酸雨区亚热带针阔混交林的冠层淋溶特征  

Canopy Leaching of the Subtropical Mixed Forest Under Acid Rain in Hunan Province

作　　者：张西林[1,2] 蒋益民 张龚 向仁军[1] 

机构地区：[1]湖南省环境保护科学研究院 [2]湖南大学环境科学与工程学院长沙410082 [3]湖南省环境监测中心站

出　　处：《林业科学》2007年第7期1-4,共4页Scientia Silvae Sinicae

基　　金：国家杰出青年科学基金(50425927;50225926);2000年度高等学校优秀青年教学科研奖励计划项目;高等学校博士学科点专项科研基金(20020532017)资助。

摘　　要：2001年1月至2002年6月在湖南韶山对亚热带针阔混交林4个采样区进行酸雨监测,分析林内穿透水中主要离子的淋溶特征。结果表明:大气降水经过森林冠层后pH值明显升高,亚热带针阔混交林对SO24-、NO3-、Mg2+、NH4+和Na+具有吸收作用,SO24-、Ca2+和Mg2+的冠层淋溶百分率随降雨量的增加明显减少。Ca2+、K+和Cl-的冠层淋溶百分率随着pH值增加而增加。韶山地区在常年酸沉降作用下,森林冠层对酸性离子SO42-、NO3-的吸收作用最强。根据18个月离子浓度平均值来计算,韶山地区森林冠层离子的淋溶序列为:K+>Ca2+>Cl->Mg2+>SO24->NO3->NH4+>Na+。The leaching law of major ions in acid precipitation in a subtropical mixed forest was examined basing on the experiment at 4 sample sites in Shaoshan, Hunan Province from January 2001 to June 2002. The results showed that the pH value obviously increased and the ionic uptake evidences were proved by SO4^2- , NO3^- ,Mg^2＋ , NH4^＋ and Na＋ , when rain water passing through the canopy. The dissolved percentage of SO4^2- , Ca2^＋ and Mg^2＋ had the tendency to reduce with the increase of the rain-fall. Dissolved percentage of Ca^2＋ , K^＋ and Cl^- showed a tendency to increase along with increase of pH value. Shaoshan forest canopy has the strongest effects on the uptake of SO4^2- ,NO3^- under acid rain. The ionic leaching order in Shaoshan forest canopy was K^＋〉Ca^2＋〉Cl^-〉Mg^2＋〉SO4^2-〉NO3^-〉NH4^＋〉Na^＋.

关 键 词：酸雨 淋溶 亚热带森林 韶山 

分 类 号：X517[环境科学与工程—环境工程]