摘要
为研究宁南山区退耕还林区不同坡位土壤水分时空分布规律,利用定点取样和室内实验相结合的方法,研究了天然沙棘和人工油松两个典型坡面的上、中、下3个坡位0~100 cm土层土壤含水率的动态变化,分析其沿深度方向变化和季节动态情况。结果表明:天然沙棘和人工油松土壤含水率最高的坡位与土壤容重最小、孔隙度最大的坡位一致,分别为中坡位和下坡位;坡位对天然沙棘土壤含水率的影响层在20 cm以下,对人工油松的影响层在40 cm以下;土壤含水率随降雨量增加而增大,天然沙棘土壤含水率对于降雨量的响应较人工油松更敏感;相同降雨条件下天然沙棘土壤含水率增幅大于人工油松;在不同坡位土壤水分的时空分布上,沿深度方向天然沙棘各坡位土壤含水率在20 cm以下土层出现差异,人工油松在40 cm以下土层出现差异,当月降雨超过200 mm时,天然沙棘各坡位间土壤含水率的差异性减小,人工油松各坡位的差异性增大,这说明植被类型对土壤含水率的分布具有重要影响。
In order to investigate the spatial-temporal distribution of soil water in the reforestation hilly area of different slope positions in Southern Ningxia,the seasonal dynamics and vertical changes of soil water content in 0-100 cm soil layer at upper,middle,and lower slope positions of two typical slopes with natural forest of sea-buckthorn and artificial forest of pinus tabulaeformis were studied by in-situ field sampling and laboratory experiments. The results showed that the slope position with the highest soil water content was consistent with the slope position with the most favorable soil bulk density and pore conditions,which happened at the middle slope position of sea-buckthorn forest and the lower of pinus tabulaeformis forest. The slope position influenced the soil water content of natural sea-buckthorn forest below 20 cm soil depth,and below 40 cm to pinus tabulaeformis. Soil water content increased with the increase of rainfall,and the effect of rainfall on the soil water of natural forest was greater than that of artificial forest. Under the same rainfall condition,soil water content of natural sea-buckthorn forest increased more than that of artificial pinus tabulaeformis forest. The significant difference of soil water between slope positions occurred under 20 cm soil depth for natural sea-buckthorn forest,and under 40 cm soil depth for artificial pinus tabulaeformis forest. When the monthly rainfall exceeded 200 mm,the difference of soil moisture among slop positions reduced for natural sea-buckthorn forest but increased for artificial pinus tabulaeformis forest,which indicated that vegetation type had an important influence on the distribution of soil moisture content.
作者
陶吉杨
谭军利
魏童
郑飞龙
张维江
TAO Jiyang;TAN Juni;WEI Tong;ZHENG Feilong;ZHANG Weijiang(School of Ciwil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China;Engineering Research Center for Effcient Uilization of Modern Agriculural Water Resoures in Arid Regions,Ministry of Education,Yinchuan 750021,China;Engineering Technology Research Center of Water-saving Irigation and Water Resource Regulation in Ningxia,Yinchuan 750021,China)
出处
《水资源与水工程学报》
CSCD
2020年第4期216-222,共7页
Journal of Water Resources and Water Engineering
基金
宁夏回族自治区重点研发项目(2018BEG02010)
国家自然科学基金项目(51309135、31860590)
宁夏高等学校一流学科建设(水利工程)项目(NXYLXK2017A03)。
关键词
土壤含水率
时空分布
退耕林地
坡位
植被类型
宁南山区
soil water content
spatial and temporal distribution
reforestation land
slope position
vegetation type
hilly area of Southern Ningxia
