Antarctic Dry Valley Lakes: Pathways of Organic Matter Production and Decomposition

该项目的总体目标是在生态系统层面上了解南极干谷湖泊Fryxell内碳、氮、硫和水循环的速率和途径，并为该系统开发一个定量概念模型，以便与类似的生态系统进行比较。了解在这个物理上相对简单的非生态性系统中控制元素循环的过程，不仅可以增进对南极湖泊的了解，还可以增进对其他水生系统的了解，特别是海洋和河口沉积物系统和分层水柱。具体目标是确定物理过程与生物过程在控制南极干谷湖泊中生物活性气体与非生物活性气体的组成和分布方面的相对重要性。将确定水柱与藻垫光合作用速率对系统有机质生产的相对重要性及其对生态系统碳循环的相对贡献。估算湖泊生态系统内有机物分解的年总速率。在这个项目中收集的数据的最终综合将成为弗里克塞尔湖的碳平衡模型。

The overall goal of the project is to develop an ecosystem level understanding of the rates and pathways of carbon, nitrogen, sulfur and water cycling within an Antarctic dry valley lake, Lake Fryxell, and to develop a quantitative conceptual model for the system for comparison to similar ecosystems. Understanding the processes controlling elemental cycling in this physically relatively simple amictic system will enhance an understanding not just of Antarctic lakes but of other aquatic systems, especially marine and estuarine sediment systems and stratified water columns. The specific objectives are to determine the relative importance of physical versus biological processes in controlling the composition and distribution of bio-active versus non-bioactive gases in Antarctic dry valley lakes. A determination will be made of the relative importance for system organic matter production of rates of water column versus algal mat photosynthesis and their relative contribution to the ecosystem carbon cycle. The overall annual rate of organic matter decomposition within the lake ecosystem will be estimated. The final synthesis of data collected in this project will be a model of carbon balance for Lake Fryxell.