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The East China Sea (ECS) was characterized by nutrient-rich condition, high primary productivity and high fishery yield, due to the massive input of nutrient from Changjiang (CJ). However, the anthropogenic nutrient load from CJ has increased over 10-fold since 1960’s, and caused frequent eutrophication and hypoxia events. In addition, construction of Three Gorges Dam has been proved to reduce the nutrients discharge. The effects of present nutrient status on the benthos assemblage were still obscure. Nevertheless, we presume that the nutrient status in the ECS is still excessive, and may injure the benthos communities in the ECS. To verify our assumption, oceanographic survey was conducted across the inshore-offshore transects. Totally 3935 dermal fish including 71 species were collected by the beam trawl. Fish species composition varied greatly between northern and southern sites as well as between inshore and offshore sites. Higher diversity appeared at offshore sites and lowest diversity occurred at the inshore site close to Changjiang Estuary. The fish community structure among each site was related to depth, latitude, dissolved oxygen, PO4 and NO2. Besides, the fish species diversity is significantly positive correlated to dissolved oxygen and negative to concentrations of various nutrients and chlorophyll a. This result implied that the fish communities were not only determined by specific biogeographic distribution, but also by the nutrients and hypoxia conditions. In conclusion, the nutrient status in the ECS is still redundant, and its follow up consequences, including organic matters accumulation and benthic hypoxia have negatively impacted the community of demersal fish.

In order to understand the demersal fish assemblages and its link to the environments, beam trawl surveys and hydrographic measurements were conducted across the East China Sea continental shelf in 2010 - 2012. The results suggested that the fish assemblages varied with the depth and salinity gradients with significant difference in composition between inshore and offshore areas. Water temperature might be an important factor in shaping the spatial pattern during spring and autumn periods. Bio-indices (e.g. diversity, richness and evenness) showed negative correlations with Chl. a concentrations and nutrients levels and positively correlated with dissolved oxygen. The eutrophication and subsequent hypoxia in the inshore area during summer periods favored the high dominance of opportunistic species (Amblychaeturichthys hexanema). These results suggested the negative impacts of eutrophication and hypoxia on the demersal fish assemblages. Seasonal changes of fish compositions were only found in the inshore area, which may attribute to the succession of dominant species. In addition, we found moderate recovery of fish communities after summer hypoxia but the short-periods of alleviation from stressful condition might not be adequate to compensate the simplified assemblages during hypoxia. Despite the variation of primary productions in different seasons, d13C value of fish muscle suggested that in situ primary production was the main food sources to the demersal fish rather than the terrestrial POM. d15N of demersal fish were higher in autumn than in summer, which might attribute to the preferential uptake of isotopic lighter N source or the shift in baseline rather than elongation of food chain. Our results provided further insights into the demersal fish assemblages in the ECS, and the influences of environmental parameters on fish compositions.

Abstract This essay is mainly to review China’s developing sea power on its relevant of conditions , goal, strategy system of organizing in the 21st century, including decree basis, organization structuring, regulation construction, organization procedure,etc.. This essay also studies and judges how China’s sea power development influences the stability in the Asian Pacific area and vising China’s role. Acording to A.T.Mahan “sea power is a symbol of great power” It is exactly the China in the first 20 years of 21st century marine economic construction and the best period for development of marine cause, build marine strategic opportunity issue of powerful country too, the China’s goal , 2010 total supply and demand close U.S.A. to 2030 year, become the marine powerful country in the Pacific area; Became the marine powerful country of the world from 2030 to 2050, created conditions for becoming medium-sized developed country on the whole in middle period of 21st century and made important contribution finally. This essay tries to proceed from realism, analysize China have pursue the development of sea power from 1949 to 21st centry and reveal meaning to the Asian-Pacific surrounding countries.

