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1.
《水产科技情报》1975,(5):F002-F003
通过无产阶级文化大革命,水产战线上的广大职工在毛主席革命路线的指引下,深入调查研究,掌握了河蟹的生活史,并在长江口区一带发展了蟹苗生产,取得了显着成绩,为增殖我国内陆水域里的河蟹资源开辟了新的途径。  相似文献   

2.
王宇庭 《水利渔业》2005,25(6):71-73
我国作为发展中国家,放养渔业是内陆渔业的主要方式,如何操纵鱼类实现渔业和水环境保护的协调发展,是实现水库、湖泊渔业健康发展的关键问题.总结了放养渔业与富营养化关系的研究成果,分析了上、下行影响之间的关系,认为放养渔业能够抑制水体的富营养化,但其抑制的程度和范围是有限的.为发挥放养渔业在富营养化抑制方面的更大作用,需要结合不同营养状态和水文特征对放养组合、放养规模以及水草的合理存在空间进行更深入的研究.  相似文献   

3.
中国水产学会水产捕捞专业委员会和安徽省水产学会于1987年4月24-28日在黄山市联合召开了首届“全国内陆水域捕捞技术讨论会”,23名代表参加了会议。会议征集到科学论文和科技报告共18篇,宣读了15篇,其中多数为近年来生产性课题的总结,包括:池塘底层鱼捕鱼技术。  相似文献   

4.
养殖河蟹者要求是获得较高的商品效率,也就是说一要蟹的成熟度高,二要回捕率高,这就取决于捕蟹技术了。总结众多生产者的经验可归结为两点:一是确定较佳捕捞时间;二是捕捞工具与方法。养殖河蟹的较佳捕捞时间是在河蟹完成生殖脱壳后,一般湖泊放养的长江蟹,宜于9月中下旬开捕,而  相似文献   

5.
苏联内陆水域水面辽阔,全国计有湖泊285万个,面积近6,000万公顷,其中有近2,500万公顷有渔业价值,水库面积600万公顷、河道60万公里,池塘水面近40万公顷及三个内陆海。内陆水域鱼产量1,100万公担,其中湖泊渔业96万公担,河流捕捞161万公担、水库66万公担、池塘养殖146万公担。  相似文献   

6.
几十年来,我国陆续从国外和境外引进了几十种淡水食用鱼类,其中有十几个养殖品种在生产中表现出较好的生长性状,已获得较高的经济效益。如罗非鱼目前年产量已达数十万吨,超过了世界其他国家的总和。这些引进的新品种数量虽然不多,但对我国渔业发展起到了促进作用。  相似文献   

7.
<正> 我省内陆水域面积很大,有大中型水库21座,中型水库40座,再加衡水湖和白洋淀,总养鱼面积8hm~2。充分开发利用我省的大中型水域发展渔业生产,提高大中型水域的生产力,是今后我省淡水渔业发展的重要战略问题,是渔业生产的后劲和希望所在,是落实“5555”工程的重要措施,也是我省100多万移民脱贫致富奔小康的必由之路。几年  相似文献   

8.
我国内陆大中型水域长期以来,主要进行单一的捕捞生产。由于捕捞强度大,渔业生产秩序较乱,水产资源得不到恢复和发展,捕捞产量逐年下降。即使开展养鱼生产的中小型湖泊,亩产一般也只有15公斤左右。八十年代初,开始探索在大中型水域中进行以人工放养鱼种、人工喂养饵料为主的集约化养殖,由于湖泊、水库等水域具有比池塘更优越的生态条件、产量、产值和利润比原来捕捞和粗放粗养大幅度增长。因此,引起了人们对大水域生产开发的重视。近十年,在各级政府的重视和支持下,  相似文献   

9.
董文 《齐鲁渔业》2011,(11):49-50
山东省内陆养殖面褪为24万hm^2(360万亩)左右,养殖产量在100万t左右,内陆捕捞产量13万t。内陆渔业养殖方式主要以池塘养殖、湖泊、水库“三网”养殖、工厂化养殖以及沿黄盐碱涝洼地“上农下渔”生态渔业为主。从经济层面上看,20世纪80年代初到90年代中期,水产养殖处于数量增长时期,90年代中期以后,由数量型向质量效益型转变,现阶段正处于产品质量安全和养殖生产效益并重的新时期。从总体来看,内陆渔业生产的总体效益逐年下降,近几年虽有所回升,但目前各种农产品价格上涨,唯独淡水产品涨幅最小,从而影响群众收入的增长。  相似文献   

