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Based upon analysis of the seasonal fluctuation of GSI (gonado-somatic index), the spawning period of the hairtail extends from April to October. The maximum time difference between the early and the late brood individuals is about half a year. It is possible to distinguish the early brood and the late brood on the basis of the diameter of the first ring, setting 1.32 mm as a border line. Therefore, the identification of the first ring was solved in dispute. The maturation stages can be identified on the basis of the macroscopical and microscopical characteristics of the ovary; i.e., immature (II-A, B), maturing (III-C, D, E, IV-F), mature (IV-G, V-H, VI-I) and recovering (VII-J). Maturation is completed in the course of one year from different brood seasons. The smallest size at first maturity in female was about 170–180 mm in length and 80–100 grams in weight. There were two discrete groups in autumn which shown the same population unit in which those individuals may separate temporarily into different groups of biological activities in certain period of their life. Fishing of hairtail has been greatly intensified, the population structure has been subject to a series of change. But the hairtail has relatively strong adaptability, so that its population can maintain a reasonable size despite the heavy fishing.

A cruise through the western sea area of the Taiwan Strait was carried out by the R/VDong Fang Hong in December, 1987. Eight anchored and 10 not anchored stations were set up. Over 25 time-series current observations were made at each station and CTD (Conductivity-temperature-depth) measurements were made at 5 anchored and 10 not anchored stations. Based on the measured data. fine-structures and step-like vertical structures of temperature and salinity were analysed and a tentative wintertime current structure in the Taiwan Strait was described.

The velocity structure of the residual current across an entire section of the Qiongzhou Strait (QS) in summer is presented for the first time. Shipboard Acoustic Doppler Current Profile measurements, from the mid-region of the QS (110.18°E), were collected on 1–4 August 2010. The diurnal tidal currents had their maximum amplitudes between 4.24 and 20.24 m. Their amplitude along the major axis ranged from approximately 0.55 m/s in the middle part of the strait (20.15°N) to 0.84 m/s in the north part of the strait (20.20°N). Both anticlockwise and clockwise tidal current rotations exist in the QS. During the observation period (neap tide), a significant westward residual current occupied almost the entire study section. Two velocity cores of westward current were observed at the northern part and near the deepest trough, although an eastward current appeared in the middle part of the transect. The deepest core was located near 62 m at 20.13°N, with a maximum velocity of −0.34 m/s. The shallower core was located at approximately 16 m at 20.20°N, with a maximum velocity of −0.33 m/s. The estimated total volume of water transported through the QS was −0.16 Sv. This value is an important boundary condition, applicable to numerical models studying coastal ocean circulation in the northwestern South China Sea.

Bacterioplankton play key roles in the biogeochemical cycle and in organic contaminant degradation. The species richness and abundance of bacterial subgroups are generally distinct from each other, and this is attributed to their different functions in aquatic ecosystems. The spatiotemporal variations of eight phylogenetic subgroups (Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, Planctomycetes, alpha-, beta-, and gamma-Proteobacteria) derived from Donghu Lake were investigated using PCR-DGGE fingerprinting, to explore their responses to environmental factors. Results indicate that Actinobacteria and beta-Proteobacteria were the two largest bacterial subgroups detected. These two groups and Bacteroidetes showed clear seasonal patterns in composition of the operational taxonomic unit. Results also suggest that the bacterioplankton subgroups in Donghu Lake were significantly correlated with different environmental factors. In brief, the total nitrogen was one of the major factors regulating all the bacterioplankton except for Actinobacteria. However, total phosphorus, another important eutrophication factor, contributed to the two largest bacterial groups (Actinobacteria and beta-Proteobacteria), as well as to the Cyanobacteria and Firmicutes. Therefore, the responses of bacterioplankton subgroups to environmental factors were different, and this should be attributed to the differences in the functions of different groups.

Using a “three parameters” bottom model, the average sound intensity in homogeneous shallow water with constant depth is found by a better expression to be finite for normal mode number of water layer. The space structure of the sound field and some factors controlling the near, middle and far fields are discussed with this expression.

Ventilation or water exchange between the subtropical and tropic Pacific is studied with a simple none-thermodynamic two-and-half layer model. The shallow upper layer is assumed to communicate with its lower counterpart by entrainment and detrainment at ratesW e andW d. Trenberth wind stress data (Trenberth Data Center, 1995) are chosen to drive the upper moving ocean to obtain a stable state. The results show that the subtropical and tropic Pacific exchange water in two ways. One is the direct exchanging by which the surface water in the mid-latitude goes down and moves to the tropical region in the subsurface layer and upwells back to the Ekman layer and finally moves northward to complete its journey; and the other is the way of detour, by which water in the subtropical Pacific moves first to the western boundary region along geostrophic flow contours and goes down to the tropic region as southward boundary currents. These two ways contribute almost the same amount to the water exchange between the subtropical and tropic Pacific gyres although the spatial scale in the latter is ten times greater than that of the former. LPS's (Luyten et al., 1983) ventilation theory is reviewed to give a clear picture of how the water exchange in large scale has been studied and the numerical results in this paper are compared with both the conclusions of such analysis theory and some previous observation (tritium survey) reports.

The morphology and infraciliature of a marine ciliateAnphileptus litonotiformis nov. sp. inhabiting a shrimp farming pond in Sheyang (Jiangsu Province) are described. According to the infraciliature, habitat, and other morphological characters, it can not be congeneric with any other species of the genus. The special features ofA. litonotiformis are theLitonotus-like body shape and the arrangement of its extrusomes regularly located along the margin of the cytostome. The most important characters of some relatedAnphileptus-species from marine water are biometrically tabled and discussed.

The marine macroalgae Enteromorpha prolifera was one of the main algal genera that occurred in the widespread green tides in Qingdao, China, during the summers of 2007, 2008 and 2010. It is thus a plentiful source of biomass and could be used as a biofuel. In this study, the pyrolytic characteristics and kinetics of E. prolifera were investigated using thermogravimetric analysis (TGA) method. Cornstalk and sawdust were used as comparisons. Pyrolytic characteristics were studied using TG-DTG (thermogravimetry-derivative thermogravimetry) curves. Three stages in the pyrolytic process were determined: dehydration, dramatic weight loss and slow weight loss. E. prolifera was pyrolyzed at a lower initial temperature than the two terrestrial biomass forms. The apparent activation energy values for the three types of biomass were calculated and the mechanism functions were determined using 16 different mechanism functions, frequently used in thermal kinetics analysis. Activation energy values varied with mechanism function and the range of activation energy values for E. prolifera, cornstalk, and sawdust were 25–50 kJ/mol, 60–90 kJ/mol and 120–155 kJ/mol, respectively. This indicates that E. prolifera has low thermal stability for pyrolysis and good combustion characteristics.