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1.
3种沉水植物对水华藻类生长的影响   总被引:11,自引:0,他引:11  
Effects of three submerged macrophytes, Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum on the growth of bloom algae were investigated. The results of the coexistence assay indicated that, Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum inhibited significantly excessive growth of bloom algae. Of the three submerged macrophytes, Potamogeton crispus and Myriophyllum sp. have the stronger inhibition on bloom algae; at the relatively higher concentrations (Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum fresh weight 80,80 and 160 g/L), the aqueous extracts of fresh tissue of three submerged macrophytes can inhibit growth of bloom algae ; the growth of bloom algae was strongly inhibited by using dry powder; at the concentration of dry weight 20 g/L, the inhibitory effect by aqueous extracts of the dry powder of the three submerged macrophytes was beyond 50% ; the methanol extracts of the dry powder of three submerged macrophytes can inhibit growth of bloom algae at the relatively higher concentration.  相似文献   

2.
吴垠 《水产学报》2004,28(6):741-744
The effects of CO2 concentration on the growth and photosynthesis of Dicrateria zhang, jiangensis and Dunaliella sp, in 100 liter air lift photobioreactors were investigated. The results showed that biomass of both algae significantly increased in high CO2 concentration (above 700μL ? L^-1) compared to low CO2 concentration (350μL?L^-1) ,and the culture periods were shorter, However, no significant difference as observed in growth rate when the alga cultured in CO2 concentration of 700μL? L^-1 and 1000μL? L^-1, respectively. These for the maximum photosynthetic rate(Pm) and saturating irradiance level(Ik) of the two species remarkably raised with the elevated CO2 concentration, so was the initial slope(α)of Dunaliella sp.  相似文献   

3.
大西洋中部金枪鱼延绳钓渔场大眼金枪鱼的生物学特性   总被引:8,自引:3,他引:8  
宋利明 《水产学报》2004,28(2):216-220
Based on the biological data of bigeye tuna measured from the longlining ground of the Central Atlantic Ocean from Jun. 2001 to Oct. 2001, this paper analyzed the bigeye tuna‘s maturity stages of the gonad, feeding intensity, species composition of prey, sex ratio, fork length distribution, relationships between fork length and dressed weight, fork length and round weight, round weight and dressed weight by statistic and regression methods. The results indicate: ( 1 ) Maturity at Ⅳ-Ⅵ of the gonad are dominant with the highest percentage of Ⅴ (30.11% ). (2)The feeding intensity is mainly in the class 1 ,class 2 or class 3,totally 83.16%. (3)In the bigeye tuna‘s species composition of prey, the percentage of miscellaneous fish or cephalopod is relatively high, 38.05 % or 30.48 % respectively. Catch rate of bigeye tuna can be enhanced when cephalopod is used as the bait. (4) The male-female ratio is 2 : 1. This pattern might result from elevated mortality of adult females. (5) The fork length distribution is suitable for the normal. The dominant fork length is 1.13 - 1.49m, 64.16%, with the mean value of 1.32m. (6)The relationship between fork length and dressed weight. (7)The relationship between fork length and round weight. If the fork length is the same, the round weight converted in this paper‘s formula is a little lighter than the round weight converted in Parks‘s formula concluded at 1981 of the longline bigeye tuna catch. It might be caused by the different sampling areas or sampling time. (8)The relationship between round weight and dressed weight. The round weight conversion factor in this paper is a little higher than the ICCAT. It might be caused by the different processing methods. ICCAT is recommended to adapt this paper‘s conversion factor.  相似文献   

4.
鱼类热忍耐温度研究进展   总被引:25,自引:1,他引:25  
陈全震 《水产学报》2004,28(5):562-567
The paper is a review of the studies on the temperature of the thermal tolerance in fishes. It was described from four aspect: (1) The key parameters of temperature of thermal tolerance in fishes; (2) The influence factors of temperature of thermal tolerance in fishes; (3) The research methods of thermal effect of fishes; (4) The evaluation of effects of thermal pollution on fishes, especially, with the coastal power station will be‘built in China recent years, the effects of thermal discharge water on the marine fisheries resource wered iscussed.  相似文献   

