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1.
Four primary zooplankton species in Taolinkou reservoir located at Qinglong fiver in Qinglong Manchu county in Hebei province were investigated from April 2007 to March 2008, and the zooplankton species and anniversary distribution were concluded. The results showed that in the investigating period 57 kinds of zooplankton were totally found with protozoa 16, rotifera 22, cladocera 12 and copepoda 7, the forms and the preponderant species were different in different months. The average quantity of zooplankton in each month was 185.90 ind./L. The maximum quantity appeared at the earlier autumn. The average quantity (513.60 ind./L) of all sampling stations raised to its peak in August. The quantity was increasing with the temperature in spring and summer, decreasing after September, and lowest in winter. The average biomass was 1.68 mg/L which was the same diversification as the average quantity.  相似文献   

2.
《齐鲁渔业》2013,(12):I0001-I0001
Preliminary Study on the Biological Characteristics of Asterias amurensis in the Coast of Qingdao Li Shu-yunetal. (1) Abstract The biological characteristics of Asterias amurensis collected from the coast of Qingdao Fushan Bay from June 2011 to May 2012 were studied. The results showed the dominant lengths are 50-70mm of the adult length and the maximum is 91.2% in January.  相似文献   

3.
《齐鲁渔业》2014,(11):I0001-I0001
Added bagasse and Bacillus sp. to Litopenaeus vannamei intensive culture tank, the treatment groups were treatment A(added Bacillus sp.), treatment B(added Bacillus sp. with crushing bagasse) and treatment C(added Bacillus sp. with crushing-steaming bagasse) respectively. To estimate the effect of addition of bagasse with Bacillus sp. on the culture environment and shrimp growth, the level of total ammonia nitrogen(TAN), nitrite nitrogen and nitrate nitrogen, total amount of bacteria in the water and shrimp growth were determined. The result suggested that the TAN concentration in treatment B and C were significantly lower than that in treatment A during the early stage of the culture(P〈0.05). The addition of bagasse with Bacillus sp. was contribute to the formation of bio-floccules. The concentration of bio-floccules in treatment B and Cwere 6.3-20 ml/L and 8.3-30 ml/L respectively, which were significantly higher than that in treatment A(2.7-8.3 ml/L) during the culture(P〈0.05).The average weight of shrimp in treatment B and C were 8.56±0.21g and 8.84±0.26g respectively, which were significantly bigger than that in treatment A(7.66±0.40g) when harvest(P〈0.05).  相似文献   

4.
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   

5.
Ichthyological survey in Lake Gehu was carried out from January to December 2008, The analysis of species composition and diversity were also done. Age-structure of Hypophthalmichthys molitrix ( Cuvier et Valenciennes), Aristichthys nobilis (Richardson) and Carassius auratus (Linnaeus) were investigated in the protected areas. 30 species of fishes belonging to 7 orders, 9 families were collected and identified. The results indicated that the dominant species were Pseudobrama sirnoni (Bleeker), Carassius auratus (Linnaeus), Aristichthys nobilis (Richardson) , et al. Average characters of biodiversity indicated that Margalef's index was 2.68, Shannon-Weiner diversity index H' and H"were 2.02 and 2.08, Pielou's index J'and J" were 2.02 and 2.08. The fishery community in Lake Gehu took on character of miniaturization. Age-structure of Hypophthalmichthys molitrix ( Cuvier et Valenciennes) , Aristichthys nobilis (Richardson) and Carassius auratus (Linnaeus) were reasonable. The protection effect was good. Finally, the fishery strategy for the lake has been put forward in view of the above results.  相似文献   

