Abstract:The effect of LHRH-A (des-Gly¹⁰, D-Ala⁶ LHRH-ethylamide) incombination with dopamine antagonist PIM or catecholamine depletor RES on gonado-trophin secretion and ovulation of the cultured fishes were investigated. Injection of themixture of LIIRH-A and PIM or LHRH-A and RES is highly effective in stimulatinggonadotrophin secretion and inducing ovulation or spawning of freshwater culturedfishes. The rates of spawning in our experiment were: black carp (Mylopharyngodonpiceus) 80%; silver carp (Hypophthalmichthys molitrix) 84%; bighead carp (Aristi-chthys nobilis) and grass carp (Ctenopharyngodon idellus) 88%; bream (Parabramispekinensis) 94%; and mud carp (Cirrhinus molitorella) 96%. The advantages of theseovulatory agents are high rate of ovulation, complete replacement of carp pituitary;beneficial to the protection of brooders as well as labour saving and low cost.

Abstract:According to the trial fishing practice in the deeper waters of the EastChina Sea and depending upon the installation conditions of our available purse seiners.a type of purse seine for operating in deepers waters was designed in recent years. Thenet sinking speed and net sunk depth of the purse seining method were tested andanalyzed in the cases of various current speed, unequal length and different haulingspeed of pursing cable, so that the relationship of these three varibles to net perfor-mance was obtained. The results are summerized as follows: 1) It is different to measure the natural sinking speed of the three parts of netbody. As for the comparison of their speed, the hauling end of net is at the first, themid-part of net is the second, and the bunt is the third. The natural sink of all partsof the net body appears as fast-slow-fast irregularity. 2) During the full period of operation, the fast current speed and the quickhauling of pursing cable are more disadvantageous for net sinking, while the longerpursing cable is more advantageous for the same one. In certain speed range, thehauling speed of pursing cable plays a main role in the sinking performance of the net.

Abstract:The mechnical analysis was made to two types of structure modelsof oblique and plane seams pitched with rectangular slab stones, in regard to the condi-tions of waves and water flows, thus the basic mechanical equilibrium relationship ofcritical stability of stones was obtained. On the basis of 40 varied structure sectionmodels and 1,380 times of wave model test was then made non-dimension analysis ofrelevant factors which may affact the thickness of pitched stones. As a result, thecalculation formula for determing the thickness of building pitching stones were putforward, which may provide a theoretical framework for engineering design of break-waters. Besides, some experimental results about the standard for breakwater design aswell as some analytic ideas were also provided in this paper.

Abstract:The ecological pattern, distribution and diversity of species of zooplankton in Changjiang Estuary and Hangzhou Bay were investigated and analyzed.On this basis, the impact of pollution on the zooplankton was discussed. It was discoveredthat the hemi-saline estuarine species, low salinity neretic species and temperate offshorespecies were dominating zooplanktons in the investigated areas. In accordance with thecomposition and morphology of the zooplanktons, it is still uncertain whether or notthe extent of the pollutants affected the species. However, the biomass of zooplanktonconsiderably decreased and a large amount of copper and zinc was accumlated in theplanktonic crustacean. Moreover, there occurred two times of red tide which wererespectively more than 30km² and 10 km² during the period of investigation. There-fore we should pay more attention to all these phenomena.

Abstract:The monthly 1ength-frequency data of Collichthys lucidus collectedduring 1986 in Pearl River Estuary was analysed by applying the ELEFAN Ⅰand Ⅱtechnique (Pauly et al., 1981). The growth parameters were estimated to be K=1.8,L_∞=171mm and t₀=-0.12, and the approximate longevity to be 1.5 years. A length-converted catch curve was then constructed, from which total mortality, Z=7.36,and mean sclection length, L_c=82mm, were calculated. Natural mortality, M=2.68,was estimated by using the empirical relationship between M, the growth parametersand mean environmental temperature (Pauly, 1980), and the exploitation rate, E= F/Z=0.636, was then obtained. Yield-per-recruit analysis and the value of yield-per-recruit analysis indicatedthat the stock of Collichthys lucidus in Pearl River Estuary is moderatly exploited.An increase in yield-per-recruit and the value of yield-per-recruit may be expected ifthe size of first capture have a moderate increase. However, no significant increase inyield-per-recruit and value of yield-per-recruit could be expected from regulating offishing mortality. This analysis also provided the optimin management alternative forthe short-lived fishes in the tropical waters. A recruitment pattern in the Collichthy lucidus stock was derived when using theELEFAN Ⅱ technique, and its appropriateness was discussed.

Abstract:The experiment conducted in the river of the east suburbs of Suzhourevealed that the water hyacinth had strong ability to accumulate heavy metals andpurity the waste-water. It could considerably reduce the concentration of the heavymetals in the water, reducing the Phenol from 0.005～0.023 mgL^-3 to trace, TN from5.330 to 2.330 mgL^-1, TP 0.840 to 0.183 mgL^-1, COD 54.80 to 29.36 mgL^-1; Cu 0.57to 0.32 ppb, Pb 0.14 to 0.06 ppb, Zn 65.6 to 23.6 ppb and Cd 0.14 to 0.03 ppb, ect.Meamwhile it improved water greatly, increasing the water transparency from 36.7 to90cm. Therefore, the river water after treated by water hyacinth could reach thestandard water quality suitable for fishes. According to the experimental results, thereis no distinct second accumlation of the heavy metals in the fish bodies after the fisheshave been fed on the water hyacinth. In the fish meat the contents of the heavy metalswere lower than the healthy food standard (Hg 0.3 mgKg^-1, As 1 mgKg^-1, Pb2 mgKg^-1.

