共查询到20条相似文献,搜索用时 702 毫秒
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李彩宜 《中国环境管理干部学院学报》2007,17(3):76-78
随着水质自动监测站数量的不断增加,水质自动监测站的管理问题日渐突出,由于缺乏必要的管理经验和管理制度,出现了各种各样的管理模式。水质自动监测站的建成实现了间断性人工监测向连续性自动监测的转变,实现了水质监测实时远程控制的连续性,高频次的监测结果更能客观、准确地判断断面水质的质量状况,使得河流水质评价更具科学性、准确性,能更好地服务于环境管理工作。 相似文献
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基于MODIS数据的太湖蓝藻水华时空分布规律研究 总被引:1,自引:0,他引:1
利用EOS/MODIS遥感影像数据,采用蓝藻水华分级评价方法和蓝藻水华发生频率分析方法,对2010年~2013年不同级别太湖蓝藻水华时空分布规律进行分析和研究,以期为太湖蓝藻水华预警、监控、治理工作提供技术支持.结果表明:(1) 2010年~2013年,全太湖共发生蓝藻水华354次,其中小型水华发生次数最多,蓝藻水华级别越高,发生次数越少.(2)年际变化上,蓝藻水华发生次数总体趋于平稳,蓝藻水华发生呈现“小型多发、中大型少发、重大型偶发”趋势,蓝藻水华发生规模呈显著缩小趋势.(3)月际变化上,蓝藻水华主要发生在8 ~10月,8月和9月尤其是太湖蓝藻水华的高发月份.发生规模上,4~6月蓝藻水华发生规模较小,7月开始规模逐步扩大,到9月达到顶峰,10月规模有所缩小.(4)空间变化上,太湖西部沿岸是太湖蓝藻水华首次爆发最频繁的水域.从空间分布频率来看,太湖西部沿岸区尤其宜兴沿岸是蓝藻水华爆发频率最高的水域. 相似文献
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A Drinking Water Crisis in Lake Taihu, China: Linkage to Climatic Variability and Lake Management 总被引:26,自引:0,他引:26
Boqiang Qin Guangwei Zhu Guang Gao Yunlin Zhang Wei Li Hans W. Paerl Wayne W. Carmichael 《Environmental management》2010,45(1):105-112
In late May, 2007, a drinking water crisis took place in Wuxi, Jiangsu Province, China, following a massive bloom of the toxin
producing cyanobacteria Microcystis spp. in Lake Taihu, China’s third largest freshwater lake. Taihu was the city’s sole water supply, leaving approximately
two million people without drinking water for at least a week. This cyanobacterial bloom event began two months earlier than
previously documented for Microcystis blooms in Taihu. This was attributed to an unusually warm spring. The prevailing wind direction during this period caused
the bloom to accumulate at the shoreline near the intake of the water plant. Water was diverted from the nearby Yangtze River
in an effort to flush the lake of the bloom. However, this management action was counterproductive, because it produced a
current which transported the bloom into the intake, exacerbating the drinking water contamination problem. The severity of
this microcystin toxin containing bloom and the ensuing drinking water crisis were attributable to excessive nutrient enrichment;
however, a multi-annual warming trend extended the bloom period and amplified its severity, and this was made worse by unanticipated
negative impacts of water management. Long-term management must therefore consider both the human and climatic factors controlling
these blooms and their impacts on water supply in this and other large lakes threatened by accelerating eutrophication. 相似文献
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为提高水库水华发生预警能力,从水华形成机理着手,引入营养盐条件、水动力条件、光热条件和浮游植物生长状况,建立水库水华发生影响因素模型。首先,基于文献研究,建立水库水华发生影响因素体系,共包含10个指标;其次,利用解释结构模型(ISM)建立水库水华发生影响因素递阶结构模型;最后采用网络层次分析法(ANP)构建权重模型,并借助Super Decision(SD)软件求解。结果表明:叶绿素a浓度、悬浮物浓度、磷浓度、氮浓度、铁等微量盐浓度、水流流速、温度和溶解氧为表层直接影响因素,光照和风速为深层根本影响因素;重要度排序为:叶绿素a浓度、悬浮物浓度、磷浓度、水流流速、氮浓度和溶解氧。 相似文献
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Raman K. Raman Ralph L. Evans 《Journal of the American Water Resources Association》1985,21(2):315-321
Johnson Sauk Trail Lake remains highly eutrophic, even though the watershed has long been returned to an undisturbed condition with permanent vegetative cover and with little or no land disturbance in the watershed. Internal regeneration of nutrients has been identified as the major source of nutrients to the lake. Lake destratification, selective harvesting and removal of weeds, and control of algal blooms using chelated copper sulfate application followed by potassium permanganate application have all been chosen as management techniques for improving water quality conditions in the lake. These in-lake techniques are considered not as palliative measures, but as necessary tools in enhancing the lake's water quality characteristics. 相似文献
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为研究昆山市农产品产地环境质量,采用采样分析方法,对昆山市农产品产地的代表性土壤、灌溉水、渔业水质量进行了定点取样分析检测,在此基础上依据国家相关环境质量标准进行了单因子污染指数法和综合污染指数法评价。结果表明,该市58.1%的耕层土壤为安全、清洁,36.6%的耕层土壤处于警戒限,为尚清洁,3.8%的耕层土壤为轻污染,1.5%的耕层土壤为中污染;76.0%的灌溉水为安全、清洁,24.0%的灌溉水处于警戒限,为尚清洁;73.5%的渔业水为安全、清洁,23.5%的渔业水处于警戒限,为尚清洁,3%的渔业水为轻污染。 相似文献
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河流水质模型在双流县流域治理中的应用 总被引:1,自引:0,他引:1