6.
我国赤潮频发现象分析与海藻栽培生物修复作用   总被引:11,自引:1,他引:11  
徐姗楠 《水产学报》2006,30(4):554-561
In this paper, the history, main events and present status of red tide (HAB, harmful algal blooms) along China coast in recent years were reviewed and presented. It showed that the HAB's frequency and scale, number of HAB spec ies, percentage of toxic HAB events and the degree of damages to marine environment and economy have sharply increased in China since 1960's. Eutrophication was key factor for high occurrence of red tide. In this paper, main causes of frequent HAB occurrence along China coast was discussed. Many factors might influence the occurrence of red tide, which included weather, climate, coastal current, tidal current, water temperature, salinity, hydrodynamic and nutrient conditions, trace metals and the variation of biological environment. Numerous evidences from all over the world revealed the linkage between the increases in nutrient loading and the occurrences of high biomass blooms. Eutrophication was one of the important causes that involved in high occurrence of HAB. The main sources of nutrients potentially stimulating HABs included terrestrial runoff, aquaculture selfpollution, atmospheric deposition, sea projects and other pollution events in the ocean. Studies showed that the input from land contaminations and the selfpollution of marine aquaculture accelerated eutrophication in coastal waters and were also important impact factors on red tide. Researches suggested that nutrient composition could affect the species composition of phytoplankton as well as the development of some HABs. The changes in nutrient supply ratios, primarily N∶P, often resulted in shifts in red tide species composition. The correlation between cysts and formation of HAB was discussed from the viewpoi nt of transformation of cyst and vegetative cell, the effects of trace elements and other organic substances on the occurrence of HAB were presented also. It indicated that the nutrient control could be an effective way to reduce the risk of red tide occurrence. Seaweed would play an important role for decreasing marine eutrophication. Among the different methods of red tide controlling studied, seaweed biomass has received much attention due to the cost saving, low sensitivity to environmental and impurity factors, the possible contaminant recovery from the biomaterial and its elevated adsorption capacity. Cultivated seaweeds have very high rates of productivity higher than that of seaweed in its natural habits and grow well in water bodies with higher nitrogen and other nutrients. Seaweeds are able to absorb large quantities of nitrogen, phosphorus and carbon dioxide, produce large quanti ties of oxygen, and have excellent effect on decreasing eutrophication. Large amounts of C, N and P are accumulated into seaweed tissues as they accumulate considerable biomass over a period of months or years depending on the cultivation season. When seaweeds are harvested, nutrients are removed from the sea area. An investigation was carried out for inorganic nitrogen and inorganic phosphorus concentration at Lusi Coast, Qidong County, Jiangsu Province in China, where there were about 270 hm2 for Porphyra yezoensis cultivation with eutrophic sea water in recent years. While during Porphyra yezoensis cultivation, from Sep 2003 to May 2004, the concentration of ammonium nitrogen declined form 0.511-0.778 mg·L-1 to 0.006-0.057 mg·L-1, nitrite nitrogen concentration declined from 0.010-0.040 mg·L-1 to 0.001-0.009 mg·L-1, and nitrate nitrogen concentration declined from 0.466-0.549 mg·L-1 to 0.286-0.0568 mg·L-1, the average concentration of inorganic phosphorus declined from 0.024 mg·L-1 to 0.019 mg·L-1. Furthermore, during five hours, the concentration of ammonium nitrogen in the seawater declined form 220.88 μmol·L-1 to 8.59 μmol·L-1 by cultivated Gracilaria lemanaiformis, and the concentration of ammonium nitrogen declined form 213.84 μmol·L-1 to zero by cultivated Enteromorpha clathrata. Other bioremediation mechanisms of seaweed inhibiting the red tide microalgae such as nutrients competition and allelopathic effects were also discussed.  相似文献   

7.
王会芳 《水产学报》2004,28(3):347-351
According to the salmon‘s(Oncorhynchus) biological character of return to its hatching river, adopting the method of transplant and releasing, 9839000 eyed eggs of the salmon were introduced (Oncorhynchu, keta, O.gorbuscha, O. kisutch, O. masou) from Japan, total 8409000 juvenile fish was hatched and cultivated for 11 years running from 1985 to 1996. total 127 returning and mature salmons were collected from 1987 to 1995. It proved that the salmon could exist in the Yellow Sea area and return to its releasing river.  相似文献   

