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81.
In order to analyze the condition of special landform and regularity of special hydrological movement inkarst area, the method of Geomorphologic Instantaneous Unit Hydrograph (GIUH) has been used to divide the river net-works into three grades in the research area and the karst hydrologic processes were simulated with Nash instantaneous u-nit hydrograph(NIUH). The combination of the GIUH and NIUH fully considers the moving path of water particles indrainage and the regional composition of runoff at the end of the drainage, resulting in a rational combination of probabili-ty of GIUH and NIUH and geomorphologic parameters which could reflect the complexity of the landform structure ofkarst drainage. The results showed that the combined method of GIUH and NIUH has clear physical concept and accept-able precision, which can be widely applied on hydrological studies of karst area.  相似文献   
82.
Carrada  G.C.  Hopkins  T.S.  Bonaduce  G.  Ianora  A.  Marino  D.  Modigh  M.  Ribera  D'Alcalà M. Scotto  di Carlo B. 《Marine Ecology》1980,1(2):105-120
Abstract. Recent observations of physico-chemical and biological parameters in the Gulf of Naples are summarized. The water masses present within the Gulf during the various periods of the year are described. The temporal and spatial distribution of surface nutrients (N-NO3, P-PO4, Si-SiO4) and chlorophyll a are reported and the areas exposed to local eutrophication are identified. Biweekly sampling at a reference station has permitted us also to identify both phytoplankton and zooplankton seasonal cycles. The morphology of the basin and the uneven land runoff distribution are interpreted as causal to the variability of chemico-physical parameters and of the associated biological communities, giving rise to two subsystems (coastal and "open water") within the Gulf.  相似文献   
83.
Abstract. Nitzschia sicula (C astr .) H ust ., a planktonic pennate diatom, dominated the microphytoplankton (104-5 times 104 cells. 1-1) in the central, oligotrophic Southern Adriatic Pit waters (20-50m layer) in May 1990. Nauplii dominated the microzooplankton (3 indiv. 1-1in the 0-50m layer, 130 μm mean body length) and produced a considerable amount of faecal (mini)pellets (1900. 1-1 at 50m, mean diameter 47μm), which were compactly filled with N. sicula frustules. The subsurface accumulation of diatoms and nauplii was probably the result of both productive activity under specific hydrographic conditions and the convergence in a relatively strong southern Adriatic cyclonic gyre; the advective transport of populations along the shear zone, at the boundary between water masses of different thermo-haline characteristics may also have played a role. The amount of minipellets was high if compared with the data available from other seas. This was probably due to high production of minipellets, their slow sinking rate, and/or an absence of manipulation of the faecal material by zooplankton.  相似文献   
84.
In February, May and August 1994, four stations in the North Sea (viz. at the Broad Fourteens, Frisian Front, German Bight and Skagerrak) were visited to sample near-bottom particulate organic matter. Samples, taken by means of a pump, a sediment trap and a sediment recorder, were analysed on organic carbon, total nitrogen, phytopigments and fatty acids. These molecular markers were used to describe the nature and quality of the organic particles in the near-bottom water. Principal component analysis showed chlorophyll a, phaeopigments and fatty acids to be useful markers for the quality of organic matter and yield complementary information.The quality of the near-bottom particles appeared to be related to the local hydrography and depositional circumstances. The Broad Fourteens station, a non-depositional sandy site along the Dutch coast, showed organic particles to be relatively fresh, little influenced by resuspended sedimentary material. Near-bottom organic particles on this site contained relatively high shares of chlorophyll a and polyunsaturated fatty acids, characteristic of algal matter. On the other hand the particulate organic material on the two depositional locations, the Frisian Front and the German Bight stations, was influenced by resuspension of sedimentary organic particles poor in pigments and fatty acids. Amounts of carbon trapped in the near-bottom environment at the Skagerrak station were lower than expected from the literature.  相似文献   
85.
秦山核电站邻近水域的基本水文特征   总被引:2,自引:0,他引:2  
文章根据1989年4、7、10月和1990年1月在秦山核电站邻近水域获得的水文观测资料,对该区域中海水温度、盐度、浊度、水色和透明度以及潮汐、潮流等要素的分布和变化特征进行了较为详尽的分析,为进一步了解该水域的基本水文状况和海水运动的基本规律提供了重要依据。  相似文献   
86.
1987年9月,我们进行了一次详细的调查,确定了东库克海峡(Cook Stait)中腔吻鳕的卵及稚鱼分布与水文状况的关系。由于地方性风的原因,当地的水文结构非常复杂。南塔拉纳基湾(Taranaki Bight)水占据了库克海峡北部和中部的大部分水域。克劳迪湾(Cloudy Bay)沿岸水被河水冲淡,并由于库克海峡峡谷上升流进入克利福德湾(Clifford Bay)和开普.坎贝尔(Cape Campbell)南部沿岸,使克劳迪湾的沿岸水向近岸呈羽状伸展。东开普流水体出现在库克海峡峡谷水深200m附近和陆架外缘。开普.帕利瑟(Cape Palliser)南部的深层混合说明,该地区有一股反气旋涡旋。叶绿素α浓度与混合层深度有关,它在垂直分层的表面水体中最高。腔吻鳕卵在库克海峡峡谷内最多,该地区是这种鱼类著名的产卵场。小的腔吻鳕稚鱼(2.0~3.9mm)数在卵高密度集区和开普。坎贝尔附近最多,而较大的稚鱼(>10mm)在近岸区最多。根据刚孵化出来的稚鱼的分布情况来看,腔吻鳕卵随着当地的上升流进入开普。坎贝尔的近岸地区。  相似文献   
87.
介绍了海军大连舰艇学院海洋测绘系实习队参加第18届国际海道测量大会的情况。总结了实习、参会的具体做法及收获和体会,在此基础上,对如何完善海洋测绘系海道测量本科学员毕业综合实习提出了思考和建议,也对海洋测绘系的学科发展具有启示意义。  相似文献   
88.
介绍了第18届国际海道测量大会概况,通过实地见闻,简要总结和展望了国际海道测量发展的新趋势。旨在对我国海洋测绘事业的发展提供借鉴和参考。  相似文献   
89.
海面有效波高(H1/3)是表征海浪的重要参数,随着卫星遥感技术的发展,雷达高度计已成为获取海面有效波高的重要手段,但也只能对卫星星下点轨迹处进行有效观测,远无法满足大范围应用的需求.本研究结合2013年10月HY-2雷达高度计观测的海面有效波高和微波散射计观测的海面风场资料,分别对高、低风速下风浪数据进行拟合,建立了适用于0~40 m/s风速范围内的南海海域风浪关系模型,经模型比对和结果验证,结果表明,基于HY-2卫星数据分析建立的南海海域风浪关系模型是可信的,特别是低风速的风浪模型与实测数据建立的风浪模型具有很好的一致性;根据建立的风浪关系模型,从卫星散射计大面观测的海面风场出发,能推算出风浪条件下海面有效波高的大面信息,数据覆盖远高于卫星高度计的星下点观测,能为分析和预报海浪、风暴潮灾害提供大范围的海面有效波高信息.  相似文献   
90.
Transport processes were studied in a gully between a salt marsh and an estuary. After storm tides, ebb currents in the gully reached high values. It is concluded that particulate matter (both organic and inorganic) are imported into the marsh. Coarse organic debris is exported during storm tides, but this amount is low when compared with the primary production on the marsh. Exports are shown for dissolved organic carbon, ammonia, phosphate and silica, while nitrate and possibly nitrite are imported. Organic matter derived from in situ production and net import is buried and partly mineralized in the marsh.  相似文献   
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