The western part of the Kuroshio Intermediate Water originates from the nutrient-rich South China Sea intermediate water which upwells onto the East China Sea (ECS) continental shelf and contributes a large amount of nutrients to the ECS. This contribution, especially for phosphorus, is far more than the inputs from the phosphorus-deficient Yangtze and Yellow Rivers. Mass balance calculations reveal that the net denitrification rate in the ECS shelf is 95¿50¿109 mol N yr-1, which is more than the total riverine supply of nitrogen. The nutrient supply allows the ECS to produce 1030¿310¿109 moles dissolved organic carbon and 709¿280¿109 mol particulate organic carbon for a total of 1739¿870¿109 mol organic carbon per year, which translates to a new production rate of phytoplankton as 64¿32 mg C m-2 d-1 or 15% of the average primary production rate. The downslope transport of modern particulate carbon is 2547¿1250¿109 mol yr-1, of which 695¿350¿109 mol yr-1 is organic. This value is only 12% of the offshore dissolved organic carbon transport of 5563¿1700¿109 mol yr-1. The alkalinity budget, never attempted before, indicates that there is a substantial amount of alkalinity generation in the sediments (3.9¿3.9 mmol m-2 d-1) due to anaerobic respiration such as by iron and sulfate reductions. ¿ 1999 American Geophysical Union