摘要
以缙云山3种典型林分为研究对象,分别收集大气降水、穿透水、枯落物层滤液和壤中流,研究3种典型林分不同层次对酸沉降的缓冲作用。结果表明:(1)缙云山降水酸性较强,pH=4.57,SO24-/NO3-=9.78,酸雨类型为典型的硫酸型酸雨。(2)酸雨对于盐基离子的淋溶以Ca2+淋溶量最大,Na+、K+分别在林冠层和土壤层表现为吸附现象,NH4+在林冠层表现为淋溶,在枯落物层和土壤层表现为吸附。(3)森林生态系统主要通过盐基离子与降水中H+发生交换作用,从而降低降水的酸度,3种林分的酸缓冲能力大小顺序为毛竹林>针阔混交林>阔叶林。同一林分,不同层次的缓冲能力大小为土壤层>枯落物层>林冠层。(4)淋滤液的pH值与酸根离子与盐基离子比值(k)呈显著负相关关系(r=-0.918,p<0.01),k值越大,说明酸雨状况越严重。
Through chemical analysis of rainfall, throughfall, litter-leaching and interflow, the acid buffer capacity of three typical forests（mixed wood, broadleaf forest, bamboo forest） was studied. The results showed that the rainfall of Jinyun mountain was very acid, pH=4.57, SO4^2/NO3 =9.78, and the acid rain was typical sulfuric acid type. Ca2＋ from the rainfall was high, while Na＋ and K＋ were negative in the rainfall and soil respective. NH＋ was leaching in the canopy and uptake in the litter and soil. The exchange of H＋ and CEC was the main way of increasing pH for the forest. The acid buffer capacities of three types forests were ranked as follows： Bamboo forest 〉mixed wood 〉broadleaf forest. The acid buffer capacities of the different levels of a same stand were ranked as follows： Soil〉litter〉canopy. The pH of leaching was highly negative correlated with the value of the ratio of acid radical ion and CEC（k）, r=-0. 918, p〈0.01. The high value of k indicated the stronger acid rain.
出处
《水土保持学报》
CSCD
北大核心
2013年第2期1-7,共7页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(31100515)
高等学校博士学科点专项科研基金项目(20110014120001)
关键词
酸沉降
盐基离子
酸缓冲能力
林分类型
acid deposition
base cations
acid buffer capacity
vegetation type