Abstract:The purpose of this experiment is to study the effect of the alkali treat-ment on the yield and properties of agar extracted from Chinese Gracilaria and toselect the suitable species of Gracilaria as raw materials for the production of agar.Specimens of Gracilaria were treated with 32% NaOH at room temperature for 5 days.Using this cold concentrated alkali method, 10 species of Gracilaria which were collectedin China were studied. The agar yield, properties and chemical composition before andafter alkali treatment are shown in table 1, and the infrared spectra are shown in figs1,2 and 3. The main results obtained are summarized as follows: 1) Agars extracted with sodium hexametaphsphate afterr alkali treatment were muchbetter than those extracted with water. The agar yield from G. asitica was 27.6-31.3%, G. tenuistipitata was 14.0-39.5%, G. sjoestedtii 22.4-27.8%, G. haina-nensis 8.6%, G. articulata 19.1% G. chorda 15.4% G, textorii 21.6%, G.euche-umoides 31.7%, G. blodgettii 27.6% and G. sp.42.6%, respectively. 2) The Gel strength of agar extracted with (NaPO₃)₂ after alkali treatment were:G. asiatica 234-1025g/cm², G. tenuistipitata 329-1035g/cm², G. sjoestedtii 375-855 g/cm², G. hainanensis 130 g/cm~2, G. articulata 87g/cm~2, G. chorda 376g/cm~2,G. textorii 10g/cm², G. eucheumoides 38 g/cm², G. blodgettii 323 g/cm~2 and G. sp.923 g/cm~2. 3) According to the results of agar yield and gel strength, G. asiatica, G. tenuistipitata and G. sjoestedtii are considered to be the better raw materials for agarproduction to other species of Gracilaria ever studied. 4) The gelation and melting temperature of agar after being treated by alkaliwere increased while the viscosity decreased. 5) The 3,6-AG content of agar isolated. from alkali-treated Gracilaria was higherthan those without alkali treatment, and the reverse relation was observed about thesulfate and galactose content. The increase of gel strength lay in the extent of thesulfate decreased and the 3,6-AG increased. 6) The effect of the alkali treatment on the gel strength of Gracilaria agarvaried with the species of Gracilaria as well as the season and location they were collected. 7) The time of gel strength increased by the cold concentrated alkali method was34.4 on the average, thus cold concentrated for method appears to be more effective.than any other alkali treatment method reported.

Abstract:上海水产大学王素娼教授主编的《中国经济海藻超微结构的研究》一书即将由浙江科学技术出版社出版。全书的主体由120版约360幅图片和约12万字的文字论述组成。该书中研究的对象主要分三类:第一类为中国主要的养殖种类如海带、紫莱、裙带菜、江蓠、石花菜;第二类为经济海藻或者是中国特产的种类,如鹿角菜等;第三类为常见种或引进种类。

Abstract:This paper describes the larval development of Expalernon carinaica-udrx. This species distributes widely in the coastal provinces of China，and it is comzner-cial importance in the Locality. The prawn lives in the most part of estuaxies anal shallow sea.Under 22℃ it takes about 12 days for larvae to accomplish their metamorphosis to postlarval stage. The whole process of larval development may be divided.into sig zoeal stages.

Abstract:关于硬骨鱼类的嗅、味感觉器官在解剖学和生理学方面的研究成果,许多学者都发表过综述文章(Kleerekoper 1969,Bardach和Atema 1971,Bardach和Villars 1974,Kapoor等1975,Brown和Hara1982,Tucker 1983),最近十几年,对于鱼类化学感觉的电生理研究,主要在于一些天然物质、氨基酸及其衍生物对于嗅、味觉系统的相对刺激效果,刺激物的分子结构与刺激效果的关系,以及刺激物与感受细胞膜上的感受点相互作用的机制,而对于人为因素如捕捞、环境因素pH、污染对鱼类嗅、味觉的影响报导甚少(Hara 1976,1978,Konishi等1969,Tucker 1973,Silver,1978,Cancolon 1980,Hidaka 1970)。

Abstract:卡拉胶广泛地应用于食品、医药、日用化工和纺织等方面,而卡拉胶的成份和结构对它的物理性质有较大的影响,因此海藻多糖的组成和结构的快速分析在实际生产上有重大意义。目前公认利用¹³C-NMR谱图对海藻多糖成份和结构的分析是既方便又快速的有效测定方法。利用¹³C-NMR谱图对多糖进行结构分析一般需要预先制备一些模型化合物（Model Commpound）,再把模型化合物的¹³C-NMR谱图与结构未知多糖的¹³C-NMR谱图进行分析、比较,从而确定多糖的结构。

Abstract:Few empirical formulas have been proposed by means of mathematical inductionmethod, in accordance with the data from the weight and the center of gravity of about30 small fishing boats. These formulas can be used as ready reference for calculating displacement in apreliminary design.