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1.
公路设计中的环境保护工作   总被引:1,自引:0,他引:1  
阐述了公路建设中环境保护工作的意义,提出在公路工程勘察设计工作中对环境保护的典型作法和取得的效果。  相似文献   
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海河下游水体中DO与NH_3-N、COD_(Mn)相关关系探讨   总被引:2,自引:0,他引:2  
本文应用近年来海河下游监测数据对DO与NH3N和CODMn进行一元线性回归,得到两回归方程:NH3N=-128DO+1054;CODMn=-113DO+1692。并经相关系数和回归系数显著性检验,表明在999%的置信水平下DO与NH3N和CODMn线性相关均极其显著  相似文献   
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Exposure to lead (Pb) may affect adversely human health. Mapping soil Pb contents is essential to obtain a quantitative estimate of potential risk of Pb contamination. The main aim of this paper was to determine the soil Pb concentrations in the urban and peri-urban area of Cosenza–Rende to map their spatial distribution and assess the probability that soil Pb concentration exceeds a critical threshold that might cause concern for human health. Samples were collected at 149 locations from residual and non-residual topsoil in gardens, parks, flower-beds, and agricultural fields. Fine earth fraction of soil samples was analyzed by X-ray Fluorescence spectrometry. Stochastic images generated by the sequential Gaussian simulation were jointly combined to calculate the probability of exceeding the critical threshold that could be used to delineate the potentially risky areas. Results showed areas in which Pb concentration values were higher to the Italian regulatory values. These polluted areas were quite large and likely, they could create a significant health risk for human beings and vegetation in the near future. The results demonstrated that the proposed approach can be used to study soil contamination to produce geochemical maps, and identify hot-spot areas for soil Pb concentration.  相似文献   
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The principal aim of this study was to define and apply a procedure based on a structured questionnaire survey useful to analyze the people’s environmental knowledge in order to select the areas and age groups with a low level of knowledge in a municipality (in Southern Italy) and, therefore, suggest a specific educational campaign for each. The detailed sampling procedure made it possible to carry out a meticulous statistical analysis of the results. The youngest and oldest people showed the lowest level of awareness for each district. A high level of education did not necessarily imply a high level of environmental awareness as well as a greater acceptance of MSW facilities. The satisfaction level of the recycling program was higher amongst the oldest age group. All the citizens in the several areas were unanimous in pointing out the presence of dirt in the street as the main shortcoming of the bring separate collection program. Only the youngest age group self-criticised, considering that they revealed a low level of participation to the separate collection program. While, the oldest people retaining them less influential, claimed that the citizens were not responsible for the failure of the separate collection program. The prevailing opinion of the sample was that people protested against the construction of waste facilities because they were not well-informed, with the most significant opinion of all the age subdivisions being that incineration is a hazardous treatment. The presence of criminal organizations was indicated as the main reason why the Campania Region suffers a serious solid waste emergency. While, the percentage of people pointing their finger at politicians increases with the average age of the respondents with there being a very strong correlation (r2 = 0.9903).  相似文献   
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Environmental Geochemistry and Health - The results of a large geochemical study on various environmental media (soil, stream sediment, groundwater, surface water, lettuce and human hair) of the...  相似文献   
9.
Adult male fathead minnow were exposed for 14 or 28-days under flow-through conditions to undiluted filtered water samples from the rivers Meuse and Rhine in the Netherlands. The experiment included two vessels per treatment each containing 10 fish and samples of five fish were taken after 14 and 28 days. Additional groups were exposed to 17alpha-ethinylestradiol (EE2) as a reference and untreated drinking water as a negative control. Major endpoints examined included induction of vitellogenin (VTG) synthesis, VTG mRNA activity, hepato- and gonadosomatic indices (HSI and GSI) and gonadal histology. No significant difference was recorded in body weight or mean GSI values between the various treatments. Only exposure to Meuse water resulted in significantly higher HSI means after 14 days. Histological examination showed no apparent effects on gonadal tissue except for eosinophilic blood plasma in fish exposed to Meuse water or EE2. After 14 and 28 days, elevated VTG and VTG mRNA levels were measured in most livers of the fish exposed to Meuse water, but not in the fish exposed to Rhine water. This was confirmed by measuring estrogenic responses in the in vitro ER CALUX assay. Induction of VTG synthesis proved to be the most sensitive endpoint in the Non Spawning Male Fish Assay for in vivo detection of bio-available estrogenic activity supplementary to a sensitive in vitro assay. The other endpoints examined varied too much and required a higher number of fish or replicates to achieve sufficient power for statistical testing making them less animal friendly.  相似文献   
10.
Quercus ilex L. leaves were collected four times in one year at six urban sites and one remote area in order to determine trace element and PAH accumulation through concomitant analyses of unwashed and water-washed leaves. Both unwashed and washed leaves showed the highest amounts of trace elements and PAHs in the urban area. Unwashed leaves showed greater differences between urban and remote areas and among the urban sites than washed leaves for trace element and PAH concentrations. Water-washing resulted in a significant (P<0.001) decrease in leaf concentrations of Cr, Cu, Fe, Pb, V and Zn. By contrast, Cd and total PAH concentrations showed no differences between unwashed and washed leaves.  相似文献   
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