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Research status and development trends of natural products from marine microorganisms
MA Lili, TIAN Xinpeng, LI Guiju, ZHAO Yanqiang, YIN Jianping
Journal of Tropical Oceanography    2021, 40 (5): 134-146.   DOI: 10.11978/2020104
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Because of their unique habitat and metabolic pathways, marine microorganisms can produce a variety of bioactive substances with novel structures and functions, which make natural products from these marine microorganisms become a research hotspot of new marine drugs. Combining the methods and perspectives of bibliometrics, we review in this paper the research status of natural products from marine fungi and marine bacteria, the artificial synthesis of natural products of marine microorganisms, the biological activity and druggability evaluation of natural products from marine microorganisms, to clarify the current status and development trend of natural products from marine microorganisms.

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Cited: CSCD(2)
Relationship between the Western Pacific Subtropical High and sea-surface temperature anomaly
FAN Lei,LIU Qin-yu
Journal of Tropical Oceanography    2009, 28 (5): 83-88.   DOI: 10.11978/j.issn.1009-5470.2009.05.083
Abstract3016)      PDF(pc) (6368KB)(2211)       Save

The authors study the relationship between the Western Pacific Subtropical High (WPSH) and sea-surface temperature (SST) anomaly in each selected key area based on lag correlation analysis. The lag correlation indicates that the eastern Pacific SST in winter correlates with the WPSH anomaly two or three months later to the highest degree; the SST in the tropical Indian Ocean and the WPSH anomaly in the corresponding period significantly correlates with each other in winter; and the SST in the western Pacific in winter and spring negatively correlates to the WPSH anomaly in the corresponding period. In addition, the SST in the northern Pacific in winter and spring negatively correlates with the WPSH anomaly one to two months earlier. The largest positive correlation between the Atlantic Warm Pool and the WPSH anomaly in the corresponding period occurs in June. Regarding to the southern Pacific, the WPSH anomaly in winter negatively correlates with the SST anomaly from last autumn to next spring. To sum up, in winter and spring, SST anomaly is almost fully responsible to the annual variation of the WPSH anomaly, but in summer and autumn, the influence of SST on the WPSH is constrained to a small scale.

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Cited: Baidu(8) CSCD(4)
Preliminary investigation on the bacteria diversity coupled with the monsoon forced circulation in the South China Sea
Jie LI, Zhiyou JING, Si ZHANG
Journal of Tropical Oceanography    2018, 37 (6): 1-15.   DOI: 10.11978/2017127
Abstract2748)   HTML1498)    PDF(pc) (1521KB)(1931)       Save

Ocean dynamic processes in the South China Sea driven by the monsoon are characterized by seasonal and multi-scale variations, which have significant impacts on the evolution of marine ecosystems. Marine bacteria, as an important component of material cycle and energy flow in marine ecosystems, have active responses to the environmental changes associated with multi-scale dynamic processes. The interdisciplinary research on microbial community structures, their dynamic variation and associated physical processes is one of the hot issues in marine sciences, which combines marine microbiology, microbial ecology and physical oceanography. Based on the primary results of the Key Research Program, "Study on bacteria diversity coupled with the monsoon circulation in the South China Sea and significance in microbial oceanography" supported by the National Natural Science Foundation of China, we discuss in this paper current research progress, including coastal upwelling, seasonal thermal fronts, mesoscale eddy, sub-mesoscale processes, and their potential impacts on the marine bacterial diversity and local ecosystem in the South China Sea.

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Cited: CSCD(1)
Impacts, challenges and opportunities of global climate change on mangrove ecosystems
WANG Youshao
Journal of Tropical Oceanography    2021, 40 (3): 1-14.   DOI: 10.11978/YG2020006
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Mangroves are salt-tolerant plants of tropical and subtropical intertidal regions distributed mainly between latitudes 25°S and 25°N globally. They have high productivity, high return rate, high decomposition rate, and high resistance, which cover roughly 60%-75% of the world’s tropical coastlines. Mangroves are distributed over more than 118 countries with a total area near 17 million hectares in the world, and their net primary productivity is up to 2000 gC·m-2·a-1. They form a widespread ecosystem and also play an important role in the process of global change. Global climate change has aroused great concerns in the last three decades. Mangroves are a vulnerable and eco-sensitive ecosystem along tropical and subtropical intertidal shores that are regulated by both lands and oceans. They are one of the typical marine ecosystems that can be affected by global climate change. As an important ecological barrier along the coast, global climate change will also affect the survival and distribution of mangroves in the world. The present paper briefly reviews the impacts of global climate change on mangroves in terms of global warming, sea-level rise, atmospheric CO2 concentration increase, and extreme weather. The ongoing global climate change will bring great challenges and opportunities to research, maintenance, and development of mangroves in the future.

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Simulation of potential tsunami hazards in the South China Sea
PAN Wen-liang,WANG Sheng-an,CAI Shu-qun
Journal of Tropical Oceanography    2009, 28 (6): 7-14.   DOI: 10.11978/j.issn.1009-5470.2009.06.007
Abstract2698)      PDF(pc) (4945KB)(1917)       Save

Based on comprehensive consideration of topography, geological structureseismological features and historical records, the authors analyze the hazardous tsunamigenic zones in the South China Sea and discuss the possibility of potential tsunami hazards in the region. A tsunami induced by a hypothetical earthquake in the Manila Trench is simulated using a nested 3-layer grid system with high resolution. Each grid area in the grid system can be configured with its own type of coordinate system depending on its coverage, simulation parameters as well as the governing equations in terms of the characteristics at different stages of tsunami propagation. This flexible, nested grid setup allows for a balance between computational accuracy and efficiency. The simulation resultssuch as the calculated travel time map, maximum surface elevation and water height series at four virtual gauges, indicate that the tsunami hazards could happen on the coasts off South China. Further research is necessary to determine the need for a monitoring system of tsunami in the region.

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Cited: Baidu(22) CSCD(10)
Environmental pollution in the Pearl River Estuary: a review
HUANG Xiao-ping,TIAN Lei,PENG Bo,ZHANG Da-wen
Journal of Tropical Oceanography    2010, 29 (1): 1-7.   DOI: 10.11978/j.issn.1009-5470.2010.01.001
Abstract2693)      PDF(pc) (339KB)(3808)       Save

Environmental pollution is serious in the Pearl River Estuary due to human activities and an increasing attention has been paid to the pollution in this region. This paper mainly reviews the eutrophication characteristics and the pollution patterns of persistent toxic substances (PTS, including heavy metals and persistent organic pollutants—POPs) in the water. Results in-dicate that the excessive input of nitrogen and phosphate has led to the high eutrophication in the water. Eutrophication plays an important role in triggering red tides. The coupling effect of the water stratification and eutrophication leads to the seasonal hypoxia in certain areas of the estuary. PTS mainly accumulate in sediment and organisms. The records of pollutants in sedi-ment cores reflect that pollutant accumulation in sediments is closely related to the rapid economical development of the Pearl River Delta in the past three decades. Finally, the critical issues of research are put forward on the environmental pollution of this area in the future, which include biotransformation of pollutants in tissues and bioaccumlation in food chain, the combined pollution of various pollutants in eutrophic water, mechanisms of microbial biodegradation of pollutants, pollution control strategy, among others.

