2001 Vol. 20, No. 3

Physical Oceanography,Marine Meteorology and Marine Physics
Hilbert transform and its application to modulation of capillary gravity waves
Yin Zhongbin, Lu Jun, Tian Jiwei
2001, (3): 309-315.
In this paper,the following important problem is answered:Under what condition can the Hilbert transform be put in the simple form.Then,using the Hilbert technique,it is demonstrated that,with some relative weak restrictions,the particle motion at the sea surface and energy transmission may be obtained from a wave record.The analysis shows that for the two-dimensional and narrow-band mo tion (or a physical phenomena,such as capillary waves breaking,which satisfy the narrow-band approx imation) the local kinetic energy fluctuates in time as the envelope squared multiplied by a constant factor and can be obtained directly from a wave record.It is pointed that the local fluctuations of the potential energy as well as the local fluctuations of the total energy can be separated into a slowly varying part and a more rapid oscillating part.Both parts can be evaluated by means of the Hilbert transform.Finally,a physical interpretation of the envelope of the two-dimensional capillary waves as well as the method for wave group analysis is presented.
Numerical simulation of characteristics of semidiurnal tidal waves in sea region around Taiwan
Sha Wenyu, Lu Xingang, Chen Xi, Zhang Wenjing
2001, (3): 317-330.
POM97,an oceanic model,has been used for the first time to the numerical study on the tidal waves of the sea regions around Taiwan.In this paper,we have got the result that the semidiurnal tidal waves of these area mainly are the co-operating tides which come from the south of 23°N of the western Pacific.Those semidiurnal tidal waves affecting the Taiwan Straits come respectively from the south and the north entrance of the channel,and the north tidal wave is stronger than the south one.The strongest tidal field is the area from the Meizhou Bay to the Xinhua Bay along the coast of Fujian Province,where the biggest amplitude of the M2 partial tide can reach 240 cm.The strongest tidal cur rent fields lie in the Penghu watercourse,where the maximum velocity of the M2 partial tide can arrive at 196 m/s.In the horizontal structure of the tidal currents,we have found that there is a stream dot in the north of the channel,besides,there still exist four new ones.As for the vertical structure,it mainly is biassed to the right at the surface,and to the left near the bottom layer.
Marine Meteorology
Relation of ice conditions to climate change in the Bohai Sea of China
Bai Shan, Liu Qinzheng, Wu Huiding
2001, (3): 331-342.
The ice conditions in the Bohai Sea and the northern Huanghai Sea greatly change from year to year with winter climate.Ice only covers below 15% of the the waters during the warmest win ter,while it covers more than 80% during the coldest winter.Ice observation and data acquisition are outlined in the paper.The ice-covered area,the position of ice edge and the ice grades give indication of the ice conditions.The local climate of the waters can be expressed by using the air temperature of the stations of Dalian and Yingkou.The variation of the ice condition indexes with the monthly mean air temperature at Dalian from 1952 to 2000 is shown,as well.The local climate and ice conditions in the waters are affected by many factors,such as,evolution of the general atmospheric circulation and the solar activity.The delayed correlation between the ice conditions and lots of the affecting factors is analysed in the paper.The ice conditions are continuously mild since the 1990s,that is relative to the tendency of the global warming.The ice condition variation of the Bohai Sea is related to the El Niño event and the sunspot period.The seasonal evolution of the ice conditions is also described in the paper.
Atmospheric correction for China's coastal water color remote sensing
Pan Delu, Mao Zhihua
2001, (3): 343-354.
The space satellite programs,such as CZCS/Nimbus-7,VHRSR/FY-1,OCTS/ADEOS and SeaWiFS/SeaStar,have demonstrated and proven that remote sensing is a powerful tool for understanding the spatial and temporal ocean color distribution.In general,there are two main technical keys in the processing ocean color satellite data.They are the atmospheric correction and the inversion of water-leaving radiance into water constituents (such as chlorophyll,suspended material and yellow substance) quantitatively.The SeaWiFS (sea-viewing wide field-of-view sensor) atmospheric correction algorithm for China's coastal waters is discussed.
