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991.
叶雯 《海洋信息》2002,(3):9-11
阳江市位于广东省西南部沿海,是一个滨海城市,海洋是阳江社会经济发展的生命线。阳江的优势在海,发展潜力也在海。近十几年来,阳江 市在开发利用海洋资源方面取得了显著成绩,然而也存在一些不足之处。如何将阳江的海洋资源优势转化为经济优势、科学合理开发利用海洋资源、实现可持续发展,是阳江市建设“海洋强市”、发展海洋经济的关键。  相似文献   
992.
INTRODUcrIONAs a quality seaha, lobster has a greater market demand or higher demand than supply. Inrecent years the natural resource of lobster is decreasing day by day due to overfishing oPera-tions. Conequently, an attention has been increasingly drawn to the development of artificialbreeding in lObster and seedstock preduction. From the l970s to the l980s the culture of lobsterlarva started but with very slow pngress. Inoue et al. (l978), Yamakawa et al. (1989), Kitta-ka and Kimura(l…  相似文献   
993.
叶建平 《台湾海峡》1992,11(3):273-280
本文系根据1980~1989年福建省在台湾海峡生产的48组具有代表性的标本船之技术经济资料,以柯布·道格拉斯生产函数和经济指标评析其生产状况及技术经济效果。结果表明,近年来,福建省灯光围网渔船的宏观技术水平已明显提高;然而因其捕捞努力量大幅度增加,单位捕捞努力量渔获量曲线呈抛物线状,其长期趋势为CPUE=-0.311+0.9032f-0.06397f~2;预测投资在功率范围为147~294kW的灯光圈网渔船在台湾海峡生产可望受益。  相似文献   
994.
Some observational results of sea storm current   总被引:3,自引:0,他引:3  
INTRODUCTIONDr. Hollister, a marine geologist of the Woods Hole Oceanographic Institution, firstpointed out that there was ocean storm current in the ocean. He found out the wavy texture inthe seabed core samples, and suggested that this wavy texture was caused by the high speedsea current in remote antiquity. He then suggested a bold hypothesis that there existed a benthic storm current near the ocean bottom, and presented this hypothesis at the IUGG confer-ence held at San Francisco…  相似文献   
995.
The ages of coral reef samples from several shallow drill holes in the South China Sea are determined by ESR and U-series (230Th/234U) methods. The experimental results show ideal agreement between ESR and U-series ages and that the coral reefs were formed in the early Holocene. In the determination of natural total dose of coral reef by use of the additive dose method good results can be obtained by exponential fitting, no matter how the effect of dose saturation is. It was found that the ratio of the natural ESR signal intensity ( I0) to the ESR signal intensity at dose saturation ( Imax) of sample can reflect the significance of a irradiation efficiency-k value. Using the k value of sample determined by the formula given in this paper, the precision of ESR dating of marine carbonates can be improved.  相似文献   
996.
997.
Graphical methods have been widely used for visualization, classification, and interpretation of aqueous geochemical data to obtain a better understanding of surface and subsurface hydrologic systems. This method note presents WQChartPy, an open-source Python package developed to plot a total of 12 diagrams for analysis of aqueous geochemical data. WQChartPy can handle various data formats including Microsoft Excel, comma-separated values (CSV), and general delimited text. The 12 diagrams include eight traditional diagrams (trilinear Piper, Durov, Stiff, Chernoff face, Schoeller, Gibbs, Chadha, and Gaillardet) and four recently proposed diagrams (rectangle Piper, color-coded Piper, contour-filled Piper, and HFE-D) that have not been implemented in existing graphing software. The diagrams generated by WQChartPy can be saved as portable network graphics (PNG), scalable vector graphics (SVG), or portable document format (PDF) files for scientific publications. Jupyter and Google Colab notebooks are available online to illustrate how to use WQChartPy with example datasets. The geochemical diagrams can be generated with several lines of Python codes. Source codes of WQChartPy are publicly available at GitHub ( https://github.com/jyangfsu/WQChartPy ) and PyPI ( https://pypi.org/project/wqchartpy/ ).  相似文献   
998.
999.
The seasonal variability of leaf litter removal by crabs was observed from May 2006 to April 2007 in a Kandelia candel mangrove forest in Jiulongjiang Estuary, China. Daily average quantities of leaf fall ranged 0.85–3.86 gDW m−2 d−1, with high values in May, August, October and November. The whole-year's leaf fall was 6.48 t ha−1 yr−1 (1.81 gDW m−2 d−1). The standing stock of leaf litter on the forest floor was 7.78 gDW m−2 averaged from the whole year's data, with the lowest value in December (1.23 gDW m−2) and the highest in April (16.18 gDW m−2). Annually averaged removal (consumption on mangrove floor + burial in burrows) rate of leaf litter by crabs was 0.59 gDW m−2 d−1. High seasonal variability was observed in the removal rates of leaf litter by crabs. Removal rates in the winter months (December, January and February) were 0.07–0.09 gDW m−2 d−1, much lower than those in other months with values of 0.59–1.18 gDW m−2 d−1. Annually averaged percentage of leaf fall removed by crabs was 33%, with the highest values in September (reached 76%) and the lowest values in winter months. Of leaf litter removed by crabs, a large proportion was buried by crabs, and only 12% was consumed by crabs on the forest floor. Leaf litter removal rate, consumption rate on the forest floor, percentages of leaf fall and standing stock removed on the forest floor were significantly positively correlated with air temperature, indicating that leaf removal ability by crabs was higher in warm months than in cold months.  相似文献   
1000.
基于空域的帧内预测是H.264采用的一项重要技术,对编码性能的提高具有重要作用。但是由于支持的帧内预测模式较多,使用率失真优化模型计算的编码复杂度很高。利用像素边缘方向信息,相邻块预测模式间的相关性提出了一种帧内模式选择快速算法,可以预先排除约60%的预测模式,从而减小对率失真优化模型的调用。实验结果表明,算法在基本保持H.264原算法性能的同时,编码时间减少70%以上。  相似文献   
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