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Cited: Baidu(55) CSCD(18)
An improved, SSH-based method to automatically identify mesoscale eddies in the ocean
WANG Xin, DU Yun-yan, ZHOU Cheng-hu, FAN Xing, YI Jia-wei
Journal of Tropical Oceanography    2013, 32 (2): 15-23.   DOI: 10.11978/j.issn.1009-5470.2013.02.002
Abstract2566)      PDF(pc) (1543KB)(1969)       Save

Mesoscale eddies are an important component of oceanic features. How to automatically identify these mesoscale eddies from available data has become an important research topic. Through careful examination of existing methods, we propose an improved, SSH-based automatic identification method. Using the inclusion relation of enclosed SSH contours, the mesoscale eddy boundary and core(s) can be automatically identified. The time evolution of eddies can be examined by a threshold search algorithm and a tracking algorithm based on similarity. Sea-surface height (SSH) data from Naval Research Laboratory Layered Ocean Model (NLOM) and sea-level anomaly (SLA) data from altimeter are used in the many experiments, in which different automatic identification methods are compared. Our results indicate that the improved method is able to extract the mesoscale eddy boundary more precisely, retaining the multiple-core structure. In combination with the tracking algorithm, this method can capture complete mesoscale eddy processes. It can thus provide reliable information for further study of reconstructing eddy dynamics, merging, splitting, and evolution of a multi-core structure.

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Cited: CSCD(6)
Assessment of the Pearl River Estuary pollution by water comprehensive pollution index and biodiversity index
ZHANG Jing-ping,HUANG Xiao-ping,JIANG Zhi-Jian,HUANG Dao-jian,HUANG Liang-min
Journal of Tropical Oceanography    2010, 29 (1): 69-76.   DOI: 10.11978/j.issn.1009-5470.2010.01.069
Abstract2405)      PDF(pc) (1159KB)(3924)       Save

Two cruises were carried out to investigate the water quality and ecological status in the Pearl River Estuary in July 2006 and March 2007. Water comprehensive pollution index and biodiversity index (including phytoplankton, zooplankton and benthos) were used to assess the pollution status. In addition, rationality of the assessment by using the biodiversity index was also discussed. The results indicated that the pollution degrees of the Pearl River Estuary were between moderate to severe. Water comprehensive pollution index showed that it was at a severely polluted status both in wet and dry seasons. Biodiversity index led to different results, which varied from lightly-moderate pollution to severe pollution. Among the three biodiversity indices, we considered that zooplankton diversity index was more congruent than the other two indices in pollution status assessment. However, the evaluation criteria should be verified and modified in future study. It was concluded that assessment for the environment quality and ecological status by using different biodiversity indices may come to a varied result, and a simple conclusion could not be hastily educed but should be associated with physicochemical factors.

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Cited: Baidu(47) CSCD(31)
The impaction of typhoon on seafloor ambient noise by analyzing the OBS recording data
AO Wei, ZHAO Ming-hui,RUAN Ai-guo,QIU Xue-lin
Journal of Tropical Oceanography    2009, 28 (6): 61-67.   DOI: 10.11978/j.issn.1009-5470.2009.06.061
Abstract2363)      PDF(pc) (4891KB)(1800)       Save

Ocean Bottom Seismometer (OBS) deployed in the seafloor can record information of ocean ambient noise, and typhoon can generate elastic waves propagating through the seafloor directly or indirectly. These factors cause great changes on OBS recording data to some extent. The OBS data during the process of typhoon was analyzed, and the methods of optimum filter were used in order to separate signals. After those work, we found that wind wave and ground swell were well recorded by short-period OBSs for the first time, and a new mode which typhoon affected seafloor ambient noise was put forward. We get three preliminary conclusions from above analysis: (1) Wind wave and ground swell caused by typhoon have their own distinctive modes to affect seafloor ambient noise;(2)The range and extent of seafloor ambient noise are obviously different which have been strengthened by two above waves;(3)Short-period OBSs can clearly record the information of ground swell, whose dominating period is 6—8 seconds and its energy is generally steady (we call it “8-second phenomenon); These results will have great significance for the future research on marine seismology and other aspects of oceanography.

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Cited: Baidu(4) CSCD(5)
Two sea-surface warming events in the South China Sea during and after El Nino
HUANG Zhuo,XU Hai-ming,DU Yan,XIE Qiang
Journal of Tropical Oceanography    2009, 28 (5): 49-55.   DOI: 10.11978/j.issn.1009-5470.2009.05.049
Abstract2363)      PDF(pc) (4646KB)(2189)       Save

Using monthly products from the International Comprehensive Ocean-Atmosphere Data Set (ICOADS), the International Satellite Cloud Climatology Project (ISCCP), and the Optimum Interpolation Sea Surface Temperature (OISST), the authors investigate the interannual variation of sea-surface temperature (SST) along a meridional transection in the South China Sea (SCS). It is found that the air-sea interaction in the tropical Pacific plays an important role in the SCS SST variation. Taking warming as an example, the SCS SST warms up in the winter of El Nino developing year and again in the following summer. The first SCS warming occurs during the mature phase of El Nino. The decrease in cloudage and increase in net shortwave radiation flux contribute to the SST warming in the winter. The air-sea interaction associated with El Nino has a direct impact on this SCS warming process. The second warming occurs in the summer after the decay of El Nino. The weakening summer monsoon reduces the latent heat flux release and coastal upwelling off the southeastern Vietnam, which could not be attributed to the direct impact of the El Nino.

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Cited: CSCD(11)
Preliminary study on formation process of Sansha Yongle Blue Hole
GAO Jinwei, FU Tengfei, ZHAO Minghui, ZHANG Hanyu, TIAN Liyan
Journal of Tropical Oceanography    2022, 41 (1): 171-183.   DOI: 10.11978/2021077
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Blue holes retain original water, sediments, fossil remains, and intact organic skeletons, which are important natural heritages and geologic miracles and have great scientific values. As the deepest blue hole discovered in the world, the Sansha Yongle Blue Hole (SYBH) has typical cavity structure and hydrochemistrical characteristics; however, its formation process is still a scientific puzzle. Based on the tectonic evolution of the South China Sea, we analyze the development history of carbonate platform in Yongle Atoll. Formation of Yongle Atoll is mainly attributed to the aggradation and backstepping of carbonate platform that could generate escarpment to erosional platform margins and facilitate development of faults/fractures along the banks. According to oxygen isotopes (δ18O) in carbonate cores from the drilled wells of Yongle Atoll, phreatic dissolution mainly occurred from 14.75 m to 168.60 m in depth, which agrees with collapse of deep voids observed above the cave break at the depth 158m in Yongle Atoll. Compared with other blue holes and caves in the world, we propose that the formation of the SYBH is due to a combined action of fault/fracture of bank margin and collapse of deep voids. Phreatic (fresh water and sea water) dissolution along the fault/fracture formed sub-vertical sinkhole above 158 m in depth through collapse of deep voids, whereas it continued to work along fault/fracture to form a slightly inclined and narrower cave downward below 158m. Then, the SYBH finally evolved into a deep blue hole due to flooding of rising sea level. This study provides important knowledge and reference for exploring other blue holes in the future.

