柳州市2009-2014年空气污染变化

Variations of Air Pollutants in Liuzhou from 2009 to 2014

中文关键词:  大气  柳州  在线  年趋势  标准

英文关键词:air  Liuzhou  online  annual trend  standard

中文摘要:

      近年来,城市空气污染日益严重,已成为公众广泛关注的环境问题之一。 柳州是中国西部的工业重镇、广西有名的工业城市,位列国家划定的113 个大气污染防治重点城市之中,是广西第一个开展PM_2.5 监测的城市。本研究于2009-2014 年连续6 年对柳州市大气主要污染物SO₂、NO₂、PM₁₀ 和PM_2.5 的浓度进行在线观测,获得了污染物的长期时间和空间分布特征。结果显示,SO₂ 浓度呈逐年下降趋势,并于2011 年达标之后显著下降,2014 年相比2009 年下降了50.0%;NO₂ 浓度一直在低于标准以下波动(24.6~35.1μg/m³);PM₁₀ 浓度呈逐年增长趋势,并从2011 年开始超标,2014 年相对于2009 年增长了69.3%。各污染物浓度都具有显著的季节变化:冬季> 秋季> 春季> 夏季。SO₂、NO₂、PM₁₀ 和PM_2.5 的浓度冬季相比夏季分别提高82.9%、56.3%、66.9% 和133.6%。冬季SO₂ 和秋冬季PM₁₀ 超标,PM_2.5 除7月外全线超标。PM_2.5/PM₁₀ 的比值冬季也高于夏季,表明冬季更易富集细颗粒。各污染物浓度也表现出不同的空间分布。九中各污染物的浓度都最高,可能与其离柳州钢铁公司距离较近有关。SO₂ 除九中外,其他站点均达标。NO₂ 全部达标。PM₁₀ 市监测站和九中超标。PM_2.5 所有站点超标严重。本 研究结果表明,柳州市煤烟型污染得到有效控制,但颗粒物污染,尤其是细颗粒物污染日益严重。

英文摘要:

      In recent years, urban air pollution is increasingly serious and has become one of the environmental issues attracting wide public concern. Liuzhou is a famous industrial city in western China, a member of the 113 major cities designated by the national environment protection bureau of China and the first city in which PM_2.5 monitoring has been carried out in Guangxi province. Six-year continuous online measurements of the atmospheric main pollutants, such as SO₂, NO₂, PM₁₀ and PM_2.5 were conducted during 2009-2014 in Liuzhou, Guangxi province. The spatio-temporal patterns of the pollutants were obtained. SO₂ levels showed a downward trend, met the standard (GB3095-2012) in 2011 and plummeted since then, with a 50.0% decrease from 2009 to 2014. NO₂ levels stayed below the standard all the time, but exhibited obvious annual fluctuation. PM₁₀ levels showed a rising trend and exceeded the standard in 2011, with a 69.3% increase from 2009 to 2014. The pollutants showed consistent seasonal variations: winter > autumn > spring > summer, with growth rates of 82.9%, 56.3%, 66.9% and 133.6% from summer to winter for SO₂, NO₂ and PM₁₀, respectively. While SO₂ and PM₁₀ levels exceeded the standards in winter and fall-winter, respectively, PM_2.5 levels exceeded the standard in all seasons except in July. PM_2.5/PM₁₀ ratios were also higher in winter than in summer, reflecting heavier fine particle pollution. The pollutants also showed distinct spatial variations, but all of them exhibited highest levels in No. 9 middle school, possibly due to its adjacency to Liuzhou Iron and Steel Co., Ltd. SO₂ and NO₂ levels at all sites met the standard, except for SO₂ at No. 9 middle school. PM₁₀ levels at Liuzhou environmental monitoring station and No. 9 middle school exceeded the standard. PM_2.5 levels at all the sites seriously exceeded the standard. These results indicate that the coal-smoke pollution has been effectively controlled, while particulate air pollution, especially the fine particle pollution has become a growing problem in Liuzhou.