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1.
Bacteria abundance, chlorophyll a, ATP and POC concentrations and respiration rates of microorganisms in the Changjiang Estuary and the plume were determined in July 1986. The high values of bacteria abundance occurred in the river mouth in association with suspended matter. It is assumed that bacteria were the major contributor to ATP and the main consumer of dissolved oxygen, and that the relationship between ATP and POC was present in that area. In the dilution zone (salinity; 25-30), instead of bacteria, phytoplankton was the major contributor to ATP and respiration rates, due to diatom bloom. Close relationships between Chi a and ATP, and ATP and POC were observed. Contribution of microbial carbon to POC was also estimated. 相似文献
2.
Wei Shouqing 《海洋学报(英文版)》1991,10(3):480-480
A study was made on the polyculture of the red algae Gracilaria tenuistipitata Chang et Xia f. Liui Zhang et Xia, f. nov. , the shrimp Penaeus penicillatus Alcock and the mud crab Scylla serrata (Forskal) . The photosynthesis of the algae produces the oxygen on which the shrimp and the crab breathe. The algae are the reproductive place of the organism for the food of the shrimp and the carb, also is the shelter of the shrimp and the crab. The shrimp and the crab regard the algae as the vegetable 相似文献
3.
《中国海洋工程》1993,(4)
The Seminar on the Development of Port and Coast in the Mainland and Taiwan was heldfrom October 15th to 20th, 1993 in Hohai University, Nanjing, China, under the sponsorship ofHohai University and National Cheng Kung University, Tainan, and under the co-sponsorshipof Nanjing Hydraulic Research Institute and Jiangsu Society of the Mainland and Taiwan Rela-tionship. The aim of the Seminar is to strength the academic exchanges in the fields of port andcoastal engineering, to promote cooperation in science and technology, to benefit the develop-ment of construction as well as science, technology and education in port and coastal engi-neering in the Mainland and Taiwan of China. The main topics covered are in four aspects: 相似文献
4.
- This paper deals with species composition, seasonal change and horizontal distribution of the Hydromedusae (Hyd.), Siphonophores (Sip.) and Ctenophores (Cte.) and their relationship to the environmental factors. Materials from 17 stations in the Xiamen Harbour and adjacent waters were taken once monthly for the period from Sep. 1980 to Aug. 1981. The results indicate that for the dominant species of Phialidium folleatum, Lensia subtiloides and Pleurobrachia globosa , the total annual number of species has one peak and the total annual number of individual has one peak and two secondary peaks. On the basis of their ecological characteristice, the Hydromedusae, Siphonophores and Ctenophores found in the region investigated may be divided into the following ecological groups: estuarine group, neritic group and oceanic group. Their seasonal succession is correlated with the relative intensity of several water systems. 相似文献
5.
According to B.L. Berry’s “harmonic model,” any natural or social process is a superposition of several cosmic rhythms. The
author assumes that stability of these rhythms allows prediction of earth phenomena over an unlimited time. We show that the
statistical criteria supposedly substantiating the harmonic model were applied incorrectly. The initial data for the analysis
were biased and selected incompetently; the adequacy of the methods used was not verified. Predictions of natural catastrophes
(earthquakes, weather anomalies, etc.) and various social events according to Berry’s model are unsatisfactory. Statistics
do not confirm that these predictions are at least slightly better than random guessing. Berry’s model is unacceptable; it
is untenable both in detail and in general. 相似文献
6.
The algae of M. andicava, E. linza and U. pertusa were induced for four days in artificialseawater colltaining 0.5 ppm of Cd~(2+), respectively. Then each of them was homogenizedand isolated. The final soluble fraction was chromatographed in a Sephadex G--75 column. 相似文献
7.