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Internal-wave characteristics of strong bottom currents at the sand-wave zone of the northern South China Sea and its role in sand-wave motion
XIA Hua-yong,LIU Yu-qiang,YANG Yang
Journal of Tropical Oceanography    2009, 28 (6): 15-22.   DOI: 10.11978/j.issn.1009-5470.2009.06.015
Abstract2337)      PDF(pc) (2386KB)(1835)       Save

From the 6th March to the 9th April in 2008, serial bottom-current observations were carried out at the sand-wave zone of the continental shelf and slope in the northern South China Sea (SCS). The measurements show that the tidal current and ocean current are weak at the observation sites, but bottom currents as strong as 30-77 cm.s-1 occur frequently. The directions of the strong bottom currents are related to the northwestward propagation of the internal waves in the region. Most of the strong currents are nearly northwestward or nearly southeastward, and the southeastward currents are stronger than the northwestward ones, which corresponds to the feature of downslope flows stronger than upslope ones when internal waves propagating onshore. Rotary power spectral analysis is carried out for the time series of current velocity. The results show that most of the rotary components higher than the frequency of M2 tide have the characteristics of internal-wave flows, further demonstrating that the frequent, strong bottom currents are induced by internal waves. The measurements are used to calculate the motion speed of sand waves. The results also show that the strong currents can initiate the sea bottom sediments, and due to downslope flows stronger than upslope ones, the sand waves move southeastwards at a low speed less than 1.6 m.yr-1. In addition, the authors model the coupled tide-storm bottom current fields in the northern SCS. From the modeling, the bottom currents, driven by strong typhoon and tide, can move the sand waves, but only move them a very short distance during each typhoon process. The direction of the movement is subject to the typhoon route, which is not always southeastward. Therefore, the coupled tide-storm currents are not the major factor to move the sand waves.

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Cited: Baidu(22) CSCD(9)
Simulations of the northern South China Sea using WAVEWATCH Ⅲ and SWAN
JIANG Li-fang,ZHANG Zhi-xu,QI Yi-quan,CHEN Rong-yu
Journal of Tropical Oceanography    2011, 30 (5): 27-37.   DOI: 10.11978/j.issn.1009-5470.2011.05.027
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We study the applicability of the National Centers Environmental Prediction/University Corporation for Atmospheric Research ( NCEP/NCAR) reanalysis wind field using the buoy data including the wind speed, significant wave height and mean wave period from September 1987 to August 1988 in the northern South China Sea (SCS). To some extent, the NCEP/NCAR reanalysis wind speed is consistent with the buoy data in the northern SCS. Then we assess the simulations using wave models WAVEWATCH Ⅲ (WW3) and Simulating Waves Nearshore (SWAN) forced by the NCEP/NCAR reanalysis data. The results show that the simulations of the significant wave height (SWH) from the two models are almost the same during the monsoon and monsoon transition periods. The simulation of the mean wave period (MWP) from the WW3 is better than that from the SWAN during the monsoon period, while the results are just contrary during the monsoon transition period. The spatial characteristics from the WW3 simulation in the northern SCS are presented. The SWH affected by monsoon shows significant seasonal change in the northern SCS, while the MWP presents certain semi-annual variability.
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Cited: Baidu(11) CSCD(10)
Effects of NaHSO3 on the growth and contents of photosynthetic pigments in Dunaliella salina
CHENG Jian-feng,HU Fen-hong,SHEN Yun-gang
Journal of Tropical Oceanography    2010, 29 (3): 65-70.   DOI: 10.11978/j.issn.1009-5470.2010.03.065
Abstract2301)      PDF(pc) (326KB)(4071)       Save

Bisulfite (NaHSO3) is a substance to accelerate plant cyclic photophosphorylation that can be used safely and environmentally friendly. In order to optimize the nutrients formula, decrease the production cost and improve the biomass and pigment accumulation of Dunaliella salina, the authors investigated the effects of different concentrations (0.00?0.40mM•L-1) of NaHSO3 on the biomass and photosynthetic pigment contents. The results showed that NaHSO3 could significantly improve the growth, contents of chlorophyll (Chl) a, Chl b, Chl (a+b), carotenoid (Car) and ratio of Chl to Car. The effects firstly increased and then decreased with the increase of concentration. Accelerating effects under low concentrations (<0.10mM•L-1) were better than those under high concentrations (0.10?0.40mM•L-1), and the maximum accelerating effects were reaches at 0.07mM•L-1. NaHSO3 could increase Chl b content more than Chl a content, which caused the reduction of Chl a content relative to Chl b content; the effects firstly decreased and then increased with the increase of concentration, reducing effects under low concentrations (<0.1mM•L-1) were better than those under high concentrations (0.10?0.40mM•L-1), and the minimum reducing effect was achieved at 0.07mM•L-1. The correlations of biomass (Y) to contents of photosynthetic pigments and between contents of photosynthetic pigments were significant or markedly significant, with the highest correlation of Chl b (XChl.b) to biomass (Y=0.284XChl.b-0.883 (R2=0.994**)) and the next of Chl to biomass (Y=0.100XChl-2.022 (R2=0.993**)), which provided an indirect index to measure the growth of Dunaliella salina in every moment.

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An ecological study on fouling in the waters off the Bailong Peninsula in the Beibu Gulf
LI Heng-xiang,YAN Yan,HE Wei-hong,ZOU Xiao-li
Journal of Tropical Oceanography    2010, 29 (3): 108-113.   DOI: 10.11978/j.issn.1009-5470.2010.03.108
Abstract2290)      PDF(pc) (288KB)(4602)       Save

An annual panel test on fouling organisms was carried out in the waters off the Bailong Peninsula in the Beibu Gulf from March 2006 to February 2007. The fouling organisms from the wharf and the cultured cages during the same time were also investigated. The biofouling in this area reflected distinct characteristics of subtropical harbors. A total of 82 fouling organism species were recorded, among which Balanus reticulates, Dexiosprira foraminosus, Spirorbis papillatus, Bugula neritina, Membranipora grandicella, Styela canopus, Electra tenella, Perna viridis and Dendostrea crenulifera were dominant species. Bioattachment occurred throughout the year, but the main period of settlement extended from May to October of 2006. The mean biomass of fouling organisms on the monthly, seasonal, and annual test panels were 200.54, 2 550.37 and        15 121.67g•m?2, respectively, in the waters off the Bailong Peninsula, which were lower than those in the waters of the Daya Bay and Zhanjiang Harbor, but higher than those in the waters of the Qinglan Harbor and off the Weizhou Island. The attachments of fouling were greatly different in each tidal zone of the Bailong Wharf, with the dominant species Littorina scabra and Nodilittorina radiate on high tidal zone, Ostrea glomerata, Saccostrea echinata, Saccostrea cucullata and Tetreclita squamosa on middle tidal zone, and algae on low tidal zone. Different suggestions on biocontrol are given in the present study for protecting the artificial structures, mariculture, and estuarine ecology in the Bailong waters.

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Cited: Baidu(12) CSCD(9)
Response of mangrove swamp sedimentation rate to climate change
Tao LIU, Ying LIU, Yuanfu YUE
Journal of Tropical Oceanography    2017, 36 (2): 40-47.   DOI: 10.11978/2016052
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Mangrove swamp plays an important role in the maintenance of ecological balance in tropical-subtropical coastal regions, as well as in the global carbon cycle. The grain size characteristic and sedimentary rate of two mangrove swamps were studied. The grain size and proportion of storm deposit were determined, and the factors that influenced storm sediment inputting flux were analyzed. The variation of mangrove swamp accretion rate in response to climate change was also studied. The main conclusions are as follows. 1) The inputted sediments were silt and clay in normal weather condition during tidal process, while the sand component in mangrove swamp sediment was likely inputted by storms. In mangrove swamp sediment, the proportion of storm deposit was 56% for mangrove swamp of the Nanliujiang River estuary and 73% for Daguansha mangrove swamp. 2) The sedimentation rate of mangrove swamp was positive related to typhoon landfall frequency rather than rain fall. 3) The storm energy was higher in Daguansha mangrove swamp than in the Nanliujiang River estuary, likely attributing to its open coastline shape with narrow width in tidal zone and mangrove belt, which may deduce more storm deposit inputted and higher sedimentary rate.

