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471.
Contemporary urban air quality management requires the use of appropriate systems which include air quality models, a Geographical Information System (GIS) and a combination of expert systems and decision support tools, while at the same time possessing the capability to receive information from in situ measurements. Until recently, the relation between Information Technology capabilities and the system's design and architecture were poorly addressed, mainly due to technological limitations posed. Moreover, air quality management scenario design issues were partially considered, because of the difficulty in aggregating complex, air quality related issues, in a comprehensive and effective manner, from the end users point of view. In the present paper the use of Environmental Telematics is discussed as a framework for the development of urban air quality management systems, while a comprehensive approach for the application and evaluation of relevant scenarios is presented.  相似文献   
472.
浑河源区水生生物与水质评价   总被引:1,自引:0,他引:1  
对浑河源区的浮游植物、原生动物、轮虫、底栖动物、鱼类和水生维管束植物调查发现 :源区水生物种类绝大多数为贫营养型清水指示种类。数量明显少于下游。源区水质优良 ,水质基本处于自然状态  相似文献   
473.
Morgan Island, located within the ACE Basin National Estuarine Research Reserve in South Carolina, is home to the only free-ranging colony of rhesus monkeys (Macca mulatta) in the continental United States. The purpose of this study was to assess environmental impacts of the monkey colony on water quality in adjacent tidal creeks and on island vegetation. Three tidal creeks were sampled: Morgan Creek, adjacent to the monkey colony; Back Creek, on Morgan Island not adjacent to the colony; and Rock Creek, on a nearby island unoccupied by monkeys. Temperature, salinity, pH, dissolved oxygen, nutrients and fecal coliform bacteria were measured six times at three sites in each of these creeks, and vegetation change analysis was conducted in a geographic information system using satellite imagery. Results showed elevated fecal coliform concentrations in the Morgan Creek site immediately adjacent to the colony, though no samples exceeded the standard set for recreational water use. Ribotyping reconnaissance matched four Escherichia coli isolates from Morgan and Back Creeks to the monkeys, identifying the colony as one source of fecal coliform bacteria, though relative source loadings could not be quantified. Significant differences were not observed between ammonia or orthophosphate levels in Morgan Creek relative to the other creeks tested; and vegetation change analysis showed a 35% increase in canopy cover between 1979 and 1999. Overall, these results suggest that the rhesus colony’s environmental impacts are localized and minimal. Results from this study provide baseline data on Morgan Island and may be useful in management decisions regarding the future of the monkey colony.  相似文献   
474.
The long-term water quality monitoring program implemented by the Massachusetts Water Resources Authority in 1992 is extensive and has provide substantial understanding of the seasonality of the waters in both Boston Harbor and Massachusetts Bay and the response to improvements in effluent quality and offshore transfer of the effluent in September 2000. The monitoring program was designed with limited knowledge of spatial and temporal variability and long-term trends within the system. This led to an extensive spatial and temporal sampling program. The data through 2003 showed high correlation within physical parameters measured (e.g., salinity, dissolved oxygen) and in biological measures such as chlorophyll fluorescence. To address the potential sampling redundancies in the measurement program, an assessment of the impact of reduced levels of monitoring on the ability to make water quality decisions was completed. The optimization was conducted by applying statistical models that took into account whether there was evidence of a seasonal pattern in the data. The optimization used model survey average readings to identify temporal fixed effects, model survey-average-corrected individual station readings to identify spatial fixed effects, corrected the individual station readings for temporal and spatial fixed effects and derived a correlation model for the corrected data, and applied the correlation model to characterize the correlation of annual average readings from reduced monitoring programs with true parameter levels. Reductions in the number of sampling stations were found less detrimental to the quality of the data for annual decision-making than reductions in the number of surveys per year, although there is less of a difference in this regard for dissolved oxygen than there is for chlorophyll. The analysis led to recommendations for a substantially lower monitoring effort with minimal loss of information. The recommendation supported an annual budget savings of approximately $183,000. Most of the savings was from fewer surveys as approximately $21,000 came from the reduction in the number of stations monitored from 21 to 7 and associated laboratory analytical costs.  相似文献   
475.