INTRODUCTIONInordertostudythemarinesedimentationoftheChukchiSeaandBeringSeaandgathertheinformationofpaleoceanographyandpaleoenvironment,theFirstChineseNationalArcticResearchExpeditionTeamcollectedbenthonicmolluscansamplesintheChukchiSea ,BeaufortSeaandBeringSeafromJuly 1sttoSeptember 9th ,1 999byicebreakerXuelong .ItwasnotonlythefirstsamplingthatChinesescientistscollectedmolluscaremainsinabove mentionedar eas,butalsooneofinvestigationsinasinglecruisewithhighersamplingrateandalotofb… 相似文献
8.
Demidov A. B. Gagarin V. I. Artemiev V. A. Arashkevich E. G. Makkaveev P. N. Shchuka S. A. Khrapko A. N. Grigoriev A. V. Vorobieva O. V. Konyukhov I. V. Fedorov A. V. 《Oceanology》2020,60(2):189-204
Oceanology - The vertical distribution of phytoplankton primary production (PP) and chlorophyll a (Chl) was studied based on the data carried out in August–September 2015, 2017, and 2018. The... 相似文献
9.
By means of physicochemical modeling with the Selector software package, a model for the mixing of riverine water (pH = 7.02) and seawater was compiled and calculated. The Razdol’naya River-Amur Bay (Sea of Japan) system was assessed as an example. By means of the MINTEQA2/PRODEFA2 software package, the role of the sorption processes in riverine and marine waters, as well as in the zone of their mixing, was ascertained. The physicochemical migration forms of microelements (arsenic, vanadium, chromium, cobalt, and mercury) in the waters of the geochemical system considered and their behavior in passing through the geochemical barrier were established. 相似文献
10.
Barremian–Aptian organic-rich shales from Abu Gabra Formation in the Muglad Basin were analysed using geochemical and petrographic analyses. These analyses were used to define the origin, type of organic matters and the influencing factors of diagenesis, including organic matter input and preservation, and their relation to paleoenvironmental and paleoclimate conditions. The bulk geochemical characteristics indicated that the organic-rich shales were deposited in a lacustrine environment with seawater influence under suboxic conditions. Their pyrolysis hydrogen index (HI) data provide evidence for a major contribution by Type I/II kerogen with HI values of >400 mg HC/g TOC and a minor Type II/III contribution with HI values <400 mg HC/g TOC. This is confirmed by kerogen microscopy, whereby the kerogen is characterized by large amounts of structured algae (Botryococcus) and structureless (amorphous) with a minor terrigenous organic matter input. An enhanced biological productivity within the photic zone of the water columns is also detected. The increased biological productivity in the organic-rich shales may be related to enhanced semi-arid/humid to humid-warm climate conditions. Therefore, a high bio-productivity in combination with good organic matter preservation favoured by enhanced algae sizes are suggested as the OM enrichment mechanisms within the studied basin. 相似文献
11.
D. I. Glukhovets O. V. Kopelevich I. V. Sahling V. A. Artemiev L. A. Pautova E. K. Lange M. D. Kravchishina 《Oceanology》2017,57(3):410-418
The article presents the results of shipboard and satellite measurements in the surface layer of the Baltic, Norwegian, and Barents seas during legs from the Baltic to the White Sea in June–August 2014–2016. Special attention is paid to marine phytoplankton blooms of cyanobacteria in the Baltic Sea and coccolithophores in the Barents Sea. No blooms were found in the Norwegian Sea. The efficiency of combined application of in situ and satellite optical methods for studying the parameters of phytoplankton blooms is shown. 相似文献
12.
In the seawater and sediments of the ocean, there exist huge quantities of bacteria whose living activities cause various chemical reaction processes. It is demonstrated that microorganisms play a fundamental role on chemical changes of the sediments and diageneses. Over the last twenty years, great interest has been increased about the role of deep-sea bacteria in the ferromanganese sedimentary process. Much work has been done on this aspect in the Atlantic Ocean, the Baltic Sea and the Pacific O- 相似文献
13.