First,the major advantages of SeaWiFS are introduced.Second,in view of the problems of the SeaDAS algorithm applying in China's coastal waters,the local atmospheric correction algorithms are discussed and developed.Finally,the advantages of the loc al algorithms are presented by the comparison of the results from two different algorithms.
Marine Chemistry
A discussion on typhoon occurred in the Haikou Bay and impact mechanism on seawater quality
Chen Chunhua, Li Qiaoxiang
2001, (3): 355-362.
Water quality parameters such as pH,DO,COD,PO4-P,SiO3-Si,NO2-N,NO3-N in the Haikou Bay were monitored respectively before and after Typhoon 9618 occurring on Sep.18,1996.Based on the statistics of typhoon in the Haikou Bay and numerical calculation of stormy current,the mechanism of water quality variation caused by typhoon is discussed.The typhoon impact on the Haikou Bay usually appears between July and November,most usually between August and October.The monitoring results before a typhoon were different from that.The stormy wave and windstorm cur rent stir up the sediment in near-shore bottom and make the bottom water mix with the surface water strongly,specially windstorm current with strong velocity at the head of the bay stirs up higher pollu tants sediment near sea area of sewage outfall,and heavy rain with typhoon carries the pollutants from land through the Nandu River to the Haikou Bay,so the contents of COD,PO4-P,NO2-N,NO3-N,SiO3 after a typhoon are higher than those before.Windstorm current is violent,which makes offshore high DO water exchange more frequently with inner bay water and oxygen in the air dissolves in sea water faster,so DO content after typhoon is higher than that before typhoon.This strong action of water exchange also causes lower pH change before and after the typhoon.
Exchange fluxes of nutrients between sediment and sea water in the Bohai Sea
Liu Sumei, Zhang Jing, Zhang Hong, Yu Jianhua
2001, (3): 363-370.
Investigations of sediment-water fluxes of nutrients in the Bohai Sea were carried out in September-October 1998 and April-May 1999.The exchange fluxes of nutrients between sediment and sea water were determined by incubating the core-top sediments with overlying water aerated with air.The benthic fluxes of NO3-,NO2-,NH4+,DIN,DON and TDN in the first cruise and the fluxes of NO3-,NO2-,NH4+,DIN,DON,TDN,PO43-,DOP and TDP in the second cruise were measured.The exchange fluxes of nutrients in fall were higher than in spring.The benthic nutrient fluxes represented 15%~55% of nutrient budgets in the Bohai Sea.
Application of long-chain alkenones and U37k values for paleotemperature estimation in the Arctic Chukchi Sea-Bering Sea area
Lu Bing, Chen Ronghua, Wang Zipan, Chen Jianfang, Liu Zhensheng
2001, (3): 371-381.
Long-chain alkenones were detected in samples of sea surface sediments from the Chukchi Sea and the Bering Sea areas,the Arctic Pole.The analysis result indicates that C37:3 methylketone is predominate in the long-chain alkenones from the Chukchi and Bering Sea sediments.The abundance of C37 to C39 unsaturated alkenones changes in an order of C37 > C38 > C39.Based on ∑C37/∑C38 ratio,the detected organism precursors of the long-chain alkenones are mainly coccolithophrid (Emiliania huxleyi).By the calibration relationship between U37k and U37k indices,the sea surface paleotemperature in these seas is estimated.The estimated values of U37k vary from 4.147℃ to 5.706℃,with a mean value of 5.092℃.
Marine Geology and Geomorphology
Glass inclusions in volcanic rocks in the Okinawa Trough back-arc basin:constraints on magma genesis and evolution
Yu Zenghui, Zhai Shikui, Li Xianzhong
2001, (3): 383-390.
The major elemnt compositions of glass inclusions in plagioclase and pyroxene phenocrysts of basalt and pumice in the Okinawa Trough back-arc basin are determined by electron microprobe.The results indicate that basalt and pumice are cognate and respectively represent the proluots at early stages of mgmtism and at late stage of crystal fractionation.The initial magrma in the trough is rich in H2O.The variation of H2O content in magma may play an important role in the magma evolution.Plagioclase is the mineral crystallized throughout the whole magrmatic process and accumulates in the zoned magma chamber.From these features it can he inferred that the initial magma in the Okinawa Trough,whose opening began in recent years,is serious ly affected by fluid or other materials carried by subducting slab and the geocbemical feature of volcanic rocks is in some degree similar to that of lavas in island-arc environments.