In this study, some heavy metals concentrations (Zn, Pb, Fe, Mn, Cu, Ni) and other physico-chemical parameters were studied during October 2001 to September 2003 in Karanja reservoir, Bidar district. Water quality parameters were collected monthly basis whereas heavy metals were analyzed by Atomic Adsorption Spectrometer (AAS). Heavy metals have shown within the permissible limits, except Fe and Ni were recorded higher values in southwest monsoon, where as Mn has showed higher concentration in northeast monsoon in and summer. All other physico-chemical parameters are with in the permissible limit. Water is moderately hard and reservoir is productive.  相似文献   
476.
Transportation system has contributed significantly to the development of human civilization; on the other hand it has an enormous impact on the ambient air quality in several ways. In this paper the air and noise pollution at selected sites along three sections of National Highway was monitored. Pakistan National Highway Authority has started a Highway Improvement program for rehabilitations and maintenance of National highways to improve the traffic flows, and would ultimately improve the air quality along highways. The ambient air quality and noise level was monitored at nine different locations along these sections of highways to quantify the air pollution. The duration of monitoring at individual location was 72 h. The most of the sampling points were near the urban or village population, schools or hospitals, in order to quantify the air pollution at most affected locations along these roads. A database consisting of information regarding the source of emission, local metrology and air quality may be created to assess the profile of air quality in the area.  相似文献   
477.
环境质量评价的生物方法研究   总被引:1,自引:0,他引:1  
环境质量的生物评价是以生物对环境污染的表现为基础的.环境质量评价的生物方法包括环境指示生物的选择,环境质量生物评价指标的确定和环境质量分类等3个步骤.论述了环境污染的生物表现,提出了选择环境指示生物的原则,给出了环境质量生物评价的3类指标,建立了环境质量4级分类体系.  相似文献   
478.
Effective water resources management programs have always incorporated detailed analyses of hydrological and water quality processes in the upland watershed and downstream waterbody. We have integrated two powerful hydrological and water quality models (SWAT and CE-QUAL-W2) to simulate the combined processes of water quantity and quality both in the upland watershed and downstream waterbody. Whereas the SWAT model outputs water quality variables in its entirety, the CE-QUAL-W2 model requires inputs in various pools of organic matter contents. An intermediate program was developed to extract outputs from SWAT at required subbasin and reach outlets and converts them into acceptable CE-QUAL-W2 inputs. The CE-QUAL-W2 model was later calibrated for various hydrodynamic and water quality simulations in the Cedar Creek Reservoir, TX, USA. The results indicate that the two models are compatible and can be used to assess and manage water resources in complex watersheds comprised of upland watershed and downstream waterbodies.  相似文献   
479.
The European Operational Smog (EUROS) integrated air quality modelling system has been extended to model fine particulate matter (PM). From an extended literature study, the Caltech Atmospheric Chemistry Mechanism and the Model of Aerosol Dynamics, Reaction, Ionisation and Dissolution were selected and recently coupled to EUROS. Currently, modelling of mass and chemical composition of aerosols in two size fractions (PM2.5 and PM10–2.5) is possible. The chemical composition is expressed in terms of seven components: ammonium, nitrate, sulphate, elementary carbon, primary inorganic compounds, primary organic compounds and secondary organic compounds. Calculated PM10 concentrations and chemical composition are presented for two summer months of the year 2003 (1 July to 31 August).  相似文献   
480.
固城湖春季水环境因子空间变异及其原因探讨   总被引:4,自引:1,他引:3  
在现场采样数据的基础上,运用Arc GIS的地统计学组件分析了固城湖春季水环境因子空间变异规律,并从污粢源分布、水生植物密度差异方面探讨了水环境因子空间变异产生的原因.结果表明:(1)变异函教选择球状模型和高斯模型拟合水环境因子的变差曲线,从预测误差判断,拟合效果很好,因此,固城湖水环境因子的空同分布图比较真实地反映了固城湖水环境现状;(2)固城湖TN、NH4+-N基本上呈现从南到北逐渐升高的趋势,TN、NH4+-N、SD的空间变异主要是由人类活动引起,水革对TN、NH4+-N的吸收作用、SD的改善作用不明显;(3)太湖区TP基本上呈现从中西部向东逐渐升高的趋势,与大湖区水草密度的变化趋势相反;水革密度越大(大湖中南部)pH越高,而水草密度越小(航道、湖东部)pH越小;(4)中南部湖区围罔的全部拆除、港口河上游生活污水减少,都使得中南部湖区水质得到改善.  相似文献   
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