Characteristics of nitrogen and phosphorus dry and wet deposition fluxes and contribution rate in Dianchi Lake Basin
In order to explore the contribution rate of dry and wet deposition of nitrogen and phosphorus to exogenous nutrients in the Dianchi Lake Basin,rainwater and dust fall in six functional areas of the Dianchi Lake Basin were collected in 2021,the mass concentrations of different forms of nitrogen and phosphorus in atmospheric deposition were measured,and the distribution characteristics of nitrogen and phosphorus atmospheric deposition in the Dianchi Lake Basin were analyzed.The annual deposition fluxes of nitrogen and phosphorus and their contribution rates to the loading of Dianchi Lake were also estimated.The results showed that the annual atmospheric TN and TP wet deposition fluxes were 20.244-220.938 kg/km2 and 1.155-65.826 kg/km2,and dry deposition fluxes were 44.275-481.120 kg/km2 and 4.255-111.840 kg/km2,respectively.The functional areas of industrial production and mineral exploitation were the areas with the highest nitrogen and phosphorus deposition fluxes,respectively.DIN and DIP were the main forms of nitrogen and phosphorus in atmospheric deposition.The average annual atmospheric deposition loads of nitrogen and phosphorus into the lake in the basin were 1 018.92 and 88.88 t,respectively.The direct atmospheric deposition load on the lake surface of Dianchi Lake accounted for 3.70％and 2.35％of the total pollution load into the lake in the basin,respectively.The proportion of atmospheric deposition into the lake load in other areas of the basin was 8.69％and 6.26％,respectively,in the river inflow load of the basin.In summary,the atmospheric deposition of nitrogen and phosphorus in the basin has gradually become one of the important sources of exogenous pollutants in Dianchi Lake.In-depth understanding of its spatial and temporal distribution characteristics and contribution rate to the lake were important prerequisites for further strengthening basin management and reducing the input of exogenous pollutants into the lake.
Dianchi Lake Basinatmospheric depositionnitrogenphosphorusdeposition loadcontribution rate
NETL
NSTL
万方数据