Activities of 231Pa and 230Th in surface sediments from the Arctic Ocean and Greenland-Norwegian Seas are used to examine the redistribution of these water-column produced tracers between the low productivity interior basins and high particle flux marginal areas. Sediment 231Paxs/230Thxs ratios throughout the Canadian and Eurasian Basins and the high particle flux Chukchi slope region are essentially invariant (average N = 39) and significantly below the water column production ratio (0.093). 231Paxs/230Thxs ratios are also below the production ratio in the seasonally high productivity Greenland-Norwegian Sea basins (average = 0.082 ± 0.024, N = 13), though they are ∼ 30% higher than the interior Arctic. The low sediment 231Paxs/230Thxs ratios are attributed to the net export of ∼ 39% of dissolved 231Pa produced in intermediate/deep waters, as opposed to ∼ 10% of 230Th, through Fram Strait. The negligible 230Th export, combined with the reported low 230Thxs inventory of basin sediments and high 230Thxs inventory in Chukchi slope sediments, points to significant boundary scavenging of 230Th in the Arctic. The invariant 231Paxs/230 Thxs ratios further indicate that scavenging of 230Th is comparable to 231Pa (i.e., fractionation to a similar degree between the two nuclides) in both the interior basins and margins. Thus, while significant boundary scavenging of both 231Pa and 230Th occurs in the Arctic, there is a distinct lack of basin-margin fractionation and a sizable export of 231Pa. There is also likely to be export of other similarly particle-reactive radionuclides (e.g., 10Be, Pu isotopes) out of the Arctic. © 2005 Elsevier B.V. All rights reserved.

A new analytical method has been developed to determine atomic236U/238U ratios in samples with only femtograms of236U using a secondary electron multiplier (SEM) on a multicollector high-resolution inductively coupled plasma mass spectrometer (MC-ICPMS). The abundance sensitivity of the238U tail at 236 atomic mass unit is reduced from 10-6to 10-10with the deployment of a retarding potential quadrupole lens. This method features the reduction of polyatomic interferences from hydride, nitride, lead, and plutonium and the evaluation of nonlinear SEM behavior. The instrument sensitivity is 1-2%, and the estimated methodological detection limit of the236U/238U atomic ratio is as low as 2 × 10-10. Measurements on reference materials with236U/238U ratios of 10-7-10-9, including the IRMM-075 series and the ETH Zurich in-house standard ZUTRI, demonstrate the accuracy of our MC-ICPMS technique. The analytical precisions (2σ) are ±4% for 5 fg of236U at a236U/238U of 1 × 10-8and ±8% for 2 fg of236U at a236U/238U of 4 × 10-9level. Compared to state-of-the-art accelerator mass spectrometry techniques and triple quadrupole-based ICPMS, our detection limit is not as low, but the required sample size is 3-40 times lower, and the throughput is as high as 3-4 samples per hour. The new MC-ICPMS-SEM technique is sensitive enough for determining236U/238U in various small natural samples, such as marine carbonates and seawater. ? 2021 American Chemical Society

Surface signatures and interior properties of large-amplitude nonlinear internal waves (NLIWs) in the South China Sea (SCS) were measured during a period of weak northeast wind (∼2 m s-1) using shipboard marine radar, an acoustic Doppler current profiler (ADCP), a conductivity - temperature - depth (CTD) profiler, and an echo sounder. In the northern SCS, large-amplitude NLIWs propagating principally westward appear at the tidal periodicity, and their magnitudes are modulated at the spring-neap tidal cycle. The surface scattering strength measured by the marine radar is positively correlated with the local wind speed when NLIWs are absent. When NLIWs approach, the surface scattering strength within the convergence zone is enhanced. The sea surface scattering induced by NLIWs is equivalent to that of a ∼6 m s-1 surface wind speed (i.e., 3 times greater than the actual surface wind speed). The horizontal spatial structure of the enhanced sea surface scattering strength predicts the horizontal spatial structure of the NLIW. The observed average half-amplitude full width of NLIWs λη/2 is 1.09 ± (12 km; the average half-amplitude full width of the enhanced scattering strength λ I/2 is ∼0.57 λη/2. The average half-amplitude full width of the enhanced horizontal velocity convergence of NLIWs λaxu/ 2 is approximately equal to λI/2. The peak of the enhanced surface scattering leads the center of NLIWs by -0.46 λ η/2. NLIW horizontal velocity convergence is positively correlated with the enhancement of the surface scattering strength. NLIW amplitude is positively correlated with the spatial integration of the enhancement of the surface scattering strength within the convergence zone of NLIWs. Empirical formulas are obtained for estimating the horizontal velocity convergence and the amplitude of NLIWs using radar measurements of surface scattering strength. The enhancement of the scattering strength exhibits strong asymmetry; the scattering strength observed from behind the propagating NLIW is 24% less than that observed ahead, presumably caused by the skewness and the breaking of surface waves induced by NLIWs. Above the center of NLIWs, the surface scattering strength is enhanced slightly, associated with isotropic surface waves presumably induced or modified by NLIWs. This analysis concludes that in low-wind conditions remote sensing measurements may provide useful predictions of horizontal velocity convergences, amplitudes, and spatial structures of NLIWs. Further applications and modification of the presented empirical formulas in different conditions of wind speed, surface waves, and NLIWs or with other remote sensing methods are encouraged. © 2008 American Meteorological Society.

