A histological and ultrastructural study was performed on the development of the head kidney,thymus,and spleen in Pseudosciaena crocea aging in range from just hatching to the 60th day after hatching(DAH).Head kidney was first present on the 3rd DAH.Primordial haemopoietic stem cells were first observed in the head kidney which rapidly differentiate into different cellular types.Progenitor spleen was present on the 4th DAH,located close to the gut,which soon became rich in blood capillaries,red blood cells and thrombocytes.The thymus was obvious on the 4th DAH,and was located on either side of the upper corner of the opercular cavity,closely under the membrance of the opercuhr cavity.The thymus was the last lymphoid organ to appear but showed a quick development.This organ seemed to originate from haemopoietic stem cells migrating from the head region of the kidney.The thymus consisted of outer thymocytic and inner epithelioid zones.There was no obvious demarcation between them,but both zones were visible.Small lymphocytes appeared,or lymphoid organs become lymphoid,in the sequence thymus,head kidney and spleen.Only a small number of lymphocytes appeared in the later stages.Non-specific systems may play an important role in the immunocompetence mechanisms of P.crocea during its early development stage.

The development of embryos and larvae of Babylonia formosae habei living along the southeast coast of China is observed under laboratory conditions.The egg masses are laid by females on hard substrate at night and each capsule contains 100-500 eggs.Each egg is 250-280 mm in diameter.The first two cleavages of the embryo are meridional and equal,and a polar lobe is produced.Larval kidney,which only consists of a single cell,appears during the gastrula stage on each side of the embryo.The right tentacle develops prior to the left one.At 25-27℃,an intracapsulate veliger stage is reached about 4.5 d after deposition.The larvae hatch on the fifth day as swimming veligers with a shell length of 360-500 mm.The newly hatched larva can ingest suspended algal cells from the water column and remains in the pelagic stage for 8-10 d.The newly settled juveniles are 900-1 200 mm in shell length.

Brown tides have recurred in estuary areas globally, but trophic interactions between the causative species Aureococcus anophagefferens and planktonic copepods remain poorly understood. In this study, we investigated performance (ingestion, growth, development and reproduction) of the planktonic copepod, Pseudodiaptomus poplesia, offered either mono-algal or mixed-algal diets containing a Chinese strain of A. anophagefferens. A typical Michaelis-Menten pattern existed between ingestion rate and food level when copepod fed on the mono-algal diet of this species. Nauplii exhibited the highest maximum ingestion rate (I_max) than copepodids and adult females. In addition, I_max value was higher in nauplii feeding on A. anophagefferens than on Skeletonema costatum. When fed mixtures of A. anophagefferens and S. costatum, P. poplesia selected against A. anophagefferens cells, but less strongly at the naupliar stage. Nauplii did not undergo metamorphosis and died at late naupliar stages feeding on A. anophagefferens alone, similar to those under starvation. Furthermore, the presence of A. anophagefferens greatly reduced the reproduction rate of females in mixtures but did not influence the growth rate of copepodids. These results suggest that P. poplesia nauplii may exert grazing pressure on A. anophagefferens population during a brown tide, which, however, may not be persistent because of copepod population decline.

The development rate of Labidocera euchaeta Giesbrecht in the Xiamen Harbor was studied in laboratory.The results showed that the development times of egg and larval stages (D) were significantly correlated with temperature (TO13), following the Belehradek function, D=α(T-7.5)^-1.0634.The development time from egg to larval stages and adult, as well as generation time can be predicted from the equation for egg development (α=411/24) by appropriately multipling the constant (α) with a proportion.The development was not isochronal over the whole larval period.Durations of naupliar stages were short and quasi-isochronal, which favored their non-feeding development.In contrast, durations of copepodid stages (C) were long.CV had the longest duration followed by CI, both of which are considered as the critical stages in the larval development.The acclimation effect of the seasonal temperature on the development rate was also observed.

Isozyme changes during early development of Penaeus chinensis are described for six enzymes (EST, AMY MDH, GDH, Gd and LDH) by means of polyacrylamide gel vertical plate electrophoresis. The results show that the number of isozymes varies considerably and the enzyme activity also rises gradually with development. The band number of EST increases from 1 in nauplius stage to 6 in postlarval stage. There are three types of AMY, α-AMY, R-AMY and Q-AMY. The phenotype of LDH changes slightly, showing the same pattern except nauplius in all the stages. The remaining three enzymes (MDH, Gd and GDH) have more bands and their isozyme number also increases with development.

