中国南方地区氮沉降对稻田甲烷排放影响的遥感监测与模拟

项目名称： 中国南方地区氮沉降对稻田甲烷排放影响的遥感监测与模拟

项目编号： No.41471343

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 张秀英

作者单位： 南京大学

项目金额： 84万元

中文摘要： 氮沉降已经成为全球面临的重大环境问题之一，探讨区域尺度氮沉降对稻田排放甲烷（CH4）的影响对于全球变化研究和计算全球CH4收支平衡具有重要意义。本研究选择我国南方水稻种植区，首先利用卫星遥感监测的大气NO2柱浓度，耦合大气化学传输模型模拟的硝态氮和铵态氮廓线，并结合地基监测，根据干湿沉降模型模拟氮沉降的时空分布格局；布置受控实验，监测不同氮沉降组分和沉降量对稻田排放CH4的影响，建立定量影响模型，同时布置野外监测点，修正建立的影响模型；利用MODIS影像及其产品，提取水稻种植面积、轮作、水淹等信息；并根据氮沉降及稻田、土壤等的时空分布格局，利用生物地球化学模型模拟区域尺度氮沉降对稻田排放CH4的影响，从而揭示中国南方地区氮沉降影响稻田CH4排放的时空动态和驱动过程。该研究对遥感技术应用向定量化方向发展、全球变化研究具有重要意义，为国家相关部门制定适应性政策提供科学依据。

中文关键词： 氮沉降；甲烷；稻田；遥感；大气化学传输模型

英文摘要： Nitrogen deposition is one of the global environmental problems, inducing serious impact on ecosystems. However, the influence of nitrogen deposition on CH4 emissions from paddy field at regional scale is rarely studied. Taking the south area of China as the study area, this proposal firstly inverses the temporal and spatial variations of nitrogen deposition by fusing the profiles of NH4-N and NO3-N from the simulation of atmospheric chemistry model, NO2 column concentrations from satellite observation, and the wet and dry nitrogen depositions from ground observations. Second, controlled experiments are conducted to monitor the characteristics of CH4 emissions and the physical characteristics of soil from paddy field under the influence of different nitrogen compositions and amounts, and then the influencing model of CH4 by nitrogen deposition are constructed. At the same time, several fields are selected based on the spatial and temporal gradients of nitrogen deposition in the study area, and relevant soil parameters are measured to revise the influencing model based on the controlled experiments. Third, the spatial distribution, planting, rotation of paddy field in south area of China are obtained from MODIS. Based on the spatial distribution of nitrogen and paddy field, a process-model of nitrogen cycling is used to reveal the mechanism of the influence of nitrogen deposition on CH4 emissions at regional scale. This study has important theoretical and practical significance to the development of quantitative, fine direction in remote sensing applications, and to improve the estimation accuracy of the global CH4 emissions. Moreover, it also provides the scientific basis for the relevant departments to make adaptation policies.

英文关键词： Nitrogen deposition;Methane;Paddy field;Remote sensing;Atmospheric chemical transport model