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Evaluation of heavy-metal pollution in Shenzhen coastal sediments
DAI Ji-cui,GAO Xiao-wei,NI Jin-ren,YIN Kui-hao
Journal of Tropical Oceanography    2010, 29 (1): 85-90.   DOI: 10.11978/j.issn.1009-5470.2010.01.085
Abstract2269)      PDF(pc) (326KB)(2375)       Save

Based on the field data of Shenzhen coastal surface sediments from 2000–2007, methods of geo-accumulation index and potential ecological risk index are employed to evaluate heavy-metal pollution status in the area. Results show that Shenzhen coastal sediments have been polluted by heavy metals. The quality degree of most coastal sediments are Class II except for the Gushu Coast. The severity of heavy-metal pollution is: the Gushu Coast, the middle of the Shenzhen Bay, the mouth of the Shenzhen Bay, followed by the mouth of the Shatoujiao Bay that is least polluted. Among heavy metals found in the sediments, Cu and Zn are the two most seriously-polluting elements. The average contents of Cu and Zn in Gushu coastal sediments are 128.96mg·kg−1 and 199.40mg·kg−1, belonging to Class III; other coastal areas of Shenzhen belong to Class II. The results also reveal that there are no potential ecological risks for Shenzhen coastal sediments. The order of potential ecological risks is, Hg>Cd>Cu>As>Pb>Cr>Zn.

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Cited: Baidu(14) CSCD(9)
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Journal of Tropical Oceanography    2009, 28 (3): 45-53.   DOI: 10.11978/j.issn.1009-5470.2009.03.045
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Cited: CSCD(6)
Relationship between ENSO events and regional climate anomalies around the Xisha Islands during the last 50 years
YAN Hong,SUN Li-guang,LIU Xiao-dong,QIU Shi-can
Journal of Tropical Oceanography    2010, 29 (5): 29-35.   DOI: 10.11978/j.issn.1009-5470.2010.05.029
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The authors investigate the relationship between ENSO events and regional climate anomalies around the Xisha Islands during the last 50 years. They find that there is evident correlation between ENSO events and the regional climate anomalies. There is a significant positive correlation between air-temperature anomalies and ENSO index (MEI). Power spec-tral analysis shows that the temperature anomalies have similar cycles to the ENSO index. Regarding to rainfall, the annual precipitation in La Niña years is much more than that in El Niño years. As to tropical cyclone, its frequency during El Niño is significantly lower than that during La Niña.

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Cited: Baidu(35) CSCD(10)
Sea spray parameterization used in typhoon simulations
LIU Lei,ZHENG Jing,LU Zhi-wu,ZHANG Yi-tao
Journal of Tropical Oceanography    2010, 29 (3): 17-27.   DOI: 10.11978/j.issn.1009-5470.2010.03.017
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Sea spray, an important factor in the air-sea interaction, plays an essential role in the occurrence and evolution of typhoon. In order to examine the impact of different sea spray parameterizations on typhoon simulations, the Fairall and Andreas schemes were included in the WRF atmosphere model to simulate two typhoons. The results show that the latent and sensible heat fluxes increased greatly in the Fairall scheme. Since the heat construction of the typhoons changed and the warm core was obvious, the dynamic construction changed as well. Relative diff-vortex explains the cause of the change in typhoon's track and the diff-divergence, vortex and the vapor flux affect the intensity of typhoon. The Andreas scheme, which considers the change of roughness in momentum, heat, and moisture with wind speed and relative humidity, has lower latent and sensible heat fluxes than the Fairall scheme, so the intensity of the typhoons is strong. The simulation of track is less impacted by different sea spray parameterizations.

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Cited: Baidu(7) CSCD(6)
Tidal energy fluxes and dissipation in the South China Sea without considering tide-generated potential energy
TONG Jing-quan,LEI Fang-hui,MAO Qing-wen,QI Yi-quan
Journal of Tropical Oceanography    2010, 29 (3): 1-9.   DOI: 10.11978/j.issn.1009-5470.2010.03.001
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The tidal energy fluxes and dissipation of the principal barotropic tidal constituents M2, S2, K1 and O1 over the South China Sea (SCS) are examined in detail using the simulated tidal results of the Estuarine, Coastal and Ocean Model(ECOM). The results show that the M2, S2, K1 and O1 tidal energy fluxes across the Luzon Strait from the west Pacific are 38.93, 5.77, 29.73 and 28.97 GW into the SCS respectively, and the corresponding fluxes across the Karimata Strait into the Java Sea are 2.42, 0.36, 8.67 and 7.86 GW, respectively. There are also M2 tidal energy fluxes of 25.28 GW into the Taiwan Strait from the East China Sea and northwest of the Luzon Strait. The semi-diurnal tidal energy fluxes into the Beibu Gulf of and the Gulf of Thailand (6.52 GW in all) are much weaker than the diurnal tides (24.74GW). There is 12.28GW of diurnal tidal energy flux into the Sulu Sea from the SCS, while 1.92 GW of semi-diurnal tidal energy flux in a contrary direction. The net tidal energy fluxes and bottom boundary layer dissipation, which should be equal to each other in steady state, are not balanced in each area of the SCS. The most convenient management to this is to modulate the bottom friction coefficients, which are calculated to be 0.0023, 0.0024, 0.0023, and 0.0021 for the Taiwan Strait, the Beibu Gulf, the Gulf of Thailand and deep sea areas in the SCS, respectively.

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Cited: Baidu(3) CSCD(5)
Erosion-deposition analysis of underwater slope on lagoon and sand barriers in the Swan Lake, Rongcheng, Shandong province
YU Jiankui, REN Zonghai, ZHAN Chao, ZHANG Yuchen, GENG Wenqian, WANG Qing
Journal of Tropical Oceanography    2022, 41 (4): 61-70.   DOI: 10.11978/2021141
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The Swan Lake in Rongcheng of Shandong province is a typical lagoon-barriers system. Since 1980s, under the influence of human activities, the environmental system of the Swan Lake has changed with strong erosion of the sand dam. Studying the erosion and deposition of underwater bank slopes is of great significance for understanding the evolution of lagoon-sand dam system and protecting the environment of Swan Lake. This paper focus on the underwater bank slope of the sand dam at the east side of the Swan Lake. Based on the combination of chart data from 1960 to 2014 and geographic information technology, we have obtained multi-year water depth of the coastal waters on the east side of the Swan Lake since 1960, and analyzed the contour changes, scouring and silting changes and topographic changes of the set profile in the sand dam area on the east side of Swan Lake. The results show that the overall depth contours moved towards the sea from 1960 to 1980, while the tendency of contours moving towards the sea from 1980 to 2014 slowed down, the 0 m depth contour at the entrance of the tidal channel retreated 126.70 m to the shore from 1960 to 2014. The underwater bank slope of the Swan Lake was at a state of siltation from 1960 to 1980, the annual siltation rate is 3.60 cm·a-1. The erosion area increased significantly from 1980 to 2014, and the erosion and siltation phases were distributed, the annual siltation rate is 0.79 cm·a-1. The underwater bank slope of the Swan Lake sand dam is steep and gentle, and the north side of the tidal channel entrance is more likely to be eroded than the south side. Human activities have changed the environmental state of the Swan Lake, leading to partial erosion and retreat of the underwater bank slope of the Swan Lake.

