Responses of Typical Forest Litters to Acid Deposition in Southwestern Subtropical Region
The hydro-chemical properties of litter layers of 6 typical forests including Pinus massoniana × Adinandra bockiana × Gordonia acuminata Chang mixed forest(forest type I ), Lindera kwangtungensis × Symplocos setchuanensis mixed forest (forest type Ⅱ ), Phyllostachys pubescens forest (forest type Ⅲ ),Syrnplocos setchuanensis × Cunninghamia Lanceolata (forest type Ⅳ), Pinus massoniana forest(forest type Ⅴ ) and shrub forest(forest type Ⅵ)in Jinyun mountain were studied by the simulated acid rain experiment.The results showed: ①Litter leaching pH values of 6 typical forest stands reduced with the decrease of pH of simulated acid rain. The acid buffer ability of litter layer in forest type V was best. ②Base cation(Ca2+ ,Mg2+ ,K+ ,Na+ ,NH4+ ) concentrations of all 6 typical forest litter leaching increased with the decrease of pH of simulated acid rain. Under the eluviation of different simulated acid rain (pH value: 2.7, 3. 5), the base cation concentrations of litter leaching of forest type V were always largest: 0. 143 6 mmol/L (pH 2.7),0. 074 0 mmol/L (pH 3.5). Under the eluviation of pH 4.5 simulated acid rain, the base cation concentrations of litter leaching of forest type Ⅱ were the largest: 0. 138 9 mmol/L. ③The concentrations of Al3+ ,Fe,Mn, Zn in litter leaching of 6 typical forest stands increased dramatically when the pH value of simulated acid rain was 2.7. And the concentrations of Al3+ (0. 018 2 mmol/L), Fe(0. 004 4 mmol/L), Mn(0. 010 7 mmol/L) and Zn(0. 002 5 mmol/L) in forest type V litter leaching were larger than that of the others. It indicated that forest type Ⅴ was more vulnerable to these toxic elements.
国家科技期刊平台
NSTL
万方数据
维普
