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Based on the oceanic and atmospheric parameters retrieved from the satellite remote-sensing datawith the neural network method,the air-sea heat fluxes over the western Pacific warm poo area were calculated with the advanced method of CORARE 3.0 bulk algorithm. The variation of multiyear averagedfield and climate field as well as the interannual and interdecadal variation of the air-sea heat fluxes wereanalyzed first,and their relations with the onset of the SCS summer monsoon were discussed primarily. Theresults indicate that the air-sea heat fluxes have obvious characteristics of temporal and spatial distribution.The maximum sensible heat flux occurs in the Kuroshio area,while that of the latent heat flux in the NorthEquator Current and the Kuroshio areas. And the distribution of the averaged annual air-sea heat fluxesshows that both the sensible heat flux and latent heat flux in Kuroshio area have maximum value in winter andminimum value in summer, while the latent heat flux in western Pacific warm pool area has maximum value inautumn and winter,minimum value in spring and summer, and the sensible heat flux has the minimum inspring and basically the same values in other seasons.Furthermore,the air-sea heat fluxes have obviousinterannual and interdecadal variations. Both the sensible heat flux and latent heat flux have l6 a period,which is the same as the SCS summer monsoon onset. The correlation analysis shows that there is a closecorrelation between the air-sea heat fluxes in April in the warm pool area and the onset of SCS summermonsoon three years later.And the lag-correlation could be used to predict the onset of SCS summer monsoonand provide scientific basis for the estimation of precipitation in the flood season.Based on these results,amultivariate regression equation was established to predict the onset of the SCS summer monsoon in 2012,which shows that it will be l~2 pentads later than the normal year.

Based on nine years (2000-2008) of gridded Argo(G-Argo) temperature and salinity data from China Argo Real-time Data Center,the climatological distribution and low-frequency variability of the barrierlayer thickness(BLT) of the tropical Pacific Ocean was analyzed. The climatological mean BLT distribution ischaracterized by relatively large values in the western Pacific warm pool,and three latitudinal bands thatextends from the warm pool to 120°w,centered at approximately 15°N,5°N,12S,respectively. The leadingEOF modes indicate that the low-frequency variability of the tropical Pacific BLT is dominated by seasonal andinterannual signals. For the seasonal time scale,the most pronounced mode is an antiphase BLT pattern atthe latitudinal bands along 15°N and 12'S,with the largest (smallest) thickness in winter (summer) at therespective hemisphere.For the interannual time scale,there are two important modes of BLT variability,onelocated near the eastern boundary of the warm pool with a strong correlation to ENSO, and the other centeredat the middle of the warm pool,probably related to TBO.

East Asian monsoon is an important component of the Asian monsoon system.To understand itscharacteristics is crucial for improving the forecast of rain and drought in China and other Asian areas.Basedon the monthly precipitation data from the Global Precipitation Climatology Project(GPCP) and reanalysis data from the National Centers for Environmental Prediction (NCEP-2),seasonal and interannual varia1onsof the East Asian monsoon were discussed with the East Asian Monsoon Index (EAMI) and Multivariable Empirical Orthogonal Function analysis method(MV-EOF). The result shows that East Asian monsoon hasan evident annual cycle,that is,the summer monsoon prevails from May to September with its peak inAugust,while the winter monsoon reaches the maximum in January. The interannual variation of East Asian Summer Monsoon Index(EASMI)is closely related to the precipitation of the East ASian area.A staiSUcalforecast based on Markov Model to forecast the East Asian Monsoon was made and it successfully forecasted the precipitation anomaly in the summer of 1998 three months ahead of time.

Based on the successive data of sea level and current velocity profiles obtained by two bottom-moored Acoustic Doppler Current Profilers (ADCP) from May to July of 2009 at D8 and D9 stations off the Sanmen Bay, the characteristics of tide and tidal current were investigated with power spectral analysis and harmonic analysis. The results show that the tide is regular semi-diurnal tide, shallow water tides at inshore area of D9 station is much more significant than that at offshore area of D8 station, and that the tide presents the characteristics of tropical tide. The semi-diurnal tidal currents off the Sanmen Bay are the strongest constituents, the tidal currents at different layers have the feature of rotary currents with the ellipticity increasing with depth, and the maximum velocity of both M₂ and K₁ constituents appears in subsurface. The occurrence of the maximum current in the bottom layer is about 30 minutes ahead of that in the middle and surface layers. The semidiurnal constituent in this area is mainly barotropic, while the diurnal one is of baroclinic feature.

