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招远近岸人工鱼礁集聚经济生物资源效果的初步研究
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作者 焦金菊 邱盛尧 杨宝清 《齐鲁渔业》 2009年第1期3-5,共3页
2008年4月采用Video Ray ProⅢXE水下机器人对招远市辛庄镇近岸-10m等深线内建设2年的人工鱼礁区和3处本底对照海域进行拍摄调查,研究人工鱼礁集聚经济生物资源的效果。调查结果显示,沙质本底海域,仅分布有少量的脉红螺,密度为0.097 ind... 2008年4月采用Video Ray ProⅢXE水下机器人对招远市辛庄镇近岸-10m等深线内建设2年的人工鱼礁区和3处本底对照海域进行拍摄调查,研究人工鱼礁集聚经济生物资源的效果。调查结果显示,沙质本底海域,仅分布有少量的脉红螺,密度为0.097 ind/m^2;带有少量石块的沙质本底海域,无刺参分布,仅仅发现少量褶牡蛎和脉红螺,密度分别为0.14和0.30ind/m^2;自然岩礁本底海域,有少量的刺参、褶牡蛎和脉红螺分布,密度分别为0.28、35.33和0.36ind/m^2,同时还发现有许氏平鲉、长蛸和日本(虫寻),密度分别为0.05、0.02和0.02ind/m^2。建设2年后的人工鱼礁区内经济生物资源数量明显提高,其中刺参和褶牡蛎增加最为明显,密度分别达到1.20和869.23 ind/m^2;脉红螺也有明显增多,密度1.33 ind/m^2。人工鱼礁建设对海域经济生物资源的集聚起到重要的作用。 展开更多
关键词 人工鱼礁 经济生物资源 招远近岸海域
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Economic Competition for High Profits from Antarctic Living Resources in Their Protection Area
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作者 Ryszard Jacek Traczyk 《Journal of Environmental Science and Engineering(A)》 2016年第1期1-58,共58页
Since 1790, Antarctic living resources were becoming subjects of competition among the exploiters to be first in obtaining the maximum profit from them. This led to subsequent extinction of valuable species from fur s... Since 1790, Antarctic living resources were becoming subjects of competition among the exploiters to be first in obtaining the maximum profit from them. This led to subsequent extinction of valuable species from fur seals and next penguins, large through small whales, industrial demersal fish, further to pelagic species and now toothfish, crabs and krill. Catch proportions of their numerous and biomass decrease. The biomass of South Georgia Icefish estimated for 40 years in spide of decreasing trend has one of the largest components-the oscillations with periods of 3 years or 4 years. Their models explain large biomass fluctuations in the years 1975 to 1981 with amplitudes ±15 × 10^3 tonnes around average 20 ×10^3 tonnes and further decline up to 2005 season with oscillation ±4 ×10^3 tonnes around average 5 × 10^3 tonnes. For future season, 2016 model predicts a little increase of the biomass oscillation at level of 8 × 10^3 tonnes with reduced amplitude 2 × 10^3 tonnes. Slowly increase density of adult fish was also reported for target similar and close related mackerel icefish. Additional references for biomass levels help reduce the risk of further depletion biomass of Pseudochaenichthys georgianus which already declined to 75%. As global warming promote phytoplankton growth, replacing krill fishery by algae farms can save unique Antarctic heritages. 展开更多
关键词 Maximum profits from resources fish biomass age of icefish Antarctic fish krill.
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Energy and Autohydrolysis By-Products from Industrial Crops
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作者 F. Lopez M.J. Feria J.C. Garcia M.A.M. Zamudio A. Perez A. Rivera 《Journal of Energy and Power Engineering》 2011年第2期142-148,共7页
The world is experiencing a growing shortage of raw materials which is especially severe in the energy sector and being worsened by the unfavorable environmental impact of a consumerist cultttre revolving around the e... The world is experiencing a growing shortage of raw materials which is especially severe in the energy sector and being worsened by the unfavorable environmental impact of a consumerist cultttre revolving around the exploitation of non-renewable resources. In this work, the calorific value and chemical composition of liquors resulting from the autohydrolysis of six different lignocellulosic materials was determined (Eucalyptus globulus, Arundo donax, Leucaena diversifolia, Paulownia fortunei, Sunflower stalks and Chamaecytisus proliferus) and was assessed for the obtainment of energy, sugars and other chemical products by using of integral fractionation based on autohydrolysis. Autohydrolysis processes have been considered interesting in the case of timber species studied compared with herbaceous species with variations in the extraction of the xylan fraction at 180℃ between 19.68% for Eucalyptus globulus and 36.79% for Leucaena diversifolia and 200℃ between 57.86% for Paulawniafortunei and 79.13 % for Chamaecytisusproliferus. In general, all materials show a solid fraction "more energy" from the hydrolysis to 200℃ than 180℃ and raw materials. It is interesting as the potential economy valuation of the liquid fractions of the hydrolysis, the solid waste recovery present more energetic profitability. 展开更多
关键词 AUTOHYDROLYSIS BIOMASS BIOREFINERY ENERGY industrial crops.
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