Climate-driven changes in land water storage and their contributions to sea level rise have been absent from Intergovernmental Panel on Climate Change sea level budgets owing to observational challenges. Recent advances in satellite measurement of time-variable gravity combined with reconciled global glacier loss estimates enable a disaggregation of continental land mass changes and a quantification of this term. We found that between 2002 and 2014, climate variability resulted in an additional 3200 ± 900 gigatons of water being stored on land. This gain partially offset water losses from ice sheets, glaciers, and groundwater pumping, slowing the rate of sea level rise by 0.71 ± 0.20 millimeters per year. These findings highlight the importance of climate-driven changes in hydrology when assigning attribution to decadal changes in sea level. © 2016, American Association for the Advancement of Science. All rights reserved.

A model experiment monitoring the fate of total residue oxidant (TRO) in water at a constant temperature and salinity indicated that it decayed exponentially with time, and with TRO decaying faster in seawater than in distilled water. The reduction of TRO by temperature (°K) was found to fit a curvilinear relationship in distilled water (r 2 = 0.997) and a linear relationship in seawater (r 2 = 0.996). Based on the decay rate, flow rate, and the length of cooling water flowing through at a given temperature, the TRO level in the cooling water of a power plant could be estimated using the equation developed in this study. This predictive model would provide a benchmark for power plant operators to adjust the addition of chlorine to levels necessary to control bio-fouling of cooling water intake pipelines, but without irritating ambient marine organisms. © 2008 by MDPI.

Simulated regional precipitation, especially extreme precipitation events, and the regional hydrologic budgets over the western North Pacific region during the period from May to June 2008 were investigated with the high-resolution (4-km grid spacing) Weather Research and Forecast (WRF v3.2.1) model with explicit cloud microphysics. The model initial and boundary conditions were derived from the National Centers for Environmental Prediction/Department of Energy (NCEP/DOE) Reanalysis 2 data. The model precipitation results were evaluated against the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis 3B42 product. The results show that the WRF simulations can reasonably reproduce the spatial distributions of daily mean precipitation and rainy days. However, the simulated frequency distributions of rainy days showed an overestimation of light precipitation, an underestimation of moderate to heavy precipitation, but a good representation of extreme precipitation. The downscaling approach was able to add value to the very heavy precipitation over the ocean since the convective processes are resolved by the high-resolution cloud-resolving model. Moreover, the water vapor budget analysis indicates that heavy precipitation is contributed mostly by the stronger moisture convergence; whereas, in less convective periods, the precipitation is more influenced by the surface evaporation. The simulated water vapor budgets imply the importance in the tropical monsoon region of cloud microphysics that affects the precipitation, atmospheric latent heating and, subsequently, the large-scale circulation. © 2013 Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer-Verlag Berlin Heidelberg.

