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1.
观音阁水库位于辽宁省本溪县境内,坐落于太子河干流上,正常水位255.2米,流域面积2795km2,养鱼水面47.33km2,在水库养殖分类上属大型水库.最高水位时库水最深处约60米,库区最大长度为35km,为典型山谷型水库.水库多年平均封冻期约100天.大水面养殖通常是指利用水库、湖泊、江河等大型淡水水体养殖水产品的一种养殖方式.可分为集约化养殖和粗放型养殖两种模式.粗放型养殖模式又可分为增殖型和投放式两种养殖方式,如向水库投放大银鱼受精卵即为增殖型养殖,向水库投放鲢、鳙、青、草等四大家鱼鱼苗(种)即为投放式养殖.有时一种鱼类既有增殖型养殖又有投放式养殖,如向水库放流鲤、鲫鱼苗(种)等的养殖.为保护库区水质和渔业资源,观音阁水库所有水产品养殖全部采用粗放型养殖模式.即每年向水库中投放一定数量的各类鱼种或鱼卵,不投放任何饵料,利用水库内的天然饵料资源进行放牧式养殖.以下介绍观音阁水库粗放型养殖鲢、鳙等商品鱼各生产环节中的有关技术流程和操作方法.  相似文献   

2.
扬中四面环江 ,由五个不相连的小岛组成 ,总面积 332km2 ,江岸线 12 0余km。陆地面积 2 2 5km2 ,长江水域面积 10 4km2 ,江滩面积 16 6 7.5ha。由于江滩处于大江堤之外 ,长江潮汐带中间 ,具有重要的行洪泄洪和生态环保功能 :二十世纪八十年代以前 ,我市开始对江滩资源进行开发利用 ,但处于低水平开发阶段。八十年代初期 ,逐步加大了对江滩资源的开发力度。至今总计开发江滩面积 4 40 .2 2ha ,其中用于水产养殖面积为2 0 0 .1ha ,为稳定我市水产养殖面积 ,促进水产养殖业的结构调整 ,起到了不可替代的作用。为进一步挖掘江滩资源潜力 ,针对江滩资源的生态特点 ,结合以往开发方式的成功经验 ,借鉴湖泊大水面围栏养殖技术 ,我们设计出了一种“深挖塘、低筑埂、高围栏”的江滩新型开发方式。该方式在最大程度上保护了江滩原有的生态环境和功能 ,且工程投资小 ,效益高 ,生产出的水产品符合市场对食品安全的需求 ,为江滩资源的综合开发利用提供了一种可靠的途径。  相似文献   

3.
<正>乐亭县是河北省第一沿海大县,海岸线124.9km,潮间带面积310km2,浅海面积1 808km2,近海水质营养物质丰富,浮游生物含量很高,底栖生物种类繁多,鱼、虾、蟹、贝等主要海洋经济资源丰富,但随着工业产业不断向沿海聚集,工业废水、生活垃圾污染以及养殖废水的大量排入,致使浅海海域生态环境不断恶化,加之近些年对海洋渔业资源的过度捕捞,导致海洋生物资源  相似文献   

4.
骆马湖属典型的过水性湖泊,面积260 km2(水位23.0m),网箱网围养殖区26.7 km2,由于网箱养殖草鱼具有生长速度快、产量高、效益好、销路畅的特点,大多数网箱以养殖草鱼为主.现将湖泊网箱养殖草鱼技术介绍如下;  相似文献   

5.
<正>乐亭县海岸线长98km,滩涂贝类是本县水产 养殖的重要品种。主要有文蛤、青蛤、杂色蛤、毛 蚶、缢蛏、扇贝等。2004年全县贝类养殖面积达 到1万hm~2,总产量4400t。贝类养殖在乐亭县已 形成一定规模,但也面临一些问题。 乐亭县滩涂贝类养殖所面临的问题 1.1恶性采捕导致资源溃乏 乐亭县的贝类养  相似文献   

