Induction of volatile organic compound in the leaves of Lycopersicon esculentum by chitosan oligomer

Induction of VOCs (volatile organic compounds) in the leaves of Lycopersicon esculentum by chitosan oligomer elictor was studied. The results demonstrated that VOCs in chitosan oligomer-treated leaves showed stronger inhibitory activity against Botrytis cinerea than that in water-treated leaves, and the spore germination was reduced by 22.1% in 144h after elicitor treatment at a concentration of 1.0%. A total of 16 constituents were detected in water-treated leaves, and chitosan oligomer treatment increased the amount of VOCs production. Chitosan oligomer at different concentration and different time courses of induction treatment could induce different amount of VOCs. Chitosan oligomer resulted in an optimal production of VOCs in 144h after elicitation at concentration of 0.6%. Chitosan oligomer also enhanced activtity of PAL and LOX. The results showed that the enhancement of VOCs production after chitosan oligomer treatment might be an important agent for L.esculentum acquiring resistance against pathogen.

Cyst Formation, Development of Alexandrium tamarense from Yangtse River Estuary and Its Relation to Bloom Dynamics

The toxic dinoflagellate—Alexandrium tamarense (Lebour) Balech, formed resting cysts in f/2 media with low nitrate concentrations. Among the concentrations tested, f/20 NO3^- was the most effective to induction with an encystment percentage of 2.0 in batch culture. About 73.2% and 17.6% of cysts were produced on 8 and 9 d after transferring. Newly formed cysts developed accumulation body 3d later and kept forming mucilaginous substance, which might help their dispersal and survival. The mandatory dormancy period of resting cysts was 15 and 10d when stored at 15 and 20℃ respectively. The cysts could germinate without temperature change, with germination of 75.6% 20d after formation at 20℃. The Alexandrium cyst density in the surface sediment of DG-26 station reached above 25 cysts/g in May and November of 2002, and dropped to 4.5 and 0.9 cysts/g in August of 2002 and February of 2003, suggesting that Alexandrium cysts might have germinated in spring and autumn 2002. Cysts produced during the bloom returned to water column soon, whatever the season and water temperature were. The cyst density in the surface sediment at DG-26 station in May, 2003 was only 3.3 cysts/g and the cysts were newly formed. In the Yangtse River estuary, the inoculum size was not a major factor to determine the outbreak of A.tamarense bloom.

NUMERICAL MODELLING OF THE QUASI-GLOBAL OCEAN CIRCULATION BASED ON POM

A free surface quasi-global ocean circulation model, Princeton Ocean Model(POM), was adopted to simulate the climatological circulation. The horizontal resolution of themodel was 1/2° x 1/2° with 16 vertical sigma layers. The initial temperature and salinity fieldsof the model were interpolated from the Levitus data, and the COADS (Comprehensive Ocean-AtmosphereData Set) monthly mean SST and wind fields were used as the surface forcing. The integral timelength is 6a. The main general circulation components such as the equatorial current, the equatorialundercurrent, the south and north equatorial currents, the Antarctic Circumpolar Current (ACC), theKuroshio and the Gulf Stream were well reconstructed. The volume transports of PN section and ACCa-gree well with the estimations on field survey. Up to now there is no global or quasi-globalcirculation model results u-sing POM in literature. Our results demonstrate that POM has soundability to simulate the coastal circulation as well as the general ocean circulation. And thisresult can provide open boundary conditions for fine resolution regional ocean circulation models.

Assessment of Genetic Diversities of Selected Laminaria （Laminariales, Phaeophyta） Gametophytes by Inter-Simple Sequence Repeat Analysis

Abstract: Inter-simple sequence repeat (ISSR) analysis was used to assess genetic diversity among 10 pairs of male and female Laminaria gametophytes. A total of 58 amplification loci was obtained from 10 selected ISSR primers, of which 34 revealed polymorphism among the gametophytes. Genetic distances were calculated with the Dice coefficient ranging from 0.006 to 0.223. A dendrogram based on the unweighted pair-group method arithmetic (UPGMA) average showed that most male and female gametophytes of the same species were clustered together and that 10 pairs of gametophytes were divided into four groups. This was generally consistent with the taxonomic categories. The main group consisted of six pairs of gametophytes, which were selected from Laminaria japonica Aresch. by intensive inbreeding through artificial hybridization. One specific marker was cloned, but was not converted successfully into a sequence characterized amplified region (SCAR) marker. Our results demonstrate the feasibility of applying ISSR markers to evaluate Laminaria germplasm diversities.