5.
对虾免疫机能研究概况   总被引:16,自引:0,他引:16  
陈国福 《水产学报》2004,28(2):209-215
Shrimp farming is an important source of revenue and employment in many developing countries.However, infectious diseases have adversely affected the profitability of shrimp industry. For this reason, disease prevention is a priority and shrimp immunology has become a crucial research area of this field. In this paper, the current importance and problems of shrimp-culture were described and the research advances in shrimp immunological defence mechanisms were summarized. The immunological tools are powerful and useful to evaluate the health state of the shrimp. The immunologies of shrimp mainly consist of cellular immunity and humoral immunity. In regard to cellular parameters, they are composed of haemocyte count (THC), differential haemocyte count (DHC) and reactive oxygen intermediates (ROIs). The immunity ceils exert their defence functions through phagocytizing, enveloping, etc, and the changes of THC and DHC are related to health state of shrimp. The ROIs generated during post phagocytic event which maybe an important marker to evaluate the immunological capability and phenoloxidase activity have been considered as a potential marker which is relevant to the health of the shrimp too. Concerning humoral parameters, prophenoloxidase (ProPO) and phenoloxidase,antimicrobial peptides and proteins, hemagglutinin and plasma proteins were described. The determining methods of immunity parameters were discussed. The response of shrimp to pathogens such as bacteria, virus, etc. and environmental factors such as DO, pH, etc, were also reviewed. It is well-known that the immune responses induced by immunizing crustacean or shrimp are mainly the non-specific immune responses. The potential of immunological parameters, including the changes of THC and DHC, the production of ROIs, phenoloxidase (PO) activity, antibacterial activity of plasma, and so on, to appraise the healthy state of shrimp were partly discussed. The future directions for the evaluation of the immunological capability of shrimp were proposed.  相似文献   

6.
盐度对黄鲷胚胎发育及早期仔鱼生长的影响   总被引:16,自引:0,他引:16  
施兆鸿 《水产学报》2004,28(5):599-602
The effect of salinity on embryo and early larva development of Dentex tumiforns was discussed. Floating forms of egg in different salinities, optimal salinity for embryonic development and early larva growth was studied. The results showed: 1. In immobile condition, all eggs sank at salinity of 32.0, most of egg ssuspended in the middle of water at 34.0, and all eggs floated on the surface when salinity above 36.0. 2. Eggs did not hatch out at salinity of below 10.0 or above 60.0 and the death time of egg gradually moved up with increase or decline of salinity. Eggs hatched out at salinity range of 15.0 and 50.0, including abnormal larva. There was indistinct difference in speed of embryonic development (about 36-40h) within the salinity of 15.0 and 50.0. However the salinity had a great effect on larval survival after hatching and abnormal rate. The relation between hatching rate and salinity variation showed parabola but abnormal rate showed inverted parabola. The hatching rate was 81%-86% and abnormal rate of yolk sac larva was 27%-30% in suitable salinities of 27.0-39.0. The hatching rate was 89%-91% and abnormal rate was 13%-16% in optimal salinities of 33.0-36.0. The oil ball of abnormal larva was located in the central or front position. With increased extent of salinity, spondyle of larva bended and number of larva with arrhythmia increased. 3. The optimal salinities were 30.0-35.0 based on SAI. The test with SAI showed that SAI of early larvae was 41.25-47.53 at salinities of 30.0-35.0, the yolk and oil ball of 7-8 days larva was completely absorbed with a survival rate of 88%.  相似文献   

7.
大菱鲆胚胎的玻璃化冷冻保存   总被引:3,自引:0,他引:3  
田永胜 《水产学报》2005,29(2):275-280
Vitrification solutions were examined for their suitability of cryopreservation of turbot (Seophthulnms maximus) embryos. PMPI gave higher survival rate (75.68%) than other vitrification solutions and was considered to be suitable liar the cryopreservation of turbot embryos. The freezing point of the vitrification solutions consisted of PG and MeOH in the proportion of 3:2 was measured when the vitrification solutions were cryopreserved. It showed that the vitrification solutions with a cryoprotectant concentration of over 41% have no freezing point and the freezing points of vitrification solutions containing 33.33%-40% cryprotectants were between -32.4℃ and -65.4℃, The freezing point decreased with the increase of cryoprotectant concentration. The resistance of turbot embryos at different stages to the cryoprotectants was studied, It was found that the turbot embryos from 4-5 pairs somite to tail bud were more resistant to cryoprotectants and suitable to vitrify. A live embryo was obtained after cryopreservation in liquid nitrogen for 14h and was hatched out。  相似文献   

