北京玉渊潭水化学特征及其控制因素分析

为了解城市景观水体的水化学特征,选择北京玉渊潭为例,分别对丰水期与枯水期湖水进行采样研究.结果表明玉渊潭湖水偏弱碱性,阳离子以Ca2＋、Na＋为主,阴离子以HCO 3-、SO42-为主,水化学类型为HCO 3--Ca2＋型.枯水期离子浓度低于丰水期,但离子含量序列一致均为：HCO 3-〉SO42-〉Ca2＋〉Na＋〉Cl-〉Mg2＋〉K＋.Gibbs图解得出玉渊潭主要离子来源于上游河流的岩石风化过程,表明即使是大都市的河流及湖泊,流域内的岩石风化仍是控制河水主离子成分的主导因素.相关分析得出玉渊潭水体中Cl-、NO 3-、SO42-、NH 4＋和Mg2＋之间有很好的正相关关系,表明它们有共同的来源,受人类活动影响较大.各种含氮营养物质的存在表明玉渊潭水体已经受到污染,主要由上游农业生产地区化肥的施用、工业生产及人类活动排放的废物引起.

Water chemistry characteristics and controlling factors in the Yuyuantan Park in Beijing

Water samples were collected and analyzed during the wet season and dry season in Yuyuantan Park of Beijing,in order to understand water chemistry characteristics in urban landscape water.The results show that the water is alkalescent,in which Ca2+ and Na+ are the dominant cations,HCO-3and SO42-are the dominant anions,the type of water belongs to HCO-3-Ca2+.The ion concentration in wet season is lower than dry season,but the ion content sequences are:HCO-3> SO42-> Ca2+> Na+> Cl-> Mg2+> K+.The major origin of water ions is the weathering processes of rocks in upstream rivers from Gibbs distribution pattern.Cl-、NO-3、SO42-、NH+ 4and Mg2+ real a very strong positive correlation through correlation analysis.This indicates these chemical components have common source and greatly influenced by human activities.The existence of various nitrogen nutrient indicate the water in Yuyuantan Park has been contaminated,and these pollutants may originate from fertilizer application,industrial production and the waste of human activities in upstream areas.This research enriches and develops water chemistry characteristics of urban landscape water.Additionly,it has very important theoretical and practical significance in term of the environment situation,governance and management decisions for Yuyuantan Park.