LATITUDINAL VARIATION OF DEEP SCATTERING LAYER IN THE WESTERN PACIFIC

The acoustic Echo Intensity (EI) was recorded with 38k shipborne AcousticDoppler Current Profiler (AD-CP) in the Western Pacific in four cruises between Sept. 2001 and Oct.2002. The main Deep Scattering Layer (DSL) was observed at 400m-600 m depth in the four cruises. Thelatitudinal variation of the main DSL, which has high level of back-scatter strength (BS) at highlatitude, is prominent during both nighttime and daytime. The influences of environmental conditionson the DSL are discussed. Since high-oxygen water in the north is a friendly environment of marineanimals which form the main DSL, more animals are expected to aggregate in the 400dbars-600dbarslayer in the north. Dissolved Oxygen (DO) is the principal factor that causes the main DSL to varywith latitude, and its spatial distributions result from formation and transport of North PacificIntermediate Water (NPIW).

THREE-DIMENSIONAL NUMERICAL SIMULATION OF TIDES AND CURRENTS IN FUSHAN BAY, QINGDAO

The three-dimensional Princeton Ocean Model (POM) was employed to simulatethe tide and current simul-tanuously for the first time in the Fushan Bay, Qingdao, China. Byadopting the elevation condition that was combined with the tides M2, S2, K1 and O1 at the openboundary and by choosing the proper value of bottom roughness, the horizontal and verticaldistributions of the tidal current and water level variations in the bay were computed. The resultsagree well with the field observation data, indicating that this model can be used to predictaccurately the variation of tides and currents in the Fushan Bay and other costal regions in thefuture. Our study also provides useful information and a data base for the Olympic Projects thatwill be conducted in the Fushan Bay in 2008.

EI NIO PHENOMENON AND EXTENDED ASSOCIATE PATTERN ANALYSIS

To study the causes of El Nino Phenomenon the Extended Associate PatternAnalysis (EAPA) is set up with monthly sea surface wind stress and precipitation besides Sea LevelPressure (SLP) and Sea Surface Temperature (SST) in or over the Pacific and related seas since 1979in present paper. The results show that El Nino Phenomenon means a SST redistribution, coveringalmost the whole Pacific that needs a huge amount of energy provided by air-sea interaction in themost Pacific regions; It is the wester burst and wind convergence, coming from meddle latitudesdirectly, instead of Kelvin waves that produce the strong SST warm signal in Nino regions; Twonegative SLP anomalies in middle of the North and South Pacific, most likely produced by the averageair pressure decreasing effect of explosive cyclones through precipitation, and the positive SLPanomaly o-ver the Asia-Australia land bridge, coming mainly from the south hemisphere with a littleinfluence from the Asian continent, are the three major causes for El Nino onset, they work togetherto produce anomalous wind convergence in Nino regions and wester burst in middle of the North andSouth Pacific that result in a warm tongue and cold pincers gearing together; Basically, during itsearly stage the ocean is forced by the atmosphere, while during its late stage the atmosphere isforced by the ocean.

