湖南韶山大气降水及森林降水离子分布特征

The Distributional Characteristics of Ions in the Bulk Precipitation and the Forested Throughfall in Shaoshan,Hunan Province

以2001年1月—2002年6月韶山大气降水和森林降水的监测数据为基础,对韶山的大气降水和森林林冠穿透水的化学成分的分布特征进行了分析。结果表明,大气降水与森林降水的阴离子均以SO42-为主,其浓度分别占相应的总阴离子的52 87%和48 92%;阳离子以Ca2+为主,其浓度分别占总阳离子的37 62%和42 81%。森林穿透水中的离子浓度明显增加,增加倍数最高达9 7倍。采用主成分分析方法对大气降水和森林穿透水中的化学组分进行了分析,主成分分析结果表明,大气降水中的2个主要成分占总方差的92 76%,森林穿透水中的3个主要成分占到总方差的96 70%。

The distributional characteristics of chemical compositions of the bulk precipitation and the forested throughfall in Shaoshan area are summarized based on the monitoring data from January 2001 to June 2002.The results show that the dominant anion is SO\-4\+\{2-\} both in the bulk precipitation and the forested throughfall,accounting for 5287% and 4892% respectively,and the dominant cation is Ca\+\{2+\},accounting for 3762% and 42\^81% respectively.The ion concentrations in the forested throughfall significantly increase.Compared to the bulk precipitation,the largest concentration of ions increases up to 9\^7 times in the forested throughfall.The chemical constituents of the bulk precipitation and the forested throughfall are analyzed using the principal component analysis to find the possible sources of the measured chemical species.Two major componets that account for 92\^76% in total variance are extracted in the bulk precipitation and three major components that account for 96\^70% in total variance are extracted in the forested throughfall.