8.
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   

9.
线纹尖塘鳢的形态生物学与核型   总被引:6,自引:0,他引:6  
陈永乐 《水产学报》2006,30(4):562-565
This paper reports the morphological character and karyotype of Oxyeleotris lineolatus. Oxyeleotris lineolatus is native in Australia and call ed sleepy cod. It belongs to Oxyeleotris, Eleotridae, Gobioidei, Perciformes in taxonomy. Recently, it was introduced to China and local people were not familiar with it. So we carried out this study. 30 individuals have been observed and some data were recorded. It has a large mouth that is in front and up. The mandible stands out and is longer than the up jaw. There are many rows of thin teeth in up and down jaws. The pelvie fins are located in chest and pectoral fins are large and fanlike. There are two dorsal fins. The tail fin is circular. Gill rakers are sparse and the number of gill rakers is 8-12+3-4. The gas bladder belongs to physoclistaus and its stomach is strong and I-like. The intestine is thick and short and no pyloric caecas. The length of the digestive path is 48.1%-80.3% of the length of body. Its liver has two lobes and the liver weight is 4.1%-7.2% of the body weight. The digestive organs characters are same as the trait of flesheater fish. Its scale belongs to ctenoid scale and its body surface shows several long lines. There is not lateral line in the body. The number of vertebra is 26-27 and it has 10-11 pairs rib. The number of diploid chromosome is 2n=46 and the karyotype formula is 2sm+8st+36t,NF=48. The relative length of chromosome is from 1.37% to 3.48% and it is continuity. No strange size chromosomes relation to sex was observed. The karyotype of Oxyeleotris lineolatus is similar to that of Oxyeletris marmoratus Bleeker from South East Asia and both of them belong to Oxyeleotri. It testifies the correctness of traditional classification on cytology.  相似文献   

10.
黄河干流中上游水生生物资源调查研究   总被引:19,自引:1,他引:18       下载免费PDF全文
In order to protect scientifically the fishery resources and eco-environment of Yellow River , nine investigatioins on hydrobios in the middle and upper reaches of main Yellow River had been carried out since 2002 according to The Standard for the investigation of inland fishery resources. The investigations showed the present status of the fishery resources in these reaches are as follows :87species (genera)and 8 phylum of phytoplankton,42 species and 6 phylum of zooplankton, 14 species(genera) of banthic organism , 5 species of hydroplant, 38 species of fish. A comparative analysis,With the results of "the Yellow River Fishery Resources Survey in 1982",shows that the general trend of the plankton is that the average biomass is getting apparently decreased, the aboriginal fishes are endangered intensifically, and there must be some problem of aquatic biological invasion in these reaches. A granual miniaturization of fishes in main Yellow River has been noticed. The authors proposed to carry out investigation and researches on hydrobios resources in main Yellow River , and develop plans to protect the fishery resources in yellow River, which will be an important basis for rehabilitation of the Yellow River waters and it's ecological environment, for the maintenance of biological diversity of Yellow River's waters. And this work will be of great significance for people's life and sustainable development of economics in Yellow River basin.  相似文献   

11.
为研究大连旅顺口典型养殖海区中浮游动物群落结构及其与环境因子的关系,于2019年1,4,7和10月在3个典型海区设置采样点,同步监测调查浮游动物种类组成、生物量及其水质,并对水环境因子与浮游动物群落进行了差异显著性分析、Pearson相关分析和典范对应分析(CCA).此次调查共发现浮游动物24种,桡足类种类最多,优势种...  相似文献   

12.
于2012年5月–2013年1月对流沙湾海区浮游动物进行了周年性的季度调查,共检出浮游动物41种、幼体17类,以桡足类居多(29种)。亚强次真哲水蚤(Subeucalanus subcrassus)、短尾类幼虫(Brachyuran larva)、长尾幼体(Macruran larva)在四季均有出现,并在3个季度中成为优势种。年均浮游动物丰度和生物量分别为48.12 ind./m3、13.43 mg/m3。扇贝主养区、鱼类网箱养殖区和珍珠贝养殖区的各季浮游动物丰度及生物量均低于对照区(非养殖区);大中型浮游动物主要出现在对照区,而在鱼、贝养殖区极少出现。冬季扇贝主养区多样性指数为各区最高,其浮游动物丰度、生物量迅速回升,高于鱼类网箱养殖区和珍珠贝养殖区,但仍低于对照区。研究结果显示,鱼、贝养殖区域流沙湾海区的浮游动物丰度及生物量比往年明显减小,浮游动物的小型化加剧。  相似文献   

