Chemical Characteristics of Atmospheric Wet Deposition in Winter and Its Forestry Canopy Interception Mechanism in Red Soil Hilly Area
(2.Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China 100101)
【Abstract】In order to disclose the interception mechanism of forestry canopy to atmospheric wet deposition, the concentrations of nutrients (C, N, P, S) and trace elements (K, Ca, Na, Mg, Al, Fe, Mn, Zn) in wet deposition and through fall in winter were monitored in Subtropical Qianyanzhou basin. The results showed that the wet deposition in this area was mainly acid deposition, the pH of which ranged from 3.49 to 7.0. The major components of wet deposition were nitrate (NO3−) and sulfate ions (SO42−) , the monthly average deposition fluxes of which were 4.68 kg·hm−2and 0.36 kg·hm−2, and trace elements (Zn, K, Ca) with monthly average deposition fluxes of 1.72, 0.56 and 0.36 kg·hm−2, respectively. Non-metallic nutrients such as dissolved organic carbon (DOC), dissolved total nitrogen (DTN), total phosphorus (TP), Ca, Mg and Mn were easy to leach, the dilution rate could reach up to 64.69%, 206.75%, 301.38%, 137.94%, 405.25% and 1 226.60%, respectively. Moreover, the Zn and sulfate ion (SO42−) could be well absorbed by forests canopy, the absorption proportions of which were 73.50%and 12.51%, respectively.
【Keywords】 red soil; wet deposition; canopy interception; through fall; trace metal;
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