中文摘要：

选取三峡库区缙云山小流域针阔混交林作为研究对象,对其大气降水、穿透雨、树干茎流、地表径流等水文过程中的pH值及Na＋、K＋、Ca2＋、Mg2＋等离子含量进行研究,结果表明：（1）大气降水pH值为5.31,呈酸性,已属于酸雨范围（pH〈5.65）。相对于大气降水,针阔混交林穿透雨和树干茎流离子含量均大幅增加。穿透雨和树干茎流中,Mg、Cu元素的变异系数均小于大气降水,而K、Zn和Mn均大于大气降水。地表径流中Ca元素含量最高,为16.416mg/L,Mn元素含量最低,几乎检测不到。各元素含量排序为：Ca〉K〉Na〉Mg〉Zn〉Fe〉Cu〉Mn。地下径流中,Ca元素是含量增加最多的养分元素,各元素含量排序为：Ca〉K〉Na〉Mg〉Zn〉Cu〉Fe=Mn。（2）Cu元素在穿透雨和树干茎流中均出现了负淋溶,其余各元素浓度均有所增加。如果林木长期处于酸雨逆境下,将会导致部分营养元素大量流失,并最终造成林木营养亏损且影响其生长。

英文摘要：

Broad-leaved forest was selected as object of study in Jinyun mountain.The ion content was compared in hydrological processes（atmospheric precipitation,throughfall,stemflow,surface runoff and subsurface runoff）,such as pH and Na＋,K＋,Ca2＋,Mg2＋,and so on.The results showed that：（1）pH value of atmospheric precipitation was 5.31,and it belongs to acid rain range（pH5.65）.Relative to atmospheric precipitation,ion content of throughfall and stemflow were significantly increased.Coefficient of variation of Mg,Cu was less than precipitation in the throughfall and stemflow,while the K,Zn and Mn were greater than the atmospheric precipitation.Ca content was the highest in the surface runoff,and was 16.416 mg/L.But Mn content was the lowest,and was almost undetectable.The order of the content of each element was： Ca K Na Mg Zn Fe Cu Mn.In the underground runoff,Ca content was the most of increased nutrient elements.The order of the elements content was： Ca K Na Mg Zn Cu Fe=Mn.（2）Cu leaching was negative in the throughfall and stemflow,the rest of the elemental concentrations were increased.If in the long run,the trees were in an acid rain situation,it would lead to a huge loss of some of the nutritional elements,and ultimately resulting in the forest nutrient losses and affecting their growth.