6.
骆马湖属典型的过水性湖泊,面积260 km2(水位23.0 m),网箱网围养殖区26.7 km2,近年来由于示范户的示范带动,沿湖渔民从事网箱养殖的积极性高涨,而且由于网箱养殖草鱼生长速度快、产量高、效益好、销路畅,大多以网箱养殖草鱼为主,尤以新沂市窑湾镇湖区最为突出.  相似文献   

7.
陈秀玲 《河北渔业》2007,(11):16-17
昌黎县是河北省沿海渔业经济大县,拥有52.1 km的海岸线,44 667 hm2的浅海资源及25 000 hm2的滩涂.多年来,随着渔业结构的战略性调整,昌黎县依托区域资源优势大力发展海水养殖业,逐步形成了以筏式扇贝为主的浅海养殖,以河豚鱼、车虾、海参为主的池塘养殖,以发展高档海水鱼为主的工厂化集约养殖以及水产品加工,销售等相关行业并举的渔业经济发展新格局.  相似文献   

8.
延津县渔场位于延津县北部,马庄乡驻地西偏北约6km,大沙河滩区南侧约2km,占地面积19.65hm2,一期规划养殖水面面积10.0hm2,渔场以培育"黄河鲤"苗种为主,兼顾商品鱼的生产,渔场于2010年开始建设,一期于2011年底建成并投产。场区位于河南省黄河以北重要的水产养殖基地腹地,但  相似文献   

9.
乐亭县是河北省沿海大县,海岸线长98.2km,滩涂、浅海面积4.3万hm2(65万亩).对虾养殖起步早、起点高,自80年代以来一直走在全国的前列,成为全国对虾养殖示范县和国内重要的对虾出口创汇基地.作为我县海水养殖的优势品种,对虾一直居县域海洋经济中主导地位.  相似文献   

10.
1 海洋生物资源 地球表面积为51 000万km2,其中海洋面积36 100万km2,占70.8%.我国内陆面积960万km2,而东、南、黄、渤海四个海区面积达480多万km2,占内陆面积的50%. 水产品含有丰富的蛋白质,且易为人体消化吸收,作为人类的蛋白源,几乎现成的包含着人体新陈代谢所必需的重要营养物质.  相似文献   

11.
The domestication of the dog took place in the late Glacial. Its earliest record comes from Oberkassel near Bonn and its age is some 14000 years B.C. On the other side the domestication of the farm animals began about 10000 years ago, during the so-called Neolithic Revolution, when man's way of life changed basicly from the hunter-and gatherer-culture to agriculture and animal husbandry. This change took place in the valleys and on the slopes of the mountains surrounding the basin of the Euphrat and Tigris rivers which is called the Fertile Crescent. Sheep and goat were succeeded by pig and cattle. Immediately after the transition to domestication with protection by human being taking the place of natural selection the livestock animals and the dog underwent a decrease in size. This reduction in size is one of the most important criteria for distinguishing prehistoric domestic livestock from their wild forms. In high developed cultures domestication resulted in a hardly imaginable morphological and physiological extension of variability, in a richness of forms not to be guessed by the whole potential of the corresponding ancestors. But all these rich appearing forms were due to intraspecific procedures. They don't create new species. By the way of the increasing influence of man and its domestic animals on the environment the procedure of domestication is more and more shifted in the foreground and increasingly intervenes with the interests of wild life.  相似文献   

