酸雨、土壤酸化与森林衰亡

本文主要综述酸雨通过土壤酸化导致森林衰亡方面的国外最新研究进展。对于森林衰亡的原因目前主要有几种假说:综合胁迫;土壤的酸化——铝毒害;气态污染物（SO2,O3）;酸雨——镁亏缺和过量营养物铵/氮沉降等。这些假说都有一定的事实依据,并直接或间接涉及酸雨问题。酸雨在很大程度上是通过土壤——植物系统间接危害森林的。长期持续的酸雨输入导致土壤酸度升高,减少可利用态磷,降低有机质的分解速率,抑制氮的矿化作用;土壤酸度升高使钙、镁等离子易被淋失造成营养元素亏缺,溶出铝和某些重金属离子毒害植物。 

Acid Rain, Soil Acidification and Forest Decline

The present paper is a review of the new progress of study on forest decline due to soil acidification from acid rain.There are five hypatheses about the cause of forest decline:1) general stresses; 2) soil acidification-Al phyto-toxicity; 3) Gaseous pollutant (SO2 , O3 ) injury; 4) acid rain--Mg deficiency and 5) excess nutrient NH4+/N deposition. Acid rain affects forest by alterating the chemical characteristics of the soil and plant. chronic import of acid rain could cause the PH value of soil solution to decrease, nutrient elements essential for plant such as Ca、 Mg to leach from soil, Al and some heavy metals to liberate and become phyto-toxic, and the cycle of N or P between soil and plant to become slower.