中国地表水酸化敏感性的区划

地表水体的酸化与集水区的许多环境因子密切相关，如土壤对酸的缓冲能力、基岩中和酸沉降的能力以及土地利用方式等.其中，土壤的抗酸化能力是关键因素.因此可以根据集水区土壤、基岩和土地利用方式等信息来评估地表水在不同流量下发生酸化的可能性.本研究成功地应用已有资料和数据得到了我国地表水对酸沉降的敏感性等级，并绘制了地表水酸化敏感性区划图.结果表明，我国大部分地表水对酸化并不敏感.极易酸化和较易酸化的地表水主要分布在东北的北部地区，占所有国土面积的2.67%，是该地区强酸性漂灰土、酸性母岩和针叶林植被共同作用的结果.对酸化敏感性为中级和低级，即不易酸化的地表水主要分布在东北暗棕壤地区和南方富铝土区域，占所有国土面积的15.2%.其余82.11%国土面积上的地表水对酸化不敏感，完全不可能发生酸化.北方地区主要是由于土壤的强缓冲能力，而在南方，石灰质土壤以及耕作农田的广泛分布是最重要因素.南方重酸雨区由于土壤对酸化并不很敏感，因此在短期内不会出现大面积水体酸化现象.由于东北近年来频频出现酸雨，因此东北的酸沉降必须及早防治，以免出现大面积酸化水体.

Mapping Sensitivity of Surface Waters to Acidification in China

Acidification of surface waters can be decided by some environmental factors, such as soil's buffering capacity, neutralization capacity of bedrock to acid deposition and types of land use, among which the most important factor is the soil's resistance to acidification. Therefore, information about soils, geology and land use can be used to predict the regional occurrence of acidification surface waters under different flows. In this paper, information and data about Chinese soils, geology and land use types were collected to determine and to map the sensitivity of surface waters to acidification. Results showed that in China, most surface waters were not sensitive to acidification. The few most sensitive surface waters were located in the north part of Northeastern China, accounting for 2.67% of all the country land. It was the combined results of strongly acidified ortho podzolic soil, acidified bedrock and coniferous forest. Surface waters which were not very sensitive to acidification were distributed both in the region of dark brown forest soil in Northeastern China and in the ferralsol and yellow-brown earth area in Southern China, occupying 15.2% of all the country land. The other surface waters which distributed on 82.11% of all the country land were not sensitive to acidification at all. Most in the Northern China because of the high resistance of soils to acidification and the others were in the Southern China where calcareous soils and agricultural lands were widely distributed. Since soils were quite resistant to acid, acidification of surface waters of large area will not likely occur in the southern region of China suffering from heavy acid deposition in the near future. Nevertheless, the acid deposition in Northern China should be controlled as soon as possible in case that acidified surface waters will be found there.