Research On Chlorophy Ⅱ Fluorescence Characteristics And Growth Action Law Regularity Of Eleocarpus Sylvestris And Lithocarpus Glaber Under Different Simulated Acid Rain

Acid rain has a long lasting harm on terrestrial ecosystems and particularly a serious harm to theforest. Therefore, it is significant to improve the experimental design to study in-depthly of acid rain onthe size of the trees influence and the process of comparison to the direct and indirect effect on forests.The results can reveal the mechanism of acid rain on forests.In this study Elaeocarpus (Elaeocarpus sylvestris) and Lithocarpus (Lithocarpus glaber) are selectedby improving the experimental design to simulate the three acid rain leaching ways as two subtropicalBroadleaf species:(1) acid rain is leaching on trees leaves only;(2) acid rain is directly input into thesoil;(3) acid rain is directly leaching on the leaves before input into the soil. Set severe acid rain(pH2.5), moderate acid (pH4.0) and mild acid(pH5.6)，through determination of seedling growthindicators and the relative chlorophyll content and chlorophyll fluorescence parameters to study thegradient of the same acid rain stress on the seedlings of the two species. On the other hand seek theirrespective trends from May, August, November of the two kinds of plant seedlings in response patternof the different treatments of acid rain respectively.The main results are as following:1. Ground and whole treatment can promote Elaeocarpus sylvestris seedling height growth atpH2.5the pH4.0of acid rain and the pH4.0with pH5.6soil treatment can promote stone oakseedlings height growth2. The SPAD of Elaeocarpus sylvestris is significant differences among other groups when inpH2.5and pH4.0with the whole treatment.3. Fv/Fm and Fv/Fo in the pH2.5whole and pH5.6soil treatment of two species and the pH5.6with soil treatment of the Lithocarpus glaber are significantly higher than the rest treatments.In spring and summer the Yield under different concentrations of acid rain of Lithocarpusglaber is higher than Elaeocarpus sylvestris.The conclusion of this experiment is: The growth and photosynthetic characteristics of thefluorescence parameters of Elaeocarpus sylvestris at the whole treatments of pH2.5、pH4.0acid rainhave a role in promoting. The growth and photosynthetic characteristics of the fluorescence parametersof Lithocarpus glaber at the whole treatments of pH4.0、pH5.6acid rain have a role in promoting. Thewhole treatment of moderate and severe have a role in growth promoting to Elaeocarpus sylvestriswhile The soil treatment of moderate and mild acid rain have a role in growth promoting to Elaeocarpussylvestris while The soil treatment of moderate and mild acid rain have a role in growth promoting toLithocarpus glaber.