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31.
Effects of cold eddy on phytoplankton production and assemblages in Luzon strait bordering the South China Sea 总被引:6,自引:0,他引:6
Yuh-Ling Lee Chen Houng-Yung Chen I. -I. Lin Ming-An Lee Jeng Chang 《Journal of Oceanography》2007,63(4):671-683
The biochemical effects of a cold-core eddy that was shed from the Kuroshio Current at the Luzon Strait bordering the South
China Sea (SCS) were studied in late spring, a relatively unproductive season in the SCS. The extent of the eddy was determined
by time-series images of SeaWiFS ocean color, AVHRR sea surface temperature, and TOPEX/Jason-1 sea surface height anomaly.
Nutrient budgets, nitrate-based new production, primary production, and phytoplankton assemblages were compared between the
eddy and its surrounding Kuroshio and SCS waters. The enhanced productivity in the eddy was comparable to wintertime productivity
in the SCS basin, which is supported by upwelled subsurface nitrate under the prevailing Northeastern Monsoon. There were
more Synechococcus, pico-eucaryotes, and diatoms, but less Trichodesmium in the surface water inside the eddy than outside. Prochlorococcus and Richelia intracellularis showed no spatial differences. Water column-integrated primary production (IPP) inside the eddy was 2–3 times that outside
the eddy in the SCS (1.09 vs. 0.59 g C m−2d−1), as was nitrate-based new production (INP) (0.67 vs. 0.25 g C m−2d−1). INP in the eddy was 6 times that in the Kuroshio (0.12 g C m−2d−1). IPP and INP in the eddy were higher than the maximum production values ever measured in the SCS basin. Surface chlorophyll
a concentration (0.40 mg m−3) in the eddy equaled the maximum concentration registered for the SCS basin and was higher than the wintertime average (0.29
± 0.04 mg m−3). INP was 3.5 times as great and IPP was doubled in the eddy compared to the wintertime SCS basin. As cold core eddies form
intermittently all year round as the Kuroshio invades the SCS, their effects on phytoplankton productivity and assemblages
are likely to have important influences on the biogeochemical cycle of the region. 相似文献
32.
Young-Ok Kim Eun Jin Yang Jung-Hoon Kang Kyoungsoon Shin Man Chang Cheol Soo Myung 《Ocean Science Journal》2007,42(1):9-17
The summer distributions of planktonic microbial communities (heterotrophic and phtosynthetic bacteria, phtosynthetic and
heterotrophic nanoflagellates, ciliate plankton, and microphytoplankton) were compared between inner and outer areas of Lake
Sihwa, divided by an artificial breakwater, located on the western coast of Korea, in September 2003. The semienclosed, inner
area was characterized by hyposaline surface water (<17 psu), and by low concentrations of dissolved oxygen (avg. 0.4 mg L1) and high concentrations of inorganic nutrients (nitrogenous nutrients >36 μM, phosphate <4 μM) in the bottom layer. Higher
densities of heterotrophic bacteria and nanoflagellates also occurred in the inner area than did in the outer area, while
microphytoplankton (mainly diatoms) occurred abundantly in the outer area. A tiny tintinnid ciliate, Tintinnopsis nana, bloomed
into more than 106 cells L1 at the surface layer of the inner area, while its abundance was much lower (103-104 cells L1) in the outer area of the breakwater. Ciliate abundance was highly correlated with heterotrophic bacteria (r = 0.886, p <
0.001) and heterotrophic flagellates (r = 0.962, p < 0.001), indicating that rich food availability may have led to theT. nana bloom. These results suggest that the breakwater causes the eutrophic environment in artificial lakes with limited flushing
of enriched water and develops into abundant bacteria, nanoflagellates, and ciliates. 相似文献
33.
Unlike in the open sea, the use of wind information for forecasting waves may encounter more ambiguous uncertainties in the coastal or harbor area due to the influence of complicated geometric configurations. Thus this paper attempts to forecast the waves based on learning the characteristics of observed waves, rather than the use of the wind information. This is reported in this paper by the application of the artificial neural network (ANN), in which the back-propagation algorithm is employed in the learning process for obtaining the desired results. This model evaluated the interconnection weights among multi-stations based on the previous short-term data, from which a time series of waves at a station can be generated for forecasting or data supplement based on using the neighbor stations data. Field data are used for testing the applicability of the ANN model. The results show that the ANN model performs well for both wave forecasting and data supplement when using a short-term observed wave data. 相似文献
34.
I. INTRODUCTION AHP resin is a new type of adsorbent and has been studied by the units concernedfor several years. There is little report about this work so far. AHP resin was synthesizedin aqueous phase with tetra-ethylene pentamine (TEPA), epichlorohydrin (ECH) andC-reagent as raw materials, and basic zinc carbonate (P_Z_n) and rubber solvent oil (120Gasoline) as pore-forming material. Compared with the technique of the amorphous lumpresin and that of the resin synthesized in oil phase, the new technique of resin synthesizedin aqueous phase manifests many advantages, such as raising the capacity of uranium-adsorption of the resin, simplifying the after-treatment process, reducing the cost, etc. Sea water, in which all kinds of cation and anion exist, is a system of electrolytes,and the concentrations of many ions are higher than the concentration of uranium for 相似文献
35.
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37.
MECHANISM OF URANIUM ADSORPTION ON AMIDOXIME RESIN 总被引:1,自引:0,他引:1
The mechanism of uranium adsorption from seawater by polyacrylamidoxime resin is investigated by means of the experiments of adsorption isotherm and adsorption rate. The uranium uptake increases with the adsorption temperature and varies with the pH of seawater. Thermochemical and kinetic calculation show that the enthalpy change (△H) and the activation energy (E) of the uranium adsorption are 42.4 42.4 kJ mol-1 and 41.2 kJ mol-1 respectively, indicating that the uranium adsorption on the resin proceeds via a certain complex chemical reaction in which the amidoxime group in the resin chelates uranyl ions. 相似文献
38.
应用荧光抗体技术检测牙鲆体内的河流弧菌 总被引:12,自引:0,他引:12
用灭活的河流弧菌(Vibrio fluvialis)抗原,注射免疫实验兔,制得凝集价为1∶5 120的抗血清。用试管凝集法检测了抗血清的特异性,再用免疫吸附法去除交叉反应,从而得到高效价、高特异性的抗河流弧菌血清。用所制备的抗血清在实验室中建立起河流弧菌荧光抗体检测技术(FAT),在荧光显微镜下可清楚地看到被标记的病原菌,整个检测过程只需3h。用河流弧菌感染牙鲆(Paralichthys olivaceus),24 h后,用FAT测定牙鲆的血液、肾脏和肝脏中的河流弧菌,在血液中河流弧菌的检出率最高,其次是肾脏,肝脏的检出率最低。以上结果表明:荧光抗体技术可以快速、灵敏、准确地检测出牙鲆体内的河流弧菌。 相似文献
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40.
A moving particle image velocimetry (PIV) system was successfully developed and used in a large towing tank for ship model tests to observe velocity fields near ship models. The experimental method involved adjustable optical devices for various test conditions and a special particle-seeding device. The streamwise and cross-streamwise flow fields of a yacht model and a tanker model were measured. Ship type, bottom shape, and towing speed were found to be the causes of problems affecting optical access and image quality. Possible solutions, deeper optical ducts, dark painting color, and pre-processed analysis method, were proposed and discussed. 相似文献