8.
水产养殖动物基因组研究的现状及其应用前景   总被引:3,自引:0,他引:3  
孙效文 《水产学报》2004,28(6):716-722
The genomic resources from human and several model organisms have been increased very fast since 1990. The techniques for developing genomic resources have already been very advanced and smart. These could make scientists see and improve organism in genomic level. For Chinese aquaculture scientists and aquatic industry, developing genomic resources and genetic tools for the native species are most important in the genomic era. The genomic resources and genetic tools for several aquatic species have been developed and some of them have been used in the marker based selection and other researches. The genome research work on aquaculture species was reviewed in this paper, especially a USDA genome project was focused. Some functional genomic research for aquatic animal was also discussed here. The importance and necessity of China aquaculture species genome project were discussed. Common carp and other cultured fishes in Cyprinidae such as grass carp, silver carp, bighead carp etc were recommended as the candidate species for genome research, because the output of all carps is almost up to 1/3 of total fisheries output in China. Common carp with another virtue for genome research is that there are much more families and strains in common carp than those in other cultured species in China, and those families and strains are the basis for genome research and mapping quantitative trait loci associated with important economic trait. Although the first linkage map of common carp made by Sun needs to be added with more markers for mapping QTL and Type I markers ,it has laid the groundwork for QTL mapping and markerassisted selection in common carp. Because the model organism zebrafish and common carp, grass carp and other carps cultured in China all belong to Cyprinidae, the China carp genome research will obtain a lot of useful information from zebrafish genome research. How the China carp genome program will be conducted and what kinds of strategy involved in this program were all suggested. How the results of the genome research of aquaculture species will be used in the aquaculture industry was reviewed and analyzed here.  相似文献   

9.
IntroductionThe China Sea is divided into four sea regions(Fig.1) :the Bohai Sea(BS) ,the Yellow Sea(YS) ,theEast China Sea(ECS) and South China Sea(SCS) .The Bohai Sea,the Yellow Sea and the shelf of the EastChina Sea together form a broad epicontinental Sea.The average depth of Bohai Sea is18m and that of Yellow Sea is4 4m.Together,the Bohai Sea and Yel-low Sea form a gulf opening to the ECS.A shallow trough runs through the gulf and can be traced south tothe northern end o…  相似文献   

10.
大菱鲆仔鱼皮肤发育及超微结构   总被引:1,自引:0,他引:1       下载免费PDF全文
朱杰 《水产学报》2003,27(2):97-104
The histological development and ultrastructure of larval turbot skin were studied by both light and transmission electron microscopes.The early larvae showed a complete bisymmetry of skin.The skin of 1-25days old larvae developed slowly and was composed of the thin epidermis of 1-2layers epidermal cells and undeveloped dermis before the metamorphosis.But the skin developed significantly when the.metamorphosis began.Till the completion of metamorphosis(about 60days old),the skin contained 3-4layers epidermal cells and very developed collagenous strata.Wisth the process of metamorphosis,the ocular side skin and blind side skin became different in ultrastructure.Ultrastructural observation showed the epidermis of turbot contained three types of epidermal cells;filament-containing cells,mucus cells and chloride cells.The ocular side epidermis with looser structure consisted one type of filament-containing cells,but the blind side epidermis was structured densely and two types of filament-containing cells were observed in it.Melanophores,iridophores,fibroblasts and other cell types and tisssues were found in the spongiosum of dermis.The distribution of melanophores depended on the larval developing stage and the pigmentation of skin.The differentiation of skin seems to be an adaptation for the change of life style of turbot larvae from pelagic living to benthonic living after the metamorphosis.  相似文献   

11.
甲胺磷、辛硫磷对坛紫菜叶状体的生理效应   总被引:8,自引:0,他引:8  
李钦 《水产学报》2004,28(2):221-224
In this paper, the effects of methmidophos and phoxim with different concentrations and schedule on soluble protein content and chlorophyl a (Chla) content in Porphyra haintanensis were studied under experimental and ecological conditions. The results showed as follows: (1) there were some time-effect and dose-effect relationships between the pollutants and Chla contents. The Chla content of most of groups decreased with the increasing of dose and prolonging of the exposure time. In the same concentration, the toxicities of phoxim to Chla content was stronger than that of methmidophos. (2) All concentration groups in this study didn‘t show the significant time-effect and dose-effect relationships between pollutants and the soluble protein. And there was no significant difference of the soluble protein content among various groups.  相似文献   

12.
半滑舌鳎染色体核型分析   总被引:34,自引:6,他引:28  
周丽青 《水产学报》2005,29(3):417-419
The tonguefish Cynoglossus semilaevis (Giinther) is a rare fish species in Chinese offing, inhabiting in the warm water bottom. The metaphase chromosome preparation of the fries has been got from their fins by hot air drying methods, while the metaphase chromosomes of one year old young fish which has physiologically sex differentiation has teen got from their renal tissues by the method of PHA and colchicine injection. The karyotypes were examined. The result shows that there are 42 acrocentric chromosomes in diploid and their karyotype formula is 2n = 42t, and there existed heterotypic sex chromosome which belongs to ZW/ZZ type. The sex ratio in artificial bred stock is nearly 1 : 1.  相似文献   

