深圳市酸雨特征及其成因分析

Analysis of Characteristics and Sources of Acid Rain in Shenzhen City

研究了深圳市1991～2004年的酸雨时空分布、降雨化学组成及其成因分析。结果表明，深圳市酸雨14年间pH平均值为4．98，酸雨频率为44．2％；降雨中SO4^2-与NO3^-比值是3．78：1，低于全国平均值6.4；酸雨夏秋两季较为严重，主要集中在3～9月份，而冬春两季降雨酸度和酸雨频率均较小；酸雨强度由西向东依次减弱；降雨中离子来源主要是工业和交通排放的酸性污染物，但陆地源和海洋源对降雨酸度的影响也较大。

The temporal-spatial distribution, chemical composition, and the source analysis of acid rain in Shenzhen City from 1991 to 2004 were studied in this paper. It was shown that the average pH value of Shenzhen acid rain during 14 years, the frequency was about 44.2%. The ratio of SO4^2- to NO3^- was 3.78：1, lower than the average pH value of whole country. Acid rain was more serious in Shenzhen during Summer and Autumn, mainly occurring from March to September, in contrast, the frequencies of acid rain in Winter and Spring were less than those in Summer and Autumn. The intensity of acid rain decreased from west to east. The sources of ions in acid rain mainly came from the acid pollutants of industrial and traffic emission, but the influences of land and ocean sources were also bigger.