10.
世界诸国内陆水域放流增殖渔业资源概况   总被引:1,自引:0,他引:1  
  相似文献   

11.
Introduced and translocated fish species in the inland waters of Greece   总被引:5,自引:0,他引:5  
Over the last 7 decades, 23 exotic fish species have been introduced into the inland waters of Greece. Some introductions were deliberately planned to take advantage of particular ecological or economic qualities of the species concerned. These include rainbow trout, Oncorhynchus mykiss (Walbaum), Pacific salmon, Oncorhynchus sp., vendace, Coregonus lavaretus (L.), grass carp, Ctenopharyngodon idella (Valenciennes), and silver carp, Hypophthalmichthys molitrix (Valenciennes). Other introductions, such as that of pumpkinseed, Lepomis gibbosus (L.), and false rasbora, Pseudorasbora parva (Temminck & Schlegel), were unintentional. Further transfers were made of species between various basins within the country, including common carp, Cyprinus carpio L., tench, Tinca tinca (L.), crucian carp, Carassius auratus gibelio (Bloch), bitterling, Rhodeus amarus (Bloch), and Aristotle's catfish, Silurus aristotelis Garman. Some species have become fully acclimatized and have built up important populations. In other cases, the transfers and introductions have had considerable negative impacts, particularly where introduced species have outcompeted native forms, as in the cases of the mosquito fish, Gambusia affinis (Baird & Girard), versus Greek toothcarp, Valencia letourneuxi (Sauvage), in the western Greek marshes, and of Aristotle's catfish versus the wels, Silurus glanis L., in Lake Volvi.  相似文献   

12.
Fish stocking and regulation of fishing activities are widely implemented by freshwater fisheries authorities who have to protect aquatic communities. The effects of fish management on fish communities have not received sufficient attention. As a result of two datasets, one from EU Water Framework Directive (WFD) monitoring surveys, and one from a French survey targeting angler's associations, this study investigated the impacts of both fishing intensity and fish stocking on fish communities in French lakes. Both co-inertia analysis and community size spectra analysis, showed that: (i) stocking does not contribute to the standing stocks for five of the six most stocked fish species in France; and (ii) neither fishing intensity nor fish stocking lead to a change in the proportion of large and small fish. The results support alternative methods being promoted to enhance native fish populations.  相似文献   

13.
介绍了2005-2008年在国内内陆水体鱼类资源调查中,EY60回声探测仪的使用及其效果.该探测仪利用分裂波束(Split-beam)技术,通过交叉过滤(Cross-filter)及轨迹跟踪分析(Tracking analysis),实现了对鱼类个体的自动判别及计数;另外对使用中噪声消减、渔获物调查数据的参考等进行了说明;强调回声探测仪自主品牌产品研发的必要性.  相似文献   

14.
A total of 14.573 million fish fry and 96.32 million shrimp larvae were released across 31 locations into the coastal waters off Guangdong, China, in 2010. The released fish and shrimp were sampled through a combination of market and fishing log‐book surveys. The combined fishery production reached 362 868 kg. The input–output ratio was 1:5.99 for released fish (over 3 years) and 1:11.01 for released shrimp (over 2 years). The average increase in income was 721 RMB per capita. Approximately 240 thousand fish (after 3 years) and 1.2 million shrimp (after 2 years) survived to sexual maturity and could contribute to the spawning stock. The stockings were approximately one‐seventh of the fish and one‐half of the shrimp stocking carrying capacities, respectively. Based on these results, the intensity of stocking could be increased. Stocking and recapture strategies should be adjusted to align with the optimal stocking carrying capacity determined from this study.  相似文献   

15.
Stocking and fishing effort are two important potentially conflicting factors in fish stock management that require appropriate assessment to ensure a sustainable fishery. In the River Tornionjoki, which discharges into the northern Baltic Sea, a summer‐ascending whitefish, Coregonus lavaretus L., stock has long been a target by traditional dipnet fishing. Enhancement stocking of young whitefish started in the River Tornionjoki in the 1970s after a collapse in catches, with millions of age‐0 whitefish stocked annually in the river, but after about three decades, the stocking rates were considerably reduced. As a result, dipnet catches of whitefish in the Kukkolankoski Rapids rose simultaneously, peaking in the 1980s and 1990s, and then subsequently decreased. There was a significant positive correlation between stocking intensity and catch, both in weight and in numbers, revealing a strong relationship between whitefish releases and dipnet catch. Changes in gillnet fishing effort in the sea affected dipnet catches in weight as well as in mean size of captured whitefish. When the combined effect of stocking and gillnet effort was evaluated, only stocking significantly affected dipnet catches.  相似文献   

16.
换水率和密度对刺参生长和水质的影响   总被引:1,自引:0,他引:1  
为探究日换水率(0、10%、20%、30%和100%)和养殖密度[0.980±0.008、1.760±0.005、2.810±0.007和(3.640±0.006)kg/m3]对刺参(Apostichopus japonicus)生长率和养殖水质的影响,养殖试验首先在非循环水养殖条件下,测定各组刺参综合特定生长率(ISGR)及养殖水体中氨氮及亚硝酸盐氮质量浓度。结果显示,日换水率为10%和20%处理组的ISGR分别达到每天(1.330±0.161)%和(1.410±0.182)%,显著高于其他处理组;密度养殖试验证明,随着养殖密度的增加,ISGR逐渐降低,分别达到每天(0.610±0.500)%,(0.570±0.030)%,(0.560±0.045)%和(0.320±0.040)%,各组换水率及养殖密度组水体中氨氮及亚硝酸盐氮均在安全浓度范围内波动;养殖结果显示,循环水养殖试验组刺参的ISGR高于非循环水养殖组,可达(0.130±0.007)%,且氨氮及亚硝酸盐氮质量浓度在0.020 mg/L以下,而非循环水养殖的分别积累到(0.600±0.015)mg/L和(0.076±0.002)mg/L。研究表明,在换水率15%,养殖密度(2.810±0.007)kg/m3的循环水养殖条件下,可以保证水体水质稳定,刺参生长良好。  相似文献   