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A numerical study on hypoxia and primary production in the Pearl River Estuary in summer using the modified RCA water quality model
ZHANG Heng,LI Shi-yu
Journal of Tropical Oceanography    2010, 29 (1): 20-31.   DOI: 10.11978/j.issn.1009-5470.2010.01.020
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The RCA water quality model was incorporated with the sediment module and the light shading effect due to the high turbidity in the Pearl River Estuary (PRE). The modified RCA water quality model was then applied to the PRE. Results show that the modified RCA model can reproduce the distribution of nutrients, phytoplankton and dissolved oxygen (DO) in the PRE successfully, which means the modified model can capture the main processes of water quality in the PRE. In the wet season, huge amount of fresh water enters the PRE and results in a river plume. Particulate organic matter (POM) deposits intensely in specific areas of western and central shoal of the Lingdingyang Estuary and outside Modaomen as a result of the plumes. Furthermore, high deposition rate of POM in specific areas leads to high sediment oxygen demand (SOD), which coincides with the areas with strong stratification. High SOD and strong stratification lead to hypoxia. On the shelf areas, primary production increases as the suspended sediment concentration decreases, but the increasing primary production does not result in hypoxia as the marine particulate organic carbon (POC) spreads all over the shelf and the stratification is weak.

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Cited: Baidu(4) CSCD(5)
The outbreak of Cochlodinium geminatum bloom in Zhuhai, Guangdong
OU Lin-jian,ZHANG Yu-yu,LI Yang,WANG Hua-jie,XIE Xue-dong,RONG Zhi-ming,LÜ Song-hui,QI Yu-zao,
Journal of Tropical Oceanography    2010, 29 (1): 57-61.   DOI: 10.11978/j.issn.1009-5470.2010.01.057
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Blooms of Cochlodinium polykrikoides occur frequently around the world. During October to November, 2006, an unusual bloom of Cochlodinium geminatum occurred in the coastal eutrophicated waters in Zhuhai, Guangdong. The water temperature and salinity in the bloom zone ranged between 23.41-27.54℃ and 15.49-17.92 psu, respectively. The density of C. geminatum increased significantly with water temperature and salinity and reached to the highest density of 1.6×106 ind.L-1. During the latter period of bloom, the decrease of water temperature and the increase of density of Mesodinium rubrum might be responsible for the dissipation of the C. geminatum bloom.

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Cited: Baidu(28) CSCD(9)
XIANG Rong,CHEN Mu-hong,CHENG Xin-rong, ZHANG Lan-lan, LU Jun,Liu Jian-guo,CHEN Zhong
Journal of Tropical Oceanography    2009, 28 (3): 59-66.   DOI: 10.11978/j.issn.1009-5470.2009.03.059
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The authors analyzed oxygen and carbon isotope of planktonic foraminifera from surface sediments and plankton tow samples collected from southern South China Sea (SCS) in spring 2002, and discussed their relationship with marine environmental parameters and depositional process. Their results show that Globigerinoides ruber and G. sacculifer have almost the same average δ18O values in the spring tow samples, which are obviously lighter than those in the surface sediments. In the surface sediments, however, the average δ18O value of G. ruber is apparently lighter than that of G. sacculifer, which may be related to gametogenesis calcification of G. sacculifer and seasonal difference of the two species. The average δ18O value of Pulleniatina obliquiloculata is apparently heavier than that of G. ruber and G. sacculifer in both the surface sediments and the upper water, suggesting a large intra-species δ18O gap between the three species. The average δ18O value of P. obliquiloculata in the upper water in spring is about 0.7‰ lighter than that in the surface sediments, possibly due to the winter flourish of P. obliquiloculata that prefers the low temperature of winter water. The average δ13C values of the three species show a similar trend in both the sediments and the upper water, namely, the heaviest for G. sacculifer, the lightest for P. obliquiloculata, and G. rubber in the middle. The difference of δ13C values between the three species may be mainly caused by vital effect. The regional variations of δ18O values of G. ruber and G. sacculifer in the surface sediments show a similar trend, with heavy values in the northwest and gradually lightening to the southeast of the studied area, all accords with the trend of yearly-averaged sea-surface temperature of gradually increasing from northwest to southeast. Both the δ18O and δ13C of P. obliquiloculata show heavier values in the upwelling stations of the studied area. The relationship of δ13C of P. obliquiloculata with nutrient level of the upper-water mass in southern SCS is contrary to that in northern SCS, which needs to be confirmed by future studies.
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Review of eco-development model for mangrove land-based enclosure aquaculture in the Pearl River Estuary
ZHANG Qiao-min,SHI Qi,YU Ke-fu
Journal of Tropical Oceanography    2010, 29 (1): 8-14.   DOI: 10.11978/j.issn.1009-5470.2010.01.008
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The traditional mangrove land-based enclosure aquaculture model originated in the Pearl River Delta is a good example showing how mangroves can be used sustainably. This paper introduces three examples of mangrove land-based enclosure aquaculture at the mouth of the Pearl River Estuary. The first example is about the only operating traditional mangrove land-based enclosure for shrimp farming located in Mai Po Marshes Nature Reserve of Hong Kong and managed by WWF Hong Kong; its history goes back to the mid-1940s and its focus for management strategy has evolved from being commercial culture ponds to performance of multi-ecological functions including feeding habitat for piscivorous water birds, bird-watching, environmental education, as well as shrimp farming. The second example is the mangrove land-based enclosure for traditionally extensive aquaculture trial in the Dawei Bay on the Qi’ao Island of Zhuhai City, regarding measurement and analyses of relationship between the environmental condition change of water level and salinity and the mangrove community dynamics inside land-based enclosure. The third example is the mangrove planting-aquaculture system trial in the Shenzhen Waterlands Resort on the east coast of the Lingdingyang Estuary, including research on water purification function by mangroves. For mangrove protection and management and for marine pollution prevention in the Pearl River Estuary waters, the following suggestions are given: 1) Preventing resolutely the development model of clearing mangrove for aquaculture ponds, and disseminating and applying the eco-development model of land-based enclosure aquaculture or mangrove-friendly aquaculture; 2) Building new land-based enclosure aquaculture demonstration site in major mangrove regions, and exploring mangrove-friendly restoration model in aquaculture pond areas built by clearing mangroves; 3) strengthening relevant scientific research for maximizing comprehensive efficiency of mangrove land-based enclosure aquaculture.

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Cited: Baidu(5) CSCD(1)
The characteristics and sources of surface sediments in the Pearl River Estuary and its adjacent shelves
ZHANG Ling,CHEN Fan-rong,YIN Ke-dong,LÜ Ying,YANG Yong-qiang,ZHANG De-rong
Journal of Tropical Oceanography    2010, 29 (1): 98-103.   DOI: 10.11978/j.issn.1009-5470.2010.01.098
Abstract2143)      PDF(pc) (391KB)(2266)       Save

The authors study the characteristics and sources of organic carbon, nitrogen and the hydrolysable amino acids (THAA), total carbohydrates (TCHO), total lipid and acid-insoluble organic compounds (AIOC) in the surface sediments of the Pearl River Estuary (PRE) and its adjacent shelves. The results show that the organic matter in the PRE was mainly derived from mixed sources of terrestrial and aquatic origins, whereas the organic matter in the adjacent shelves was predominantly algal-derived. Terrestrial higher plants were rich in more lignin and cellulose, which were exported to the PRE. As a result, the content of TCHO in the sediment of the estuary was higher than that in the adjacent shelves, while the content of aquatic organic matter in the estuary was close to that in the adjacent shelves. The proportions of THAA and TCHO were 56%, 48% and 19% in plankton, suspended particulate and surface sediment, respectively; suggesting that the organic matter had undergone degradation during the sedimentation to the water-sediment interface.

