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51.
In recent years, the red tide erupted frequently, and caused a great economic loss. At present, most literatures emphasize the academic research on the growth mechanism of red tide alga. In order to find out the characters of red tide in detail and improve the precision of forecast, this paper gives some new approaches to dealing with the red tide. By the extreme values, we deal with the red tide frequency analysis and get the estimation of T-times red tide level U (T) , which is the level once the consistence of red tide alga exceeds on the average in a period of T times. 相似文献
52.
REEdistributioninwater-sedimentinterfacesystematdeepoceanfloor¥ZhangLijie;LiuJihuaandYaoDe(ReceivedFebruary1,1994;acceptedMay... 相似文献
53.
近海水域有机物污染,引起海水富营养化,是形成赤潮的主要原因。赤潮不仅给渔业生产、海水养殖业带来重大损失,而且破坏了海洋环境,危及人民的健康。近年来,我国沿海赤潮时有发生,应加强对有发生赤潮潜在危险海区的经常性观测和监测;切实控制沿海工业和生活污水的任意排放;科学、合理地开发利用海洋资源;推广科学养殖技术,防止海水养殖自身污染;大力开展有关赤潮科学的研究,特别是赤潮的防治方法和技术研究,避免或减少赤潮造成的危害 相似文献
54.
中国沿岸现代海平面变化及未来趋势分析 总被引:2,自引:0,他引:2
本文用线性回归分析方法,分1985年以前和1992年以前两个时段,对我国沿岸25个验潮站近百年来的海平面资料进行了系统分析,计算了两个时段相对海平面变化的年速率和平均海面高度,论述了海平面变化的主要控制因素,并对未来海平面变化趋势进行了预测。计算结果表明,近百年来我国沿岸相对海平面在总体上不但持续上升,而且近年来上升速率普遍加快;根据海平面变化的主要控制因素变化趋向,预计到下世纪中叶前后,全球性海平面大幅度上升的可能性不大,我国沿岸区域性海乎面平均上升幅度不超过15cm,不同岸段因地壳升降差异性大而有较大差别。 相似文献
55.
56.
青岛地区的台风暴潮与潮灾 总被引:3,自引:0,他引:3
本文分析了青岛沿海地区的台风暴潮灾害状况,给出了潮位与海浪的联合作用对灾的影响关系式,提出了今后风暴潮预报的思路。 相似文献
57.
Biochemical mechanism of forming the red tide is discussed in this paper.The existence of a large number of nitrates and phosphates in the eutrophic water is the prerequisite of explosive increase of algae and the forming of red tide.Reduction of eutrophication is an important approach to preventing the red tide.The method of deep treatment of the waste water and its denitrification and dephosphorization are introduced,and a new opinion on the red tide formation and fundamental prevention is put forward. 相似文献
58.
59.
A study on the curves of the exchange ratio E(%)-pH on the liquid-solid interface of the systems Zn(II) with clay minerals (Kaolinite , illite and montmorillonite), Zn(II) with hydrous ferric oxides (amorphous ferric oxide, goethite and hematite). Zn(II) with hydrous manganese oxide (y-MnOOH, manganite and 5-MnO2) etc . in seawater resulted in the discovery of new plateau type exchange ratio ?%)-pH curves not yet reported in literature. The two factors that decide the growth , decline and the change of the " plateau type " curve are : (1) the inherent characteristics of systems , which can be explained by the exchange constants i(i=1 ,2 , 3 . etc .) of interfacial stepwise ion / coordination particle exchange between liquid and solid ; and (2)The theory of interfacial stepwise ion/coordination(the amount of solid exchange reagent)particle exchange in seawater was applied to explain the experimental results of the above study and a general formula was derived for the plateau type exchange ratio E(%)-pH c 相似文献
60.
Ocean tide loading (OTL) displacements from global and local grids: comparisons to GPS estimates over the shelf of Brittany, France 总被引:1,自引:0,他引:1
Stavros A. Melachroinos R. Biancale M. Llubes F. Perosanz F. Lyard M. Vergnolle M. -N. Bouin F. Masson J. Nicolas L. Morel S. Durand 《Journal of Geodesy》2008,82(6):357-371
In this paper we examine OTL displacements detected by GPS stations of a dedicated campaign and validate ocean tide models.
Our area of study is the continental shelf of Brittany and Cotentin in France. Brittany is one of the few places in the world
where tides provoke loading displacements of ∼10–12 cm vertically and a few cm horizontally. Ocean tide models suffer from
important discrepancies in this region. Seven global and regional ocean tide models were tested: FES2004 corrected for K2,
TPXO.7.0, TPXO.6.2, GOT00.2, CSR4.0, NAO.99b and the most recent regional grids of the North East Atlantic (NEA2004). These
gridded amplitudes and phases of ocean tides were convolved in order to get the predicted OTL displacements using two different
algorithms. Data over a period of 3.5 months of 8 GPS campaign stations located on the north coast of Brittany are used, in
order to evaluate the geographical distribution of the OTL effect. We have modified and implemented new algorithms in our
GPS software, GINS 7.1. GPS OTL constituents are estimated based on 1-day batch solutions. We compare the observed GPS OTL
constituents of M2, S2, N2 and K1 waves with the selected ocean tide models on global and regional grids. Large phase-lag and amplitude discrepancies over
20° and 1.5 cm in the vertical direction in the semi-diurnal band of M2 between predictions and GPS/models are detected in the Bay of Mont St-Michel. From a least squares spectral analysis of the
GPS time-series, significant harmonic peaks in the integer multiples of the orbital periods of the GPS satellites are observed,
indicating the existence of multipath effects in the GPS OTL constituents. The GPS OTL observations agree best with FES2004,
NEA2004, GOT00.2 and CSR4.0 tide models. 相似文献