小型腐殖质湖泊的碳收支:湖泊对北方集水区有机物质循环重要性的一个实例  

A Carbon Budget of a Small Humic Lake:An Example of the Importance of Lakes for Organic Matter Cycling in Boreal Catchments

作　　者：Sebastian Sobek Bjrn Sderbck Sara Karlsson Eva Andersson Anna Kristina Brunberg 李四海 

机构地区：[1]瑞典乌普萨拉大学

出　　处：《AMBIO－人类环境杂志》2006年第8期461-467,共7页

摘　　要：由于通常是大范围的细菌呼吸作用和沉积物中有机碳的有效埋藏,湖泊在北方景观有机物质循环中发挥着重要作用。为了评估碳收支对与有机物有关的放射性核素在环境中迁移的潜在影响,我们基于一种质量平衡方法,计算了瑞典的一个小腐殖质湖的碳收支,该湖位于一个放射性废料潜在最后埋藏点的附近。我们发现该湖是一个净异养的生态系统,从集水区和现有大型植物生产物中补充得到有机碳输入。有机碳最大的汇点是水生细菌的呼吸作用和随后向大气释放CO_2。虽然每年埋藏在沉积物中的有机碳是一个比较小的汇,但它却导致湖中最大碳库的形成。因此,湖泊也许同时分散和聚集从最后埋藏点中泄漏的有机伴生的放射性核素。Lakes play an important role in the cycling of organic matter in the boreal landscape,due to the frequently high extent of bacterial respiration and the efficient burial of organic carbon in sediments.Based on a mass balance approach,we calculated a carbon budget for a small humic Swedish lake in the vicinity of a potential final repository for radioactive waste in Sweden,in order to assess its potential impact on the environmental fate of radionuclides associated with organic matter.We found that the lake is a net heterotrophic ecosystem,subsidized by organic carbon inputs from the catchment and from emergent macrophyte production.The largest sink of organic carbon is respiration by aquatic bacteria and subsequent emission of carbon dioxide to the atmosphere.Although the annual burial of organic carbon in the sediment is a comparatively small sink,it results in the build-up of the largest carbon pool in the lake.Hence,lakes may simultaneously disperse and accumulate organic-associated radionuclides leaking from a final repository.

关 键 词：物质循环 碳收支 集水区 腐殖质 湖泊 北方 放射性核素 实例 

分 类 号：X21[环境科学与工程—环境科学]