摘要
为揭示黄土高原南部塬区不同土地利用方式土壤水分时空变化特征,2014—2022年间采用土壤温湿度自动观测系统对苜蓿地、休闲地、高产农田、低产农田0—10 m剖面21层的土壤含水量进行了定位监测,并探究了其时空变化的影响因素。结果表明:4种土地利用方式中,由于多年生苜蓿地根系强吸水效应,其平均土壤含水量显著小于其他3种土地利用方式;随着土层深度的增加,苜蓿地土壤含水量先减小后增大,其他3种利用方式土壤含水量大致呈增大趋势;在季节变化特征上,土壤水分季节性干湿交替层分别为0—2 m、0—1 m、0—3 m、0—1 m,最小值和最大值分别出现在1—2月和9—11月;年尺度上,苜蓿地土壤含水量变异最大,高产农田次之,低产农田和休闲地变异性最小;就长期动态而言,土壤干层厚度和储水量变化与降水年际分布密切相关,2014—2022年各土地利用方式年均土壤储水量呈现增大趋势,2019、2021两丰水年份苜蓿地储水量增幅明显,降水补给深度可达4 m;相关性分析表明,土地利用方式、土层深度和黏粒含量为影响土壤含水量的关键因子。研究结果可为黄土高原深层剖面土壤水分观测和模拟提供数据支撑。
To reveal the spatial and temporal variation characteristics of soil water under different land use types in the southern tableland of the Loess Plateau,an automatic soil water observation system was used to monitor the soil water content(SWC)of 21 layers in 0—10 m profiles of alfalfa field,fallow field,fertilized cropland,and unfertilized cropland during 2014—2022.The spatial and temporal variation characteristics of the SWC and its influencing factors were explored.The results showed that the average SWC of alfalfa field was significantly lower than the other three land use types due to the strong water absorption effect of root system.With the increase of soil depth,the SWC of alfalfa field decreased first and then increased,while the SWC of the other three land use types showed an increasing trend.For the characteristics of seasonal variation,the seasonal dry-wet alternation soil layer of soil water were 0—2 m,0—1 m,0—3 m and 0—1 m,respectively,with the minimum and maximum data appearing in January to February and September to November,respectively.On an annual scale,SWC variability was the largest in alfalfa field,followed by that in fertilized cropland and in unfertilized cropland,while the fallow field was the smallest.In terms of long-term dynamics,the change of soil dry layer thickness was closely related to the interannual distribution of precipitation,the average annual soil water storage(SWS)of each land use types showed an increasing trend in the past 9 years,and the SWS increased significantly in the two water-abundant years of 2019 and 2021 in alfalfa field,where the recharge depth by precipitation infiltration could reach 4 m.Correlation analysis showed that land use,soil depth and clay content were the key factors influencing the SWC.The results can provide data for the observation and simulation of soil water in the deep soil profiles of the Loess Plateau.
作者
王中琦
汤晓迪
杜康
周玲
房凤如
韩晓阳
刘文兆
朱元骏
WANG Zhongqi;TANG Xiaodi;DU Kang;ZHOU Ling;FANG Fengru;HAN Xiaoyang;LIU Wenzhao;ZHU Yuanjun(College of Soil and Water Conservation Science and Engineering(Institute of Soil and Water Conservation),Northwest A&F University,Yangling 712100,China;Sericultural Research Institute,Chengde Medical University,Chengde 067000,China;Shaanxi Changwu National Field Observation and Research Station for Farmland Ecosystem,Changwu 713600,China)
出处
《生态学报》
CAS
CSCD
北大核心
2024年第20期9329-9341,共13页
Acta Ecologica Sinica
基金
国家自然科学基金项目(42007011,41971049,42377316)
中国科学院西部青年学者项目(XAB2018B08)。
关键词
土壤水分
土地利用方式
深层剖面
土壤干燥化
黄土高原
soil water content
land use type
deep soil profiles
soil desiccation
the Loess Plateau
