Study On Spatial And Temporal Variation Characteristics Of Atmospheric Phosphorus Deposition In Typical Urban Functional Areas

Atmospheric phosphorus deposition is an important component of phosphorus cycle,nutrient resource characteristics and regional distribution differences is typical.With the rapid development of urbanization,the city becomes the hot spot of atmospheric phosphorus power and deposition,the variation of phosphorus deposition,the influence factors of phosphorus deposition and the input of phosphorus deposition in the ecosystem have attracted much attention in the field of research.Therefore,this study selects the typical functional area of west Sichuan Plain?rural residential area,urban residential area,agricultural production function area,industrial production function area?as study area,three methods of dry settlement are compared,the spatiotemporal variation law of atmospheric phosphorus deposition in urban areas is illustrated,the main influencing factors were discussed,and the phosphorus deposition flux of field ecosystem is estimated.The main results are as follows:?1?The dry deposition fluxes of atmospheric phosphorus obtained from three methods of sampling dry phosphorus deposition are significantly related?P<0.05?,and the dry deposition flux of atmospheric phosphorus among the three can be converted in a unified manner based on a certain mathematical conversion relation.The atmospheric wet substitution method is more suitable for the monitoring and research on the atmospheric phosphorus deposition in typical urban functional areas.?2?The annual mean deposition flux of atmospheric phosphorus in the research region is7.32±0.65kg P hm^-2 a^-1 in total,the most of which is dry deposition?70.9%?,the dry and wet deposition fluxes of atmospheric phosphorus are significantly different.From the perspective of spatial distribution,the differences of atmospheric phosphorus deposition flux in different functional areas are significant?P<0.05?,and agricultural production function area>urban residential area>industrial production function area>rural residential area.On the time scale,the atmospheric phosphorus deposition fluxes in different seasons are significantly different?P<0.05?,and summer>autumn>spring>winter.?3?During the continuous deposition observation,the wet deposition flux of atmospheric phosphorus shows a significant linear positive correlation with the rainfall?P<0.05?,and the rainfall can explain the 64.5%variation of wet deposition flux of atmospheric phosphorus.The dry deposition flux of atmospheric phosphorus shows a significant linear negative correlation with the sampling time?P<0.05?,and the sampling time can explain the 47.6%variation of dry deposition flux of atmospheric phosphorus.The multivariate regression equation obtained from this study can better estimate the atmospheric phosphorus deposition flux in the time period?summer?when rainfall is relatively frequent in the research region through the related meteorological factors.?4?The contribution of atmospheric phosphorus deposition to the growing season of wheat,canola,rice and maize in the research region can reach 14.2%,30.4%,14.2%and 30.4%of better fertilizing amount respectively.