土壤微域氧化还原电位空间异质性对土壤N2O汇的调控机制

项目名称： 土壤微域氧化还原电位空间异质性对土壤N2O汇的调控机制

项目编号： No.41301323

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 秦树平

作者单位： 中国科学院遗传与发育生物学研究所农业资源研究中心

项目金额： 24万元

中文摘要： 在前期工作中，我们通过连续多年田间观测发现：太行山低氮旱作农田土壤为显著的N2O汇。目前对干旱土壤N2O汇的调控机制还缺乏深入研究，这方面的研究可为农田土壤N2O排放通量的准确评估提供理论依据。本项目以太行山低山丘陵区旱作低氮农田为研究对象，以阐明土壤微域氧化还原电位（Eh）空间异质性对土壤N2O汇的调控机制为目标，依托中科院太行山实验站旱作雨养农田长期定位实验，利用Eh微电极探测系统，通过测定土壤半厌氧微域与厌氧微域的分布频度来表征土壤微域Eh空间异质性，重点研究土壤由湿变干过程中土壤微域Eh空间变异规律及其对土壤N2O通量的调控机制，为制定合理的农田管理措施、减少农田生态系统N2O排放提供理论依据。

中文关键词： 氧化亚氮；反硝化；硝酸盐；；

英文摘要： Previous multi-year field monitoring of soil N2O flux confirms that the rain-fed agricultral soil in the Taihang mountains is a significant sink of N2O. So far, there is few thorough studies focused on the regulating mechanisms of N2O sink in soils with low water content. The study on this aspect will provide theoretical basis for the accurate evaluation of N2O flux from agricultural soils. The purpose of the project is to illustrate the mechanisms of soil N2O sink regulated by Eh spatial heterogeneity in soil microzone. Based on the laboratorial control experiment and the long-term rain-fed agriculture field experiment, we will determine the frequencies of soil semi-anaerobic and anaerobic microzones to monitor the Eh spatial heterogeneity in soil microzone, using the miniaturized Eh probe system. We will focus on the dynamic pattern of soil microzone Eh during the conversion from wet to dry and its regulation on soil N2O flux. The results of the project will provide theoretical basis for establishing N2O mitigation strategies.

英文关键词： nitrous oxide；denitrification；nitrate；；