Abstract
Lake Furen is an enclosed estuary facing the Nemuro bay in the North-Western Pacific.The measure which prevents water pollution of Lake Furen by pollution load from upstream farm is considered.It is required to evaluate the effects of the measures against water pollution in advance.Field observation of water quality, sediment and currents was performed in 2006.It is found that nutrients in the inner part of the lake were high especially after rain and that in the mouth is low.They are strongly dependent on salinity. Although the exchange of seawater is helpful for maintaining the good water quality of the mouth area, the seawater does not reach the inner part of Lake Furen.It was proved by the numerical simulation.
