Integrated evaluation of water quality and quantity of Yellow River

An integrated water quantity and quality evaluation method has been set up for a river, and the integration concept of available water resources has been put forward. The concepts of water resources functional capacity and deficit have been developed, and the concepts of water environment functional capacity and deficit have also been put forward. Based on the monthly data of water quality and quantity as well as the withdrawals, an integrated evaluation of water quantity and quality have been conducted for the Yellow River. The results indicate that the total water resources availabilities were 25.5, 34.3 and 35.5 billion m~3 occupying about 80.2%, 78.2% and 82.0% of the total runoffs in 1997, 1998 and 1999, respectively. And the averages of water resources functional capacity and deficit were 423.50×10~8m~3 and 78.97×10~8m~3 in these three years, respectively. For the main pollution parameter-COD_(Mn),the averages of water environment functional capacity and deficit were 28321.94kg and 20.64kg in these three years; for the other main pollution parameter NH~+_4-N,they were 3439.30kg and 69.98kg, respectively. Therefore, the influence of NH~+_4-N on the total quantity of available water resources was more than that of COD_(Mn). Water resources functional capacity and water environment functional capacity were much higher than water resources functional deficit and water environment functional deficit, respectively. it suggests that actual water quality was better than the requirement of water resources function in most of the times.