Geochemistry and environment evolution of Core E in the Laizhou Bay since last stage of Middle Pleistocene
Han Deliang, Yu Hongjun, Li Guanbao
2001, (3): 391-399.
Geochemistry analysis has been done on Core E (37°07'N,118°55'E; depth:82.1 m) taken from the Laizhou Bay in 1994.Nine kinds of invariable elements,15 kinds of microelements and the content of lime carbonate are measured by means of ICP.The results indicate that most of the in variable elements and microelements in Core E show significant changes in the boundary stratotype,and the ratios between elements (Mn/Fe,Sr/Ba,Ti/Al) in particular.So they can be used as characteristic indicator to stratigraphic division of Quaternary.The changes of invariable elements are primarily con trolled by the host minerals,and they mainly indicate the provenance as well as the sedimentation and depositional environment.Several elements,such as Fe,Al,Ca,Mg,Mn and Ti,are very sensitive to the provenance and environment.The distribution of microelements differs in four depositional periods:last stage of Middle Pleistocene,last interglacial period,last glacial period and Recent epoch,and espe cially in the "cold period" and "warm period".The loops in the cycle curves of the most microelements correspond with the sand bed sediments,among which there are six sand units representing "warm period" sediments,and one representing "cold period" sediments.The carbonate is on the high side in the aeolian silt sediments formed in the glacial lowering of sea level in Core E,but on the low side in the transgressive sand beds formed in the interglacial period.The content variation of carbonate has a direct bearing on the grain size and the styles of sediments,and is a good indicator to the climate,environment and stratigraphic division.
Marine Biology and Fishery
Identification of Porphyra lines using computerized DNA fingerprinting
Wang Bin, Jia Jianhang, Shi Jinfeng, Chen Yihua, Jin Demin, Xu Pu, Mei Junxue, Weng Manli
2001, (3): 401-407.
RAPD (Randomly Amplified Polymorphic DNA) analysis was performed with filaments of 15 Porphyra lines representing four important groups (P.yezoensis,P.haitanensis,P.katadai var.Hemiphylla and P.oligospermatangia:Eight stable and repeatable RAPD bands amplified with two primers,OPN-02 and OPJ-18,were selected for the construction of DNA fingerprinting.The RAPD results were scored based on the presence or absence of each of the 8 bands and then converted to computer language expressed with two digitals,1 and 0,which represented the presence (numbered as 1) or absence (numbered as 0) of each band,respectively.Based on these results,a model DNA fingerprint and a computerized DNA fingerprint were constructed.In the constructed DNA fingerprint,each Porphyra line has its unique fingerprinting pattern and can be easily distinguished from each other.Later,a software,named as PhGI,was designed based on this DNA fingerprinting.It can be used in practical Porphyra line identification.
Study on halotolerance of phyllosoma larva of Chinese spiny lobster (Panulirus stimpsoni Holthuis)
Chen Changsheng, Chen Zhengqiang, Hu Jiacai, Ye Zhaohong, Ji Dehua, Lan Liangchun
2001, (3): 409-415.
The halotolerance of phyllosoma larva of Chinese spiny lobster (Panulirus stimpsoni Holthuis) was experimentally studied in a man-made seawater of 13,15,19,23,27,31,35,39,43,47 and 49 salinity.The experimental results showed that phyllosoma lame survived for 4~6 d with a rate of 25.0% to 47.5% if seawater salinity was increased or decreased gradually from 31 to 49 or to 13 respectively.In a range of 23 to 39 salinity,the phyllosoma larva grew,developed and metamor phosed normally,the metamorphosis rate of which in Stages Ⅱ and Ⅲ being 85% and 48%,respec tively,when cultured in seawater of 31 salinity.It seems that some regular dispersion of larvae appeared in various salinities of seawater; In lower salinity,they mainly dispersed in the lower layer and in higher salinity,almost stayed in the upper and middle layers.Also,the results indicated that the phyllo soma larva of Chinese spiny lobster had a strong halotolerance to various salinities of seawater ranging from 15 to 47,in which 27 to 35 salinities were appropriate for larva growth and development.
