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211.
212.
Lauren E. Hay Gregory J. McCabe 《Journal of the American Water Resources Association》1998,34(1):103-112
ABSTRACT: Observed April 1 snowpack accumulations within and near the Gunnison River basin in southwestern Colorado are compared with simulations from the Rhea-orographic-precipitation model to determine if the model simulates reliable magnitudes and temporal and spatial variability in winter precipitation for the basin. Twenty simulations of the Rhea model were performed using‘optimal’parameter sets determined for 10-kilometer (km) grids (10-km by 10-km grid cells) through stochastic calibration. Comparisons of Rhea-model simulations of winter precipitation with April 1 snowpack accumulations at 32 snowcourse stations were performed for the years 1972–1990. For most stations and most years the Rhea model reliably simulates the temporal and spatial variability in April 1 snowpack accumulations. However, in general, the Rhea-model underestimates April 1 snowpack accumulations in the Gunnison River basin area, and the underestimation is greatest for locations that receive the largest amount of snow. A significant portion of the error in Rhea-model simulations is due to the calibration of the Rhea model using gauge-catch precipitation measurements which can be as much as 50 percent below actual snowfall accumulations. Additional error in the Rhea-model simulations is a result of the comparison of gridded precipitation values to observed values measured at points. 相似文献
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Miroslava Pozgajova Alica Navratilova Julius Arvay Hana Duranova Anna Trakovicka 《Journal of environmental science and health. Part. B》2020,55(2):166-173
AbstractToxicity of heavy metals to living organisms is a worldwide research topic. Although, much has been discovered about cadmium and nickel impact on biological systems, a lot still remains unclear. We used inductively coupled plasma – optical emission spectroscopy to address the question of the effect of two different heavy metals nickel, and cadmium on intracellular ion balance. Increase or decrease of the content of several essential cations including Ca2+, Na+, K+, Mg2+, Cu2+, Fe3+ in the yeast Schizosaccharomyces pombe was determined. Our results revealed that the cell exposure to high nickel and cadmium concentrations led to significant elevation of Ca2+, Na+, Mg2+, Cu2+, Fe3+ levels in the yeast cell, while the content of K+ decreased. Correlation analyses showing in the presence of nickel and cadmium strong positive correlation among each tested element (Ca2+, Na+, Cu2+, Mg2+ and Fe3+) except for K+, demonstrate the significant impact of heavy metal treatment to ion homeostasis of the cell. Our data indicate that acute nickel and cadmium contamination leads to substantial ionome misbalance in yeast. 相似文献
215.
PM2.5 (particles with aerodynamic diameters less than 2.5 μm) chemical source profiles applicable to speciated emissions inventories and receptor model source apportionment are reported for geological material, motor vehicle exhaust, residential coal (RCC) and wood combustion (RWC), forest fires, geothermal hot springs; and coal-fired power generation units from northwestern Colorado during 1995. Fuels and combustion conditions are similar to those of other communities of the inland western US. Coal-fired power station profiles differed substantially between different units using similar coals, with the major difference being lack of selenium in emissions from the only unit that was equipped with a dry limestone sulfur dioxide (SO2) scrubber. SO2 abundances relative to fine particle mass emissions in power plant emissions were seven to nine times higher than hydrogen sulfide (H2S) abundances from geothermal springs, and one to two orders of magnitude higher than SO2 abundances in RCC emissions, implying that the SO2 abundance is an important marker for primary particle contributions of non-aged coal-fired power station contributions. The sum of organic and elemental carbon ranged from 1% to 10% of fine particle mass in coal-fired power plant emissions, from 5% to 10% in geological material, >50% in forest fire emissions, >60% in RWC emissions, and >95% in RCC and vehicle exhaust emissions. Water-soluble potassium (K+) was most abundant in vegetative burning profiles. K+/K ratios ranged from 0.1 in geological material profiles to 0.9 in vegetative burning emissions, confirming previous observations that soluble potassium is a good marker for vegetative burning. 相似文献
216.
Distribution of endocrine disruptors in the Llobregat River basin (Catalonia, NE Spain) 总被引:9,自引:0,他引:9
The Llobregat basin is a Mediterranean fluvial system with major agricultural, urban and industrial impacts. We combined chemical quantification by liquid chromatography–mass spectrometry with electrospray interface (LC-ESI-MS) and the recombinant yeast assay (RYA) assays to estimate the loads of endocrine disrupting compounds (EDCs) along the basin. Chemical analysis revealed maximum concentrations (at μg l−1 level) of alkylphenols at the lower course of the Llobregat River, which correlated with high levels of estrogenic activity detected by RYA. Analysis by RYA and LC-ESI-MS of influent and effluent waters from four sewage treatment plants (STP) discharging into the basin showed the removal of 80–95% of EDCs by STP treatment. Chemical analysis data and RYA data showed a quasi-linear correlation, demonstrating the complementariness of both methods. Our data suggest that the concentrations of the analysed compounds were enough to explain the total estrogenicity of water and STP samples from the Llobregat basin. 相似文献
217.