Catastrophic storm surge inundation resulted from 9417 typhoon was simulated with an numerical model of ultrahigh resolution for storm surge inundation which is based on unstructured grid and can calculate the overflow discharge. The results agree well with the observations. Three paths of south, mid and north with that of 9417 typhoon as the south-path and 30 km interval from one another were designed for a series of numerical simulations with the strength of 9417 typhoon, which show that the coastal dike in Wenzhou has enhanced the menace of storm surge and inundation on the city, and the inundation depth caused by the south path and the inundation area caused by the mid path is the most. The reason is that the obstruction and diffluence of the dike on the propagation of the storm surge from open sea at the costal waters and Oujiang river estuary multiply the water transfer into the north side of Oujiang river estuary, the north end of the estuary and its mid and upper reaches.

Tidal trenchs are important channel for material transport and water energy exchange in theintertidal zone. In this study,TM and ETM remote sensing (RS) images of 1994,2000 and 2009 and GIStechnology were used to define the plane morphology and calculate the length and density of the tidaltrenches;RTK-GPS was used to make in situ measurements of topography for determining a typical tidaltrench development hight,width,depth,width-depth ratio and longitudinal variation of the cross-sectionarea; and GIS was used to establish the DEM model of the trench.The results show that (l) in the easternChongming tidal flat, tidal trenches are developed mainly in the salt marsh,and the northern and middle partsof the tidal flat are dominated by single and slightly curved ones,whereas the southern part by dendritic ones;(2) the total length and density of the tidal trenches in 1994 were 30.9 km and 717 m/km² respectively,theydecreased to ll.l km and 459 m/km² in 2000 because of reclamation of the upper salt marsh and increased to31.8 km and 98l m/km³ in 2009 due to seaward silting of the salt marsh,which reflect the impacts of naturalaction and human activities on the flat;(3) not like the typical evolutionary feature of lateral movement inEurope and America,the evolution of the tidal trenches in the eastern Chongming tidal flat is mainlycharacterized by successive longitudinal extension (with the sea ward silting of the salt marsh); (4) from themouth of the tidal trenches upward,the ratio of width to depth decreased from >340 to≤<18,and the depthfirst increased and then decreased. This study shows that 3S technology has advantages over traditionalmethods in quantitative study of large spatial and temporal scale evolution of tidal trenches.

In recent years,the hydrodynamics and riverbed topography of the Changijiang River Estuary isinevitably experiencing some new changes due to the decrease of the runoff and sediment load.Successive 9-days fixed point observations during neap-mean-spring tide show that the sediment content was relatively lowfor neap tide,increased with the increase of flow velocity and was higher for spring tide,which indicatedevident sediment resuspension.Analysis of the observed data gave out empirical formula of sediment carryingcapacity of neap,mean and spring tides for the South and North Channels of the Changijiang River Estuary, and showed good correlation between the sediment content and tidal current, and also good correspondence oftheir power changes.

Based on the underwater topography data of 1979,1996 and 2009, the scour and siltation of the tidal flat, subaqueous shore slope and deep trough to the west of Daishan channel were studied with GIS software for two different periods. The results show that the range of scour and siltation for the most part of the research area was ±1 m from 1979 to 1996, only part of the deep trough was more than 2 m; from 1996 to 2009, the scour and siltation of the tidal flat was similar to that from 1979 to 1996 with a range of -1 ~1 m, but the scour and siltation of the subaqueous shore slope and deep trough was obviously enhanced with an average range of 2 m for the slope and 3 m for the trough. Analysis show that there are two main reasons for the enhancement of the scour of the subaqueous shore slope and deep trough after 1996: the first one is the high flow speed of the Daishan channel and the clay bottom material, and the second is the construction of wharf and jetty at the tidal flat and subaqueous shore slope, which blocked the flow in the shallow water and increased the flow speed in the deep water, which enhanced the scour and siltation of the subaqueous shore slope and deep trough.

Base on the Radarsat-2 full polarimetric SAR data and the observed chlorophyll a data from the seasurface of the Pearl River Estuary, and using microwave scattering theory and the Cloude-Pottier theory, theSAR images were decomposed,which resulted in the average scattering angle a and scattering entropies H andVH, VV.HH and HV. A mathematical relationship model between the six parameters and the chlorophyll amass concentration was established using the BP artificial neural network model,and combined with themeasured data the chlorophyll a mass concentration was classified. The results shows that the net workstructure has a good result of the inversion to the chlorophyll a mass concentration when the hidden layernodes is 9,the transmit function of the input layer and the hidden layer is tansig and logsig respectively andthe learning rate and the momentum coefficient are both 0.2,namely, the determination coefficient betweenthe measured data and the predicted data of the chlorophyll a mass concentration (R²) is 0.826. When themodel was applied to two images of different period for verification,it worked well, and the results were ingood accordance with the actual situation.

