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Tsung-Ming Yang Shu-Kai Fan Chihhao Fan Nien-Sheng Hsu 《Environmental monitoring and assessment》2014,186(8):4925-4934
The purpose of this study is to establish a turbidity forecasting model as well as an early-warning system for turbidity management using rainfall records as the input variables. The Taipei Water Source Domain was employed as the study area, and ANOVA analysis showed that the accumulative rainfall records of 1-day Ping-lin, 2-day Ping-lin, 2-day Fei-tsui, 2-day Shi-san-gu, 2-day Tai-pin and 2-day Tong-hou were the six most significant parameters for downstream turbidity development. The artificial neural network model was developed and proven capable of predicting the turbidity concentration in the investigated catchment downstream area. The observed and model-calculated turbidity data were applied to developing the turbidity early-warning system. Using a previously determined turbidity as the threshold, the rainfall criterion, above which the downstream turbidity would possibly exceed this respective threshold turbidity, for the investigated rain gauge stations was determined. An exemplary illustration demonstrated the effectiveness of the proposed turbidity early-warning system as a precautionary alarm of possible significant increase of downstream turbidity. This study is the first report of the establishment of the turbidity early-warning system. Hopefully, this system can be applied to source water turbidity forecasting during storm events and provide a useful reference for subsequent adjustment of drinking water treatment operation. 相似文献
653.
采用环境一号卫星(HJ1A/1B)的多光谱(CCD)数据,通过影像预处理提取巢湖湖域蓝藻的归一化植被指数(NDVI),对巢湖湖域的蓝藻进行动态遥感监测,在GIS平台上计算蓝藻在研究时段内的平均空间分布、模拟其变化趋势及平均改善速度,结果表明,HJ1A/1B-CCD影像数据具有较高时空分辨率,对巢湖湖域蓝藻的识别能力强;巢湖湖域生态环境总体较好,蓝藻只是在局部湖域暴发,其中蓝藻极高密度区、高密度区呈团状、片状,主要集中分布在巢湖西湖区北部沿岸,并且为楔形向中心延伸;巢湖蓝藻暴发的湖域总体呈现改善趋势,但各区改善的程度、速度差异较大,原因复杂,尤其是西湖区北部沿岸不仅改善速度缓、改善程度不佳,甚至出现退化;巢湖西区应以治理为主、监测为重,东区则以着重监测。 相似文献
654.
Shihe Fan Igor Burstyn Ambikaipakan Senthilselvan 《Environmental Modeling and Assessment》2010,15(2):137-146
The provinces of Saskatchewan, Alberta, and British Columbia are major oil- and gas-producing regions in western Canada. With
increasing oil and gas production activities, there has been a growing concern of the effect of oil and gas industry emissions
on health. Nevertheless, lack of proper tools to estimate the exposure to these emissions has been a hindrance to epidemiological
studies and risk assessment. This paper presents a spatiotemporal modeling approach to estimating ambient sulfur dioxide (SO2) levels based on environmental monitoring data (N = 10,295), which were collected at rural sites (591 per month on average) of this region from June 1, 2001 to May 31, 2002.
Based on the model, illustrative maps consistently revealed high and low SO2 concentration sub-regions. The sub-regions with elevated SO2 concentrations had increased levels during the winter months from December 2001 to March 2002 and then decreased during the
spring of 2002. This statistical modeling approach may help researchers estimate the SO2 levels within the study area for their epidemiological studies or risk assessment. 相似文献
655.
废弃农药厂土壤和地下水中有机磷农药的健康风险评价 总被引:3,自引:2,他引:1
采用气相色谱氮磷检测器法测定了某废弃农药厂土壤和地下水中有机磷农药(OPPs)的含量,并用美国环保署(USEPA)推荐的健康风险评价方法,对该场地土壤和地下水中OPPs引起的健康风险进行了初步评价。结果表明,土壤、地下水中∑OPPs的检出浓度范围分别为1.3~1 129μg/kg和48.0~149.2 ng/L,点位检出率分别为73%、100%。土壤和地下水中OPPs的非致癌总风险指数均小于1,致癌总风险指数均在10-4以下。根据USEPA的建议值,初步认为该场地土壤和地下水中OPPs不会对人体产生明显的健康危害。 相似文献
656.
Air pollution is one of the major environmental problems in India, affecting health of thousands of 'urban' residents residing in mega cities. The need of the day is to evolve an 'effective' and 'efficient' air quality management plan (AQMP) encompassing the essential 'key players' and 'stakeholders.' This paper describes the formulation of an AQMP for mega cities like Delhi in India taking into account the aforementioned key 'inputs.' The AQMP formulation methodology is based on past studies of Longhurst et al., (Atmospheric Environment, 30, 3975-3985, 1996); Longhurst & Elsom, ((1997). Air Pollution-II, Vol. 2 (pp. 525-532)) and Beatti et al., (Atmospheric Environment, 35, 1479-1490, 2001). Further, the vulnerability analysis (VA) has been carried out to evaluate the stresses due to air pollution in the study area. The VA has given the vulnerability index (VI) of 'medium to high' and 'low' at urban roadways/intersections and residential areas, respectively. 相似文献
657.
采用单颗粒气溶胶飞行时间质谱仪(Single Particle Aerosol Mass Spectrometer,SPAMS)对西安市大气矿尘颗粒物进行连续12 d在线分析,共采集到107 425个同时含有正负质谱信息的矿尘颗粒,矿尘颗粒物占PM_(2.5)样本数的8.44%。结果表明,矿尘颗粒物的正离子碎片成分以Na~+、K~+、Al~+、Ca~+、CaO~+、Fe~+为主,同时还含有Pb~+等,负离子碎片成分以NO~-_2和NO~-_3为主,另外还含有HSO~-_4、SiO~-_3、HSiO~-_3、H(NO_3)~-_2等。在西安市大气细颗粒物中,矿尘颗粒物中贡献较大的几类(如含钙、含铁、铁氧颗粒物等)大多是老化的成分。将观测阶段采集到的矿尘颗粒纳入本地污染源谱进行来源分析,其主要来源为扬尘源、工业源、燃煤源和汽车尾气源等。 相似文献
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