河套平原盐渍化地区非饱和带氮的分布特征及影响因素  

Distribution Characteristics and Influencing Factors of Nitrogen in Unsaturated Zone in Salinized Area of Hetao Plain

作　　者：高爽 苏春利[1] 谢先军[1] 陶彦臻 曾邯斌 潘洪捷[2] 闫福贵[2] Gao Shuang;Su Chunli;Xie Xianjun;Tao Yanzhen;Zeng Hanbin;Pan Hongjie;Yan Fugui(School of Environmental Studies,China University of Geosciences,Wuhan 430078,China;Geological Survey Institute of Inner Mongolia Autonomous Region,Huhhot 011020,China)

机构地区：[1]中国地质大学环境学院,湖北武汉430078 [2]内蒙古自治区地质调查院,内蒙古呼和浩特011020

出　　处：《地球科学》2022年第2期568-576,共9页Earth Science

基　　金：内蒙古自治区河套灌区盐碱地生物修复与综合开发研究(No.2019046338)。

摘　　要：土壤氮在植物生长、土壤理化性质和微生物活动中扮演着重要的角色.为了识别盐渍化地区非饱和带氮的迁移过程,以河套灌区典型盐渍化耕地为例,通过非饱和带监测和水化学统计分析,探究了土壤剖面中氮素分布的差异性及主要影响因素.结果表明,研究区0~100 cm土层深度土壤氮含量处于较低水平,NO_(3)‐N、NH_(4)‐N和NO_(2)‐N含量平均值分别为4.88、1.63和0.04 mg/kg.土壤氮的空间分布与土层深度和理化性质有关,随深度增大,NO_(3)‐N含量呈逐渐增加的趋势,高值区主要分布于40~80 cm深度的土层,NH_(4)‐N含量多集中在60~100 cm深度的土层.土壤NO_(3)‐N含量主要与土壤p H、含水率和水溶性盐分含量(TDS、Cl-、SO_(4)^(2-)、Na^(+))有关,而NH_(4)‐N含量主要受含水率、黏粒和TOC含量的影响.NO_(3)‐N和NH_(4)‐N在土壤中的积累与水盐运移、土壤矿物的静电吸附和微生物的控制有关,这在很大程度上受土壤粒度组成、p H、有机质含量和竞争性阴、阳离子含量的影响.Soil nitrogen plays an important role in plant growth,soil physicochemical properties and microbial activities.In order to identify the process and mechanism of nitrogen migration in the unsaturated zone in salinized areas,a typical salinized farmland in Hetao irrigation areawas selected to explore the difference of nitrogen distribution in soil profiles and the main influencing factors through monitoring the unsaturated zone and hydrochemical statistical analysis.The results showed that the soil nitrogen content in the 0-100 cm depth of the study area was at a low level,and the average contents of NO_(3)‐N,NH_(4)‐N and NO_(2)‐N were 4.88,1.63and 0.04 mg/kg,respectively.The spatial distribution of soil nitrogen is related to soil depth and physical and chemical properties.With the increase of soil depth,NO_(3)‐N content showed a trend of gradual increase.The high value area is mainly distributed in the soil layer with a depth of 40-80 cm,and the content of NH_(4)‐N mostly concentrates in the soil layer with a depth of 60-100 cm.Soil NO_(3)‐N content is mainly related to soil p H,water content and water‐soluble salt content(TDS,Cl^(-),SO_(4)^(2-)、Na^(+)),while NH_(4)‐N content is mainly affected by water content,clay particles and TOC content.The accumulation of NO_(3)‐N and NH_(4)‐N in soil is related to the movement of water and salt,the electrostatic adsorption of soil minerals and the control of microorganisms,which are largely affected by soil particle size composition,p H,organic matter content and competitive anionsand cations content.

关 键 词：非饱和带 氮 盐渍化 TOC 土壤粒度 环境地质 

分 类 号：S153.61[农业科学—土壤学]