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881.
Environmental Science and Pollution Research - Previous studies have reported that daily average temperature is connected with respiratory diseases (RD), but proof is limited for the influence of...  相似文献   
882.
Environmental Science and Pollution Research - An increasing number of studies investigated the association between air pollution during pregnancy and the risk of eczema in offspring. However, no...  相似文献   
883.
Environmental Science and Pollution Research - To comprehensively understand the toxic risks of phthalates to aquatic ecosystems, we examined the acute toxicity of di-(2-ethylhexyl) phthalate...  相似文献   
884.
PROBLEM: Increasingly, investigators are asking youth to self-report daily activity patterns and health outcomes in diary studies. This study assesses recordkeeping fatigue with respect to data quality and event reporting among youth participating in a health diary study. METHOD: Unintentional injury data were collected during a 13-week longitudinal diary study of Ohio youth exposed to agricultural hazards. Two analyses were conducted using data from 2000. Analysis 1 examined trends in discernable recordkeeping errors (DREs) over the course of follow-up. Analysis 2 assessed trends in injury reporting over follow-up. RESULTS: The percentage of items containing a DRE showed a slight, non-significant decline throughout follow-up. Injury reporting declined significantly (p<0.001) over follow-up. SUMMARY: There was no compelling evidence of respondent fatigue with respect to DREs. The observed decline in injury reporting is problematic because estimates of youth injury incidence in health diary studies may vary depending upon the length of the follow-up period.  相似文献   
885.
茅坪河流域非点源污染负荷模拟   总被引:13,自引:1,他引:12  
许其功  刘鸿亮  沈珍瑶  冒亚明 《环境科学》2006,27(11):2176-2181
为定量化研究茅坪河流域农业非点源营养物质氮、磷的输出负荷,在茅坪河的亚流域陈家冲,利用2004-05~2004-10降雨期的监测数据,通过实测值和模拟值的比较对非点源污染模型SWAT(Soil and Water Assessment Tool)进行了率定和验证,采用Nash-Sutcliffe系数(R2)、均方根差(RMSE)和相对误差(CV)检验实测值和模拟值的拟合度.利用验证后的模型模拟了茅坪河流域营养物质氮、磷的输出负荷量.经验证径流、总氮和总磷的Nash-Sutcliffe系数分别为0.71、0.51和0.62,最小相对误差分别为1.8%、1.1%和10%,模型对氮和磷的输出模拟效果稍差,但对径流的模拟取得了较好的效果,表明该模型可运用于茅坪河流域非点源污染的模拟研究.模拟结果显示,2004-05~2004-10,茅坪河流域共有102.5 t氮和9.46 t磷流入长江,大量农业非点源污染的产生是造成茅坪河水质恶化的重要原因之一.  相似文献   
886.
A previously published data set of HCH isomer concentrations in topsoil samples from Tianjin, China, was subjected to geospatial analysis. Semivariograms were calculated and modeled using geostatistical techniques. Parameters of semivariogram models were analyzed and compared for four HCH isomers. Two-dimensional ordinary block kriging was applied to HCH isomers data set for mapping purposes. Dot maps and gray-scaled raster maps of HCH concentrations were presented based on kriging results. The appropriateness of the kriging procedure for mapping purposes was evaluated based on the kriging errors and kriging variances. It was found that ordinary block kriging can be applied to interpolate HCH concentrations in Tianjin topsoil with acceptable accuracy for mapping purposes.  相似文献   
887.
The potential of 18 different plants to be used in the chemically enhanced phytoextraction of Cu, Pb, Zn and Cd was assessed using pot experiments. Chrysanthemum coronarium L. was the species most sensitive to the application of EDTA, and had the highest enhancement of Cu and Pb concentrations in its shoots. Compared with EDTA, EDDS was more effective in enhancing the concentration of Cu in the shoots of Chrysanthemum coronarium L. and Zea mays L. grown on multi-metal contaminated soils. The EDTA-treated soil still had a significant ability to enhance the concentrations of Cu and Pb in the shoots of Zea mays L. six months after the chelant treatment. However, the EDDS-treated soil did not have any effect in enhancing the concentrations of metals in the shoots of Zea mays L. in the second crop test. The results may indicate that EDDS biodegrades more rapidly than EDTA in soil and is better in limiting potential metal leaching.  相似文献   
888.
889.
浅谈我国环保产业现状及发展方向   总被引:2,自引:0,他引:2  
随着全球经济的进一步增长及生态环境的急剧恶化,环保产业的发展速度将远远超过其他行业。在世界环保产业市场的角逐中发达国家占有绝对的优势。我国环保产业跻身国际市场,首先要解决技术起点低,实力差的问题,并要扩大生产规模,走集约化经营道路,加大环保产业投入,选择好环境技术、设备的出口市场。  相似文献   
890.
文章论述了城市生态化及其发展对策 ,提出可持续城市发展的概念及其生态原则 ,以期推动我国城市生态化和可持续城市建设工作的开展  相似文献   
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