13.
赤点石斑鱼神经坏死病毒外壳蛋白全基因克隆与序列分析   总被引:5,自引:1,他引:5  
黄剑南 《水产学报》2005,29(3):429-432
  相似文献   

14.
水产养殖     
040196在卤虫培养中用细菌益生素控制溶藻弧菌=Control of Vibrio alginolyticus in Artemia culture by treatment with bacterial probioticus[刊,英]/Villamil L,Figueras A,Planas M…∥Aquac..-2003,219(1/ 4).-43-56 为了测定6种乳酸菌(LAB)菌株,乳酸和LAB的主要细胞内产物(ECPs)对卤虫培养中细菌含量的影响,进行了2个试  相似文献   

15.
崔立 《畜禽业》1999,(9):15-17
The yeast cell wall is recovered as a by-product during the production of soluble extracts from brewer's yeast(Saccharomyces cerevisiae).It is made up predominantry of glucan,mannan oligsaccharides,glucoprotein and chitin polymers.The glucan is a homopolimer of glucose linked through β—(1→3)and β—(1→6) D glycosidic bonds.The therapeutic effect of glucan has been primarily due to stimulation of reticuloendothelial system(RES).Studies have demonnstrated the effect of glucan in improving host resistancee by enhancing immunty to certain malingant tumors as well as to certain bacterial and viral infections.MOS's acts in the gut of animal capturing hostile gut-wall-attacking bacterla like E.Coli.Cell wall can be applied in all sorts feeds,but it is especially recommended for weaning piglets and aquaculture feeds.  相似文献   

16.
基于模糊AHP的长寿湖生态系统健康评价   总被引:2,自引:0,他引:2  
Ecosystem health assessment is a focus and hot spots field of ecological research, there is no unified evaluation indicators and evaluation methods. First, according to the area physical, human features of the Changshou lake and existed research, We established ecosystem health evaluation system which has included three secondary indexes : the ecological characteristics indicators, the function indicators and the socio - economic indicators, and has 20 indicators. Second, we assess the Changshou lake ecosystem with the ecosystem health index which based on the fuzzy AHP. The conclusions are as follows: in 2006, the Changshou lake ecosystem health index was 0. 471, it is showed that the ecosystem is in sub health, the mainly reasons is its upper reaches of the Di- anjiang county, Liangping county long - term discharge of industrial sewage and pollution of fencing fish.  相似文献   

17.
The biological cleaning agent Pondplus was dowsed each ten days at different dosage into breeding ponds for Chinese mitten crab with stocking rate at 12 000 ind./ha, to evaluate its purification effects on water environment in breeding ponds and its effects on Chinese mitten crab growth. The results showed that dousing treatment improved the water quality significantly as evaluated according to the parameters of DO, CODMn, NH4 + - N and NO2 - -N. Particularly, when the air temperature was higher than 35℃, the diurnal observation on DO values at the bottom of ponds showed that dousing at 450 g/( ha•m) gave a DO value higher than 4 mg/L all day long, which was 2 mg/L higher than that of control. The observed increase of Chinese mitten crab were 14. 9% , 27.8% , 27.8% by average weight, when dousing at 150, 300, 450 g/(ha • m) , respectively. Accordingly, the production increased by 8.5%, 11.9%, 18.6% through its promotion of Chinese mitten crab growth, and the economic efficiency were enhanced by 96.2% , 159.8% , 180.9%.  相似文献   

18.
<正>The Journal of Resources and Ecology(JRE)is an international English language journal that was started in 2010.The journal is jointly sponsored by the Institute of Geographic Sciences andNatural Resources Research(IGSNRR).Chinese Academy of Sciences(CAS).the China Society of Natural Resources,and lhe Ecological Society of China.The Journal of Resources and Ecology's mission is to create a platform for the promotion of international academic exchange.The journal aims to provide a comprehensive representation of  相似文献   

19.
A visit to China in September1980 by the then Norwegian Prime Minister,Mr.Odvar Nordli,initiatedthe present cooperation between fisheries institutions in China and Norway. The Prime Minister's delegationwas informed about the programme for economic reconstruction of China,a programme that also included amodernization of the fishing sector. As a support to the open door policy and the new development,Norwayoffered to donate a fisheries research vessel to China.Such a vessel could be used …  相似文献   

20.
伴随着中国水产养殖业的快速发展,原产美国的旧金山卤虫(Artemia franciscana)被引入至我国渤海湾地区.为研究旧金山卤虫被引入中国后其基因组遗传多样性改变情况,本研究利用COI线粒体分子标记,评估旧金山卤虫在非原生栖息地,即唐山曹妃甸南堡镇(渤海湾,河北省)定殖的旧金山卤虫的遗传多样性现状.研究分析发现:...  相似文献   

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