重庆市涪陵区近10年酸雨变化特征分析

为了解重庆市涪陵区的酸雨变化特征及降水对酸雨pH值的影响，本研究采用2005—2014年涪陵区的酸雨和降水数据，应用统计学方法分析降水与酸雨pH值月、季、年变化的相关性。结果表明：涪陵区酸性降水频率为42.13%，以弱酸性降水为主，自2011年起几乎无强酸性降水发生；酸雨pH值秋季最小、冬季最大，6月最小，7月最大。降水总量、有效降水日数和大量级降水占比都会影响酸雨的月、季、年变化，并不能单独由一个指标来说明酸雨的变化规律；其中，大量级降水占比对酸雨pH值影响最大。上述结果表明，了解降水与酸雨pH值的变化规律为有效防治酸雨和减少酸雨的危害提供了一定的依据。

Variation Characteristics of Acid Rain: Recent 10 Years in Fuling of Chongqing

In order to know the variation characteristics of acid rain and the effect of precipitation on pH value of acid rain in Fuling of Chongqing, based on the data of acid rain and precipitation in Fuling from 2005 to 2014, this paper used statistical method to analyze the monthly, seasonal and annual correlation between precipitation and pH value of acid rain. The results indicated that: the frequency of acid rain was 42.13% in Fuling, and dominated by weakly acidic precipitation; there was little strong acid rain since 2011; the lowest pH value in fall and the highest pH value in winter were observed, we also found the smallest pH value in June and the largest pH value in July; furthermore, the total precipitation, effective precipitation day, and heavy precipitation ratio influenced the monthly, seasonal and annual change of acid rain, which meant the variation characteristics of acid rain could not be illustrated by a single index; among the influencing factors, the heavy precipitation ratio had the most influence on pH value of acid rain. The above results show that understanding the variation characteristics of acid rain can provide a basis for preventing and mitigating its harm.