12.
Spermatogenesis and its endocrine regulation   总被引:4,自引:2,他引:2  
Three major phases compose spermatogenesis: mitotic proliferation of spermatogonia, meiosis of spermatocytes, and spermiogenesis, the restructuring of spermatids into flagellated spermatozoa. The process is fuelled by stem cells that, when dividing, either self-renew or produce spermatogonia that are committed to proliferation, meiosis, and spermiogenesis. During all phases, germ cells are in close contact with and require the structural and functional support of Sertoli cells. In contrast to germ cells, these somatic cells express receptors for sex steroids and follicle-stimulating hormone (FSH), the most important hormones that regulate spermatogenesis. A typical Sertoli cell response to an endocrine stimulus would be to change the release of a growth factor that would then mediate the hormone's effect to the germ cells. Recent studies in the Japanese eel have shown, for example, that in the absence of gonadotropin Sertoli cells produce a growth factor (an orthologue of anti-Müllerian hormone) that restricts stem cell divisions to the self-renewal pathway; also estrogens stimulate stem cell renewal divisions but not spermatogonial proliferation. Gonadotropin or 11-ketotestosterone (11-KT) stimulation, however, induces spermatogonial proliferation, which is in part mimicked by another Sertoli cell-derived growth factor (activin B). Since FSH (besides luteinizing hormone, LH) stimulates steroidogenesis in fish, and since FSH is the only gonadotropin detected in the plasma of sexually immature salmonids, increased FSH signalling may be sufficient to initiate spermatogenesis by activating both Sertoli cell functions and 11-KT production. Another important androgen is testosterone (T), which seems to act via feedback mechanisms that can compromise FSH-dependent signalling or steroidogenesis. The testicular production of T and 11-KT therefore needs to be balanced adequately. Further research is required to elucidate in what way(s) 11-KT stimulates later stages of development, such as entry into meiosis and spermiogenesis. At this period, LH becomes increasingly important for the regulation of androgen production. Results from mammalian models suggest that during the later phases, the control of germ cell apoptosis via Sertoli cell factors is an important regulatory mechanism. In many species, sperm cells cannot fertilize eggs until having passed a maturation process known as capacitation, which includes the acquisition of motility. Progestins that are produced under the influence of LH appear to play an important role in this context, which involves the control of the composition of the seminal plasma (e.g., pH values). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
鱼类诺达病毒及其所导致的疾病   总被引:2,自引:1,他引:1  
黄剑南 《水产学报》2006,30(6):831-836
In recent years, piscine nodaviruses have emerged as major pathogens of a wide range of larval and juvenile marine finfish resulting in high mortality in aquaculture worldwide. Affected fish exhibit a range of neurological signs, such as erratic swimming behaviour with the associated microscopic lesions of necrosis and vacuolation of the central nervous tissues and retina. Numerous roundshaped, unenveloped and 25-30 nm in diameter virus particles were found in the cytoplasm of affected retinal and nerve cells. Nodaviruses have a bipartite genome of positivesense RNA,with RNA1 encoding the RNAdependent RNA polymerase and RNA2 encoding the capsid protein. Both RNA are capped, but not polyadenylated. The family Nodaviridae comprises two genera: Alphanodavirus and Betanodavirus, members of which primarily infect insects and fish, respectively. Therefore, betanodavirus is also named piscine nodavirus. At present, piscine nodaviruses are divided into four genotypes based on partial sequences of the coat protein gene. ELISA and RT-PCR amplification have been developed as specific diagnostic methods for the d etection of the virus. Antibodies to striped jack (Pseudocaranx dentex) nervous necrosis (SJNNV) were found in 65% of plasma samples collected from wild and domestic brood stocks of striped jack, suggesting that the virus is very prevalent. Viral antigens were detected in eggs, larvae, and ovaries of hatcheryreared and wild spawner fish, suggesting both horizontal and vertical modes of transmission of the virus. Selection of nodavirusfree spawners using ELISA for detection of antigens and RT-PCR techniques have successfully reduced incidences of the virus infections in juvenile sea bass (Dicentrarchus labrax),striped jack and barfin flounder (Verasper moseri). The SSN1 and GF cell lines have been successfully used in isolating piscinenodaviruses.Although there are many papers describing the molecular characteristics of betanodavirus, our knowledge of the genomic attributes of these viruses is still limited. Vaccination studies are being undertaken by a number of researchers and need to be fostered. In particular, the use of passive immunization of broodfish with homologous and heterologous, high titre antisera are worthy of investigation.  相似文献   