Cenk Yalt?rak Umut B. ülgen Cengiz Zabc? Sven Oliver Franz Sena Ak?er ?n Mehmet Sak?n? M. Nam?k ?a?atay Bedri Alpar Kurultay ?ztürk Cemal Tuno?lu Selma ünlü 《Geo-Marine Letters》2012,32(3):267-274
The identification of past connection routes between the Black Sea and the Sea of Marmara, other than the traditional one through to the Bosphorus Strait, would be of considerable interest to the international scientific community. Nazik et al. (Geo-Mar Lett 31:75?C86 (2011) doi:10.1007/s00367-010-0216-9) suggest the possibility of two alternative waterway connections via lakes Sapanca and ?znik. Their Black Sea to Sea of Marmara multi-connection hypothesis, which is based on undated marine fossils collected in both lakes from surficial grab samples, conflicts with many earlier studies. In this contribution, the hypothesis and the underlying data are discussed in the light of previous tectonic, sedimentological and limnological findings showing that it is impossible to have had marine connections through lakes Sapanca and ?znik during the last 11.5?ka. Global sea-level trends and tectonic uplift rates would accommodate a connection between the Sea of Marmara and Lake ?znik in the middle Pleistocene. Uplift rates for the northern block of the North Anatolian Fault, when compared with the global sea-level curve, clearly indicate that there cannot have been a connection through the ?zmit Gulf?CLake Sapanca?CSakarya Valley for at least the past 500?ka. Moreover, borehole sediments along the western shores of Lake Sapanca, which reach down to the bedrock, do not contain any marine fossils. 相似文献
14.
1Introduction Heterotrophicmicrobesarenowconsideredtobe significantcomponentsofthestructureandfunctionof marinepelagicecosystems.Heterotrophicbacteriacon- stituteamajorpoolofbiomassinopenecosystem (WilhelmandSuttle,1999).Theyconsumealargepor- tionofprimaryproduction(Li,1998;Sherryetal., 2002;Lietal.,2004),andtheymineralizemostofthe dissolvedorganiccarbonthattheyconsume(Azamet al.,1983;Richetal.,1997;Azam,1998).Therolesof planktonicprotists,suchasheterotrophicflagellates andciliates,inmicro… 相似文献
15.
1IntroductionEdwardsiellahas been recognized as a world-wide-occurring pathogen of numerous marine fishspecies,and edwardsiellosis has been recorded in adiverse array of fish species,including chinooksalmonOncorhynchus tshawytschaL.(Amandi etal.,1982),cha… 相似文献
16.
Atike Nazik Engin Meri? Niyazi Av?ar Selma ��nl�� Vildan Esenli Erkan G?ka?an 《Geo-Marine Letters》2011,31(2):75-86
In this study, the fossil microfaunal composition of 28 Recent sediment samples from Lake İznik and 19 samples from Lake Sapanca
was investigated. The presence of at least ten marine ostracod and 23 foraminifer species in the sediments of Lake İznik,
and at least one marine ostracod and two foraminifer species in the sediments of Lake Sapanca confirm that these lakes must
have been connected to the world ocean sometime during the late Quaternary. The most obvious former link between these lakes
and the Mediterranean Sea would have been via the Marmara Sea with an eastward extension of the Gemlik and İzmit bays. The
proximity of Lake Sapanca to the lower course of the Sakarya River, however, also supports earlier suggestions that there
may have been a temporary connection with the Black Sea via this river valley. Whatever the case, the findings of this study
clearly demonstrate that vertical tectonic movements need to be taken into account when reconstructing the late Quaternary
sea-level history of this region. 相似文献
17.
