Atmospheric deposition of nitrogen and phosphorus into the Hengmen of Pearl River Estuary
珠江口横门大气氮、磷干湿沉降的初步研究

To understand the characteristics of atmospheric nutrient deposition into the Pearl River Estuary, measurements of dry and wet depositions of nitrogen and phosphorus were made at Hengmen in Zhongshan from December 2006 to November 2007. Results showed that, on an annual basis, volume-weighted concentrations in wet deposition for ammonium nitrogen (NH4+-N), nitrate nitrogen (NO3--N), total nitrogen (TN), total phosphorus (TP) were 0.82, 0.52, 2.14, 0.039mg.L-1, respectively; their corresponding annual deposition fluxes (dry + wet) were 1.584, 1.142, 4.295 and 0.055g.m-2.a-1, respectively. The budget of wet deposition corresponded with that of dry deposition for NH4+-N, NO3--N and TN, and wet deposition was the major source for TP. Seasonal change of total deposition fluxes for TN showed no significant difference among spring, summer and autumn, while that for TP was highest in summer, lower in autumn, and lowest in winter.