Using δ15N Value to identify nitrate source in Taihu Lake and some major inflow rivers

摘要

Nitrate contaminate of fresh water lake is an increasingly serious problem with the development of Suzhou, Wuxi, the important cities of Jiangsu Province, east China. The stable isotope nitrogen-15 is a natural indicator of nitrogen (N) source and biogeochemistry. Nitrate concentration in rivers and west Taihu Lake were higher than east lake in most cases. δ15N of NO3- was not correlated with NO3- concentration, and we combined analysis the NO3-/Cl- and plot of δ15N and NO3-, could draw a conclusion that in the east Taihu Lake δ15N variations might indicate a major effect of mixing, whereas the denitrification were dominant in west part of Taihu lake.