干旱灌区土壤水分和盐分时间稳定性特征及其改进分组预测  

Temporal stability characteristics of soil water and salt and the improved grouping prediction in arid irrigation areas

作　　者：孙贯芳 朱焱[2] 杨金忠[2] 屈忠义 李永红[1] 高照良[1] SUN Guanfang;ZHU Yan;YANG Jinzhong;QU Zhongyi;LI Yonghong;GAO Zhaoliang(Institute of Soil and Water Conservation,Northwest A&F University,Yangling 712100,China;State Key Laboratory of Water Resources Engineering and Management,Wuhan University,Wuhan 430072,China;School of Energy and Environment,Inner Mongolia University of Science and Technology,Baotou 014010,China)

机构地区：[1]西北农林科技大学水土保持研究所,杨凌712100 [2]武汉大学水资源工程与调度全国重点实验室,武汉430072 [3]内蒙古科技大学能源与环境学院,包头014010

出　　处：《生态学报》2024年第20期9314-9328,共15页Acta Ecologica Sinica

基　　金：国家重点研发计划项目(2023YFD2001404);国家自然科学基金(42307449,52179041);内蒙古自治区科技成果转化专项资金(2021CG0022)。

摘　　要：干旱灌区土壤水分及盐分的时空变异性强,时间稳定点的判断对区域水盐监测评估及预测具有重要意义。然而,当前尚不清楚干旱灌区土壤水分和盐分时间稳定性特征及均值预测效果。为此,以内蒙古河套灌区隆胜研究区大量的水盐观测数据为基础,在分析区域土壤水盐时间稳定性特征及其差异的基础上,提出改进分组时间稳定性分析方法,并验证了其预测效果。结果表明,土壤水分含量越小,变异性越大,而土壤盐分均值越大,变异性越大。相应地,土壤盐分平均相对偏差(MRD)和平均相对偏差的标准差SDRD的关系完全不同于土壤水分,土壤盐分的MRD越小,SDRD也越小,并非MRD接近于0的点SDRD小。这导致用最小SDRD、最小时间稳定性指数ITS或者多个SDRD较小的相对时间稳定性点估算区域土壤水分均值取得较好的结果(R^(2)均超过0.96),而估算区域土壤盐分则有较大偏差(R^(2)为0.49—0.78)。将土壤水盐数据分成若干组,在组内分别进行时间稳定性分析,该改进时间稳定分析对区域土壤水分的预测效果并未提高,但大幅提高土壤盐分预测效果,R^(2)达到了0.90以上。以改进分组时间稳定性分析方法形成的土壤盐碱化长期监测点,兼顾了不同盐渍化水平盐分的变化过程,有利于了解不同盐渍化土壤在时间和空间上的演化过程。The spatial and temporal variability of soil water and salt in arid irrigation area is strong.A large number of observation data is often required to monitor,evaluate and predict regional water and salt dynamics.Thus,the selection of temporal stability location is of great significance to the long-term water and salt observations.However,the applicability of the temporal stability analysis methods to soil salinity in irrigated areas,and the similarities and differences of the temporal stability in soil water and salt,as well as the prediction effect of regional salt average with temporal stability analysis are still unclear.Therefore,based on a large number of water and salt observation data in Longsheng study area of Hetao Irrigation District in the Inner Mongolia,the temporal stability feature of regional soil salinity,and their similarities and differences compared with the temporal stability of soil water were analyzed.Then,an improved grouping temporal stability analysis method was proposed,and the prediction effect of this method on regional soil water and salt were verified.The results showed that the lower soil moisture content was with the greater variability,while the higher mean soil salinity was with the greater variability.This was because the heterogeneity of groundwater status and vegetation distribution in spatial location intensified the variation of soil moisture content when soil water decreased gradually.However,for soil salinity,soil salt leaching was mainly affected by soil texture and its own salt content when salt was washed out by sufficient irrigation or rainfall in the whole region.While the process of soil salt accumulation was affected by groundwater conditions,crop types,and so on.The spatial variability of influencing factors in the salt accumulation intensified the variation of soil salinity.Accordingly,the relationship between mean relative deviation(MRD)and standard deviation of the mean relative deviation(SDRD)of soil salt was completely different from that of soil water.The sma

关 键 词：土壤水分 土壤盐分 河套灌区 时间稳定性分析 时空变异 

分 类 号：S156.41[农业科学—土壤学]