Dry and wet phosphorus deposition characteristics and influencing factors in different farmland ecosystems in the Erhai Lake basin
To clarify the characteristics and influencing factors of dry and wet phosphorus(P)deposition from different farmland ecosystems,the typical vegetable and rice-rotated systems in the Erhai Lake basin were taken as the research objects,and the temporal distribution characteristics of phosphorus deposition,differences,and their influencing factors in the two typical farmland ecosystems were analyzed.The results showed that the averaged PM2.5 concentration in the vegetable system was 41.6µg·m-3,which was significantly higher than that in the rice-rotated systems(34.9µg·m-3).The dry deposition of total P(TP)of vegetables and rice-rotated systems which was mainly distributed in winter and spring(from January to April)were 0.233 and 0.084 kg·hm-2,respectively,of which the dissolved TP(DTP)accounted for more than 90%,and the vegetable system was significantly higher than that of the rice-rotated system(P<0.01).The wet depositions of TP in vegetable and rice-rotated systems were 0.72 and 0.91 kg·hm-2,respectively,and DTP was also the main type of P depositions.The TP depositions in vegetable and rice-rotated rotation ecosystems were both dominated by wet deposition,which accounted for 75.6% and 91.6%,respectively,and the TP depositions in summer and autumn(from June to November)accounted for 70.7% and 76.4% of the total annual deposition,respectively.Wind speed,particulate phosphorus concentration,atmospheric humidity and precipitation were the key influencing factors of phosphorus dry deposition,while wind speed,atmospheric temperature,humidity and precipitation were the key influencing factors of phosphorus wet deposition.It can be seen that crop planting patterns and meteorological factors affected PM2.5,rainfall and phosphorus deposition rate,which thereby changed the dry and wet phosphorus deposition rates in different farmland systems.
Erhai Lake basinfarmland systemphosphorus depositiondry depositionwet deposition
万方数据
维普
