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71.
象山港、三门湾软相潮间带底栖动物数量的水平分布与港湾的屏蔽性程度有一定的关系,生物量是三门湾(180.95g/m2)高于象山港(94.47g/m2),生物密度是象山港(816个/m2)高于三门湾(347个/m2)。决定所面生物数量变化的主要底栖动物种类数随着港湾屏蔽性程度的提高而相应地减少。生物数量的垂直分布主要受潮汐作用的影响,以中潮区为最高。生物量以6月份最大,密度是4月份最大。 相似文献
72.
海底沉积物孔隙度与声速的关系 总被引:15,自引:10,他引:15
给出大陆架海底沉积层中声速(压缩波)Vp依赖于沉积物孔隙度n的一个新的经验公式,该公式当n=100时,Vp=V0,V0为海底水声速.公式的计算值与我国周边大陆架测量值吻合较好,并将其结果与国内外成果作了对比讨论. 相似文献
73.
A new methodology to classify European North-East Atlantic transitional waters into ecological types has been developed based on the most important hydrological and morphological features that are likely to determine the ecology of aquatic systems in transitional waters. Hydrological indicators help identifying if a transitional water area is dominated by fresh or sea water and/or by intertidal or subtidal areas, while morphological indicators allow an estimation of the complexity of the transitional water and the diversity of the habitats involved. Twelve transitional waters of the southern Bay of Biscay were classified using this methodology and the five hydro-morphological types obtained were validated with benthic macro-invertebrate data. Transitional waters with a complex morphology showed the highest values of species diversity, while those with a smaller tidal influence showed lower species diversity. The ‘Scrobicularia’ and ‘Abra’ assemblages, previously identified in the study area, were found to be related to different types of transitional waters. The ‘Abra’ assemblage only appeared in estuaries with a complex morphology and dominated by tidal influences, while the ‘Scrobicularia’ assemblage was detected in all the transitional waters except for a single coastal lagoon. This classification of transitional waters may therefore be useful to establish the biological reference conditions needed for European Directives. 相似文献
74.
利用1951~2003年HadISST资料集的表层海水温度(SST)资料,讨论了印度洋-西太平洋暖池(IPWP)海域,尤其是印度尼西亚贯穿流(ITF)及其周边海域SST的季节及年际变化的时空特征.研究结果表明,整个研究海域SST的年际变化均与ENSO相关,但印度洋与南海的响应特征与西太平洋的相反且不同步.前者海温变化滞后Nio3指数3~6个月,而热带太平洋西边界和ITF流经海域海温则超前1~3个月.沿ITF及其东印度洋出口,SST的年际变化规律不同于热带印度洋而与太平洋的相似,分析表明其在较大程度上受到ITF海洋桥的影响.在季节尺度上,印度洋和太平洋赤道海域SST的波动规律也有明显不同.以巽他岛弧(苏门答腊、爪哇和小巽他群岛)为界,从赤道西太平洋向西沿ITF流径,太平洋一侧SST的季节变化以0.5a周期的波动占主导,印度洋一侧则以1a周期占主导. 相似文献
75.
Microwave remote sensing has become the primary means for sea-ice research, and has been supported by a great deal of field experiments and theoretical studies regarding sea-ice microwave scattering. However, these studies have been barely carried in the Bohai Sea. The sea-ice microwave scattering mechanism was first developed for the thin sea ice with slight roughness in the Bohai Sea in the winter of 2012, and included the backscattering coefficients which were measured on the different conditions of three bands(L, C and X), two polarizations(HH and VV), and incident angles of 20° to 60°, using a ground-based scatterometer and the synchronous physical parameters of the sea-ice temperature, density, thickness, salinity, and so on. The theoretical model of the sea-ice electromagnetic scattering is obtained based on these physical parameters. The research regarding the sea-ice microwave scattering mechanism is carried out through two means, which includes the comparison between the field microwave scattering data and the simulation results of the theoretical model, as well as the feature analysis of the four components of the sea-ice electromagnetic scattering. It is revealed that the sea-ice microwave scattering data and the theoretical simulation results vary in the same trend with the incident angles. Also, there is a visible variant in the sensitivity of every component to the different bands.For example, the C and X bands are sensitive to the top surface, the X band is sensitive to the scatterers, and the L and C bands are sensitive to the bottom surface, and so on. It is suggested that the features of the sea-ice surfaces and scatterers can be retrieved by the further research in the future. This experiment can provide an experimental and theoretical foundation for research regarding the sea-ice microwave scattering characteristics in the Bohai Sea. 相似文献
76.