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Cited: Baidu(21) CSCD(11)
ZHAO Huan-Ting
Journal of Tropical Oceanography    2009, 28 (3): 5-15.   DOI: 10.11978/j.issn.1009-5470.2009.03.005
Abstract2130)      PDF(pc) (2599KB)(2150)       Save
The Chinese probably first had the name of the South China Sea (pronounced as “Nanhai” in Chinese, where “Nan” means “south”, “hai” means “sea”) in writing at the time of Wuwang Period (1046 BC-1043 BC) during the Zhou Dynasty. “Nanhai (place name)”, was named for its closeness to the South China Sea (Nanhai), which clearly suggests that the term “Nanhai (place name)” was used later than the term “Nanhai (sea name)”. During Chengwang Period (1042 BC-1021 BC) of the Zhou Dynasty, the famous tribute of black millet (Indian millet), known as the story of “Millet of Nanhai”, was from the “Nanhai (place name)”. In Xuanwang Period (827 BC -782 BC) of the Zhou Dynasty, the name “Nanhai” used in the poem Jiang Han includes both the “Nanhai (sea name)” and “Nanhai (place name)”, which was the first time the name was used in writing. “Nanhai” was then used in Yu Gong of Shang Shu in late Zhanguo Period (475 BC -221 BC), but whether it meant the “Nanhai (sea name)” or not has yet to be confirmed. “Nanhai” was later used in Hai Nei Dong Jing of Shan Hai Jing during the Qin (221 BC -207 BC) and Han (206 BC- AD 220) Dynasties; it was also used in Nan Yue Lie Zhuan of Shi Ji and in an ancient map of early Western Han Dynasty (206 BC- AD 8), where it was definitely referring to the “Nanhai (sea name)”, just like its present meaning. From the Eastern Han Dynasty (AD 8-220) to the Tang (AD 618-907) and Song (AD 960-1279) Dynasties, the “Nanhai” was referred as the “Zhanghai”. Over the Ming (AD 1368-1644) and Qing (AD 1644-1911) Dynasties, the “Nanhai” was called the “Daminghai” and “Daqinghai” by foreigners. Then the “Nanhai” was translated as the “South China Sea” by foreigners and the name “South China Sea” has been widely used all over the world. Unfortunately, some Chinese translate the English name “South China Sea” directly into Chinese as the “Nanzhongguohai”, which is then used by some books, magazines and media. The “Nanhai” was first found and named by Chinese around 3 000 years ago, which has been well recognized all over the world. The “Nanhai” is the only name used in official publications and maps by the most recent governments of China. The “Nanhai” is also the only name used in the related administrative departments, armed forces and institutions. Therefore, the “Nanhai” should not be called the “Nanzhongguohai”. People using the name “Nanzhongguohai” can be considered ignorant to Chinese history, which may mislead people to think that the “Nanhai” (South China Sea) was first found and named by foreigners, and further confuse the Chinese sovereignty on the Nanhai.
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Cited: CSCD(2)
Discussion on grain-size grading scale and sediment classification for marine sand and gravel
NI Yugen, LI Jianguo, XI Long
Journal of Tropical Oceanography    2021, 40 (3): 143-151.   DOI: 10.11978/2020062
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In recent years, the demand for marine sand and gravel increased sharply. Accordingly, its exploration and exploitation developed rapidly. To avoid naming confusion in the field of marine sand and gravel investigation and research, we analyzed the characteristics of the existing grading scales and sediment classification schemes based on years of marine sand and gravel investigation experience and previous research results, and put forward a set of grading scale and sediment naming method suitable for marine sand and gravel. Based on the Udden-Wentworth geometric series grading scale (phi scale), we proposed a particle size grading scale for marine sand- and gravel-related sediments, which divides the particle size grades into three categories of gravel (>2 mm), sand (2~0.063 mm) and mud (<0.063 mm), and nine subcategories. Based on preponderant grain-size composition, we proposed a “gravel-sand-mud triangular diagram + detailed naming of sandy and gravelly sediment” classification scheme, which embodies the idea of “detailed naming of sandy and gravelly sediments while simplifying naming of muddy sediments.” This can directly reflect the grain-size composition and content of marine sand and gravel.

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Development of international marine observation system and construction of deep-sea station in China
LI Jian ,CHEN Rong-yu,WANG Sheng-an,MAO Hua-bin,HE Yun-kai,SUI Dan-dan,XIE Qiang,SHI Ping,YANG Yue-zhong,WANG Dong-xiao
Journal of Tropical Oceanography    2012, 31 (2): 123-133.   DOI: 10.11978/j.issn.1009-5470.2012.02.017
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Since the 1980s, marine observation has become much more diversified, capable of delivering three-dimensional and real-time data. National and regional observing systems have been playing important roles in key regions of the oceans. Going with the development of technology and concept innovation, regional marine observation system has been widely used and gradually improved. International marine observation stations, such as the Irish Sea Coastal Observatory, the Carolinas Regional Coastal Ocean Observing System (RCOOS), and the Victoria Experimental Network Under the Sea (VENUS) are great examples, which consist of three-dimensional and real-time data, combined with marine ecosystem, physical, biological and chemical models. Some other examples, such as the American “ North-East Pacific Time-series Undersea Networked Experiments ” (NEPTUNE), the “ European Seafloor Observatory Network ” (ESONET) and the Japanese “ Advanced Real-time Earth monitoring Network in the Area ” (ARENA) are deep-sea network systems, which make th e ocean observatory more comprehensive. Under these international backgrounds, the first deep-sea observation research network station in China-Xisha Marine Research Station was completed in 2008 and has started offering real-time data. The observation system mainly includes automatic weather station, mooring in the western boundary, biological traps, Xisha surface ocean observation system, and Xisha Ocean Optics observation system. Because of the complexity of marine structure, harsh working environment and resource shortages, marine observation could be a high risk task. With the knowledge of the domestic and international marine observation systems reviewed in this study, it is hoped that Chinese marine observation system could be developed and improved to achieve more rapid progress.
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Cited: Baidu(8) CSCD(8)
Analysis and evaluation of nutrition composition of double-headed parrotfish Cheilinus undulates
OU You-jun,LI Jia-er
Journal of Tropical Oceanography    2010, 29 (3): 97-102.   DOI: 10.11978/j.issn.1009-5470.2010.03.097
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Nutritive composition in muscle of wild double-headed parrotfish Cheilinus undulates was investigated in this study. Results showed that the contents of moisture, crude protein, crude lipid, and crude ash in fresh muscle of C. undulates were 80.97%, 18.38%, 0.10% and 0.49%, respectively. A total of 18 kinds of common amino acid in the muscle was detected with the 15.7%(wet weight); the content of essential amino acids was 39.37% of the total ones, which met the Food and Agriculture Organization of the Untied Nations/World Health Organization (FAO/WHO) standard. The ratio of branch-chain amino acids to aromatic amino acids was 2.5654, close to the normal value of that in human. According to nutritive evaluation in amino acid score(AAS), the first limited amino acid was threonine (Thr), the second was tryptophane (Trp), and the value of essential amino acid index (EAAI) was 68.46. The total content of four smelled amino acids was 31.85%. The content of EPA + DHA in fatty acids was 21.86%。The elements of Na, K, Ca, Mg, Fe, Cu, Zn were found in muscle, which were essential for the human. In conclusion, this research indicated that C. undulates is a nutritive sea-food fish.

