This paper summarises the results of an extensive field campaign which demonstrates that high sediment organic matter is the primary driver of methane ebullition in a sub-tropical, freshwater reservoir. Methane emissions from freshwater reservoirs represent an important global methane source. Whilst diffusive methane fluxes are commonly used for predicting total emissions, recent studies show that the under-reported ebullitive fluxes can vary by over three orders of magnitude within an individual system and have a greater relative contribution compared to diffusion. Key to predicting this variability in emission rates is to better understand the primary drivers of different emission pathways, and in particular ebullition. Zones of catchment derived organic material as well as elevated water column chlorophyll a concentration have been associated with increased rates of ebullition. Little Nerang Dam (LND), a subtropical freshwater reservoir in Queensland Australia, consistently experiences high rates of ebullition adjacent to major inflow arms that are both deposition zones of catchment organic material as well as areas with elevated water column chlorophyll a concentration. A year-long study of emission rates was undertaken on LND during which water column chlorophyll a concentration, bottom water temperature and sediment organic matter content were assessed for methane ebullition potential. This included a transect with high-spatial sampling (259 sites) from the dam wall to the ebullition zones to explore the relationship between water column chlorophyll a concentration, sediment organic matter content and methane ebullition. These results showed that ebullition was associated with the large forest litter deposits adjacent to major inflow sites where sediment organic matter content was significantly higher compared with the main body of the reservoir.

本文总结了一次广泛的野外研究的结果，该研究表明，高沉积物有机质是亚热带淡水水库甲烷甲烷沸腾的主要驱动力。淡水水库的甲烷排放量是全球重要的甲烷来源。尽管通常使用扩散甲烷通量来预测总排放量，但最近的研究表明，漏报的沸腾通量在单个系统中的变化可能超过三个数量级，并且与扩散相比具有更大的相对贡献。预测排放率变化的关键是更好地了解不同排放途径（尤其是淡化）的主要驱动因素。集水区衍生的有机物质以及水柱叶绿素a升高注意力集中与开eb率增加有关。Little Nerang大坝（LND）是澳大利亚昆士兰州的一个亚热带淡水水库，在主要流入臂附近都是持续高沸腾状态，主要流入臂既是集水有机物质的沉积区，又是水柱叶绿素a浓度升高的区域。在LND上进行了为期一年的排放速率研究，在此期间评估了甲烷沸腾潜能，评估了水柱叶绿素a的浓度，底部水温和沉积物有机质含量。其中包括从坝壁到沸腾区的高空间采样（259个点）的样带，以探讨水柱叶绿素a与水柱之间的关系。浓度，沉积物有机质含量和甲烷沸腾。这些结果表明，沸腾与邻近主要流入点的大型森林凋落物沉积有关，沉积物有机质含量明显高于水库主体。