太湖流域丘陵区典型覆被类型土壤水中温室气体的溶解量与迁移研究

温室气体排放被认为是全球气候变化的重要驱动因素。近年来，土-气界面和水-气界面温室气体排放受到了很多研究关注，但是针对温室气体通过由陆地向水域输送这个关键环节的相关研究却十分缺乏。而土壤水正是该迁移的关键驱动力。太湖流域丘陵区植被繁茂、水热俱佳，因此其土壤水中溶解温室气体的溶解量和迁移不容忽视。在这个背景下，本项目选取典型覆被类型坡面，构建土壤水文与碳氮循环野外综合监测系统；定量揭示土壤水中温室气体（CO2，CH4和N2O）的溶解量及其迁移的时空变化过程与控制因子，构建土壤水中温室气体溶解量与环境因子之间的传递函数，并将其与土壤水文模型（Hydrus-3D）进行耦合，从而模拟土壤水中所溶解温室气体的迁移通量，并评估其在陆地生态系统温室气体排放中的重要性。项目研究将在揭示典型覆被类型土壤水中温室气体溶解与迁移的过程和机制，以及开发土壤水中所溶解温室气体的迁移模型等两个方面实现创新。

Greenhouse gas emissions have been recognized as critical driving factor of global climate change. Recently, traditional researches have investigated the greenhouse gas emissions at the soil-air interface and water-air interface. However, very few researches have pay attentions to the transport of greenhouse gases from upland ecosystem to aquatic ecosystem. Soil water movement is one of most important driving forces of this transport. In addition, with good vegetation cover, plenty of precipitation, and warm temperature, greenhouse gases dissolved in the soil water is un-negligible in Taihu Lake Basin, China. Therefore, in this proposal, we will select hillslopes with typical land covers in Taihu Lake Basin, and construct the monitoring systems of soil hydrology and C and N cycles on these hillslopes. Based on this, we will quantitatively reveal the spatio-temporal processes and controlling factors of storage and transport of greenhouse gases dissolved in the soil water, and develop transfer functions between the quantity of greenhouse gas dissolved in the soil water and environmental factors. These transfer functions will be coupled with Hydrus-3D to simulate the transport of greenhouse gases dissolved in the soil water and calculate their fluxes, and evaluate the ecological and environmental importance of greenhouse gases dissolved in the soil water. This project will be innovative in (1) revealing the mechanisms of storages and transports of greenhouse gases dissolved in the soil water under different land covers, and (2) developing methodologies in simulating the transports of greenhouse gases dissolved in the soil water.