The ulcer disease of the large yellow croaker is mainly caused by Vibrio alginolyticus, V. harveyi and V. parahaemolyticus. In order to understand the immune response mechanism of resistance to pathogen infection of the large yellow croaker and provide important theoretical basis for their disease prevention, healthy croakers were divided into tree experimental groups injected with 0.2 mL V. harveyi, V. alginolyticus and V. parahaemolyticus respectively, and one control group with the same dose of sterile saline. Then samples were taken at the 0, 1st, 2nd, 4th, 7th, 10th, 13th, 16th and 20th days after infection, and the activity of 7 different immunity-related enzymes in the serum were measured and the differences of effect on large yellow croaker by the three pathogenic vibrios were compared. The results showed that from 1 to 10 days after infection, the activity of LSZ, ACP, POD and MPO in Pseudosciaena crocea's serum increased in the first few days, then decreased and increased again, and reached unanimity finally. The experiments also indicated that different pathogens had time-difference effect, and that AKP was more sensitive to V. harveyi infection, while ACP, POD and MPO were more sensitive to V. alginolyticus infection and LSZ and PO were more sensitive to V. parahaemolyticus infection.

The heart,spleen,kidney,liver,intestine and gill from Sciaenops ocellatus infected with kidneyintumesce were pathologically analyzed by tissue slice and ultramicrocut electron microscopy techniques,so asto study the pathological changes of the tissues and the pathogenic mechanism of this disease.The anatomicalsymptoms of the diseased Sciaenops ocellatus are body surface ulceration,some lumps on the pterygiophore ofsome diseased fish,distinctly enlarged kidney (some 10 times as large as the normal one),enlarged liver,spleen and gallbladder, and white nodules on the viscera of some diseased fish.Histopathology shows that themain manifestations were typical granuloma,infiltration of large amount of inflammatory cells,rupture andnecrosis of the tubular wall of the renal tubule,parenchyma hyperemia and vacuolar degeneration of theparenchymal cells in the liver,and abundant diseased erythrocyte appeared in the spleen with hyperemia andfatty degeneration. Ultrastructure pathology shows serious apoptosis of the epithelial cells of the kidneyproximal tubule,sparse and ruptured brush border in the renal tubule,serious necrosis and blurredboundaries of the liver sell,and expansion of the splenic sinus of the spleen tissue,as well as abundantapoptosis cells of erythrocyte and lymphocytes. The results indicate that pathological changes widely occur intissue cells of the kidney intumesce Sciaenops ocellatus and cause serious damage to the body organs,whichmakes the infected fish lose normal physiological metabolism and died at last.

Using molecular phylogenetic methodology with gene sequence fragments of 18S rDNA and subunitl of C enzyme oxide of mitochondrial dell pigment(CO I) as the molecular mark and combined withmorphological character,evolutionary history of selected brachyuran crabs were discussed. Totally 10 18SrDNA sequnces and 5 CO I gene fragments were obtained by Polymerase Chain Reaction (PCR),andsummited to the Genebank. The length of 18S rDNA sequences from 10 crabs,ranges from 1 780 to l787 bp,in which the shortest one is Hemigrapsus sinensis, the longest one is Parthenope validus. In the 18S rDNAsequnces, the average content of base A,T,G and C is 23.72%,24.58%,24.52%,and 27.17% separately.Sequence alignment shows that 18S rDNA sequences are relatively conservative,containing only onehypervariable region of about 50 bp between 88 bp and 130 bp. The base distance of the species is very small,from 0.001 to 0.017.The phylogenetic trees of 18S rDNA give molecular biological proof for the same originof Grapsioidea,Ocypodioidea and Portunoidea, and also support moving the Helice crab from Sesarminae toVaruninae.The length of mitochondrial DNA sequence from 5 charybdis crabs is 709 bp,and the averagecontent of the base A,T,G and C is 26.88%,37.62%,17.50% and 18.00%separately.The fragment ofco I gene has high species variability,more suitable for the study of the interspecific evolutionary history.The base distance of the charybdis is long,from 0.016 to 0.138.The phylogenetic trees of CO I gene truereflect the evolutionary relations of different charybdis species and are concordant with traditional taxology.This provides a molecular method for the identification of charybdis species of similar morphologicalcharact ers.