红壤坡耕地氮素输移形态对土壤水文过程响应及机理

项目名称： 红壤坡耕地氮素输移形态对土壤水文过程响应及机理

项目编号： No.41501300

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 地质学

项目作者： 莫明浩

作者单位： 江西省水土保持科学研究院

项目金额： 20万元

中文摘要： 降雨侵蚀造成的坡耕地氮素流失不仅导致土地生产力下降，而且成为非点源污染的来源，氮素形态对作物生长和水体污染都有重要作用，而氮素的输移形态受土壤水文过程影响，地表径流、水分入渗和土壤水分含量影响氮素含量及形态特征，目前相关研究尚不系统。本研究以典型红壤坡耕地为对象，以江西水土保持生态科技园为野外试验基地，利用大型土壤渗漏装置，采用野外观测与模拟试验相结合的方法，明确降雨条件下红壤坡耕地地表径流、壤中流和地下径流的分层输移过程中氮素的形态特征规律；通过对土壤水文过程中硝态氮、铵态氮、有机氮等不同形态氮素的测定，研究氮素输移的形态特征，采用数理统计方法，建立氮素含量与径流和土壤含水量之间的关系，揭示氮素输移形态对土壤水文过程响应及机理，阐明草被覆盖措施对氮素迁移的作用。研究结果将有助于深化红壤坡耕地氮素迁移机制的理解，为水土流失和非点源污染防治、发展坡耕地生态农业提供科学依据。

中文关键词： 水土流失；元素迁移；面源污染；红壤坡耕地；；土壤水文过程

英文摘要： Nitrogen loss associated with soil loss not only leads to land degradation, but also behaves as a source of non-point source pollution. Nitrogen forms play an important role on crop growth and water pollution, and forms of nitrogen movement affected by soil hydrological processes. Surface runoff, infiltration and soil moisture affect nitrogen content and forms characteristics. In this study, taking typical red soil slope land as the research object and taking Jiangxi Eco-science Park of Soil and Water Conservation, China as the field test site, using large scale drainage lysimeter, field observations and simulation methods are used to make clear of nitrogen hierarchical morphology moving law duing surface runoff, interflow and groundwater runoff under rainfall in red soil slope farmland. By testing different forms of nitrogen such as nitrate, ammonium, organic nitrogen during soil hydrological processes, nitrogen forms’ characteristics will be analyzed. Using mathematical statistical methods, relationships between nitrogen content with runoff and soil moisture will be built. Response and mechanism of nitrogen and its forms to soil hydrological processes will be revealed and the effects of measure covered with grass to nitrogen movement will be clarified. The results will help to deepen the understanding of the nitrogen movement mechanism in red soil slope farmland for soil erosion and provide a scientific basis for non-point source pollution control and development of ecological agriculture.

英文关键词： soil water erosion;elenment tracing;non-point pollution;red soil sloping farmland;soil hydrological processes