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Cited: Baidu(11) CSCD(9)
Numerical Models of the Tectono-Thermal Evolution of Rift Basins and Their Applications to the Northern South China Sea
LIAO Jie,ZHOU Di,ZHAO ZHONGXIAN,
Journal of Tropical Oceanography    2009, 28 (6): 41-51.   DOI: 10.11978/j.issn.1009-5470.2009.06.041
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Numerical models are the basis for quantitative modeling of the tectono-thermal evolution of sedimentary basins. Due to the importance of rift basins in scientific research and petroleum exploration, extensive studies have been devoted to building numerical models for rift basins. This paper summarizes the models that have great influence or play an important role in the study of the passive continental margin of the South China Sea, including the most fundamental model of McKenzie, and the models of finite-rate stretching, simple shear stretching, flexural cantilever stretching, depth-dependent stretching, and multiphase stretching. Special emphasis was placed on their basic assumptions, application conditions, and numerical formulations for the geothermal field and basin subsidence. The similarities, differences, and correlations of these models were expounded. Finally, the applications of the models in studying the rift basins in the northern South China Sea were briefed, which may help to advance our understanding of the methods and applications of the numerical models.

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Cited: CSCD(2)
Effects of N to P ratio on the growth of two red tide diatom Skeletonema costatum and Thalassiosira weissflogii
LIU Hao,Gao Yong-li,YIN Ke-dong,YUAN Xiang-cheng,XU Jie,HARRISON Pau
Journal of Tropical Oceanography    2010, 29 (6): 92-97.   DOI: 10.11978/j.issn.1009-5470.2010.06.092
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The growth character and ecophysiology of Skeletonema costatum and Thalassiosira weissflogii were studied in culture medium of different ambient ratios of N to P (4︰1, 16︰1, 64︰1). Bacth cultures of these two phytoplankton species were conducted to examine their growth rates, Chl-a, DIN︰P (dissolved inorganic nitrogen and phosphorus) and PON︰P (particular organic nitrogen and phosphorus) during incubation periods. The results showed that the N︰P ratio could signifi-cantly influence the growth of Skeletonema costatum and Thalassiosira weissflogii. The ratio of N to P could evidently influ-ence these two diatom species. The growth rate, cell numbers and Chl-a of these two species were obviously lower with N-limitation (N︰P=4︰1) than those with P-limitation (N︰P=64︰1). The results suggested that T. weissflogii was more sensitive to N-limitation than S. costatum. Although cultured in different N︰P ratios medium, the N︰P composition of these two algal species hardly changed with the medium N︰P ratio. Due to the luxury consumption, the cells could still take up excessive nutrients for living when other nutrients were depleted by phytoplankton, which resulted in different N︰P ratios of phytoplankton. N-limited medium reduced the N︰P ratio of the algal cells, while P-limited medium increased the N︰P ratio of the phytoplankton cells significantly.

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Cited: Baidu(16) CSCD(18)
Influence of Nitrogen and Phosphorus on Phytoplankton Community Structure in Dapeng’ao Bay, Daya Bay
II Species Composition
ZHU Ai-jia,HUANG Liang-min,LIN Qiu-yan,XU Zhan-zhou,
Journal of Tropical Oceanography    2009, 28 (6): 103-111.   DOI: 10.11978/j.issn.1009-5470.2009.06.103
Abstract2098)      PDF(pc) (3236KB)(1712)       Save

In situ survey in the surface of Dapeng’ao Bay (Daya Bay), combined with nutrient enrichment bioassays were conducted in April-May (spring), August (summer) and November (autumn), 2005 in order to better understand the potential influence of nitrogen (NO3- or urea) and phosphate(PO43-)on the species composition of phytoplankton in this area in different seasons. In spring, the abundance of phytoplankton in Dapeng’ao Bay was the highest but the diversity index was the lowest among the three seasons. The dominant species had significant seasonal variations. The horizontal variation of species composition was more significant in autumn than that in any other season. Results showed that the succession among the dominant species Rhizosolenia alata f. genuina, Leptocylindrus danicus and Chaetoceros cinctus from spring to summer may due to the change of the condition of nitrogen (N) and PO43-. In summer, there should be factors other than nitrogen or PO43- controlling the succession between the dominant species Thalassionema nitzschioides and Thalassiosira weissflogii. Although phosphorus is consider to be the most limiting factor for the growth of phytoplankton in this area, the treatment with high N:P ratio in summer did not showed any phosphorus (P) limiting effect, and the variation of N:P ratio had little effect on the species composition. Further more, the potential impact of nitrogen on the species composition was more significant than PO43- in autumn.

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Seasonal variability of salinity budget in the southeastern Arabian Sea
ZHANG Yu-hong,XU Hai-ming,DU Yan,WANG Dong-xiao
Journal of Tropical Oceanography    2009, 28 (5): 66-74.   DOI: 10.11978/j.issn.1009-5470.2009.05.066
Abstract2092)      PDF(pc) (5210KB)(1957)       Save

Based on the monthly mean data of Simple Ocean Data Assimilation (SODA) product, the authors analyze the seasonal salinity budget of surface layer in the southeastern Arabian Sea., The salinity variation in the region cannot be explained by surface freshwater flux. The salinity budgets in two typical regions show that horizontal advection dominates salinity variation, decreasing the salinity in winter and increasing it in summer, except for the coastal region off western India where the surface freshwater flux decreases salinity in summer. During winter, the northeast monsoon current advects fresher water from the Bay of Bengal into the Arabian Sea along the same latitude and then transports the low saline-water northward, resulting in salinity reduction in the surface layer of the southeastern Arabian Sea. During summer, southwest monsoon current advects high-salinity water in the northwestern Arabian Sea southeastward, increasing the salinity in the surface layer of the southeastern Arabian Sea. In the southeastern Arabian Sea, salinity variation of the surface layer is prominently stronger in winter than in summer.

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Cited: Baidu(11) CSCD(10)
Effect of heating rate on the upper incipient lethal temperature for copepods
JIANG Zhi-bing,ZENG Jiang-ning,CHEN Quan-zhen,LIAO Yi-bo,GAO Ai-ge
Journal of Tropical Oceanography    2010, 29 (3): 87-92.   DOI: 10.11978/j.issn.1009-5470.2010.03.087
Abstract2087)      PDF(pc) (347KB)(3556)       Save

To explore how heating rate influences the thermal tolerance of copepods and to recommend heating rate criteria during copepod upper incipient lethal temperature (UILT) tests, four copepod species (Calanus sinicus, Labidocera euchaeta, Euchaeta concinna, Centropages dorsispinatus) collected from the Yueqing Bay were studied in laboratory under different heat-ing rates (1℃•h-1, 0.1℃•min-1, 1℃•min-1, and abrupt exposure). The results showed that thermal tolerance of the same copepod species varied with heating rate, and all the experimental copepods decreased in number from a heating rate of 0.1℃•min-1 to-wards quicker or slower heating rates. Thus, the rate of 0.1℃•min-1 was considered as the standard heating rate for UILT experi-ments. In the trial conducted at 0.1℃•min-1, the 24h-UILT of L. euchaeta, C. dorsispinatus, E. concinna and C. sinicus were 31.0℃, 29.6℃, 29.1℃ and 27.7℃, respectively; the 48h-UILT of L. euchaeta, C. dorsispinatus, E. concinna and C. sinicus were 30.1℃, 29.5℃, 28.6℃ and 27.3℃, respectively. Differences of thermal sensitivity between these animals were all significant.