14.
为探究岛礁海域渔业资源群落格局,于2016年8月、12月及2017年2月和5月对马鞍列岛及其东部海域进行了渔业资源季度调查。利用聚类分析、非度量多维标度(nMDS)和生物环境相关分析(BIOENV)等方法,对该海域的鱼类群落组成、时空动态及其与环境因子的相关性进行了研究。共采集鱼类96种,隶属于12目47科77属,其中鲈形目占比最大,其生物量和丰度占比均超过50%。龙头鱼为全年优势种,春季优势种包括刺鲳、黑鳃梅童鱼和宽体舌鳎;夏季优势种为小黄鱼、带鱼和六丝矛尾虾虎鱼;秋季和冬季优势种相同,为棘头梅童鱼和凤鲚。聚类分析和nMDS结果显示,马鞍列岛及其东部海域鱼类群落可分为站位组I (岛礁周围站点为主)、站位组II (邻近岛礁站点为主)和站位组III (远离岛礁站点为主)。除春季站位组I与站位组III、站位组II与站位组III外,鱼类群落种类组成在各季节不同站位组之间皆存在显著差异。BIOENV分析显示,在底层水温、底层盐度和水深3个因素中,底层水温对鱼类群落影响最大。  相似文献   

15.
This brief review focuses on health and biological function as cornerstones of fish welfare. From the function-based point of view, good welfare is reflected in the ability of the animal to cope with infectious and non-infectious stressors, thereby maintaining homeostasis and good health, whereas stressful husbandry conditions and protracted suffering will lead to the loss of the coping ability and, thus, to impaired health. In the first part of the review, the physiological processes through which stressful husbandry conditions modulate health of farmed fish are examined. If fish are subjected to unfavourable husbandry conditions, the resulting disruption of internal homeostasis necessitates energy-demanding physiological adjustments (allostasis/acclimation). The ensuing energy drain leads to trade-offs with other energy-demanding processes such as the functioning of the primary epithelial barriers (gut, skin, gills) and the immune system. Understanding of the relation between husbandry conditions, allostatic responses and fish health provides the basis for the second theme developed in this review, the potential use of biological function and health parameters as operational welfare indicators (OWIs). Advantages of function- and health-related parameters are that they are relatively straightforward to recognize and to measure and are routinely monitored in most aquaculture units, thereby providing feasible tools to assess fish welfare under practical farming conditions. As the efforts to improve fish welfare and environmental sustainability lead to increasingly diverse solutions, in particular integrated production, it is imperative that we have objective OWIs to compare with other production forms, such as high-density aquaculture. However, to receive the necessary acceptance for legislation, more robust scientific backing of the health- and function-related OWIs is urgently needed.  相似文献   

16.
壳聚糖及其水产应用研究进展   总被引:1,自引:0,他引:1  
韩杰  孟军  于志 《水利渔业》2006,26(5):11-13
壳聚糖以其独特的理化性质及生物学功能在农业、医药、工业方面有着广阔的前景。对壳聚糖的来源、制备方法、结构及理化性质做了简要说明,着重介绍了其生物学功能以及在水产业中的应用状况,并指出其在应用中存在的问题,为壳聚糖今后在水产业中的应用提供更好的科学依据。  相似文献   

17.
Since 1977 varroatosis has spread over the whole Federal Republic of Germany. This mite infection of bees, which is very new in Europe, has already killed many swarms and could not be stopped by veterinary regulatory measures (notifiability, restricted movements, obligatory treatment). At present bee-keepers are trying to avoid losses by a number of biologic measures and medications. Such measures should be based on exact knowledge of the parasite and its behaviour in the bee population. The present knowledge of the parasite and of the methods of control is given.  相似文献   

18.
气单胞菌及其在水产中的危害   总被引:1,自引:0,他引:1  
气单胞菌是一种条件致病菌,随着水产养殖的发展,它所引起的疾病对水产养殖的发展有很大的阻碍。本文介绍了气单胞菌的分类、特性、致病机理等,对其在水产动物的致病及防治方法进行了阐述。  相似文献   

19.
20.
斑马鱼及其人工繁殖   总被引:5,自引:0,他引:5  
刘伟成  李明云 《水利渔业》2006,26(1):31-31,39
斑马鱼具有一定的观赏价值和较高的科研价值。就斑马鱼的生物学习性、人工繁殖、幼体培育以及常见病害的防治进行了详细的介绍。  相似文献   

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