Using meteorological data of field observation in 1990-2000,especially polar orbit highresolution NOAA satellite cloud maps received from the Antarctic expedition vessel since 1997,the formation and development of the Prydz Bay cyclone are studied in this paper.Some new viewpoints are suggested such as:when surround-polar cyclone enters the Prydz Bay,it can also intensify and develop in summer; cyclone can also develop in the easterlies in this bay.These view points revise old uncomplete view point that the Prydz Bay is a burial ground of cyclone,and also further consummate formation-development theory of surround-cyclone in the Antarctic westerlies and cyclone in the Antarctic easterlies.In this paper,the mechanism of ice-air-sea interaction in the Prydz Bay is studied,and the physical process of cyclone formation-development is explained.By use of wholly dynamic transportation method,an energy exchange case of a cyclone,which explosively developed after entering the Prydz Bay,is calcu caculated.In the open water area,momentum flux is-2.205 N/m².sensible heat flux is 486.69 W/m²,and latent heat flux is 261.84 W/m².It is larger than values of westerlies burst over the Pacific.The heat transferred from ocean to atmosphere in form of sensible and latent heat promotes cyclone development rapidly.In this case wind force was as strong as 12 grade,with 10 minutes average wind speed of 38 m/s,and instantaneous wind speed of 100 m/s which broke the wind speed record of 96 m/s in the Antarctic (Wendler and Kodama).

Fences have been widely used in coastal protection engineering for their low cost, simple deployment, and easy integration with ecosystems. The effects of fence porosity and height on dune development have been investigated while not much attention has been paid to the effects of fence opening configurations, such as opening size and geometry, and porosity distributions. In this study, we deployed eight fences with same height and similar porosity, but different opening configurations on a sandy beach in Pingtan, Fujian Province. Results indicate that there is a similar two-dune-one-trough pattern for all fences at the beginning of dune development, and opening size, orientation, and geometry, and porosity distribution control the leeward dune peak locations. Fences with small openings and non-uniform porosity have high trapping efficiency, and upper denser porosity may be the optimal design as these fences have the highest trapping efficiency and capacity. The conclusions from this study can provide guidance on practical fence design.

The morphological characters on different developmental phases of embryo and larva and the schedule of the whole early developmental process in Styela canopus were observed and described.The types of reproduction and early development as well as the morphology of egg and larva in different ascidian species were compared.Styela canopus is oviparous.Its egg,230.4~336.0 μm in diameter,is equipped with extraembryonic cell layers measured 43.2~63.0 μm thick.The early development of Styela canopus is typical urodele development,including fertilization,cleavage,gastrulation,tadpole in membrane,tadpole,initiating metamorphosis and juvenile.The tadpole of Styela canopus,with a length of 0.6~0.9 mm,consists of trunk and tail.There are obvious notochord,ocellus and adhesive papillae in the tadpole.Under the water temperature of(25±0.5)℃ and the salinity of 27.0,the larva was hatched after 9.5~11.0 h since the fertilization.

The regulation of three biogenic amines over the reproductive neuroendocrine activity of the male Scylla serrata was investigated by in vivo injection and in vitro incubation.The testicular index, the ratio of the mature sections in testes, and the ratio of Type B cells in androgenic gland were taken as the quantitative indexes.The in vivo injections indicated that:5-HT can significantly promote the testicular development and the secretion of the androgenic gland in S.serrata; DA can inhibit the testicular development, but no influence on the secretion of the androgenic gland was found; no significant difference was observed between the OA-injected group and the concurrent control group.In vitro incubations showed that:5-HT can stimulate the secretion of the brain and the thoracic ganglia, thus accelerating that of the androgenic gland; however, neither OA nor DA showed any significant influence on the secretion of the brain and the thoracic ganglionic mass.As to the optic ganglia, the three biogenic amines hardly have any effect on its secretion.It is the first time to report the regulation of biogenic amines over the reproductive neuroendocrine of male crustaceans through vitro experiments.Results corroborate that 5-HT activates the brain and the thoracic ganglia to secret GSH first, then promote the testicular development through the activity of the androgenic gland.

This paper discusses the origin and development of the Zhujiang Delta on the basis of the analyses of the fault systems, lithofacies, depositional thickness, ancient coastline and ¹⁴C dating.We consider that the delta is a multi-faulting block, whose external form, internal structure and configuration of its ancient coastline are all strictly controlled by three active sets of the NE, NW and WE faults.