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1.
矫晓阳 《海洋预报》2004,21(2):56-63
首次提出并探索了采用单一参数叶绿素a进行赤潮短期预报的原理和技术。该原理主要以叶绿素a大于某一基准值时连续2d是否呈指数增长来判定未来1~3d内是否会发生赤潮。对于任何海区,都仅基于叶绿素a基准值和增长速率下限两个常数即可进行预报操作。  相似文献   

2.
首次提出并探索了采用单一参数叶绿素a进行赤潮短期预报的原理和技术.该原理主要以叶绿素α大于某一基准值时连续2d是否呈指数增长来判定未来1~3 d内是否会发生赤潮.对于任何海区,都仅基于叶绿素α基准值和增长速率下限两个常数即可进行预报操作.  相似文献   

3.
刘珂  侯建伟 《海洋预报》1999,16(2):74-78
本文通过对青岛海区风浪资料进行处理分析,应用风浪经验预报公式进行检验,给出了适合该海区的预报公式,使用效果良好。  相似文献   

4.
潮流场永久预报方法及应用   总被引:3,自引:0,他引:3  
本方法的特点是以一个假想的引潮天体来代替月球和太阳的引潮作用.用该引潮天体星下点处的引潮力作为预报指标,对海区的整个潮流场进行计算与预报。在本方法中,把潮流场分为两种类型:把周日不等最弱的流场,称为Ⅰ型流场;把周日不等最强烈的流场,称为Ⅱ型流场。介于这两者之间的流场,则为过渡性的流场,流场的周期是与星下点处引潮力的周期相同。本方法已运用于渤海和北黄海.提供了该海区的表层流场永久预报图,并成功地进行过多次预报。  相似文献   

5.
在该海域潮流数值计算的基础上,用二维乎流—扩散模型对烟台北部近岸海域进行了COD(化学耗氧量)及油类污染的数值计算,并对1995年和2000年两个年代的水质状况进行了预测。给出了该海区未来10年内海水水质状况的发展趋势。  相似文献   

6.
用多层递阶周期分析作西沙海区热带气旋长期预报   总被引:2,自引:0,他引:2  
聂桂珍  任崇 《海洋预报》1997,14(2):53-57
本文分析了47年西沙海区热带气旋活动的概况,并针对该海区热带气旋预报的难度,运用文献[1]提出的多层递阶周期分析方法制作影响西沙海区热带气旋的长期预报取得了良好的效果  相似文献   

7.
人工神经网络技术在台风浪预报中的应用   总被引:4,自引:0,他引:4       下载免费PDF全文
利用人工神经网络中的BP算法,结合南海硇洲岛海区近30年的台风及台风浪资料,经预期因子的选择并作对比试验,建立了本海区较为理想的台风浪人工神经网络预报模型。结果表明:人工神经网络方法在台湾浪的预报上,有较好的拟合历史台风浪高的能力,利用该模型对台风浪高的预报也达到了一定的精度。为实际台风浪浪的预报增加了新方法、新思路。  相似文献   

8.
浙闽沿海和台湾海峡海域冬季大风风速计算方法探讨   总被引:4,自引:0,他引:4  
本文利用东海区海陆大风对比试验结果及26艘船只两个月的海上航测实况资料,通过对各种风速进行海陆比值分析、差值分析和测站间对比分析。论证了据陆上大风推算该海区大风风速计算式的可靠性,从而为实时、定量地预报海区大风提供了1种方法.  相似文献   

9.
该图集是受山东省科委的委托、由国家海洋局第一海洋研究所的科技人员采用了一种新型的潮流场预报方法编著的。图集分两个部分:一是以预报海区中的观测资料为依据绘制的潮流场永久预报图;二是根据引潮天体(月球、太阳合成体)星下点处引潮力的精确计算值编制(?)潮流场预报表。在潮流场永久预报图中又分Ⅰ型和Ⅱ型两种典型的  相似文献   

10.
燕松  邓冰  尹建平  范磊 《海洋预报》2007,24(4):49-54
利用统计预报中逐个引入因子法的原理和方法,选取了10年的气象资料,对浙江东部海区春季平流雾进行了分型研究,建立预报方程,确定预报临界值。通过对3年的气象资料进行试报,结果表明,预报准确率达到80%以上,基本上可以投入到正常的业务使用中。  相似文献   

11.
Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium ( 〈 0.4 μm) exis- ted in the low molecular mass fraction ( 〈 10 000 u), and the colloidal uranium-238 (10 000 u -0.4 μm) only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases ( 〉 0.4 μm), the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows: 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows : 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value (1.0). The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the partic  相似文献   

12.
夏季珠江口沉积物中营养盐剖面分布和界面交换通量   总被引:21,自引:4,他引:21  
通过对夏季珠江口区域沉积物间隙水营养盐剖面分析,调查了营养盐含量分布和特征,探讨了有机物的降解特性、营养盐的底部通量估算和作用.结果表明,珠江口沉积物间隙水中营养盐以高含量铵盐为主要的存在形式,沉积物中有机物的降解反应主要在厌氧状态下进行,底部水体铵盐的增加来源于底部沉积物有机质的降解释放,而且对水体的营养盐循环有较大的贡献.  相似文献   