13.
獐子岛近岸人工鱼礁区浮游动物群落结构特征   总被引:1,自引:0,他引:1  
为研究獐子岛近岸人工鱼礁区浮游动物群落结构特征,利用2014年6月、10月和2015年6月、10月獐子岛近岸人工鱼礁区4个航次的调查资料,对该礁区浮游动物的物种种类、密度、生物量、多样性指数、与环境因子的关系等方面进行分析。调查结果表明,共发现29种浮游动物(包括6类浮游幼虫),2014年6月16种,2014年10月12种,2015年6月28种,2015年10月24种;优势种9种(包括浮游幼虫4种),拟长腹剑水蚤、中华哲水蚤、桡足类六肢幼体为4个航次共同优势种;浮游动物生物量和密度分布情况基本一致,最高值出现在2015年6月份的站位2,节肢动物门生物量和密度占绝对优势;聚类分析中2014年6月、10月和2015年6月浮游动物群落均分为4个聚类组,2015年10月分为3个聚类组;水温和盐度是影响浮游动物群落关系十分重要的环境因子,与浮游动物密度和生物量呈显著相关关系。  相似文献   

14.
为了探明陵水湾浮游动物饵料情况,本研究依据2014年11月(秋季)、2015年5月(春季)、8月(夏季)和2016年1月(冬季)陵水湾4个航次的调查资料,分析了该海湾浮游动物的种类组成、优势种、丰度和生物量、生物多样性等群落结构特征及其影响因素。调查共发现浮游动物94种和浮游幼虫21类,其中桡足类(Copepoda)最多,有38种,其次是水螅水母类(Hydromedusae)11种,毛颚类(Chaetognatha)8种,其余类群种类数在1~6种之间。浮游动物群落主要由广温广盐类群、暖水沿岸类群和暖水外海类群组成,优势种主要分布在前两个类群,无全年优势种;浮游幼虫是陵水湾的重要类群,丰度呈现为冬季(低温)高于春季(高温)。与亚热带海域不同,低温已不再是制约陵水湾海洋生物生长的主要因子。浮游动物丰度和生物量均呈现为秋季最高,春季最低,冬季高于夏季。浮游动物群落物种Shannon-Wiener指数(H¢)和均匀度指数(J¢)的变化趋势一致,表现为春夏季高,秋冬季低,湾外高,湾内低。聚类分析结果表明,陵水湾浮游动物可分为湾内和湾外两个群落,主要受地形阻隔所致。盐度与浮游动物丰度和生物量均呈显著负相关关系,是浮游动物季节变化的主要影响因子之一。根据陵水湾浮游动物年均生物量估算出浮游动物提供的渔产潜力为2.24×10~4 kg。陵水湾浮游动物丰度呈现剧烈的季节变化,有必要对其进行长期的跟踪监测。  相似文献   

15.
利用2011年5月?2012年4月(除冰期12月和翌年1?2月外)在渤海莱州湾逐月由底至表垂直拖网(网孔目160 µm)获得的浮游动物样品,开展小拟哲水蚤丰度分布周年季节变动研究。结果显示,小拟哲水蚤季节变化呈单峰型,7?10月份丰度较高,高峰值出现在8月份;水平分布以湾中部偏东侧丰度较集中,其次为湾口站位,湾顶站位为相对低值区。应用Primer 6.0软件中的BIOENV程序分析发现,小拟哲水蚤总丰度的月变化主要受水温影响、特别是1月前的水温,可能还受黄河径流量的间接影响;水平分布则与盐度、水深关系密切。  相似文献   

16.
2012年大神堂贝类养殖区浮游生物的群落结构   总被引:1,自引:0,他引:1  
为了解天津大神堂贝类养殖区的水生态环境,于2012年4-10月对养殖区5个站位的浮游生物进行了逐月调查。结果表明,该海域浮游植物共有3门、19属、22种,其中硅藻门占绝对优势,平均丰度为6.22×104个/L;浮游动物共2门、6属、6种,平均丰度为127.8个/L。各季节各站位的浮游植物多样性指数和均匀度指数分别为0.07~2.37和0.04~0.66,浮游动物多样性指数和均匀度指数为0.40~1.71和0.25~0.91。总体评价大神堂贝类养殖区浮游生物的多样性水平较低。  相似文献   