自然资源资产负债表编制设计及应用Ⅱ:应用 总被引:3,自引:1,他引:2
根据作者在《自然资源资产负债表编制设计及应用Ⅰ:设计》中提出的自然资源资产负债表设计方案,论文以湖北省十堰市竹溪县为例,采用统计、市场价格法、替代市场法、意愿评估法等分别编制实物量表和价值量表,在此基础上分析自然资源变化与区域经济发展之间的关系。主要结论如下:1)竹溪县林木和特色资源总量呈逐年上升趋势;水资源中工业用水量逐年减少,工业用水效率不断提高,居民生活用水基本保持不变,城镇公共环境和生态环境用水逐年增加,农业发展受降水等自然条件影响较大,今后应进一步发展现代农业,提高农业用水效率。另外,土地资源有不断向建筑用地转变的趋势,未来竹溪县政府应控制建筑用地面积在合理范围内。2)竹溪县自然资源价值处于一个相对稳定的状态。4种资源中,土地资源价值量最高。人为因素对林木资源价值的影响值均为正值,且绝对值不断增加,人为因素对水资源价值的影响值为负值。3)随着竹溪县GDP增加,自然资源总量保持相对稳定,且每年人为原因对自然资源总价值的影响都是正效应。 相似文献
218.
通过对浑河流域沈抚段水体样品和主要污染源样品采集及检测,结合氮氧双稳定同位素及SIAR模型,统计分析研究区域氮素污染现状及氮素污染来源,绘制典型污染源的δ15N、δ18O特征分布图并估算其贡献率,准确追踪和定量外来性氮,从而更好地控制进入浑河流域的氮负荷.结果表明,浑河流域沈抚段受排污口、支流输入、工业废水的影响较大,氮素污染严重.研究区域δ15N值在-5.23‰~33.8‰范围内波动,δ18O值变化范围较大,为-4.12‰~61.54‰.工业废水对氮素贡献率为20.6%~96.3%,贡献率最高,其次是生活污水与粪便、化学肥料、土壤,贡献率分布范围分别为0.3%~29.4%、1.2%~33.5%、1.7%~30.1%,大气沉降对氮素贡献率最低,为0~7.2%.考虑大气污染及污废水排放规律能更准确的确定氮素的污染来源. 相似文献
219.
分别在2013年春季3月23日~3月29日和冬季12月15日~12月21日对兰州市主城区5个采样点进行采样,每天每个采样点采集8个样品,共采集有效样品560个.通过实验室分析和重金属健康风险评价,结果显示:兰州市主城区≤ 10μm颗粒物中,主要分布在5.8~10.0μm (春、冬季)、1.1~3.3μm (春季)和0.65~3.3μm (冬季)范围内,Pb在PM3.3~4.7(一级支气管)中的质量浓度最大,分别为0.2352ug/m3(春季)和0.2177ug/m3(冬季),Cd作为一种致癌重金属在PM9.0~5.8、PM4.7~1.1均被检出.儿童、成年男性、成年女性的非致癌风险值HZ在春季和冬季分别为0.842、0.360、0.345和0.842、0.326、0.361,低于1不存在非致癌的风险,致癌风险值RIS在10-6~10-4的范围内,不存在致癌风险,但儿童RIS值较高,对儿童的健康状况的影响,应受到社会群体的重视. 相似文献
220.
为了解深圳地区黑碳气溶胶(BC)的污染特征,使用深圳市西涌(XC)站点(郊区)和竹子林(ZZL)站点(城区)2014年1月1日~2015年6月30日测得的BC浓度及常规气象资料,对比研究了深圳地区两个不同代表性站点的BC变化特征.结果表明:在观测期间,郊区XC和城区ZZL站点BC小时平均浓度分别为(1.12±0.90),(2.58±2.00)μg/m3,本底浓度分别为(0.27±1.31),(1.07±0.85)μg/m3,气溶胶吸收系数σabs分别为(5.87±4.81),(13.47±10.50) Mm-1,城区站点值均高于郊区站点.两站点BC浓度分布均为对数正态分布,且都呈现干季高、湿季低的季节变化特点.日变化分析表明ZZL站点BC浓度呈现明显的双峰结构,XC站点日变化不明显.通过计算两地的气溶胶波长吸收指数AAE值,发现两地AAE值均接近1,说明两地BC污染主要来源于化石燃料的燃烧.进一步分析可知XC站点西北方向32km处是世界第三大集装箱码头,当西北风达到一定程度时(10~20m/s),码头排放的污染物将严重影响XC站点的BC浓度.后向轨迹聚类分析结果表明,XC站点主要受中远距离输送影响,ZZL站点主要受周边及本地污染源排放影响. 相似文献