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The Royal Military College of Canada, located on the north eastern shore of Lake Ontario, possesses an abundance of copper roofs
and lacks surface water treatment prior to discharge into Lake Ontario. Rainwater, roof runoff and soil samples were collected and
analyzed for copper and other parameters. Copper was consistently detected in runoff samples with average concentrations of 3200 2100 g/L. Multivariable linear regression analysis for a dependant copper runoff concentration yielded an adjusted R2 value of 0.611,
based on an independent variable model using minimum temperature, maximum temperature, total precipitation, and wind speed. Lake
water samples taken in the vicinity of storm water outfalls draining areas with copper roofs ranged from 2.0 to 40 g/L copper. Such
data exceed the 2.0 g/L Canadian Water Quality Guidelines for the Protection of Aquatic Life as outlined by the Canadian Council of
Ministers of the Environment (CCME). Analysis of raw, filtered and digested forms suggested that the majority of copper present in
runoff and lake water samples was in a dissolved form. The majority of soils taken in this study displayed copper concentrations below
the 63 g/g CCME residential/parkland land use limits. These findings suggested that ion exchange processes between runoff water and
soil do not occur to a sufficient extent to elevate copper levels in soil. It may therefore be concluded that the eventual fate of copper,
which is not discharged via storm water outfalls, is lost to the water table and Lake Ontario through the sub-soil. 相似文献
883.
Estrogenic effects of water from the Yangtze River (Nanjing section) on goldfish (Carassius auratus) after an early life stage exposure 总被引:1,自引:0,他引:1
Effects of river water from the Yangtze River (Nanjing section) on fish development, vitellogenin (VTG) induction, gonado-somatic
index (GSI) and sex ratio were investigated by exposing goldfish (Carassius auratus) in the early life stage (from fertilization to 28 days
post-hatch) to water samples (25%, 50% and 100%) collected from three representative sections. The results showed that there was no
significant effect on hatching success for any of the exposure groups, but survival was significantly reduced when compared with the
control (P < 0.05). Body lengths, weights of all treated fish did not differ significantly from those of the control. Condition factors (CF)
of larval fish exposed to 50% and 100% river water from the Jiangxinzhou section and 100% river water from the Daqiao section were
significantly lower than that of the control (P< 0.05). VTG inductions were significant in larval fish exposed to all the dilution series
of river water. No significant difference in CF value was observed in any exposure group after 150 days of depuration. VTG was fully
eliminated after 75 days of depuration. For both female and male, GSI did not significantly differ between exposure groups and the
control after 150 days of convalescence. The highest female:male ratios were observed in response to the treatment with 50% or 100%
river water from the Jiangxinzhou section and 100% river water from the Daqiao section (53:47, 56:44 and 54:46, respectively), but no
significant difference in sex ratio was observed in any treated group when compared to the control. The results showed that early life
stage exposure of river water from the Yangtze River (Nanjing section) had adverse effects on goldfish development and reproductive
health, and the effects on CF and VTG were reversible after depuration in clean water. 相似文献
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建筑能耗是重要的社会能源消耗主体。采用宏观能源统计方法,利用综合能源平衡表估算上海市1999-2009年住宅能耗和公共建筑运行能耗的变化及其特征。结果表明,上海市民用建筑总能耗由1999年的687.82万tce增加到2009年的1 774.91万tce,平均年增长率为4.68%;住宅建筑能耗呈上升趋势,而单位面积能耗逐年下降,单位面积住宅建筑能耗均值比公共建筑低35.30 kgce/(m2.a);公共建筑单位建筑面积能耗变化呈略增态势,2009年单位建筑能耗比1999年高9.64 kgce/(m2.a)。研究结果可为建筑节能减排政策的制定提供决策参考和数据支持。 相似文献
889.
温州市不同功能区地表径流污染特征研究 总被引:1,自引:0,他引:1
以温州市城区为例,在多雨季节对商业区、工业区、居民区、交通路面、绿地等五大功能区的降雨径流水质进行了6次采样监测,发现不同功能区地表径流水质差异较大。前10 min初期径流中各功能区COD、TN;商业区和工业区的NH4+-N;商业区、交通路面和工业区TP的平均浓度均劣于地表水V类水质标准。随着降雨历时的延长,降雨径流中主要污染物浓度逐渐下降,并在30~45 min趋于稳定。对COD而言,由商业区造成的径流年污染负荷最高,达5 763.15 t/a;对SS而言,温州市几个重要工业经济开发区所造成的径流年污染负荷最为严重,达到15 883.67 t/a,居民区次之,达11 804.81 t/a;对NH4+-N而言,由工业区、商业区和居民区所造成的径流污染相对较重,分别在50 t/a左右。地表径流对温瑞塘河的COD贡献较大,达22.88%;而由地表径流所引起的NH4+-N和TP污染对温瑞塘河的污染贡献较小。 相似文献
890.
基于不确定度和敏感度分析的LCA数据质量评估与控制方法 总被引:6,自引:1,他引:5
通过提出定量评估并控制LCA数据质量的系统化方法(称为CLCD-Q方法),从LCA案例的原始数据和清单数据算法开始评估不确定度;然后通过两次蒙特卡罗模拟,先后得出单元过程清单数据及LCA结果的不确定度;最后结合敏感度分析,辨识出LCA模型中具有高不确定度和高敏感度的关键数据,从而指出控制和改进数据质量的关键点.结果发现,上述方法可在eBalance软件和CLCD数据库中实现.同时,对中国电网电力生命周期的示例研究表明,上述方法将传统的LCA数据质量评估延伸到了原始数据层面,从而为数据收集过程中的原始数据与算法选择提供了直接的支持,同时也可以针对数据质量不达标的LCA结果,指出最有效的改进方向. 相似文献