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991.
The molecular distribution of dissolved proteins in seawater from coastal marine environments in Uranouchi Bay, Kochi Prefecture, is first reported in this article. Occurrence of bacteria-derived dissolved proteins and their source bacteria were examined using a probe of the antibody (anti-Omp35La) against a porin outer membrane protein (Omp35La) of the fish pathogenic bacterium Vibrio (Listonella) anguillarum. The electrophoretograms of dissolved proteins from coastal seawater showed a large number of discrete and individual proteins overlapped each other over a wide range of molecular masses indicating active processes in coastal environments in transferring proteins from organisms to the inanimate dissolved protein pool. Among the dissolved proteins, 37 kDa- and 18 kDa-proteins reacted with the Omp35La. In order to isolate the source bacteria of such dissolved proteins, bacteria from seawater and diseased fish were screened by colony Western blotting with anti-Omp35La. The reactive strains were further examined in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)/Western blotting to verify the presence of Omp35La homologues among the outer membrane proteins of such strains. Outer membrane proteins reacting with anti-Omp35La were detected in only 4 strains of the 129 strains that were positive in the colony Western blotting. The level of possible source bacteria of 37 kDa- and 18 kDa-dissolved proteins was suggested to be 5–6 orders of magnitude lower than the total bacterial count. The present study leads us to hypothesize that a minor portion of the bacterial assemblage is responsible for the dissolved proteins in the coastal waters. 相似文献
992.
993.
Geochemical record of the Holocene Jomon transgression and human activity in coastal lagoon sediments of the San'in district, SW Japan 总被引:1,自引:0,他引:1
Coastal lagoon muds were analyzed to evaluate changes in sedimentary environments by the Jomon transgression from the lower to middle Holocene age and human activities. Core samples from Lake Shinji, Southwest Japan were utilized, which cover the entire Holocene Nakaumi Formation (ca. 23-m thick), and comprise the Lower, Middle, Upper and Uppermost members. Total sulfur (TS) contents and Fe2O3/Al2O3 ratios increase from the boundary of Middle and Upper members, which is 1 m below the Kikai-Akahoya (K-Ah) volcanic ash of 6300 years BP. This change coincides to the pollen flora zone boundary of the Pinus–Abies and the Cyclobalanopsis–Castanopsis, suggesting transition to a warming climate. Chemical index of alteration (CIA) values [(ratio of Al to Al+Ca+Na+K)×100] and Rb/K ratios also show gradual increase from the middle part of the Upper member, due to its derivation from highly weathered source material probably formed under warming and rainy condition. Al2O3/TiO2 and SiO2/TiO2 show little variation from the Lower to the Upper members, probably related to consistent feldspar composition in the source rocks, and homogeneously mixed clays. In the Uppermost member (from 1500 years), sharp increases in Ti/Zr and decreases in both Nb/Y and Zr/Y occurred, suggesting heavy mineral fractionation. This change was caused by iron sand processing called Kannanagashi and charcoal-making in the most mountainous regions. Soil erosion by these processes brought changes in mud composition, shown by the enrichment in Al2O3, and depletion in Zr and Cr. Human activities thus had severe impacts on sedimentary environments compared with the natural changes since the Jomon transgression. 相似文献
994.
中国沿海集装箱港口体系的形成演化机理 总被引:30,自引:5,他引:25
立足当今中国的现实,从现代经济学观点与港口地理学原理相结合的新视角,对沿海集装箱港口体系的形成演化机理进行理论探索,揭示出竞争与合作机制的交互作用是推动沿海集装箱港口体系形成演化的内在动力,并归纳演绎了由低级均衡→非均衡相对集中→非均衡高度集中→高级均衡的沿海集装箱港口体系的一般演化模式。实证分析表明,中国沿海集装箱港口体系正处于由非均衡相对集中向非均衡高度集中阶段演化的过渡时期,其动力机制主要有:转型经济的促进作用、政府行为的调控作用和中心枢纽港的极化作用。 相似文献
995.
996.
997.
A large sand bar develops in the inner Qiantang River Estuary, China. It is a unique sedimentary system,elongating landwards by about 130 km. Based on long-term series of bathymetric data in each April, July, and November since the 1960 s, this study investigated the morphological behavior of this bar under natural conditions and the influence of a large-scale river narrowing project(LRNP) implemented in the last decades. The results show that three timescales, namely the seasonal, interannual a... 相似文献
998.
中国近岸部分海域海水中金属络合配位体浓度的研究 总被引:7,自引:0,他引:7
采用阳极溶出伏安法对黄河口、青岛近海、大亚湾和南海海域海水中的金属络合配位体的浓度进行了测定,同时探讨了其分布规律与相关参量的关系.结果发现:南海海域海水中的金属络合配体的浓度稍高于其他3个海域,且都明显高于大洋水的浓度;在微表层存在富集现象;在垂直分布上表层最大,然后随深度增加而降低,在底层有较大值;各海域配位体的性质呈复杂性;铜的络合配位体浓度大于镉和铅;总的来说与世界其他海域的分布规律是一致的.同时发现铜络合配位体浓度与BOD(生化需氧量)、COD(化学需氧量)、DOC(溶解有机碳)及黏度存在显著的正相关性. 相似文献
999.
ADCP application for long-term monitoring of coastal water 总被引:3,自引:1,他引:2
Three kind of application of ADCP is reported for long-term monitoring in coastal sea. (1)The routine monitoring of water qualities. The water quality and ADCP echo data (600 kHz) observed in the long-term are analgzed at MT (Marine Tower) Station of Kansai International Airport in the Osaka Bay, Japan. The correlation between the turbidity and echo intensity in the surface layer is not good because air bubbles generated by breaking wave are not detected by the turbidity meter, but detected well by ADCP. When estimating the turbidity consists ofplankrton population from echo intensity, the effect of bubbles have to be eliminated. (2) Monitoring stirring up of bottom sediment. The special observation was carried out by using following two ADCP in the Osaka Bay, One ADCP was installed upward on the sea. The other ADCP was hanged downward at the gate type stand about 3 m above from the bottom. At the spring tide, high echo intensities indicating the stirring up of bottom sediment were observed. (3) The monitoring for the boundary condition of water mixing at an estuary. In summer season, the ADCP was set at the mouth of Tanabe Bay in Wakayama Prefecture, Japan. During the observation, water temperature near the bottom showed remarkable falls with interval of about 5~7d. When the bottom temperature fell, the inflow current with low echo intensity water appears at the bottom layer in the ADCP record. It is concluded that when occasional weak northeast wind makes weak coastal upwelling at the mouth of the bay, the combination ofupwelling with internal tidal flow causes remarkable water exchange and dispels the red tide. 相似文献
1000.