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901.
Nityananda Mondal Mayalagu Rajkumar Jun Sun Sourav Kundu P. S. Lyla Seyed Ajmal Khan Jean Paul Trilles 《Environmental monitoring and assessment》2010,171(1-4):471-486
The present study about the gammarid amphipods of Vellar and Uppanar estuaries was performed during two seasons (pre-monsoon and post-monsoon, 2005–2006), respectively, in nine habitats: five in the Vellar estuary and four in the Uppanar estuary. Amphipod samples were collected from sediments, oyster beds, seaweeds, sea grass, and mangroves. A total of 29 species of gammarid amphipods were collected in each area. The surface water temperature ranged from 16°C to 26°C, the salinity from 20 to 32 psu, and the pH between 7.5 and 8.3. Dissolved oxygen ranged from 5.3 to 7.8 ml/l. The maximum abundance of amphipods was observed during the pre-monsoon (July to September) in Vellar mangrove, and it was minimum during the pre-monsoon in Uppanar sea grass. It was found that several physicochemical factors, such as salinity, temperature, dissolved oxygen, pH, and the substrate have a marked effect on the distribution and the relative abundance of amphipods. The ranges of species diversity, richness, dominance, and evenness in the Vellar and Uppanar estuaries were 1.58–4.15, 1.82–5.29, 0–0.11, and 0.96–1, respectively. Using multivariate analyses, in each estuary, it was possible to identify different communities of amphipod species according to their habitats. 相似文献
902.
Minghui Xie Li Li Qi Qiao Qihong Sun Tichang Sun 《Journal of Cleaner Production》2011,19(17-18):2100-2106
A Life Cycle Assessment (LCA) approach was used to compare the environmental impacts in the life cycle of two milk packaging systems, PA-PE-Al laminate—a laminated foil made from paper, polyethylene and aluminum foil—and polyethylene. The data for the mass, energy fluxes and environmental emissions were obtained from published literature and from site investigations, for the two systems being analyzed for environmental impacts. The application of LCA using Eco-Indicator 99 has made the comparison of the environmental impacts of the two milk packages possible. The results of this LCA study are discussed and the results reveal that the composite packaging has a slightly higher environmental impact than the plastic one. In addition, the environmental impact of raw material extraction is the highest in all of the life cycle stages except for disposal. The environmental impact of composite packaging mainly comes from the fossil fuels, land use and respiratory inorganics categories, while the plastic packaging mainly comes from the fossil fuels category. However, the composite packaging has a greater environmental impact because it has not been well recycled and reused. This environmental impact could be decreased by developing the technology to separate out polyethylene and aluminum from the packaging. 相似文献
903.
Xu Bentuo Wu Minghong Pan Chenyuan Sun Yan Yuan Debao Tang Liang Xu Gang 《Environmental science and pollution research international》2017,24(16):14409-14416
Environmental Science and Pollution Research - Hydroxylated polyhalodiphenyl ethers (HO-PXDEs) have attracted considerable scientific interest as examples of emerging aquatic pollutants. However, a... 相似文献
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本文根据采自嘉陵江合川江段的483尾标本,研究吻(鱼句)的生长和繁殖力,并对其资源的增殖保护和合理利用提出初步意见。 相似文献
906.
酸沉降是一复杂的大气物理和化学过程,涉及诸多复杂影响因素。目前,我国酸雨湿沉降模式还仅限于模拟云下洗脱成酸过程,而对云中的成酸过程还未进行深入研究,这不仅在理论上不完善,而且更重要是在许多情况下与我省实际情况不符。本课题针对四川省特定的地理,气象特点和严重的大气污染情况,并借鉴国外研究成果,提出了考虑酸性沉降的云中和云下成酸过程和各种影响因素的综合酸雨湿沉降模式,并根据此模式来估算和预测四川省酸雨 相似文献
907.
选择北京市四家锅炉厂的电焊工56名,即从事手把焊、氩弧焊、CO2气体保护焊、电弧气爆等特种工种作业人员。通过调查,提出单项四级评分标准,再依模糊数学模型,进行综合评价。按B=A·R,求得B中最大元为0.707。最后总评为甲级。此结果与权数分配有关。此方法,可为劳动卫生管理(防护措施评级)提供依据。 相似文献
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