Study On Characteristics Of Atmospheric Dry And Wet Deposition And Its Influence On Water Body In Handan

Atmospheric deposition has become a major route for exogenous substances to enter the ecosystem.In order to determine the pollution characteristics of atmospheric deposition and its impact on the water body,three monitoring points were set up in Handan City according to the characteristics of the functional area,and samples of atmospheric dry and wet deposition from December 2017 to November 2018 were collected.The concentration of total nitrogen,total phosphorus,heavy metal elements?Cu,Zn,Cd,Mn,Cr,Pb,Co?and water-soluble ions(K⁺,Na⁺,NH₄⁺,Ca²⁺,Mg²⁺,Cl^-,NO₃^-,SO₄^2-)in the samples were tested by ultraviolet spectrophotometry,inductively coupled plasma optical emission spectrometry,atomic fluorescence spectrometry and ion chromatography.The fluxes were calculated,their spatial and temporal variation characteristics,influencing factors and source analysis were analyzed,which provided a scientific basis for air pollution prevention and protection of water ecosystems.?1?The monthly wet deposition fluxes of nitrogen and phosphorus was basically consistent with the change of monthly rainfall.The monthly dry deposition fluxes of nitrogen and phosphorus was basically consistent with the change of monthly dust fluxes.Atmospheric wet deposition mainly consisted of nitrogen deposition,and phosphorus deposition mainly consisted of dry deposition.The annual average nitrogen deposition fluxes of the three sampling stations was 2.68t/?km²·a?,and the annual average total phosphorus deposition fluxes was 62.06kg/?km²·a?.The annual atmospheric nitrogen deposition in the main urban area was 243.05t,and the annual atmospheric phosphorus deposition was 5.63t.The annual atmospheric nitrogen deposition in all waters in the main urban area was 4.77t,and the atmospheric phosphorus deposition was 110.47kg.?2?In the atmospheric dry deposition samples,the concentration and fluxes of Mn were the largest,and the smallest were Cd.The monthly fluxes of the nine heavy metals in HG were higher than KY and DW.The proportion of fluxes of Mn in wet deposition was reduced by 34%compared to dry settling.The heavy metal fluxes in dry deposition accounted for 86%of the total fluxes of dry and wet deposition.The average fluxes of heavy metal wet and dry deposition was 21.24mg/?m²·month?.The enrichment factor of various heavy metal elements varied widely,and the nine heavy metal elements of HG were greater than 10.The principal component analysis showed that the motor source,coal source,metallurgical chemical source and waste combustion source were the four main sources.?3?Among the dried deposition samples,SO₄^2-,Ca²⁺and NO₃^-were the three most important water soluble ions,they accounted for 86%of the total ions concentration,and the anions accounted for 67%of the total ion concentration.the annual fluxes of water-soluble ions in HG dry deposition was much higher than the other two stations.Among the wet deposition samples,SO₄^2-,NH₄⁺,Ca²⁺and NO₃^-were the four most important water soluble ions,accounted for 86%of the total ions concentration.Autumn contributed the most to the water-soluble ion fluxes in dry deposition,while spring contributed the most to the water-soluble ion fluxes in wet deposition.The average fluxes of dry and wet deposition was 1284.60kg/?km²·month?.Correlation analysis method and characteristic ratio method analysis showed that SO₄^2-and NO₃^-in dry and wet deposition mainly came from coal combustion,and Ca²⁺and Mg²⁺were mainly from soil dust.