17.
An experiment was conducted for 80 days at La Salada de Monasterio Lake (Buenos Aires, Argentina) to assess the effect of stocking density and natural food availability on the growth and production of zooplanktivorous juveniles of pejerrey (Odontesthes bonariensis) in extensive cage culture. Ten cages were installed and stocked with 33‐day‐old fish, at three density treatments: 25, 50 and 75 ind. m?3. Zooplankton was analysed in terms of abundance, biomass and diversity considering three size classes. Caged pejerrey diet was assessed regularly. The pejerrey gut contents composition was clearly different from cage zooplankton, showing a trend to contain bigger components. Reared fish exhibited a tendency to diversification of the diet and to change the mean prey size depending on fish length and stocking density. Regression models showed a positive and direct effect of the bigger zooplankton biomass on fish growth rates, which were also inversely affected by the availability of smaller zooplankton. The results demonstrate that stocking density and available zooplankton, in both quantity and quality, are key factors in regulating extensive cage culture of pejerrey. Handling stocking densities in a dynamic way it is possible to maximize fish growth, biomass harvest or fish number according to the goals of production.  相似文献   

18.
福建东山湾浮游动物的种类组成与数量分布特点   总被引:6,自引:0,他引:6  
本文分析了2007年3月~11月于东山湾采集的浮游动物样品。结果表明,东山湾已鉴定的浮游动物有84种,其中水母类26种,桡足类37种,其它还有多毛类、介形类、枝角类、端足类和被囊类等以及阶段性浮游幼虫和少量的仔稚鱼,分为5个生态类群,以沿岸暖水类群和半咸水类群为主。浮游动物的种类数、总个体数和生物量的平面分布趋势大体相似,即湾口大于湾内,东部大于西部。总个体数与生物量的周年变化趋势非常相似,高峰出现在高温季节的8月,低谷出现在5月。调查期间东山湾浮游动物较为丰富,年均总个体数达982.3ind/m^3,生物量达163.2mg/m^3。与历史资料对比表明,东山湾的浮游动物物种多样性趋向减少,表现出优势种品种简单化而数量密集的倾向,这可能与湾内污染增加及环境变化有关,而生物量的增加可能与全球气候变暖及营养盐的增加有关。另外还对浮游动物的分布与环境因子的关系进行了分析。  相似文献   

19.
ABSTRACT:   The feeding habits of Lampanyctus jordani , an abundant mesopelagic fish in the subarctic North Pacific, was examined based on the stomach contents of 721 specimens collected over the continental slope off the Tohoku area, Pacific coast of northern Japan during April and October from 1996 to 1998. The prey items comprised mainly crustaceans such as copepods, amphipods, euphausiids and decapods. Euphausiids were the most important items in the diet both during April and October. During April, when the annual maximum of zooplankton biomass occurred and the Oyashio Intrusion Current prevailed, L. jordani fed intensively and consumed a high proportion of Euphausia pacifica . These seasonal variations also influenced the feeding intensity and dietary diversity. Feeding intensity, measured by the stomach contents index, was higher during April than October, reflecting the higher biomass of zooplankton in the Tohoku area during spring. The dietary diversity of L. jordani was lower during April than October, indicating that L. jordani shifted to a wider variety of prey when the availability of E. pacifica was limited.  相似文献   

20.
To date, little is known about the larval‐fish assemblages (LFAs) in the eastern Mediterranean. The purpose of this study is to investigate the intra‐annual variations of LFAs with an emphasis on the effects of physical, chemical, biological and meteorological conditions in the gulf of Iskenderun, which is a shallow (100 m maximum depth), semi‐enclosed bay located in the northeastern corner of the Mediterranean. The gulf is under the influence of offshore waters throughout the year. The study was based on an ichthyoplankton survey program performed at 28 stations over 12 months, between November 2009 and October 2010. During the study, a total of 11,411 larval individuals belonging to 177 taxa were sampled. The jackknife estimate of maximum species richness was 225 ± 19 for the study area. The maximum larval richness (84 species) and abundance (827 larvae/10 m2) values coincided with spring bloom in April. Gobiids dominated the ichthyoplankton of Iskenderun Bay by constituting 9% of species richness and 42% of total individuals. Four LFAs were identified which were in early winter (November to January), late winter (February and March), spring (April to June) and summer (July to October). The intra‐annual variations of richness, abundance and composition of ichthyoplankton were significantly correlated with the temperature and mesozooplankton biomass. The wind conditions and thermal stratification were also significantly correlated with the composition of LFAs. In conclusion, phenology of LFAs were formed under the influence of physical and tropho‐dynamic conditions in Iskenderun Bay, Northeastern Mediterranean.  相似文献   

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