Studies on island intertidal benthic ecology in Fujian
Zhou Shiqiang, Guo Feng, Tian Yue, Wu Lisheng, Li Rongguan
2001, (3): 417-425.
A total of 862 benthic species were identified in the island intertidal zone in Fujian,of which 734 species are animals and 128 species algae.Determination of Jaccard's similarity index of species was made on the intertidal communities around 11 major islands.Based on hierarchical clustering (WPGMA) and polar ordination,the benthic communities may be classified into three types:the estu arine type,the bay and harbour type and open sea type.The distribution of the benthic community is related to the location of the island and its habitats of which,salinity and hydrodynamics are the major factors controlling the distribution of the communities.
Analysis on genetic diversity of mangrove species of Sonneratia and relationship to plant introduction
Zhou Hantao, Lin Peng
2001, (3): 427-434.
RAPD markers were used to assess the relationships among 6 species of Sonneratia in the National Mangrove Nature Reserve of Dongzhai Harbor in Hainan.By using the 15 effective 10-oligonucleotide arbitrary primers,a total of 512 DNA bands were amplified,among which 297(58.01%:were polymorphic.Based on UPGMA cluster analysis of 512 DNA bands amplified by the thirty primers,a DNA molecular dendrogram was established,which divided 6 species of Sonneratia in to three main groups.Group A included 4 species:Sonneratia apetala,S.hainanensis,S.abla,S.ovata,and Group B:S.paracaseolaris and Group C:S.caseolaris only contained one species respectively.Group A could be divided into two subgroups,A1:Sonneratia apetala,S.hainanensis,S.ovata and A2:S.abla; Two populations of Sonneratia apetala,which were from Hainan and Fujian (introduced from Hainan) respectively,were compared by RAPDs.The phenotypic frequencies detected by the 15 primers were calculated and used to estimate diversity (H) within sub-populations.Fujian sub-population exhibited 0.669 and Hainan exhibited 0.671 variability.Shannon's index of phe notypic diversity was then used to partition the diversity within and between sub-populations compo nents.An assessment of the proportion of diversity present within sub-populations,Hpop/Hsp=0.933,compared with that between supopulations,(Hsp-Hpop)/Hsp=0.067,indicates that,on average,most of the diversity (93.3%:is detected within sub-populations; while only 6.7% between popula tions.The plant introduction of S.hainanensis and S.ovata,which have the nearer genetic distance with Sonneratia apetala,is also discussed.
Biomass of meiobenthic in the Bohai Sea, China
Guo Yuqing, Zhang Zhinan, Mu Fanghong
2001, (3): 435-442.
A grid of 22 stations,giving a broad geographic coverage of the Bohai Sea and the Bohai Strait was selected.Undisturbed sediments were collected from sampling stations during cruises in June 1997,in September/October 1998 and again in April/May 1999.Based on the results of Juario (1975),the average biornass,0.404 g/(m2·a) of meiofauna (including nematode,harpacticoida,bivalve larvae,polycheata and kinorhyncha) in the Bohai Sea is given and accounts for 4.5 percent of the macrofauna in the Bohai Sea.The horizontal distribution of the biomass of meiofauna showed that it was higher at the stations of middle east part of the Bohai Sea and the strait in 1998 and 1999 cruises and it decreased at the stations near to the strait mouth and increased at Station B1 in 1999 cruise.The annual average production in the Bohai Sea is 3.636 g/m2 calculated in term of the formula P=9B.Compared with the biomass of other sea areas in the world,the biomass of the Bohai Sea is similar but slightly lower.The individual average dry weight of nematodes given by different authors is analyzed.
A simulation analysis on pelagic-benthic coupling ecosystem of the northern Jiaozhou Bay, Qingdao, China
Wu Zengmao, Zhai Xuemei, Zhang Zhinan, Yu Guangyao, Zhang Xinling, Gao Shanhong
2001, (3): 443-453.