程海水质变动特征与水安全预警因素识别  

Dynamic changes of Chenghai Lake water quality and identification of the early warning factors of its water quality safety

作　　者：董云仙[1] 谭志卫[1] 朱翔[1] 罗玉[2] 

机构地区：[1]云南省环境科学研究院,昆明650034 [2]昆明理工大学环境科学与工程学院,昆明650093

出　　处：《安全与环境学报》2012年第4期136-140,共5页Journal of Safety and Environment

基　　金：云南省科技计划项目(2009CA002)

摘　　要：采用GPS定位,在程海湖设置了3个断面9个采样点,对程海水质进行了为期1 a的研究,分析了水质时间变化特征和空间变化特征,辨识出影响程海水质时空变动的主要因素,提出水质安全预警级别与阈值判定建议。结果表明:2009年10月—2010年9月程海水质综合评价为Ⅲ类,其中有半年(1月、4月、5月、8月、9月、12月)水质类别为Ⅳ类,不能达到水环境保护目标要求;另半年水质类别为Ⅲ类,达到水环境保护目标要求。超标项目有总磷(TP)、高锰酸盐指数(CODMn)、总氮(TN)、溶解氧(DO),超标率分别为35.2%、14.8%、10.2%和9.3%,最大超标倍数分别为2.10倍、0.95倍、1.83倍和0.03倍,年平均质量浓度分别为0.046mg/L、5.15mg/L、0.773mg/L和7.51mg/L。水平变化特征为:湖南部—湖中部—湖北部水质逐渐下降;湖东部—湖中部—湖西部水质逐渐变差,湖东南角水质最好,湖西北角水质最差,湖中心水质并不明显优于湖周水质,其差异性多因TP、TN的差异引起。垂向分布上则比较均匀,但CODMn、TN、TP在湖底层明显升高,其原因相对复杂。辨识出影响程海水质变动的主要因素是叶绿素a(Chl.a)、总氮(TN)、总磷(TP)、高锰酸盐指数(CODMn)、透明度(SD)。提出了水环境安全预警体系中5项指标的水质安全预警级别与判定阈值,建议三级黄色预警值分别是0.020 mg/L、0.60 mg/L、0.030mg/L、3.5 mg/L和3.0m。As is known, it is a key to develop effective water quality warning systems for lake water study. The present paper is aimed at to bring forward a lake water quality prediction model by identifying the warning factors of the water quality. For our research purpose, we have initiated a data collection program from Oct. 2009 to Sept. 2010 in hoping to identify the water quality safety warning factors for Chenghai Lake, Yunnan, with the water quality samples covering three cross-sections and nine sampling stations. The analysis of the collected data led us to the following conclusions： The water quality of Chenghai Lake can generally be classified into Class III, though its quality can likely be lowered into Class IV during the different periods of time （Sept and Dec. 2009, as well as Jan. , April, May, and August 2010） as the result of monitoring registration, indicating degradation caused by the local pollution. To be more accurate, the pollution effects can be shown as follows： the annual mean concentrations of total phosphorus （ TP）, Permanganate Index （ CODMn ）, the total nitrogen （TN）, and the dissolved oxygen （DO） were registered to be 0.046 mg/L, 5.15 mg/L, 0.773 mg/L and 7.51 rag/L, with excessive frequency of 35.2%, 14.8%, 10.2%, and9.3%, respectively. For the four constituents, the maximum excessive ratios are 210% , 95%, 183% , and 3%, respectively. The water quality in Chenghai Lake clearly demonstrates the spatial patterns, whereby the water quality in general declines from the south to the north, as well as from the east to the west. The south-east direction monitoring resuits of the lake turn to be the best in quality in the lake whereas that of the north-west direction proves to be the worst. Besides, the water quality in the middle parts are not remarkably better than that in the stations closer to the lakeside, though different in constituent composition of the water quality, such as the presence of TN and TP. However, no obvious vertical variability fails to be observed,

关 键 词：环境学 水质 变动特征 预警因素 程海 

分 类 号：X524[环境科学与工程—环境工程]