滨海盐渍农田土壤硝化势特征及其影响因素  

Characteristics and influencing factors of soil nitrification potential in coastal salinized farmland

作　　者：李红强 姚荣江[1] 杨劲松[1] 王相平[1] 谢文萍[1] 张新[1] LI Hong-qiang;YAO Rong-jiang;YANG Jing-song;WANG Xiang-ping;XIE Wen-ping;ZHANG Xin(State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院南京土壤研究所,土壤与农业可持续发展国家重点实验室,南京210008 [2]中国科学院大学,北京100049

出　　处：《应用生态学报》2022年第8期2205-2212,共8页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(42077084,U1906221,U1806215);国家重点研发计划项目(2019YFD1002702,2019YFD0900702)资助。

摘　　要：明确滨海盐渍农田土壤的硝化能力,探究土壤环境中影响硝化过程的主要因子,对调控农田土壤硝化作用和提高氮肥利用率具有重要意义。通过野外调查和室内分析相结合的方法,研究了滨海淤泥质滩涂盐渍区域(东营市和东台市)农田土壤硝化势和土壤物理、化学、生物学性质,运用多元逐步回归分析和结构方程模型(SEM)建立了土壤性质与土壤硝化势的相关关系。结果表明:滨海盐渍农田土壤除pH值较稳定外,其他土壤性质和土壤硝化势变化差异较大。土壤硝化势范围为0.04~10.42 mg·kg^(-1)·d^(-1),随土壤盐渍化程度增加而降低。相关分析表明,土壤硝化势与土壤有机质、阳离子交换量和Cl^(-)的相关性最强,相关系数分别为0.409、0.397和-0.337;而多元逐步回归分析表明,Na^(+)、粉粒、阳离子交换量、CO_(3)^(2-)+HCO_(3)^(-)为土壤硝化势的主要影响因子。SEM分析结果表明,Na^(+)、粉粒、阳离子交换量、CO_(3)^(2-)+HCO_(3)^(-)为影响土壤硝化势的直接因子,有机质、黏粒、Cl^(-)、SO_(4)^(2-)为影响土壤硝化势的间接因子。总之,土壤Na^(+)和阳离子交换量是影响硝化作用的两个主要因素,在该区域调控土壤NaCl含量和阳离子交换量为调节土壤硝化过程的有效手段。Understanding the nitrification capacity of coastal saline farmland soils and its main drivers is of great significance to regulate soil nitrification and improve the utilization efficiency of nitrogen fertilization in farmland.Using a combination of field investigations and laboratory analyses,we examined farmland soil nitrification potential and soil physical,chemical,and biological properties in the coastal muddy tidal flat saline soil area(Dongying and Dongtai).We established the correlation between soil properties and soil nitrification potential with multiple stepwise regression analyses and structural equation modeling(SEM).The results showed that soil pH value was relatively stable and other soil properties and soil nitrification potential varied in coastal saline farmland.The soil nitrification potential ranged from 0.04 to 10.42 mg·kg^(-1)·d^(-1)and decreased with the increases of soil salinization level.Soil nitrification potential had the strongest correlation with soil organic matter,cation exchange capacity,and Cl^(-),with the correlation coefficient being 0.409,0.397 and-0.337,respectively.The results of multiple stepwise regression analysis showed that Na^(+),silt,cation exchange capacity,and CO_(3)^(2-)+HCO_(3)^(-)were the main influencing factors of soil nitrification potential.The results from the SEM analysis suggested that Na^(+),silt,cation exchange capacity,and CO_(3)^(2-)+HCO_(3)^(-)directly affected soil nitrification potential,and soil organic matter,clay,Cl^(-)and SO_(4)^(2-)had indirect effects.In all,soil Na^(+)and cation exchange capacity were the two main factors affecting nitrification.Adjusting soil NaCl content and cation exchange capacity was an effective means of regulating soil nitrification.

关 键 词：硝化势 盐渍农田 结构方程模型 

分 类 号：S154.1[农业科学—土壤学]