利用1995~2013年间NCEP风场资料,分析研究了台湾西南部海域风应力旋度偶极子的季节和年际变化特征,及其受ENSO事件的影响,结果表明:台湾西南部海域风应力旋度偶极子的分布存在明显季节变化,其分布期主要集中于每年10月至次年4月,夏季台湾海峡不存在风应力旋度偶极子的分布;风应力旋度偶极子的强度异常要滞后ENSO 1个月,当厄尔尼诺事件发生时,风应力旋度偶极子的分布强度较正常年份要弱,而当拉尼娜事件发生时,风应力旋度偶极子的分布强度较正常年份要强;风应力旋度偶极子的分布还存在准16.0个月和准45.3个月的显著年际变化周期,其变化同ENSO循环密切相关. 相似文献
77.
北部湾盆地迈陈凹陷中南部Y井井壁取心分析、岩屑样品的薄片鉴定结果及地球物理测井综合评价表明,其钻遇的不同层位层段的储层类型主要以含泥质较高的砂岩、粉砂岩及泥质粉砂岩为主,少量砾岩,多属于近—中物源快速沉积充填、储集物性偏差的储集层类型,且成岩程度偏低(处在早成岩A或B期或中成岩A期),总体上属于岩性较细、泥质含量偏高、孔渗参数偏低的中孔中渗和低孔低渗及低孔特低渗型砂岩储层类型。其中,钻遇的渐新统涠洲组砂岩储层总体上偏细且泥质含量较高,砂岩有效孔隙度和渗透率偏低,属于储集物性较差储层;始新统流沙港组二段砂岩属于差—较好储层,储层孔隙类型以粒间孔为主,其次为粒间溶孔,还发育有少量或微量长石溶孔和粒内溶孔,具有一定的孔渗性;古新统长流组砂岩孔隙类型以粒间孔、粒间溶孔为主,发育少量长石溶孔及粒内溶孔,储层致密储集物性偏差。总之,本区储层发育主要受控于碎屑物物源供给远近与沉积相及成岩作用,但总体上储层成岩程度较低,加之溶蚀作用及胶结作用普遍,故严重影响了储层储集物性。 相似文献
78.
ABSTRACT Marine manganese nodules and crusts, when processed, yield tailings which may be utilized for environmental and economic benefit. The key to the reasonable and effective utilization of these tailings lies in making a systematic appraisal of their composition and properties. This article gives an introduction to the investigation of manganese tailings properties. The tailings have a high iron and/or manganese content, high surface area, high porosity, and fine grain size. Some tailings have a high rare earth element content which is valuable. They may also have high SO3, arsenic, and uranium contents which are harmful. Depending on the process used to produce the tailings, there will likely be some differences in chemical composition, mineral assemblages, surface area and adsorption capability, pore diameter and volume, density and pH. In assigning potentially beneficial applications for these tailings, these differences should be taken into account to optimize utilization. 相似文献
79.
Susmita Sharma 《Marine Georesources & Geotechnology》2013,31(5):447-465
Sediments are the particulate matter that are transported by the flow of water and eventually get deposited at the bottom of water bodies, such as oceans, rivers, lagoons, and so forth. The deposition of these materials due to continued intervention of natural as well as anthropogenic activities is a serious concern as the storage capacity (or health) of the system is reduced or otherwise affected. Keeping in view the emerging challenges associated with proper disposal and subsequent utilization of sediments, as a manmade resource, their extraction from such locations becomes necessary. Hence, it is essential to characterize the sediments in order to devise strategies to exploit them as a manmade resource in the best possible manner. With this in view, this article highlights the importance of different attributes and aspects of the sediments (viz., physical, chemical, morphological, geotechnical, toxicological, and microbial characteristics) deposited in the water bodies that will help in assessing their potential as a substitute material to natural resources. 相似文献
80.