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Cited: Baidu(6) CSCD(3)
Effects of salinity and nutrition on growth, respiration and excretion of Litopenaeus vannamei
SHEN Yu-chun,CHEN Zuo-zhou,WU Zao-he,HUANG Xiang-hu
Journal of Tropical Oceanography    2010, 29 (5): 111-118.   DOI: 10.11978/j.issn.1009-5470.2010.05.111
Abstract2083)      PDF(pc) (340KB)(2387)       Save

An experiment was conducted to determine the effects of salinity and dietary protein levels on growth, respiration and excretion of Litopenaeus vannamei. The composition of body muscle was analyzed. The results showed that the growth rate was increased with the increase of dietary protein level, but the survival rate was not significantly affected (P>0.05). The survival rate was not significantly increased with the increase of salinity in the different dietary protein levels (P>0.05). The growth rate was increased with the increase of salinity in a low salinity levels, the highest growth rate was obtained at 18, then it was decreased with further increase of salinity. The analysis of body composition showed that the crude protein, crude fat and ash content significantly increased with the increase of salinity (P<0.05), but moisture and nitrogen-free extract content decreased significantly (P<0.05). Crude protein and ash content significantly increased with the increase of dietary protein level (P<0.05), but moisture and nitrogen-free extract content decreased significantly (P<0.05), crude fat was not significantly affected (P>0.05).The oxygen consumption rate and the ammonia excretion rate were affected significantly by the different salinity and dietary protein levels (P<0.05). The oxygen consumption rate was significantly decreased with the increase of salinity and dietary protein level (P<0.05), appearance time of the high peak was 2−3 h after ingestion. The ammonia excretion rate increased with the increase of dietary protein level, but decreased with the increase of salinity, appearance time of the high peak was 2 h after ingestion. The oxygen-nitrogen ratio was affected significantly by the different salinity and the dietary pro-tein levels (P<0.05).

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Cited: Baidu(5) CSCD(4)
Surface salinity distribution of the Kuroshio in the East China Sea and its influencing factors
REN Hui-ru,KANG Jian-cheng,LI Wei-jiang,AN Yan,ZHANG Jian-ping,WANG Tian-tian
Journal of Tropical Oceanography    2011, 30 (5): 55-61.   DOI: 10.11978/j.issn.1009-5470.2011.05.055
Abstract2080)      PDF(pc) (690KB)(2339)       Save
Using the World Ocean Atlas 2005 by the National Oceanic and Atmospheric (NOAA) published in 2007, topography database in 2006 by the National Geophysical Data Center (NGDC), and the grid precipitation data of the Asian region by the Japan Agency for Marine-Earth Science and Technology ( JAMSTEC) published in 2003, the authors explore three-dimensional techniques for oceanic data analysis and figures manifestation with Matlab computer programs. They find that the surface salinity distribution of the Kuroshio in the East China Sea (ECS) varies monthly. First, the salinity at surface is higher in December through March, and is lower in June to September; the salinity in the rest of year is in between. Second, the salinity is the highest near the east side of the Kuroshio in the East China Sea where is closer to Ryukyu Island . The salinity at surface is affected by surface temperature, rain, and Changjiang diluted water. The salinity at surface of the Kuroshio in the East China Sea is mainly influenced by surface temperature near the shelf of contentious in November to February. Surface salinity is impacted by precipitation at small-scale in January and summer, which is in areas south of 25癗 and also near 30癗 where the ECS-Kuroshio flows into the Tokara Strait. Summer runoff of Changjiang diluted water affects most to the surface salinity of the Kushiro in a fan-shaped zone, resulting the maximum runoff in July and the corresponding minimum salinity on surface of the Kuroshio in the fan-shaped zone in the East China Sea .
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Cited: Baidu(11)
The distribution, enrichment and pollution assessment of heavy metals in surface sediments of sea areas around the Nanao Island
QIAO Yong-min,GU Ji-guang,YANG-Yang,HUANG Chang-jiang
Journal of Tropical Oceanography    2010, 29 (1): 77-84.   DOI: 10.11978/j.issn.1009-5470.2010.01.077
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The Nanao Island is the main island of the Nanao County, Guangdong province, and the sea area around the island is important for local social and economic development. A survey of heavy metal content, distribution, enrichment and pollution state in sediments was conducted in May and July 2004. A total of eleven sediment samples were collected from mariculture base: Houjiang Bay, Baisha Bay and A tourist resort: Qingao Bay along the coast of the Nanao Island. The results showed that the contents of heavy metals were Cd: 0.19mg.kg-1, Cr: 26.86mg.kg-1, Cu: 20.71mg.kg-1, Ni: 22.78mg.kg-1, Pb: 35.67 mg.kg-1, Zn: 79.48mg.kg-1, much higher than those in similar bays of economically developed coastal areas and lower than those of offshore areas without anthropogenic impact. Average heavy metals in sediment tended to be lower in inner bays than at the mouth of the bay, and higher at aquaculture sites than non-aquaculture ones. However, there was no significant difference among studied bays, suggesting that river input maybe the main source of heavy metals in sea areas around the Nanao Island, which resulted in the enrichment of Cu (Cf = 2.75) and Pb (Cf = 2.27) that are representative elements of sewage. Based on the marine sediment quality standard, sediment quality criteria and baseline values for the United States Pacific Coast, the heavy metal pollution near the Nanao Island generally presented a slightly higher level. However, more attentions should be paid to the potential pollution effects.

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Studies on distribution of fungal endophyte in mangrove plant Aegiceras corniculatum
DENG Zu-jun,CAO Li-xiang,VRIJMOED LILIAN L P,LU Yong-jun,ZHOU Shi-ning
Journal of Tropical Oceanography    2010, 29 (3): 77-81.   DOI: 10.11978/j.issn.1009-5470.2010.03.077
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Five hundred and twenty-nine isolates of fungal endophytes were isolated from the lamina, mid-rib, bark and the xylem of stem of Aegiceras corniculatum, among them 297 isolates in wet and 232 in dry season. The taxa of preponderant fungal endophyte communities differed in the four organs of Aegiceras corniculatum: in lamina are Penicillium and Aureobasidium, in mid-rib are Penicillium and Cladosporium, in bark are the sterile groups, and in xylem of stem are Aureobasidium and Cladosporium. These results indicated that there was some degree of organ specific in distribution of fungal endophytes. The preponderant taxa of endophyte assemblages in organs were different between wet and dry seasons. For example, in lamina, wet season were Penicillium and Aureobasidium, but dry season were sterile groups B and C. It showed that the density and the taxa of the endophyte communities in Aegiceras corniculatum were influenced by the environmental factors such as precipitation, temperature, humidity, and intensity of sunlight.

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