半干旱草原型流域土壤水分变异及其影响因素分析  

Analysis of soil moisture variation and its influencing factors in semi-arid steppe watershed

作　　者：张璐[1] 朱仲元[1,2] 张圣微 王慧敏[1] Zhang Lu;Zhu Zhongyuan;Zhang Shengwei;Wang Huimin(College of Water Resources and Civil Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China;Key Laboratory of Water Resources Protection and Utilization of Inner Mongolia Autonomous Region,Hohhot 010018,China;Data Research Laboratory of Inner Mongolia Autonomous Region and Large Agricultural Applications,Hohhot 010018,China)

机构地区：[1]内蒙古农业大学水利与土木建筑工程学院,呼和浩特010018 [2]内蒙古自治区水资源保护与利用重点实验室,呼和浩特010018 [3]内蒙古自治区农牧业大数据研究与应用重点实验室,呼和浩特010018

出　　处：《农业工程学报》2020年第13期124-132,共9页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(51779116);地区科学基金项目(51669018,51869015);内蒙古自然科学基金杰出青年培育基金(2019JQ06);中国科学院“西部之光”青年学者计划。

摘　　要：土壤水分是岩石圈—生物圈—大气圈—水圈间水分循环的重要环节,是半干旱草原型流域植物生长的主要限制因子。该研究基于内蒙古锡林郭勒盟锡林河流域野外实测土壤水分数据,利用主成分分析和冗余分析等方法,对不同土壤类型垂直剖面土壤水分变化特征及其潜在环境影响因子进行了对比分析。结果表明,黑土、红砂土、栗钙土、盐土间土壤水分含量呈依次增大趋势;随着土层深度加深,土壤水分变异性减弱,且各层土壤水分变异性随时间变化受到土壤类型的影响较大;主成分分析表明海拔、植被高度和坡度等包含了解释土壤水分变异68.50%的信息;冗余分析识别出海拔和植被高度是土壤水分变异的关键潜在环境驱动因子。该研究可为半干旱草原型流域生态水文过程研究提供数据和理论支持。Soil moisture is an important part of the lithosphere-biosphere-atmosphere-hydrosphere,and which is the main limiting factor for plant growth in watersheds of the semi-arid steppe as well.This study aimed to explore the characteristics of soil moisture variation and its potential environmental impact factors.This study had a significant effect on maintaining steppe ecosystem health,such as promoted the understanding of the eco-hydrological cycle of grassland and degraded grassland restoration.The Xilin River Basin located in the middle east of Inner Mongolia was chosen as the study area.The experiments had been performed in May 2019.Two meters of soil moisture detection tube was buried at each sampling point after removing the ground cover and floating soil.Besides,the soil moisture measurement depth was set from 0 cm to 180 cm.Soil moisture data were observed by using the Time Domain Reflectometry(TDR)at 55 sampling points from July 22 to October 20 in 2019 after the soil layer was stabilized.Three replications were performed at each sample point.Such a soil survey was conducted within 3 days by twice a month in July and August,and once a month in the remaining months.Meanwhile,vegetation investigations were executed once a month,including vegetation height,vegetation coverage,and aboveground biomass.Besides,3 original soil samples were brought back from the field for calibrating the TDR in the laboratory.It was indicated that the TDR was reliable with guaranteed that the soil moisture data used in the calibration formula was ranged from saturation to dryness completely.Based on the observed soil moisture and affiliated data in the field the characteristics of soil moisture changed in the vertical profiles,as well as its potential environmental impact factors were analyzed and compared among 4 soil types by using Principal Component Analysis(PCA)and Redundancy Analysis(RDA).The results indicated that the soil moisture in the Xilin River Basin was low overall.The changes in soil moisture at different soil depths

关 键 词：土壤 干旱 水分 草原 锡林河流域 

分 类 号：S152.7[农业科学—土壤学]