In planktonic diatom samples collected from Xiamen Harbour, Xiamen,Fujian,China from January 1983 to December 1984, two species and varieties are new to science and three species are recorded for the first time in China. New species is Tropidoneis constricta Li,Cheng et Chin sp. nov.,new variety is Fragilaria longissima v. protenta Li,Cheng et Chin var. nov.,new recorded species are Fragilaria heidenii Ostrup.F.oceanica Cleve and Thalassiosira punctigera Hasle.
This study reports the occurrence of anhydrite in hydrothermally altered pillow basalt (12°50.55'N, 103°57.62'W, water depth 2 480 m), which may have been produced in the basalt during seawater-basalt interaction in the laboratory. The existence of anhydrite in the altered basalt indicates extensive hightemperature hydrothermal alteration at the surface of seafloor pillow basalt. Microprobe analysis shows significant chemical zoning in the hydrothermally altered pillow basalt, in which Ca, Si and Al contents decrease and P, Fe, Mn, Cr and S contents increase from fresh basalt to altered basalt. The negative correlation between Rb-Sr and Li-Sr, and negative correlation between Li-Ca and Rb-Ca in the high-temperature vent fluids show that these fluids underwent anhydrite precipitation before fluid jetting due to mixing with seawater in the sub-seafloor. Based on these observations, we show that not all Ca in the anhydrite comes from basalt in the reaction zone, and that the basalts on the seafloor or in the upflow zone may also provide Ca for anhydrite.
Six species of Genus Cryptomonas from the East and South China Seas are reported. C.varibilis H. J. Huet L. P. Wu, C. zhanjiangensis H. J. Huet L. P. Wu and C. zhejiangensis H. J. Hu et Y. G. Li are described as new. C. profunda Butcher, C. pseudobaltica Butcher and C. chrysoides Butcher are reported as new record.
Using a neutron activation analysis technique,which involves gamma-spectrometry with a Ge (Li) detector coupled to a S40 multichannel analyzer and interfaced to a PDP-11 computer,we determined thirty-eight elements in sediments from the lower reach (downstream from Jinan) and estuary of Huanghe.The results are discussed in this paper. From inter-elemental correlations,it ts found that a large number of metals (Mn,As,Co,Cr,Cs,Rb,Sc,Ti,Ta,V and Zn) correlate positively with Fe.Ba and Ca correlate positively with Al.Whereas some elements (e.g.,Ti and lanthanides) show no correlation with either Fe or Al.On the other hand,Hf and Zr show a negative correlation with Fe.Elements which tend to be scavenged by Fe and Al colloids or suspended particles are enriched in sediments at the Huanghe Estuary relative to its lower reach.On the other hand,the contents of some elements (e.g.,Zr,Hf,U,Ba,etc.)are higher in sediments from the lower reach of Huanghe than in the estuarine sediments,which may be related to the sorting durig deposition of source materials.
The transfer of 137Cs, 60Co along Platymonas sp., Brachionus plieatilis Müller and Tilapia mossambica Peters was studied by using the tracer methods of both 137Cs and 60Co with Ge (Li) Gamma ray detector and S-80 type multichannel-analyser for measuring the radioactivity of the sample. The experiment was carried out in four groups and the period of the experiment was fifteen days. It was found that 60Co could be transferred along seawater→Platymonas→Brackionus→Tilapia, and that 137Cs could only be transferred from seawater to Platymonas. 137Cs was not accumulated by Brachionus in any group of the experiment. Brachionus ingested 60Co mainly from Platymonas, when 60Co was ingested by Tilapia; Brachionus played an important role in the transfer and the Tilapia ingested 137Cs mainly from seawater.
In the present paper, by introducing the effective wave elevation, we transform the extended elliptic mild-slope equation with bottom friction, wave breaking and steep or rapidly varying bottom topography to the simplest time-dependent hyperbolic equation. Based on this equation and the empirical nonlinear amplitude dispersion relation proposed by Li et al. (2003), the numerical scheme is established. Error analysis by Taylor expansion method shows that the numerical stability of the present model succeeds the merits in Song et al. (2007)'s model because of the introduced dissipation terms. For the purpose of verifying its performance on wave nonlinearity, rapidly varying topography and wave breaking, the present model is applied to study:(1) wave refraction and diffraction over a submerged elliptic shoal on a slope (Berkhoff et al., 1982); (2) Bragg reflection of monochromatic waves from the sinusoidal ripples (Davies and Heathershaw, 1985); (3) wave transformation near a shore attached breakwater (Watanabe and Maruyama, 1986). Comparisons of the numerical solutions with the experimental or theoretical ones or with those of other models (REF/DIF model and FUNWAVE model) show good results, which indicate that the present model is capable of giving favorably predictions of wave refraction, diffraction, reflection, shoaling, bottom friction, breaking energy dissipation and weak nonlinearity in the near shore zone.
Trace elemental associations and Sr-Nd isotopic compositions are of important to recognition of biogenic material from mixed marine sediments.The foraminifera shell from the Okinawa Trough strongly enrichesSr, P, Mn andBa, enriches Li, U, Th, Sc, Co, Cu, Pb, Zn, Cr, Rb, Y, Sb and light rare earth elements, slightly enriches V, Ga, Zr, Nb, Cd and middle rare earth elements, is short of Mo, In, Sn, Cs, Hf, Ta, W, Ti, Bi and heavy rare earth elements.The mechanism of elemental enrichment in forminifera is the concentrations of trace elements in sea water and selective absorption of trace elements during foraminifera living, as well as the geochemical affinity between major elements and trace elements.The REE (rare earth elements) partition pattern of foraminifera shell of the Okinawa Trough shows enrichment of middle rare earth elements with slightly negative Ce anomaly, which are different from those of foraminifera of the Pacific Ocean.The Sr, Nd isotopic ratios of the Okinawa Trough foraminifera are 0.709 769 and 0.512 162, respectively, which are different not only from those of oceanic water, but also from those of river water of China's Mainland, the former is slightly higher than those of oceanic water, but much lower than those of river water; the latter is slightly lower than those of oceanic water, but higher than those of river water, demonstrating that the Okinawa Trough sea water has been influenced by river water of China's Mainland.