研究利用现有的河流水质模型,构建了一个可实时模拟河流水环境质量变化状况的动态模型。模型采用一维稳态单组分水质模型对河流的CODCr、NH3-N的降解进行计算,采用多宾斯-坎普稳态模型对河流的BOD、DO变化情况进行计算。模型引入水文数据、水质监测数据、环境统计数据、社会统计公报数据,以Excel作为数据平台,可以反演出河流不同月份、不同区段的污染物降解系数。研究将该模型应用于双流县的流域治理,以在锦江双流段的应用为例进行了具体说明。根据2008年双流县河流的相关数据,研究使用该模型反演出了锦江双流段的污染物降解系数,并对其反映的流域污染状况进行了分析。随后,研究使用该模型已计算出的岷江中段河流的降解系数,模拟计算了4种情景下锦江双流段出境断面的可能水质变化,以验证拟定的双流县流域治理方案的预期效果。模型具有实用性和进一步扩展的功能。 相似文献
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ABSTRACT. The fundamental hypothesis of this paper is that the stratified-mixed states which occur annually in lakes play a dominant role in the movement of nutrient-rich material from the lake bottom upward into the water column. The stratified-mixed history has been used previously to develop a Fourier type, semi-infinite slab energy model to represent the lake surface temperature, thermal profile, and thermocline position with Julian day (Thibodeaux, 1975). The present paper extends the semi-infinite slab idea to include a Fickian type model for the upsurge of nutrients from the sediment-water interface upward. Relations will be developed for the rate of nutrient upwelling into the epilimnion and the photoactive zone of a lake. A lake time constant emerges from the model equations. This constant is thought to be important in predicting the likelihood of a fall algal bloom. Results of model verification attempts on three lakes are presented. 相似文献
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Xiaobo Chao Yafei Jia F. Douglas Shields Sam S.Y. Wang Charles M. Cooper 《Journal of environmental management》2010,91(7):1456-1466
A three-dimensional water quality model was developed for simulating temporal and spatial variations of phytoplankton, nutrients, and dissolved oxygen in freshwater bodies. Effects of suspended and bed sediment on the water quality processes were simulated. A formula was generated from field measurements to calculate the light attenuation coefficient by considering the effects of suspended sediment and chlorophyll. The processes of adsorption–desorption of nutrients by sediment were described using the Langmuir Equation. The release rates of nutrients from the bed were calculated based on the concentration gradient across the water–sediment interface and other variables including pH, temperature and dissolved oxygen concentration.The model was calibrated and validated by applying it to simulate the concentrations of chlorophyll and nutrients in a natural oxbow lake in Mississippi Delta. The simulated time series of phytoplankton (as chlorophyll) and nutrient concentrations were generally in agreement with field observations. Sensitivity analyses were conducted to demonstrate the impacts of varying suspended sediment concentration on lake chlorophyll levels. 相似文献
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YSI 6600-V2多功能水质自动监测仪采用荧光原理快速测定水体中浮游植物蓝绿藻的密度,梅梁湖夏季水华高发期时,湖体中的浮游植物几乎全部是蓝绿藻。传统的浮游植物监测前处理方面就需要24~48 h,最终要数天后才有镜检结果,导致浮游植物数据滞后,不能很好的应用到预警监测中。通过比对相关性验证,保证荧光法数据的可信度,提高工作效率,为预警监测提供有力的支持。 相似文献
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Multivariate statistical characterization of water quality in Lake Lanier, Georgia, USA 总被引:1,自引:0,他引:1
Watershed monitoring programs depend on water quality characterization data collected for many parameters, at many times and places, and with limited resources. Our objective is to present a strategy that reduces the measured parameters, locations, and frequency without compromising the quality of the monitoring program. One year of twice-monthly (growing season) and monthly (dormant season) water quality data collected from 17 lake and 10 tributary sites are used in conjunction with multivariate statistical techniques to improve the utility of collected data by identifying key parameters and monitoring locations. Factor analysis shows that tributary water quality data consists of three components-stormwater runoff, municipal and industrial discharges, and ground water-which can be distinguished using total suspended solids, total dissolved solids, and alkalinity plus soluble reactive P, respectively. Lake water quality characterization is more ambiguous than tributary water quality characterization, but factor analysis indicates that anoxia associated with lake stratification is the largest source of lake water quality variation, followed by nutrient abundance, and finally by biomass abundance. Cluster analysis suggests that tributary and lake monitoring stations can be consolidated. Reducing the number of parameters and stations frees up resources for increased monitoring elsewhere. 相似文献