盐渍化土壤剖面盐分与养分分布特征及盐分迁移估算  

Distribution Characteristics of Salinity and Nutrients in Salinized Soil Profile and Estimation of Salt Migration

作　　者：窦旭 史海滨[1,2] 李瑞平 苗庆丰[1,2] 田峰 于丹丹[1,2] DOU Xu;SHI Haibin;LI Ruiping;MIAO Qingfeng;TIAN Feng;YU Dandan(College of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Huhhot 010018,China;High Efficiency Water-saving Technology and Equipment and Soil Water Environment Engineering Research Center of Inner Mongolia Autonomous Region,Huhhot 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]高效节水技术装备与水土环境效应内蒙古工程研究中心,呼和浩特010018

出　　处：《农业机械学报》2022年第1期279-290,330,共13页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(51879132、51769024);内蒙古科技重大专项(zdzx2018059);内蒙古水利科技重大专项(nsk2018-M5)。

摘　　要：针对盐渍化灌区土壤盐渍化问题,以内蒙古河套灌区下游乌拉特灌域为研究区,通过野外实测与室内试验分析结合,采用冗余分析法探讨了盐渍化改良耕地与荒地春季(4月)和秋季(10月)根层土壤(0~20 cm、20~40 cm)盐分离子与全盐、pH值、养分之间的相关关系,明确了其变化特征与数量关系,并估算了试验区改良耕地和荒地间1 m土体的盐分迁移量。结果表明,改良耕地与荒地土壤阴离子均以Cl^(-)为主,分别占阴离子总量的45.27%、58.78%,阳离子以Na^(+)为主,分别占阳离子总量的60.67%、53.94%。荒地平均全盐含量超过7.0 g/kg,土壤盐渍化程度较重。冗余分析表明,改良耕地土壤全盐含量起主导作用的是SO_(4)^(2-)、Cl^(-)、Ca^(2+),荒地土壤全盐含量起主导作用的是Cl^(-)、Mg^(2+)、Na^(+)。土壤pH值变化与HCO_(3)^(-)有着密切的关系。改良耕地有效磷与Na^(+)呈显著负相关(P<0.05),荒地速效钾与K^(+)呈显著正相关(P<0.05),有效磷与Na^(+)显著负相关(P<0.05);在前2个排序轴中,改良耕地研究对象与环境关系的变量累积百分比分别为71.38%、71.65%,荒地研究对象与环境关系的变量累积百分比分别为89.02%、89.16%,反映出改良耕地与荒地各自的研究对象与环境变量之间的线性关系。改良耕地中Na^(+)对全盐、pH值、土壤养分的影响最大,其次是Ca^(2+);荒地中Na^(+)对全盐、pH值、土壤养分的影响最大,其次是K+。在作物一个生育周期内,荒地1 m土体中积盐量939842 kg/hm^(2)。地下水补给将盐分带到土壤中,占盐分积累量的70.06%,灌溉期改良耕地地下水迁移给荒地的盐分集中在60~100 cm土体中,占积盐量的22.83%,改良耕地水平渗透给荒地的盐量占积盐量7.11%。Aiming at the problem of soil salinization in salinized irrigation areas,taking Wulate Irrigation Area in the lower reaches of the Hetao Irrigation District,Inner Mongolia as the research area,through the combination of field test and indoor test analysis,the redundancy analysis method was used to explore the correlation between salt segregation elements and total salt,pH value,and nutrients in the root layer soil(0~20 cm,20~40 cm)in spring and autumn on the salinized improved cultivated land and wasteland,and its change characteristics and quantitative relationship were clarified,and the salt migration of 1m soil between the improved cultivated land and the wasteland in the experimental area was estimated.The results showed that the anions of the improved farmland and wasteland soil were mainly Cl^(-),accounting for 45.27%and 58.78%of the total anions,respectively,and the cations were mainly Na^(+),accounting for 60.67%and 53.94%of the total cations respectively.The total salt content of wasteland exceeded 7.0 g/kg on average,and the degree of soil salinization was relatively serious.Redundancy analysis showed that SO_(4)^(2-),Cl^(-)and Ca^(2+)played the leading role in improving the total salt content of cultivated soil,and Cl^(-),Mg^(2+)and Na^(+)played the leading role in the total salt content of wasteland soil.The change of soil pH value was mainly related to HCO_(3)^(-).Improved cultivated land had a significant negative correlation between available phosphorus and Na^(+)(P<0.05),wasteland available potassium had a significant positive correlation with K^(+)(P<0.05),and available phosphorus had a significant negative correlation with Na^(+)(P<0.05).In the first two ranking axes,the cumulative proportion of changes in the relationship between the cultivated land research object and the environment was 71.38%and 71.65%,respectively.The cumulative proportions of changes in the relationship between wasteland research objects and the environment were 89.02%and 89.16%,respectively,reflecting the linear relations

关 键 词：盐渍化灌区 盐分离子 养分 盐分迁移 相关关系 冗余分析 

分 类 号：S287[农业科学—农业水土工程]