SEASONAL VARIABILITY OF THE INDONESIAN THROUGHFLOW FROM A VARIABLE-GRID GLOBAL OCEAN MODEL

The objective of this study is to model the mean and seasonal mass transportof the Pacific to Indian O-cean throughflow using variable-grid global Ocean General CirculationModel (OGCM) with fine grid (1°/6) covering the area from 20°S to 60°N and from 98°E to 156°E.The computations show that Indonesian Throughflow (ITF) mass transport, computed as a sum ofthrough-strait transport, has maximum transport in Sept. (17. 5Sv) and minimum transport in Jan. (9.5Sv). The annual mean ITF transport amounts to 14. 5Sv. Twenty-two percent of this transport passesthrough Lombok Strait. Sixty-five percent of this transport passes through Timor Passage.Semi-annual variability is apparent in Lombok and Ombai Straits while annual variability is apparentin Timor Passage.

NUMERICAL SIMULATION OF THE TIDAL MOTION AND SUSPENDED SEDIMENT TRANSPORT IN THE RADIAL SANDBANK AREA OF THE SOUTHERN YELLOW SEA

A coupled 2-D numerical model for hydrody-namic-sediment transport wasestablished and applied to simulate the tides, tidal currents and sediment movement in the submarineRadial Sandbank area of the southern Yellow Sea. With a high-resolution topography dataset used inthe model, the simulation reproduced a fine-structured current field and e-rosion-siltationdistribution. The modeled results show that, in the area of Radial Sandbanks, reversing tidalcurrent and seabed erosion occurs within troughs while tidal current with more rotary feature anddeposition occurs above sandbanks, which indicates the tidal-induced formation of the RadialSandbanks. During a tidal period, associating with the variation of current speed, erosionalternates with siltation. The seabed deformation depends on the relative strength of erosion andsiltation in a tidal period.

UNIFICATION AND APPLICATIONS OF MODERN OCEANIC/ATMOSPHERIC DATA ASSIMILATION ALGORITHMS

The key mathematics and applications of various modern atmospheric/oceanicdata assimilation methods including Optimal Interpolation (OI), 4-dimensional variational approach(4D-Var) and filters were systematically reviewed and classified. Based on the data assimilationphilosophy, i. e. , using model dynamics to extract the observational information, the commoncharacter of the problem, such as the probabilistic nature of the evolution of theatmospheric/oceanic system, noisy and irregularly spaced observations, and the advantages anddisadvantages of these data assimilation algorithms, were discussed. In the filtering framework, allmodern data assimilation algorithms were unified: OI/3D-Var is a stationary filter, 4D-Var is alinear (Kalman) filter and an ensemble of Kalman filters is able to construct a nonlinear filter.The nonlinear filter such as the Ensemble Kalman Filter (EN-KF), Ensemble Adjustment Kalman Filter(EAKF) and Ensemble Transformation Kalman Filter (ETKF) can, to some extent, account for thenon-Gaussian information of the prior distribution from the model. The flow-dependent covarianceestimated by an ensemble filter may be introduced to OI and 4D-Var to improve these traditionalalgorithms. In practice, the performance of algorithms may depend on the specific numerical modeland the choice of algorithm may depend on the specific problem. However, the unification ofalgorithms allows us to establish a unified test system to evaluate these algorithms, which providesmore insights into data assimilation philosophies and helps improve data assimilation techniques.

ANALYTIC METHOD FOR INVERSING THE OPEN BOUNDARY CONDITIONS IN A SEMI-CLOSED SEA AREA—CASE I FOR INVERSING THE TIDAL LEVELS AT OPEN BOUNDARY

In this paper, a computational case was employed to describe thecomputational procedure for inversing the tidal level open boundary conditions using an analyticmethod. The area for finding the solution is a circular area with a circular arc with the openingangle 60°-being the open boundary and the other circular arc being the solid wall boundary.Proceeding from the reestablished elliptic partial differential equation satisfied by the tidallevel function, the extended spectrum method was used to derive the general solution of the equationfor the sea of constant depth, and the impermeable solid wall condition (the second class boundarycondition) and the adequately specified open boundary conditions were then applied to determine theundetermined coefficients of the general solution, thus obtaining the tidal level distributionfunction. In this way, both the first and second class boundary values at the solid wall boundarywere obtained. With the above boundary values as the boundary conditions, the tidal level values atthe open boundary were then inversed by means of the general solution of tidal wave equation. Thevalidity of inversion method could be verified by comparing the inversed tidal level distributionswith the originally specified open boundary values.

