan;CHEN Yulan;HUANG Tianfang(Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041;University of Chinese Academy of Sciences,Beijing 100049;Tobacco Company of Liangshan,Xichang,Sichuan 615000;Chengdu Institute of Biology,Chinese Academy of Sciences,Chengdou 610041)
出处
《水土保持学报》
CSCD
北大核心
2020年第6期37-45,共9页
Journal of Soil and Water Conservation
基金
中国烟草总公司四川省公司重点科技项目(SCYC201802)
四川省重点研发项目(2019YFG0332)。
关键词
降雨
土壤含水量
紫色土
季节性干旱区
rainfall
soil moisture content
purple soil
seasonal arid area
