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921.
Twenty two diversity, evenness and dominance indices based on phytoplankton community structure were examined for their sensitivity to assess eutrophic conditions. Data from two sampling sites, one eutrophic and one oligotrophic, were used as reference data-sets for evaluating the indices. McNaughton's dominance index, cell number, species number (Hill's N0), Kothe's species deficit, Odum's species per thousand individuals and Evenness E2, E3 seemed to be the most sensitive indices for discriminating between eutrophic and oligotrophic conditions. A case study was also performed using a data-set from ten stations spaced along the coastal area of the city of Rhodes, Aegean Sea, Greece to find out which of the indices were appropriate to assess different levels of eutrophication. Kothe's species deficit, Hill's N0 (species number), Margalef's and Gleason's indices have shown the highest sensitivity to resolve oligotrophic, mesotrophic and eutrophic conditions. 相似文献
922.
地理信息系统在近岸海域环境管理中的应用 总被引:4,自引:0,他引:4
文章研究了地理信息系统技术在某滨海城市近岸海域环境管理中的应用 ,研究表明在地理信息系统支持下的近岸海域环境管理包括 :海洋污染源管理、海洋环境质量评价等 ,具有界面友好、形象直观、使用方便、易于操作和维护等优点。 相似文献
923.
Since 1986, when green oysters occurred due to the copper and organic pollution in the Charting coastal area, the government banned all maricultural activity. It has been claimed that growing algae in a polluted environment may clean the water of pollutants and restore the marine ecosystem. to test this hypothesis, in the Charting coastal area a three-year programme (from August 1992 to July 1995) was carried out. the survey programme included environmental components such as salinity, temperature, pH, dissolved oxygen, biological oxygen demand (BOD), particulate organic carbon (POC), heavy metals and ecological indicators such as nutrients, chlorophyll-a, primary productivity. in the first year study, the environmental background data collected was used to select the suitable season and locations for growing large algae transferred from the laboratory to the field study area. Since September 1993, various species of large algae have been cultured. Although some of the growing algae were damaged by a typhoon in August 1994, the impact of the growing algae on the environmental conditions in the area has been monitored throughout. Elsewhere, we have reported that in the algae growing area higher dissolved oxygen with lower values of BOD and POC were found, and the concentrations of heavy metals in both water and sediments decreased. the purpose of this paper is to evaluate the possible impact of growing large algae on the ecological conditions in Charting coastal waters through the period from August 1983 to May 1995. As a result of the positive results obtained, large amounts of algae have again been cultured in the same area during the period from April 29 to May 25, 1995. We expect that inorganic and organic pollutants will be reduced by the algal growth, oyster mariculture will be restored and finally, the fishery resources potential will be increased. 相似文献
924.
郝艳萍 《中国人口.资源与环境》2002,(5)
随着沿海经济和海洋开发活动的快速发展 ,海洋环保问题日益突出 ,海洋环保产业有望成为新的经济增长点。本文论述了发展海洋环保产业的必要性 ,界定了海洋环保技术及其产业的内涵 ,概述了我国海洋环保技术和产业的发展现状 ,并提出了发展我国海洋环保产业的建议 相似文献
925.
Some polymeric marine coatings based on vinylcopolymer and linseed oil have been prepared in the laboratory and their efffect on phytoplankton standing crop was tested. the coating is prepared either from vinylcopolymer or linseed oil or a mixture of both binders with 1:1, 1:2 and 2:1 ratios in the presence or absence of a soluble resin. the coatings were applied to glass slides and tested in a sea water medium. Also, correlations between the weight of the coating film and numbers of phytoplankton species were calculated. the results showed no correlation between the weight of films of either vinylite or oil binders and the total number of all phytoplankton species, but significant correlation was found for some phytoplankton species, such as Thalassiosira decipiens. the weight of the film coating of vinylcopolymer in the presence of soluble resin with 1:1, 1:2 and 2:1 ratios is significantly correlated to the total number of phytoplankton and some other dominant species. Formulations of linseed oil and a soluble resin with 1:1, 1:2 and 2:1 ratios are correlated to the numbers of Chaetoceros affinis, Bellorochea malleus and Skeletonema costatum. 相似文献
926.
927.
鼠李糖脂对不同菌株降解柴油污染物的影响 总被引:1,自引:0,他引:1
通过一系列实验分析了鼠李糖脂对柴油污染物生物降解的影响。单菌株柴油降解实验结果表明,在添加生物表面活性剂鼠李糖脂后,各菌株细胞表面疏水性均发生不同程度的增加,并且对柴油的降解率均有所提高。在混合菌的柴油污染物降解实验中,发现当向土壤中添加了200 mg/L鼠李糖脂时,对柴油的降解才有较大的提高;而当添加100 mg/L的鼠李糖脂到水体中时,对柴油的降解就有较大的提高,而当鼠李糖脂浓度提高为200 mg/L时,柴油的降解率却没有进一步明显的提高。这说明鼠李糖脂对柴油降解的影响程度不仅与环境介质有关,还与添加的鼠李糖脂浓度有关。进一步分析表明,添加适当浓度的鼠李糖脂不仅可以提高对柴油的降解率,而且可加速其降解速度,缩短生物修复所需时间。 相似文献
928.
929.
Abstract: An increased number of tourists viewing animals in the wild have increased stress on these animals (hereafter wildlife). Many wildlife‐viewing locations rely on voluntary compliance with posted regulations to protect animals from tourists because of the expense of employing on‐site enforcement personnel. Voluntary compliance, however, is ineffective. The presence of official‐looking volunteers may decrease the incidence of wildlife harassment by tourists. To test this possibility, we observed tourists interacting with 5‐ to 12‐month‐old New Zealand fur seals (Arctocephalus forsteri) at the popular Ohau Stream waterfall while in the absence or presence of a young woman in plain sight wearing a neon vest (i.e., observer) and when an observer was not present. We observed 254 tourist groups at the waterfall when young seals were present. The percentage of groups in which at least one person harassed (approached, touched, or threw objects) a young seal was two‐thirds lower when the official‐looking observer was present. Frequency of harassment was inversely related to observer presence. Programs in which volunteers work at tourist sites are popular in countries with high tourism rates, such as New Zealand. Our results show that a relatively inexpensive and effective tourism‐management strategy may be to post such volunteers as observers at sites where tourists view wildlife. 相似文献
930.
一种水基燃烧新技术及其清除海洋油污应用 总被引:1,自引:0,他引:1
针对大面积海洋石油污染难以利用现有方法进行高效治理的问题,针对性地提出了一种简便实用的水基燃烧新技术,介绍了其技术特点和以碳化钙和金属钾为主要原料配方的化学反应原理,进而利用其独特的可长时间持续燃烧这一关键性能,设计开展了对海洋油污进行清除处理的实验研究。结果不仅表明了采用该技术处理海洋油污的有效性,特别是对实际最为常见且采用传统燃烧法根本无法处理的油层厚度不足3 mm的海洋原油污染,通过其对油层持续的点火和加热挥发等多种作用也可达到高效清除的目的,并从油层厚度与燃烧状况之间的关系对相关的理论问题进行了分析,体现了其良好的应用前景。 相似文献