长江入海口北岸单站降水组分10年变化状况探讨

分析2001—2010年南通市区城中子站降水监测点位数据,得出降水中起致酸作用的阴离子硫酸根、硝酸根、氟离子和氯离子中除硝酸根呈现显著性上升趋势,其余上升趋势不明显;氯离子、钠离子与降水量存在高度线性负相关,硫酸根、硝酸根与降水量分别为低度非线性负相关和正相关,其他项目与降水量为显著性非线性负相关;将pH分5级,pH<4.7为重酸雨频率,pH4.7～5.0为较重酸雨频率,pH5.0～5.3为中度酸雨频率,pH5.3～5.6为轻度酸雨频率,pH≥0.56为非酸雨频率,其结果表明:南通市区2009、2010年酸雨频率降低,分别为44.1%和38.2%,主要是重酸雨频率减少,非酸雨频率增加;2003、2007年酸雨频率升高,分别为67.4%和69.8%,主要是重酸雨频率增加,非酸雨频率减小;降水量大小与电导率浓度高低没有对应性;阴阳离子浓度总量逐年、逐月同步变化;阴离子中硫酸根、硝酸根浓度逐年、逐月变化量与幅度较大;阳离子中钙离子、铵离子浓度逐年、逐月变化量与幅度较大;阴阳离子浓度逐年、逐月占比呈准对称形。

Yangtze River North-Component Single Station Precipitation Changes in the Situation of 10 Years

This paper analyzes the 2001 to 2010 in Nantong city station precipitation monitoring data, conclude: precipitation of acid effect of anions sulfate, nitrate, fluoride and chloride in addition to nitrate showed a significant upward trend, the rising trend is not obvious; chlorine ion, sodium ion and precipitation in the presence of highly negative linear correlation, sulfate, nitrate and precipitation were low non-linear negative and positive correlation with precipitation, other projects as the significant nonlinear negative correlation; the value of pH 5, pH<4.7 for heavy acid rain frequency, pH value of 4.7-5 more the heavy acid rain frequency, pH value of 5-5.3 for moderate acid rain frequency, pH value of 5.3-5.6 for mild acid rain frequency, pH value is more than 0.56 for acid rain frequency when considering the results show that, Nantong city in 2009 and 2010 the acid rain frequency decreased to 44.1% and 38.2% respectively, mainly heavy acid rain frequency was reduced, the acid rain frequency increases; 2003 and 2007 acid rain frequency increased respectively 67.4% and 69.8%, primarily heavy acid rain frequency increase, not reduce acid rain frequency; precipitation size and conductivity concentration no corresponding; ion concentration Gross year after year, month after month synchronous changes; anionic sulfate, nitrate concentration in year after year, month by month variation and range is bigger; cationic ion, ammonium ion concentration in year after year, month after month variation and range is bigger; ion concentration year after year, month by month proportion is quasi symmetric shape.