17.
Commercial catch and fisheries monitoring data were compared with hydrological and water course characteristics conditions to identify the cause of changes in fisheries production in Berlin water courses since the 1950s. The urban parts of Berlin are densely populated, and the waters are under pressure from shipping, hydraulic engineering, pollution and recreation use. Most Berlin waters are polytrophic or hypertrophic, with an annual nutrient input of 595 t of total phosphorous and 8640 t of total nitrogen. A total of 34 fish species were recorded, eight of which were introduced. According to historical records, seven native fish species are extinct or missing. At present, the fish community is dominated by a few eurytopic species, i.e. roach, Rutilus rutilus (L.), common bream, Abramis brama (L.), silver bream, Blicca bjoerkna (L.), and perch, Perca fluviatilis L., which contribute 85% of all individuals caught. Two 'faunal breaks' were identified. The first was the changing of river character from a barbel to bream zone caused by damming and river regulation. This started in the thirteenth century and ended at the beginning of the twentieth century with the extinction of anadromous fishes. The second break was during the 1960s and 1970s, with the eutrophication of Berlin waters and the near total loss of submerged macrophytes. All phytophilic fish species declined greatly and a mass development of eurytopic species started. The catch of pike, Esox lucius L., common carp, Cyprinus carpio L., and tench, Tinca tinca (L.), became negligible, and at present, eel, Anguilla anguilla (L.), and pikeperch, Stizostedion lucioperca (L.), are the main commercial fish species. Concomitantly, the profitability of the fisheries declined and was linked to a decrease in the number of people employed in fisheries by more than 75% compared with 1950.  相似文献   

18.
Soil and water interactions and their influence on growth and production in different densities (SD8 & SD16) under zero water exchange were studied in two successive crops of Penaeus monodon in Tamil Nadu, India during 2007 and 2008. Scraping and tilling during pond preparation increased the mineralization rate than scraping only. During crop, there was no significant difference in soil organic carbon and total nitrogen between the SDs. However, as the crop progressed, organic carbon and total nitrogen content of the soil showed significant difference under both the SDs. Between the SDs, nitrate and phosphate content in water significantly differed, whereas the progress of the crop significantly increased both available and total nutrients. Mass balance of nitrogen indicated that applied feed contributed to 97.4–98.5% of input nitrogen, of which nitrogen in sediment accounted for 16.5–27.3%, nitrogen recovery in shrimp was 34.2–43.6% and the nitrogen lost through denitrification and volatilization varied from 4.7% to 34.7%. Zero water exchange system is highly efficient as nitrogen recovery is higher in shrimp and lower in discharge water. Lack of significant difference in metabolites between the SDs indicates the role of aeration and probiotics in sustaining SD16 cultures.  相似文献   

19.
工厂化养鱼供水量和供气量的确定   总被引:2,自引:0,他引:2  
综合工厂化养鱼池内进水、排水、供气、生物代谢、饵料投喂和有害物质降解的关系,利用的料平衡原理、微生物降解动力学原理、生物能量学原理和养鱼池的水力特性,建立供水量、供气量与产氮率、耗氧率、产BOD率的关系式,提出工厂化养鱼场供水量和供气量的计算方程式和方法。  相似文献   

20.
分别进行水温和密度对大鳞鲃(Barbus capito)幼鱼的生长影响实验,旨在探索大鳞鲃适宜的放养密度和生长温度。水温实验设计为6个梯度值15℃、18℃、21℃、24℃、27℃、30℃,幼鱼初始体重为9~12 g,投喂75 d后,结果得出:在水温15~27℃时,随着温度的升高,终末体重会逐渐增加,27℃时最大值为(44.47±9.54)g,水温达到30℃时,终末体重开始下降。24℃、27℃和30℃组体重增长无显著差异,但温度达到30℃时,体重变异系数最大,为(29.82±11.36)%。密度实验设计为4个梯度值20 ind/m3、15 ind/m3、10 ind/m3、5 ind/m3,幼鱼初始体重为0.6~0.7 g,投喂60 d后,结果得出:随着放养密度的下降,体重增长的速度越快。体重、特定增长率、日增重变化在密度为5 ind/m3时最高,密度10 ind/m3与15 ind/m3没有显著差异,达到20 ind/m3时会显著下降。综合考虑,大鳞鲃适宜的养殖温度在24~27℃,静水池塘的放养密度建议在15 ind/m3左右。  相似文献   

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