Benthic nutrient fluxes in the intertidal flat within the Changjiang (Yangtze River) Estuary  

作　　者：GAO Lei LI Daoji WANG Yanming YU Lihua KONG Dingjiang LI Mei LI Yun FANG Tao 

机构地区：[1]State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China [2]State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China

出　　处：《Chinese Journal Of Geochemistry》2008年第1期58-71,共14页中国地球化学学报

摘　　要：In an annual cycle from March 2005 to February 2006, benthic nutrient fluxes were measured monthly in the Dongtan intertidal flat within the Changjiang (Yangtze River) Estuary. Except for NH4+, there always showed high fluxes from overlying water into sediment for other four nutrients. Sediments in the high and middle marshes, covered with halophyte and consisting of macrofauna, demonstrated more capabilities of assimilating nutrients from overlying water than the low marsh. Sampling seasons and nutrient concentrations in the overlying water could both exert significant effects on these fluxes. Additionally, according to the model provided by previous study, denitrifica- tion rates, that utilizing NO3- transported from overlying water (DW) in Dongtan sediments, were estimated to be from -16 to 193 μmol·h-1·m-2 with an average value of 63 μmol·h-1·m-2 (n=18). These estimated values are still un- derestimates of the in-situ rates owing to the lack of consideration of DN, i.e., denitrification supported by the local NO3- production via nitrification.In an annual cycle from March 2005 to February 2006, benthic nutrient fluxes were measured monthly in the Dongtan intertidal flat within the Changjiang （Yangtze River） Estuary. Except for NH4^＋, there always showed high fluxes from overlying water into sediment for other four nutrients. Sediments in the high and middle marshes, covered with halophyte and consisting of macrofauna, demonstrated more capabilities of assimilating nutrients from overlying water than the low marsh. Sampling seasons and nutrient concentrations in the overlying water could both exert significant effects on these fluxes. Additionally, according to the model provided by previous study, denitrification rates, that utilizing NO3- transported from overlying water （Dw） in Dongtan sediments, were estimated to be from -16 to 193 μmol·h^-1·m^-2 with an average value of 63 μmol·h^-1·m^-2 （n=18）. These estimated values are still underestimates of the in-situ rates owing to the lack of consideration of DN, i.e., denitrification supported by the local NO3^- production via nitrification.

关 键 词：潮水 长江 深海生物 元素化合物 

分 类 号：P734[天文地球—海洋化学]