Accurate sea surface flux measurements are crucial for understanding the global water and energy cycles. The oceanic evaporation, which is a major component of the global oceanic fresh water flux, is useful for predicting oceanic circulation and transport. The global Goddard Satellite-based Surface Turbulent Fluxes Version-2 (GSSTF2; July 1987-December 2000) dateset that was officially released in 2001 has been widely used by scientific community for global energy and water cycle research, and regional and short period data analyses. We have recently been funded by NASA to resume processing the GSSTF dataset with an objective of continually producing a uniform dataset of sea surface turbulent fluxes, derived from remote sensing data. The dataset is to be reprocessed and brought up-to-date (GSSTF2b) using improved input datasets such as a recently upgraded NCEP/DOE sea surface temperature reanalysis, and an upgraded surface wind and microwave brightness temperature V6 dataset (Version 6) from the Special Sensor Microwave Imager (SSM/I) produced by Remote Sensing Systems (RSS). A second new product (GSSTF3) is further proposed with a finer temporal (12-h) and spatial (0.25° × 0.25°) resolution. GSSTF2b (July 1987-December 2008) and GSSTF3 (July 1999-December 2009) will be released for the research community to use by late 2009 and early 2011, respectively. © 2009 Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer Berlin Heidelberg.

In the Miocene sandstones of the Nankang Formation in north-eastern Taiwan, different varieties of the trace fossil Ophiomorpha are abundant. In certain beds, a peculiar reworking of vertical Ophiomorpha shafts was observed. This reworking consists of an inner, lined tube positioned in the centre of the shaft. The shaft is lined by thin walls with small knobs and is distinctly different from the shafts of the Ophiomorpha nodosa mazes found in the same beds which have thick walls and large knobs. Because both outer and the inner tube walls were constructed by small sub-pellets, a diagenetic origin can be ruled out. The presence of sub-pellets further indicates that the inner tubes were also constructed by crustaceans and not commensal organisms such as worms or fish. The abundance of these vertical shafts suggests that they were constructed for a specific purpose, and the similarities in sub-pellets indicate that they likely were constructed by different generations of the same crustacean species. Because brooding chambers were not observed and are rare among extant marine crustaceans, we suggest that the vertical shafts were constructed to encourage juvenile shrimp to resettle in the parental burrows after they had completed their pelagic larval stages. © 2015 Taylor and Francis.

The water column distributions of dissolved cadmium and supporting parameters were determined during a cruise in the South China Sea in October, 2002. The investigation was focused on waters of the shelf and the central basin which have depths of <200 m and >2000 m, respectively. In the surface waters, concentrations of Cd were 0.07-0.95 and 0.05-0.15 nM for the shelf and central basin, respectively. The spatial distributions in the surface waters show that concentrations of Cd were relatively high in the Pearl River Estuary. In contrast, Cd was totally depleted in surface waters of the deep water basin. This is attributed to the riverine inputs from the East Asian continent in the shelf regions. The influence of riverine input is reduced by dilution process with waters containing low concentrations of Cd waters. In the central basin, vertical profiles of Cd show a nutrient-like distribution which is depleted in the surface, increases with depth to about 1000 m, and that is finally maintained within a narrow concentration range of 0.94-0.99 nM in the deep water. Here, the Cd/PO 4 ratio was 0.369±0.011 nM Cd/μM PO 4, indicating that the biogeochemical processes of Cd and PO 4 are similar to that in marginal seas of the western Pacific Ocean. However, the concentration gradients in surface waters show a southward increase. The results indicate that the relative enrichment of nutrients and the nutricline uplifted sharply in surface waters of the southern SCS. © 2004 Elsevier Ltd. All rights reserved.

The stable isotope composition of planktonic foraminifera is one of the most important proxies in paleoenvironmental research. In this study, three parameters affecting the stable isotope values of Globigerinoides ruber from surface sediment from the northern South China Sea were tested: different cleaning methods, different morphotypes, and different size fractions. Our results show that in the small size fraction, there is a small but significant effect on δ13C by oxidizing the tests prior to measurement. Our data also confirm a small but significant difference between different morphotypes of G. ruber. However, the variability caused by the seasonal effect stable isotope value is larger than the effect caused by different cleaning protocols or different morphotypes. The large spread of the isotope values (up to 2‰) have some implications to paleoceanographic reconstructions; when measurements are performed on a small number of foraminiferal tests, the isotope value does not necessarily reflect yearly average or a certain season but is a random value of the seasonal variability in that region. © 2005 Elsevier B.V. All rights reserved.

