热液喷口探测化学传感器的研制及应用*

海底热液喷口周围的水体具有显著的浊度和化学组分异常, 是寻找热液喷口的重要标志。文章提出了一种海底热液喷口的探测技术方法, 设计了低功耗化学传感器。该化学传感器可搭载在相关平台, 实时探测水体的Eh、H₂S、pH及CO₃^2-等电位值, 结合浊度异常, 可以推断热液喷口的位置。在西南印度洋中脊海试结果表明, 该化学传感器可有效探测由热液活动产生的水体异常, 是一种探测海底热液喷口的有效技术。     

利用WAVEWATCH和SWAN嵌套计算珠江口附近海域的风浪场*

基于CCMP(Cross Calibrated Multi-platform)卫星遥感海面风场数据,通过将WAVEWATCH和SWAN (Simulating WAves Nearshore)模型嵌套的方法,数值模拟了珠江口附近海域的风浪场。将总计10个月的数值模拟的有效波高、波周期和波向分别与相应的观测值进行了定量比较。结果说明,有效波高的平均绝对误差为15.4cm,分散系数SI为0.240,相关系数为0.925;波周期的平均绝对误差为1.9s,分散系数SI为0.433,相关系数为0.636;波向的平均绝对误差为23.9°。计算的波高和波向与观测结果的变化趋势相吻合。由于第三代海浪模式本身的缺陷,导致所计算的波周期偏小。总体说来,本文所采用的数值模式能较好地模拟珠江口附近海域的风浪场。另外,还设计了6个算例以探讨采用不同的计算方法和风场对计算结果精度的影响。结果表明使用本文的数值方法和高精度的CCMP风场确实可以提高计算结果的精度。     

对近183年我国南海冬季风变率的探讨： 来自珊瑚氧同位素的证据*

以西沙群岛现代澄黄滨珊瑚的冬季氧同位素记录为代用指标,重建了1818—2000年的南海冬季风风速。重建序列显示1818—1954年冬季风速以每年0.009m·s^-1的速率下降,而1955—2000年下降速率明显增强为每年0.021m·s^-1,46年间风速下降达20%。整个183年中冬季风速变化具有两个完整的强—弱波动特征,其中1830s和1940s为过去近两个世纪当中冬季风速最强和最弱的时期。20世纪的冬季风速变化与南海海表温度和中国陆地气温极为相似,相位相反,并揭示了1940s和1980s年代两个特征暖期。通过对冬季风速异常和ENSO暖、冷事件的统计分析,发现大多数ENSO事件发生时与冬季风减弱相对应。     

Spatial distribution pattern of seafloor hydrothermal vents to the southeastern Kueishan Tao offshore Taiwan Island

Investigations of the diffusion activities both within and outside the seafloor hydrothermal vents, as well as related mineral genesis, have been one of the key focuses of ocean biogeochemistry studies. Many hydrothermal vents are distributed close to the southern Okinawa Trough on the less-than-30-m deep shallow seafloor off Kueishan Tao, northeast of Taiwan Island. Investigations of temperature, pH and Eh at four depths of hydrothermal plume were carried out near Kueishan Tao at the white(24.83°N, 121.96°E) and yellow(24.83°N, 121.96°E) vents. An 87 h of temperature time series observation-undertaken near the white vent showed that tide is the main factor affecting the background environment. Based on the observed data, 3-dimensional sliced diffusion fields were obtained and analyzed. It was concluded that the plume diffused mainly from north to south due to ebb tide. The yellow vent's plume could effect as far as the white vent surface. From the temperature diffusion field, the vortices of the plume were observed. The Eh negative abnormality was a better indicator to search for hydrothermal plumes and locate hydrothermal vents than high temperature and low pH abnormalities.     

Investigation into extremely acidic hydrothermal fluids off Kueishan Tao, Taiwan, China

Kueishan Tao (24°51′N, 121°55′E) is located at a tectonic junction of the fault system extension of Taiwan and the southern rifting end of the Okinawa Trough. A cluster of over 30 vents, at a water depth of about 10-20 m off the eastern tip of the tao emits hy-drothermal fluids and volcanic gases such as H2S. A sulfur chimney or mound, formed by condensation of the sulfur contained in the hydrothermal fluid, can usually be seen around the     

Behaviors of 210Pb and 210Po around hydrothermal vents in the Okinawa Trough

Vertical profiles for the uranium-series radioisotopes 210Pb and 210Po were obtained at thetwo hydrothermal vent sites, the Iheya Ridge and the Minami-Ensei Knoll, in the Mid-Okinawa Trough in 1993 and 1994, respectively. In 1995, both radioisotopes were measured at the Minami-Ensei Knoll a-gain. At the Iheya Ridge, where the hydrothermal activity is not active as reflected by the CH_4, and 222Rn data, both the total 210Pb and 210Po activities show deficiency relative to their parents, and the mean residence time of 210Pb and 210Po is approximately equal to 20 and 2-5 a, respectively. At the Minami-Ensei Knoll, which is characterized by black smokers, the total 210Pb(0.167 × 10~(-3)-2.5 × 10~(-3)_ Bq/kg) around the plumes is deficient relative to 226Ra but the total 210Po activities (1.83 × 10 ~(-3) - 2.83 × 10~(-3) Bq/kg) are in excess relative to 210Pb. The 210Po activities are higher than those in the East China Sea and the Okinawa Trough and excess 210Po has been found. The 210Pb/226Ra and 210Po/     

Microbial community structure and diversity in deep-sea hydrothermal vent sediments along the Eastern Lau Spreading Centre

