WANG Jing-fu1, 2, CHEN Jing-an1,*, ZENG Yan1,2, YANG Yong-qiong1,2, YANG Hai-quan1,2, JI Yong-xue1,2

(1.State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China; 2. Graduate University of  Chinese Academy of Sciences, Beijing 100049, China)

Abstract:  Micro-scale distributions of oxygen and H2S across the water-sediment interface in Lake Hongfeng, which is a deep lake in southwestern China, were measured with microelectrodes. Results showed that the diffusive fluxes, J, of O2 across the water-sediment interface in two sampling sites were respectively 5.80 and 7.65 mmol m-2d-1.Oxygen penetration depths in the sediments were 3.6±0.3 and 3.4±0.9 mm, respectively. Vertical distribution of H2S in the sediments was related with sediment composition, oxygen consumption rate and the activity of sulfate-reducing bacteria (SRB). High-resolution microelectrode technique, whose determination results have been proved to be reliable, was of great value in the study of biogeochemical processes across the water -sediment interface in a lake.

Key words:  microelectrode; water-sediment interface; biogeochemical process

EARTH AND ENVIRONMENT Vol. 41, No.1, Tot No.291, 2013, Page 65-70