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11.
Although the Yellow River Delta and Bohai Sea coastal zone are long distance and different environment with Po River Delta and Adriatic Sea coastal zone, the comparison of data of two different areas and the evolution trend of two areas are quite similar. The influence of natural climatic changes on the evolution of the deltas and coastal zones exists both in ancient and modern times. The cold/wet period occurred in 1300—1400A. D. and 1550 —1850 A.D. within this"large scale" climatie cycle, and shorter periods (10— 35 years) of cold rainy weather alternated with warm/dry period are known as "Bruckner cycles" which have influence on the evolution of the deltas and coastal zones. 相似文献
12.
Abbondanzi F Campisi T Focanti M Guerra R Iacondini A 《Marine environmental research》2005,59(5):419-434
A study was conducted to determine polycyclic aromatic hydrocarbons (PAHs) distribution and microbial population changes in brackish sediments from an Italian lagoon included in the Ramsar List of Wetlands of International Importance. The presence and level of PAH-degrading bacteria were estimated by the most probable number (MPN) enumeration technique, whereas degradation capability towards target compounds was checked against loss of spiked PAHs (Phenanthrene, Anthracene and Fluoranthene) in MPN tubes after incubation in optimal conditions. Chemical analyses and microbiological counts suggested a potential for PAHs biodegradation by natural occurring populations of sediment microorganisms, thus indicating an "optimal range" in sediment PAHs concentrations, outside of which the natural selection of the indigenous microflora did not occur. The MPN procedure here described, provided an effective and reliable way to simultaneously determine microbial population densities and subsequent confirmation of the biodegradation capability of sediment indigenous microflora when exposed to laboratory and environmental concentrations of PAHs. 相似文献
13.
海洋地热流探测对海洋油气资源远景评价和构造地质研究具有十分重要的意义,在海洋科学研究中日益受到重视。本文详细分析了海洋地热流测量的基本原理,系统介绍了海洋地热流测量常用的布拉得型探针和艾文型探针的工作方式和测量方法,从加强理论研究、减小测量误差、提高测量效率及监控技术研究等方面提出了海洋地热流测量的发展方向。 相似文献
14.
Regoli F Nigro M Chierici E Cerrano C Schiapparelli S Totti C Bavestrello G 《Marine environmental research》2004,58(2-5):637-640
The role of endosymbiotic diatoms as pro-oxidant stressors in porifera has been investigated in the Antarctic sponge Haliclona dancoi in which the presence of diatoms is influenced by marked seasonal variations during the austral summer. Both chlorophaeopigments and frustules were absent in sponge tissues sampled in early November at the beginning of the summer and increased from the mid of December with slightly shifted temporal trends. The efficiency of antioxidant defenses in the sponge showed a marked response to symbionts with clearly enhanced values corresponding to the peak of diatoms. 相似文献
15.
Akcha F Tanguy A Leday G Pelluhet L Budzinski H Chiffoleau JF 《Marine environmental research》2004,58(2-5):753-756
DNA single-strand breaks were measured by the comet assay in both gill and hemolymph cells of mussels collected in 3 sampling areas of the French coast (Pointe du Castelli, Pen Bron and Saint-Nazaire Harbour). Whole mussel tissue samples were also collected for the chemical determination of PAH, PCB and heavy metal concentrations. In mussel, a higher level of DNA strand breaks was measured in gill than in hemolymph cells (p < 0.01). Despite a factor of contamination from 2 to 3 between sites, no difference in the extent of mussel DNA strand breaks was shown between sampling locations (p > 0.05), questioning the sensitivity of the assays used in biomonitoring studies. 相似文献
16.
Regoli F Gorbi S Frenzilli G Nigro M Corsi I Focardi S Winston GW 《Marine environmental research》2002,54(3-5):419-423
An integrate approach will be discussed for investigations on oxidative stress in xenobiotic toxicity. While the analysis of individual antioxidants is useful for their sensitivity and to understand the mode of action of a stressor, the integration with the analysis of the total antioxidant capacity provides a more holistic assessment of the overall biological significance of such variations. TOSC has a greater predictive value on the health condition of the organisms and allows to discriminate the different role of specific ROS in oxidative stress syndrome. 相似文献
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南海珠江口盆地贝壳砂土力学性质初步研究 总被引:1,自引:0,他引:1
通过对珠江口盆地广布的贝壳砂的化学组分、粒度组分、形成时代的研究以及对砂土进行直剪试验、主高压结试验、常规三轴剪切试验和动三轴试验,对贝壳砂的土力学性质及动载荷作用下的稳定性作了初步分析,获取了贝壳砂的基本物理力学参数并评价了地震作用下砂土液化的可能性,为海洋工程的设计和施工提供了基本的物理力学参数。 相似文献
20.
以酪蛋白和明胶为蛋白源 ,添加豆油、鱼油、糊精、纤维素以及适量的维生素和矿物质混合剂配制试验饲料 ,饲料配成5个蛋白质水平 ,每个蛋白水平分别包括5个能量级 ,以体质量增长倍数、蛋白质效率和饲料系数为评判依据 ,对体质量为8.73g±0.79g的中华鲟(Acipensersinensis)的适宜蛋白质含量及其蛋白能量比进行了研究。经过为期8周的试验 ,结果表明 :中华鲟幼鲟配合饲料中的适宜蛋白质含量范围为35.7%~41.8% ,饲料的最佳蛋白能量比范围为21.85~30.05ng/J。当试验饲料蛋白质含量为40.3% ,蛋白能量比为27.85ng/J时 ,试验鲟鱼获得最大体质量增长倍数为11.60±1.20,最低的饲料系数为1.68±0.23,以及最高的蛋白质效率为1.58%±0.14%。 相似文献