项目名称： 冻融作用下侵蚀黑土耕层氮时空分异变化驱动机制研究

项目编号： No.41471228

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 地质学

项目作者： 张少良

作者单位： 东北农业大学

项目金额： 99万元

中文摘要： 冻融作用下土壤氮（N）的转化-运移过程，主要受土壤理化性质及微生物等因素的影响。黑土坡面土壤侵蚀严重，土壤理化性质的异质程度较高，秋末春初频繁的冻融交替势必导致坡面土壤N素时空分异格局变化。但冻融影响下的侵蚀黑土耕层N时空分异变化特征及驱动机制尚不明确。本研究利用野外调查、监测、稳定同位素示踪和室内培养等手段，结合经典统计学和地统计学等分析方法，兼顾农田秸秆管理方式和坡向变化，研究：（1）冻融前后耕层土壤N时空分异变化特征；（2）冻融期耕层土壤N时空分异变化的主要物理和微生物驱动过程；（3）冻融期剖面土壤N素的转化-运移过程；（4）构建基于主导因子的冻融驱动下耕层土壤N时空分异格局变化预报模型。预期的成果可为黑土区坡耕地精准施肥和减轻面源污染等提供理论依据和技术支撑。

中文关键词： 土壤侵蚀环境效应评价；土壤质量；元素迁移；土壤肥力；多尺度效应

英文摘要： The process of freeze-thaw is affected by soil structure, composition, moisture, temperature, and microorganism and so on, and influences the process of soil nitrogen (N) transformation-migration. The high heterogeneity of soil properties is caused by the serious soil erosion on the slope in the Mollisol region, and must lead to the change of the spatial pattern of the N in the freeze-thaw period. However, the mechanisms of freeze-thaw on the change of the N spatial heterogeneity is still not clear. In the study, slope aspects and crop straw managemnt will be compared, and the methods of field investigation, characters monitoring, isotopic tracing and inside incubator, combining with the traditional statistics and geostatistics at the slope scale, are employed to clarify (1) the characters change of the N spatial heterogeneity in the plough layer before and after the freeze-thaw process; (2) the driving process of physics and microorganism on the change of the spatial variance during the freeze-thaw period; (3) the process of N transformation and migration on soil profile during the freeze-thaw period; (4) the method to build the prediction model for slope scale based on the main driving factors. The results can provide the theory and technology for refining the precision fertilization and reducing non-point source pollution.

英文关键词： Evaluation of soil erosion environment;Soil quality;Nutrient migration;Soil fertility;Scale effect