Numerical models of climate have great difficulties with the simulation of marine low clouds in the subtropical Pacific and Atlantic Oceans. It has been especially difficult to reproduce the observed geographical distributions of the different cloud regimes in those regions. The present study discusses mechanisms proposed in previous works for changing one regime into another. One criterion is based on the theory of stratocumulus destruction through cloud top entrainment instability due to buoyancy reversal-situations in which the mixture of two air parcels becomes denser than either of the original parcels due to evaporation of cloud water. Another criterion is based on the existence of decoupling in the boundary layer. When decoupled, the stratocumulus regime changes to another in which these clouds can still exist together with cumulus. In a LES study, the authors have suggested that a combination of those two criteria can be used to diagnose whether, at a location, the cloud regime corresponds to a well-mixed stratocumulus regime, a shallow cumulus regime, or to a transitional regime where the boundary layer is decoupled. The concept is tested in the framework of an atmospheric general circulation model (GCM). It is found that several outstanding features of disagreement between simulation and observation can be interpreted as misrepresentations of the cloud regimes by the GCM. A novel criterion for switching among regimes is proposed to alleviate the effects of these misrepresentations. © 2012 Springer-Verlag.

[1] Abrupt decreases of the Atlantic meridional overturning circulation (MOC) during the Late Pleistocene have been directly linked to catastrophic discharges of glacimarine freshwater, triggering disruption of northward marine heat transport and causing global climate changes. Here we provide measurements of excess sedimentary 231Pa/230Th from a high-accumulation sediment drift deposit in the NE Atlantic that record a sequence of sudden variations in the rate of MOC, associated deep ocean ventilation and surface-ocean climatology. The data series reveal a sequential decrease in the MOC rate at ∼18.0 ka BP ago that coincides with only transient and localized freshwater inputs. This change represents a substantial, though not total, cessation in MOC that predates the major Heinrich (H1) meltwater event by at least 1,200 years. These results highlight the potential of targeted freshwater perturbations in promoting substantial MOC changes without a direct linking with catastrophic freshwater surges. Copyright 2006 by the American Geophysical Union.

Modern acidification by the uptake of anthropogenic CO 2 can profoundly affect the physiology of marine organisms and the structure of ocean ecosystems. Centennial-scale global and regional influences of anthropogenic CO 2 remain largely unknown due to limited instrumental pH records. Here we present coral boron isotope-inferred pH records for two periods from the South China Sea: AD 1048-1079 and AD 1838-2001. There are no significant pH differences between the first period at the Medieval Warm Period and AD 1830-1870. However, we find anomalous and unprecedented acidification during the 20th century, pacing the observed increase in atmospheric CO 2. Moreover, pH value also varies in phase with inter-decadal changes in Asian Winter Monsoon intensity. As the level of atmospheric CO 2 keeps rising, the coupling global warming via weakening the winter monsoon intensity could exacerbate acidification of the South China Sea and threaten this expansive shallow water marine ecosystem.

Purple clams (Hiatula diphos Linnaeus) accumulate paralytic shellfish poisoning (PSP) toxins produced by a toxic strain of the dinoflagellate Alexandrium minutum Halim in a laboratory study. The maximal toxicity of PSP toxins attained 31.3 MU/g after 20 days exposure. The toxin profile of H. diphos was similar to that reported for A. minutum at the end of the exposure period; and GTX1 was dominant. GTX congeners were found in muscle on day 16 and day 20, these substances could be detected during the depuration period as well. GTX1 was detected in the siphon only on day 32. The results show that H. diphos accumulates PSP toxins according to the amount and toxin profile of ingested A. minutum. © 2005 Elsevier Ltd. All rights reserved.