DISSERTATION RESEARCH: Determining the drivers of annual methane emissions in temperate wetlands

湿地是最大的温室气体甲烷的天然来源。湿地中甲烷的产生可以由一系列碳基质提供燃料，包括最近从植物材料中提取的有机物和已在土壤中储存多年的有机物。新旧碳基质对甲烷排放的相对贡献没有得到很好的限制，但可能会影响湿地生态系统加速或减缓未来气候变化。 该项目将使用实地测量和受控实验室实验，以确定加州萨克拉门托三角洲湿地甲烷生产燃料碳源的季节性变化;该湿地以前是美国西部最大的淡水湿地区域。研究地点是高度季节性的温带湿地。自然梯度将用于探索甲烷动态的生态和气象驱动因素。这项研究将提供湿地环境中甲烷产生碳源季节变化的稀有和有价值的数据。这项工作还将在加州萨克拉门托-圣华金三角洲湿地恢复的更广泛背景下进行，该地区150年的土地排水导致了极端的地面沉降，非常大的温室气体排放以及一系列其他水文和生态问题。公共和私营机构将参与将该项目的科学成果转化为信息，供与三角洲未来有关的公共利益攸关方和机构使用。合作的一个具体成果将是协助制定湿地恢复议定书，以量化和尽量减少三角洲生态系统的甲烷排放。

Wetlands are the largest natural sources of the potent greenhouse gas methane. Production of methane in wetlands can be fueled by a range of carbon substrates, including organic matter recently derived from plant material and organic matter that has been stored in the soil for many years. The relative contributions of old and young carbon substrates to methane emissions are not well constrained but may impact whether wetland ecosystems accelerate or mitigate future climate changes. This project will use field measurements and controlled laboratory experiments to determine seasonal changes in the carbon sources that fuel methane production in a wetland in the Sacramento Delta, California; formerly the largest region of freshwater wetlands in the western United States. The study site is characteristic of highly seasonal temperate wetlands. Natural gradients will be used to explore ecological and meteorological drivers of methane dynamics.This research will provide rare and valuable data on seasonal variation of carbon sources for methane production in a wetland environment. The work will also take place in the broader context of wetland restoration in the Sacramento-San Joaquin Delta, California, where 150 years of land drainage has led to extreme land subsidence, very large greenhouse gas emissions, and a range of other hydrological and ecological issues. Public and private agencies will be engaged to translate the scientific results of this project into information for public stakeholders and agencies concerned with the future of the Delta. A specific outcome of collaboration will be to provide assistance with the development of a wetland restoration protocols to quantify and minimize methane emissions in delta ecosystems.