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Zooplankton are an essential component of the marine and estuarine food chains. The ecotoxicological risk to zooplanktonic communities, estimated through the use of the biomarkers, can be used as an early warning signal of a potential alteration of the ecosystem health. The aim of this project was to evaluate the potential use of several biomarkers (esterases, mixed function oxidases, porphyrins) in zooplanktonic organisms. The acetylcholinesterase activity (AChE) was determined in homogenates of whole organisms of 10 different zooplanktonic crustaceans. Mean activity of AChE was 10.05 micromol/min/g for Acartia margalefi; 3.30 for Acartia latisetosa; 79.70 for Siriella clausi; 49.97 for Diamysis bahirensis; 7.48 for Siriella armata; 14.20 for Mysidopsis gibbosa; 4.49 for Euphausia crystallorophias; 1.66 for Euphausia superba; 2.74 for Streetsia challengeri; 13.26 for Meganycthiphanes norvegica. The species moreover showed a linear increase in enzyme activity in relation to the increase in sample concentration. The key result of this study concerns the different AChE activity basal values of the crustaceans' different species. 相似文献
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Dowty RA Shaffer GP Hester MW Childers GW Campo FM Greene MC 《Marine environmental research》2001,52(3):195-211
Research was conducted to assess the impact of oiling on fresh-marsh plant communities and to test the efficacy of techniques that may be used to enhance the bioremediation of crude oil spills in these environments while minimizing secondary anthropogenic impacts. To emulate field conditions, a mesocosm facility was used that houses 120 mesocosm vessels, each of 200-1 capacity. A five-way factorial treatment arrangement was used that included two substrates (inorganic, organic), two nutrient regimes (fertilized, not fertilized), two aeration levels (substrate aeration, no aeration), three oiling concentrations (0-, 5-, 10-1 m(-2) of South Louisiana Sweet Crude oil), and four vascular plant species (Alternanthera philoxeroides, Panicum hemitomon, Phragmites australis, Sagittaria lancifolia, and an unplanted control). Under the 5- and 10-1 m(-2) oiling concentrations, S. lancifolia displayed a short-term response of increased productivity, whereas P. hemitomon had the highest biomass production and photosynthetic rates at the end of the 18-month experiment. Overall plant growth and productivity, as well as oil degradation, were significantly higher in the inorganic substrate, indicating that biodegradation of oil spills in organic substrates may require a longer time period. Time-released fertilizer also stimulated plant productivity and resulted in higher soil respiratory quotients, suggestive of greater microbial activity, particularly in aerated mesocosms. The amount of oil remaining after 18 months was lowest in aerated and fertilized mesocosms containing either P. hemitomon or S. lancifolia and a substrate of low organic matter content. 相似文献
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本文比较了活性水系沉积物的冻结采样技术与常规采样技术,经统计分析,10种氧化物和21种微量元素在两种技术之间全部都存在着显著的差异。在122个采样点上所得到的氧化物重量百分比和微量元素含量表明:冻结采样可得到具有代表性的沉积物样品。每个采样点为了获得对沉积物中氧化物重量百分比和元素含量具有代表性的评估,需要小于50%的冻结样品,相反,常规采样由于冲洗和淘洗细粒级沉积物,致命用以常规地球化学分析的沉 相似文献
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含金的冰长石-石英集合体是金银矿化的指示剂,它们在区域矿床系列中,并在的集合体的结构,石英及冰长石典型的化学键和金矿堆积作用中,具有统一的规律性。 相似文献
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Marsili L Casini S Bucalossi D Porcelloni S Maltese S Fossi MC 《Marine environmental research》2008,66(1):151-153
The aim of the present study was to propose the immunofluorescence technique in cultured fibroblasts from Mediterranean cetaceans as a new "in vitro" tool to explore the susceptibility of these marine mammals to different xenobiotic compounds. The cell lines were cultured from integument biopsies of free-ranging and stranded cetaceans (dead within 12h). Using the indirect immunofluorescence assay, we detected endogenous proteins induced by different contaminants. Here we present the method used for qualitative and quantitative evaluation of cytochromes P450 (CYP1A1 and CYP2B) induced by some POPs (DDTs and PCBs) and emerging contaminants (PBDEs) in fibroblast cell cultures of striped dolphin (Stenella coeruleoalba) and bottlenose dolphin (Tursiops truncatus). Immunofluorescence was quantified with a specially designed Olympus macro, DetectIntZ. A major result was the possibility of using this "in vitro" assay to quantify induction of endogenous proteins. 相似文献
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综合性与区域性是地理学的两大基本特点。随着区域发展成为人们关注的热点,跨学科综合研究成为学科发展趋势,我国的区域综合研究势在必行。我国地理学的发展历程和当今研究现状亟须区域综合研究的根本性突破,才能更好地为全球层面上的全球环境变化、国家层面上的可持续发展以及地区层面上的社会经济发展服务,才能推动地理学理论创新,真正实现黄秉维先生所倡导的"综合指导下分析,分析基础上综合"的方法论应用。最后,依据我国地域特征,拟定8个典型区域作为近期综合研究区,并提出加快研究云贵高原喀斯特地区的倡议。 相似文献
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