13.
In China submarine geosciences represents a newly established discipline of oceanography, focusing on the oceanic lithosphere, and its interface with the hydrosphere and biosphere. Recently, supported by the National High Technology Research and Development Program and other high-tech development projects, significant progress has been made in the development of advanced technologies and equipment. This en- ables the scientists in China to carry out explorations of the international seabed area in the Pacific Ocean and on the Southwest Indian Ridge. In addition, they have been active in the research activities associated the mid-ocean ridges and western Pacific marginal seas. It is anticipated that this research field will continue to be highly fruitful in the near future.  相似文献   

14.
湄洲湾夏季的初级生产力   总被引:2,自引:3,他引:2  
王宪  李文权 《台湾海峡》1994,13(1):8-13
湄洲湾1992年夏季的叶绿素a,三磷酸腺苷,碳比积累速率,初级生产力的变化范围和均值分别为0.45-4.72,1.49mg/m^3;0.12-1.07,0.31μg/dm^3;0.06-0.58,0.34d^-1;0.07-0.34,0.21m/(m^2.d)。叶绿素a与三磷酸腺苷之间。初级生产力与碳比积累速率之间均呈正相关关系。叶绿素a三磷本能腺苷的比值为4.8,湄洲湾夏季浮游植物的生长受氮不足  相似文献   

15.
Marine environment protection in Europe faces a number of challenges. One is the coordination of relevant sectoral policies — such as agricultural and fisheries policies — with regard to marine protection objectives. The question in the following is on how marine protection issues can be more closely integrated in sectoral policies under the conditions prevailing at present. In particular the strength and weaknesses of the Marine Strategy Framework Directive (MSFD) as the key instrument for marine environment protection in Europe are analyzed in this context. In particular, the MSFD does not adequately address all sectors and policies which are relevant to marine environment protection. One possible means of giving the MSFD greater influences on other policies of relevance to marine waters is to integrate the objectives established under the MSFD in the European maritime policy. The aim should be to require the further development of sectoral policies to take unrestricted account of the objectives of the MSFD implementation process. But also other instruments of marine policy such as maritime spatial planning and marine protected areas are crucial to advance the protection of European seas.  相似文献   

16.
17.
Much of the recent Canadian activity in marine technology has focused on development of capabilities in Arctic waters, and on the update and replacement of naval vessels. This paper describes some of the significant projects and programs now under way, and suggests future research and development requirements.  相似文献   

18.
对一氧化氮在浮游植物中的研究进展进行了归纳,总结了一氧化氮对浮游植物生长的影响,探讨了浮游植物中一氧化氮的产生机制,并对今后的研究重点提出展望。  相似文献   

19.
In order to investigate factors controlling nutrient cycling in the shallow and turbid coastal ecosystem of Galveston Bay, data from: (1) the Texas Water Commission (TWC) database 1980–1989, and (2) salinity transects in 1989 and 1993 are presented and analyzed. Statistical regression and time-series analysis were carried out on data acquired by TWC between 1980 and 1989, in an attempt to establish seasonally of nutrient and chlorophyll-a (chl.-a.) concentrations in the bay and to determine factors which regulate these concentrations.A strong seasonality was found for phosphorus and chl.-a. in the upper and mid-bay stations. A recurring maximum for phosphate occurred in September and a chl.-a. maximum occurred regularly in March–April. It is hypothesized that benthic regeneration of phosphorus at the end of summer is responsible for the phosphate maximum. The inverse correlation of the partition coefficient (Kd) for phosphate with the concentration of suspended particulate matter (SPM), coupled to a strong enrichment of phosphate in suspended particles at low SPM concentrations, indicates additional control by geochemical and physical processes such as particle sorting and/or particle-colloid interactions. Nitrate is inversely correlated with salinity at the upper and mid-bay stations, indicating the Trinity River is a major source.Nutrient concentrations in the lower bay (East and West Bay stations) are considerably lower and less predictable, as they are not correlated with salinity or temperature. Data from the 1989 and 1993 transects confirm the yearly maximum in phosphate concentration in late summer months, with peak concentrations in the upper Trinity Bay. It is concluded that despite possible phosphate buffering by physical and geochemical mechanisms, relatively large concentration maxima recur regularly every year during the summer, possibly caused by a benthic source of phosphate.  相似文献   

20.
中国科学院海洋研究所建所70年来,在海洋贝类分类学研究领域取得了长足发展与进步,做出一系列开创性研究成果。本文综述了建所以来我所海洋腹足类分类学研究方面的主要进展,概述了取得的主要科研成果,分析了现代腹足类分类学研究的发展趋势以及面临的挑战,并对今后的发展提出了相应对策和建议。  相似文献   

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