In their discussion of our 2011 paper dealing with possible waterways between the Marmara Sea and the Black Sea in the ??late?? Quaternary, based on data from ostracod and foraminifer assemblages in lakes ?znik and Sapanca, Turkey, Yalt?rak et al. (Geo-Mar Lett 32:267?C274, 2012) essentially reject the idea of any links whatsoever, be they between the Marmara Sea and the lakes ?znik and Sapanca, or further to the Black Sea via the valley of the Sakarya River. The evidence they provide in support of their view, however, is essentially circumstantial, in part conjectural, and also inconclusive considering the findings in favour of linkage between the Marmara Sea and the lakes at the very least, while the proposed connection with the Sakarya River valley remains speculative because of the lack of unambiguous data. On the other hand, Yalt?rak et al. (Geo-Mar Lett 32:267?C274, 2012) do raise valid points of concern which deserve careful future investigation, the most important being the possibility of sample contamination from dumped marine sediment used for construction purposes along some parts of the shore of Lake ?znik. We agree that a concerted multidisciplinary effort is required to address the many unresolved issues in connection with the potential waterways proposed by us and others before us. 相似文献
18.
By use of bathymetric chart,recent change of the riverbed in the North Passage of the Yangtze Estuary has been studied in this paper.The main channel of the upper,middle and lower(section)in the North Passage has been successively eroded and its groin field significantly deposited.At the same time,sediment has been deposited on the entrance region.Erosion and deposition had responded rapidly to the construction of the regulation engineering.There was about one year duration of lagging between erosion in the deep channel and the construction of the regulation engineering.The siltation lag of time in the groin field varied with the initial depth,but the average deposited thickness was about 0.5 m per year.Volumetric analysis demonstrates that there is a increasing trend of siltation in the North Passage after 2002,because of the difference in duration and quantity between erosion in the deep channel and deposition in the groin field.The water volume of the North Passage was reduced by ≈9%(280 million m3)between 2002 and 2006.Sediment budget reveals that the main sediment deposited in the North Passage takes its source from the river and the ocean.The decreasing water volume was attributable to shoaling in the groin field.Its triggering factors for increased sedimentation are the navigational improvements(jetties and groins)after 1998,which altered the passage boundary and destroyed the equilibrium state on the average ebb and flood sediment fluxes.The establishment of a stable estuary is attributed to a reduction in depth of the groin field.The forecast on the sediment deposition quantity and continuous infilling time in the groin system is about 325×106m3 and 6～7 years,respectively. 相似文献
19.
Basic characteristics and forming mechanism of the sharp thermocline in the Bohai Sea, Huanghai Sea and northern East China Sea 总被引：2，自引：0，他引：2
Zhao Baoren 《海洋学报(英文版)》1989,8(4):497-510
- On the basis of the fact that the sharp thermocHne in the Bohai Sea and the northern Huanghai Sea is often distributed in the deep valley areas, it has been long thought that the reason of the formation of the sharp thermocHne is that the cold water can be easily kept in valleys. But recent investigations carried out in the southern Huanghai Sea in summer show that all of the sharp thermocHne areas were distributed in the shallow sloping-bottom areas but not in the deep valley areas. Only in autumn would the sharp thermoclines translate to the deep valley areas. In summer, they are characterized by shallow upper mixing layer and thin thickness in the southern Huanghai Sea. In addition to entrainment coming from lower boundary of upper mixing layer the entrainment from upper border of bottom homogeneous layer induced by tidal mixing also plays an important role in the growth and decay of thermoclines in these seas. 相似文献
20.
Study on interaction between the coastal water, shelf water and Kuroshio water in the Huanghai Sea and East China Sea 总被引：3，自引：3，他引：3
The main processes of interaction between the coastal water, shelf water and Kuroshiowater in the Huanghai Sea (HS) and East China Sea (ECS) are analyzed based on the observation and study results in recent years. These processes include the intrusion of the Kuroshio water into the shelf area of the ECS, the entrainment of the shelf water into the Kuroshio, the seasonal process in the southern shelf area of the ECS controlled alternatively by the Taiwan Strait water and the Kuroshio water intruding into the shelf area, the interaction between the Kuroshio branch water, shelf mixed water and modified coastal water in the northeastern ECS, the water-exchange between the HS and ECS and the spread of the Changjiang diluted water. 相似文献