Spatial Distribution Characteristics and Environmental Effect of N and P in Water Body of Taihu Lake

The characteristics of spatial distribution of nitrogen and phosphorus in water were studied.The results showed that concentrations of total nitrogen/phosphorus in water from Meiliang Bay,Zhusan Bay,Gonghu Bay,West and Central Taihu Lake were obviously higher than those from any other region of Taihu Lake.The spatial distribution of dissolved nitrogen/phosphorus and detritus nitrogen/phosphorus was consistent with that of total nitrogen/phosphorus.The concentrations of dissolved nitrogen and detritus nitrogen significantly correlated with those of total nitrogen with r_(DN)=(0.819?2) and r_(DeN)=(0.696?9),respectively;the concentrations of dissolved and detritus phosphorus in water also significantly correlated with that of total phosphorus with r_(DP)=(0.747?7) and r_(DeP)=(0.926?0),respectively.The discrepancy in spatial distribution of chlorophyll a(Chla) in water was distinctly obvious,the highest level appeared in West Taihu Lake(179.2(μg·L~(-1))±25.9(μg·L~(-1))),and the lowest in East Taihu Lake(11.3(μg·L~(-1))±2.7(μg·L~(-1))).There were significantly linear relationships between total nitrogen,detritus nitrogen,total phosphorus,dissolved phosphorus,detritus phosphorus,permanganate index,pH value and suspended solids and the content of Chla with r_(TN)=(0.662?2),r_(DeN)=(0.873?9),r_(TP)=(0.813?0),r_(DP)=(0.407?7) and r_(DeP)=(0.878?1),r_(COD)=(0.868?9),r_(pH)=(0.517?3) and r_(SS)=(0.533?4),respectively;while dissolved nitrogen,electric conductivity and alkalinity did not affect Chla in water from Taihu Lake.