DYNAMICS OF THE ZONAL ASYMMETRIC STRUCTURE OF ARCTIC OSCILLATION

The Arctic Oscillation (AO), though basically is a zonal symmetricphenomenon, also shows zonal asymmetric variation. The dynamics of this zonal variation isconsidered here from the point of view of the planetary propagation on the earth sphere. Based onthe linear barotropic vorticity e-quation, the planetary wave ray path is calculated in the winterJanuary. It shows that NAO( North Atlantic Oscillation), AO and North Pacific could be linkedthrough the planetary wave propagation, which acts as the atmospheric bridge. The zonal symmetricand asymmetric structures both have association with these Rossby wave activities.

CORRELATION BETWEEN ASO AND AAO

Using a 34 years database consisting of sea level pressure and sea iceconcentration, the relationship between Antarctic Oscillation (AAO) and Antarctic Sea-iceOscillation (ASO) was investigated. Firstly, Empirical Orthogonal Function (EOF) analysis depictsthe spatial variability of AAO and ASO and Antarctic Sea-ice Oscillation Index (ASOI) was definedfor the first time. Secondly, power spectrum and head-lag correlation analysis show that ASO and AAOhave the same periods of quasi-three years, quasi-one year and quasi-half a year. Corresponding toAAO, ASO has an evident anti-oscillation after one and half a year.

STUDY OF NON-BOUSSINESQ EFFCET ON SEA SURFACE HEIGHT

A set of equations was derived for a non-Boussinesq ocean model in thispaper. A new time-splitting scheme was introduced which incorporates the 4th-order Runge-Kuttaexplicit scheme of low-frequency mode and an implicit scheme of high-frequency mode. With thismodel, potential temperature, salinity fields and sea surface height were calculated simultaneouslysuch that the numerical error of extrapolation of density field from the current time level to thenext one could be reduced while using the equation of mass conservation to determine sea surfaceheight. The non-Bouss-inesq effect on the density field and sea surface height was estimated bynumerical experiments in the final part of this paper.

SEASONAL REVERSE OF SEA SURFACE SLOPE IN THE NORTHERN YELLOW SEA AND ITS DYNAMIC RELATION WITH MONSOON EFFECTS

Based on the monthly average sea level data from the tide gauge measurement(1999-2001), the seasonal variability of the sea level in the Northern and Middle Yellow Sea isstudied to reveal that the sea surface height at all the tide gauges becomes higher in summer thanthat in winter. In addition, the sea surface height of the Northern Yellow Sea is higher than theone of the Middle Yellow Sea with a slope downward from the north to the south in summer, while itis lower with a reversed slope in winter. The seasonal reverse of the sea surface slope can beattributed to the monsoon effects i. e. the annual reverse of the monsoon direction and the annualvariation of the monsoon rainfall. A set of equations are established in light of the dynamicprinciples to expound how the monsoon forcing and the sea surface slope generate a summer outflowand a winter inflow in the Yellow Sea.

A UNIVERSAL IN TAILING WAVETRAIN GENERATION

A universal in tailing wave-train generation of forced soliton generationover topography is found theoretically as the flows are at the resonant points and it is examinedwith the numerical calculation of the corresponding fKdV e-quatioa From the comparisons, it is shownthat theoretical and numerical results on the invariance is in good agreement and the theory givenin this paper does not include the modulus truncation, any free constant and unknown function.

SURFACE WAVE PATTERNS AND INSTABILITY IN A VERTICALLY OSCILLATING CIRCULAR CYLINDRICAL VESSEL

The natural frequency of surface wave, which has been derived from avertically oscillating circular cylindrical vessel in inviscid fluid, was modified by consideringthe influence of surface tension and weak viscosity. Many flow patterns were found at differentforced frequencies by numerical computation. In addition, the nonlinear amplitude equation derivedin inviscid fluid was modified by adding viscous damping and the unstable regions were determined bystability analysis.