太湖梅梁湾温室气体(CO_2,CH_4和N_2O)浓度的昼夜变化及其控制因素  

DIURNAL VARIATIONS IN THE CONCENTRATION OF GREENHOUSE GASES(CO_2,CH_4 AND N_2O)IN THE MEILIANG BAY OF TAIHU LAKE

作　　者：王仕禄[1] 

机构地区：[1]中国科学院地球化学研究所环境地球化学国家重点实验室,贵阳550002

出　　处：《第四纪研究》2010年第6期1186-1192,共7页Quaternary Sciences

基　　金：国家科技部水专项项目(批准号:2009ZX07101-013)资助

摘　　要：营养盐载荷增加、富营养化以及全球增温等对湖泊温室气体的影响目前认识还很有限,原因之一在于对湖泊温室气体产生的动力过程了解不够深入,缺少高时间分辨率的现场观测数据。为了解决这一问题,在富营养的太湖梅梁湾水体,每一小时收集一个样品,直接分析N_2O和CH_4饱和度、CO_2分压(pCO_2)以及其他地球化学参数。在7月份的观测中,N_2O和CH_4显示出显著的昼夜变化规律。相关性分析表明,有机质降解是调节湖泊N_2O和CH_4变化的重要因素之一。虽然人为活动是控制湖泊温室气体大规模变化的主要因素,但沉积物-水界面的生物地球化学过程对温室气体浓度在短时间尺度上的变化有着重要的影响。研究结果揭示了湖泊温室气体除了受人为活动影响外,湖泊自身的生物地球化学过程也是重要的调控因素之一。The process of greenhouse gas production in lakes in response to increased nutrients, eutrophication and warming is still unclear partially due to the lack of high-resolution, in-situ observations. In this study, we con an hourly measurement of N2O and CH4 saturations （relative to atmospheric partial pressure ） and CO2 global ducted partial pressures in the Meiliang Bay of Taihu Lake, a eutrophical lake in Eastern China to understand the mechanism responsible for the production of greenhouse gases in lacustrine environments. The data indicate that N2O and CH＋ saturations in July display a distinct pattern of diurnal variations. Correlative analyses suggest that the mineralization of organic matters may be one of the factors that control variations of N2O, CH＋ and CO2 on very short time scales. We infer that biogeochemical processes occurring at the sediment-water interface have significant impacts on the regulation of short-time productions of greenhouse gases, while long-time changes in the production and emission of lacustrine greenhouse gases would be related to the loading of anthropogenic pollutants.

关 键 词：富营养湖泊 人为活动 温室气体 昼夜变化 

分 类 号：P343.5[天文地球—水文科学]