The aim of this study is to investigate microbial structures and diversities in five active hydrothermal fields’ sediments along the Eastern Lau Spreading Centre (ELSC) in the Lau Basin (southwest Pacific). Microbial communities were surveyed by denatured gradient gel electrophoresis (DGGE) and clone library analysis of 16S rRNA genes. The differences in microbial community structures among sediment samples from the five deep-sea hydrothermal sites were revealed by DGGE profiles. Cluster analysis of DGGE profiles separated the five hydrothermal samples into two groups. Four different 16S rRNA gene clone libraries, representing two selected hydrothermal samples (19-4TVG8 and 19-4TVG11), were constructed. Twenty-three and 32 phylotypes were identified from 166 and 160 bacterial clones respectively, including Proteobacteria, Bacteroidetes, Firmicutes, Nitrospirae and Planctomycetes. The phylum Proteobacteria is dominant in both bacterial libraries with a predominance of Gamma-Proteobacteria. A total of 31 and 25 phylotypes were obtained from 160 and 130 archaeal clones respectively, including Miscellaneous Crenarchaeotic Group, Marine Group Ⅰ and Ⅲ, Marine Benthic Group E, Terrestrial Hot Spring Crenarchaeota and Deep-sea Hydrothermal Vent Euryarchaeota. These results show a variety of clones related to those involved in sulfur cycling, suggesting that the cycling and utilization of sulfur compounds may extensively occur in the Lau Basin deep-sea hydrothermal ecosystem.     

Phylogenetic position and systematics of the wood‐associate limpet genus Caymanabyssia and implications for ecological radiation into deep‐sea organic substrates by lepetelloid gastropods

The gastropod superfamily Lepetelloidea represents an extremely diverse lineage in terms of their utilization of different deep‐sea organic substrates that include sunken wood, leaves, whale and fish bones, egg cases of sharks and rays, annelid tubes and detrital cephalopod beaks among others. They also inhabit cold seeps and hydrothermal vents, thus presenting an interesting case for the evaluation of such organic substrates as ‘stepping stones’ into these chemosynthetically nourished environments. Here we show the first molecular phylogeny of the Pseudococculinidae, a primarily wood‐dwelling family and the most speciose in Lepetelloidea. Special emphasis is placed on the genus Caymanabyssia, for which the only subfamily Caymanabyssiinae has been established, and a new species Caymanabyssia solis is described herein and compared with previously known taxa in order to reconsider the morphological characteristics of lepetelloids on wood. Bayesian and likelihood trees reconstructed using four‐gene sequences reveal that Pseudococculinidae sensu auctt. is a polyphyletic taxon that is grouped by shared plesiomorphic conditions of characters including the radula, a digestive organ, the morphology of which is often governed strongly by diet and feeding ecology. The newly reinterpreted families Pseudococculinidae and Caymanabyssiidae represent reciprocal sister clades as a basal radiation in Lepetelloidea. Sunken wood might thus have served as an ancestral habitat from which species on other substrates and vent and seep taxa were derived.     

渤海海冰微波散射特性研究

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.     

热液和冷泉10种无脊椎动物基因组大小测定及比较

基因组大小(或称C值)作为生物单倍体细胞中全套染色体的DNA总量,在一定程度上是恒定的,因而C值可以作为生物物种的一个特定参数。深海热液和冷泉为更好地理解C值与不同环境之间的关系提供了一个特征性的模型。本文采用流式细胞术,测定了来自热液和冷泉环境中的10种深海无脊椎动物的C值,其分布范围从0.87 pg到12.28 pg,其中,相比于软体动物和多毛类,甲壳生物基因组大小及变异均较大。对比热液和冷泉两个群落中共有种(深海偏顶蛤Bathymodiolus platifrons、柯氏潜铠虾Shinkaia crosnieri以及长角阿尔文虾Alvinocaris longirostris)的基因组大小,发现C值差异并不显著。同时,综合已有的数据,对深海化能极端环境与其他环境条件下的物种C值进行对比分析,结果显示深海化能极端环境下生物的基因组大小并没有发现明确的变化趋势。     

北半球夏季中高纬海洋声散射层分布研究

利用第八次北极调查走航ADCP后向散射强度数据,结合太阳高度、海冰密集度和实测水体环境参数数据,统计分析了中高纬海洋声散射层的时空变化特征。结果表明,纬度越高,声散射层在海表滞留时间越短,即使在极昼期间及全海冰覆盖海域,虽然其迁移幅度和后向散射强度减弱,但仍受太阳高度变化影响,且二者具有较强的时序相关性;在北极中央海域,不仅声散射层迁移活动较弱,且出现无明显散射层的情况,可能是因为该海域浮游动物和鱼类聚集度相对较低且迁移活动微弱,超出了本文所用ADCP的探测精度范围;从鄂霍次克海至白令海西南海域,往返ADCP数据均显示有两个后向散射强度上高下低,但垂直迁移时间同步的声散射层,且二者间距随纬度增加而逐渐减小并合为一体,这可能是由不同生活习性的海洋生物造成的。     

黄海、东海海区水体散射特性研究

半分析模型是水色遥感反演算法的研究热点,而水体后向散射系数对建立半分析水色反演模型是非常重要的参数.通过对黄海、东海海区的水体固有光学量测量数据进行分析,得到水体总后向散射系数与水体总散射系数的关系为乘幂关系,颗粒物后向散射系数随光谱变化的指数在高低浑浊度水体有很大差异,并初步得到黄海、东海海区水体的后向散射系数与总悬浮物浓度的关系,从而为水色半分析模型建立和水光学辐射计算提供一组散射特性模型.     

加强海域使用管理促进山东海洋经济发展

山东省委、省政府历来十分重视海洋资源的开发与管理，特别是海域的使用和管理，受到了各级政府的普遍重视。本文介绍了山东省海域使用管理的现状、管理工作中存在的问题，提出了加强海域使用管理的建议与对策。