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1.
海洋生物资源的可持续开发和利用已成为全球海洋生物资源管理的重心。预警原则作为一种新颖的环境资源管理手段,其对海洋生物资源养护的有效性已为一些国际协定和一些国家的国内立法所确认。目前我国海洋生物资源管理实践和相关法规并没有明确采用预警原则。因而,针对我国近海生物资源养护不利的现状,我国有必要增订相关立法,将预警原则规定为我国海洋生物资源管理的基本原则,并根据我国各海域的具体情况,有针对性的适用预警原则,以顺应全球海洋生物资源养护的大趋势。  相似文献   

2.
中肋骨条藻的室内筛选室外培养技术   总被引:1,自引:0,他引:1  
骨条藻生长繁殖速度快、不容易污染。在室内水泥池中,从自然海水里筛选生产性纯种骨条藻藻液,在室外土池里通过对骨条藻生长繁殖所需要的各项理化因子、生物因子的控制,快速培养骨条藻。该技术简单、生产操作容易,适应于大规模的生产使用。  相似文献   

3.
养虾池底播魁蚶技术研究   总被引:3,自引:0,他引:3  
对养虾池混养魁蚶的底质选择、播苗密度、苗种规格、池水调近和魁蚶在虾池中越冬等进行了试验研究,270亩混养试验池,平均亩产对虾106.3kg,魁蚶124.1kg,混养比单养平均亩增效益1438.4元,总增效益38.84万元。技术鉴定认为:本研究成果属国内领先水平。  相似文献   

4.
辽宁是重要渔业省份之一,海岸线较长,渔船渔港众多,全省沿海25个县(市、区)拥有渔民20余万人,各类渔船3万多艘。长期以来,因海上生产条件差,环境极其恶劣,渔船比较分散,管理难度越来越大,渔业安全生产形势十分严峻,各类渔船海损事故频繁发生,给渔民造成极大损失,  相似文献   

5.
牛蛙爱德华氏菌病病原菌的鉴定和致病因素的研究   总被引:5,自引:1,他引:5       下载免费PDF全文
从患爱德华氏菌病的牛蛙肌肉、肝、肾、血液和腹水中分离到8株细菌,根据其形态和生理生化特性鉴定为野生型迟钝爱德华氏菌。人工感染实验均为该病的病原菌,毒素检测试验表明,致病因素主要是内毒素而不是外毒素。分离菌株的主要特性为杆状、革兰氏阴性、周生鞭毛、兼性厌氧。接触酶、甲基红试验和硝酸盐还原均为阳性。在三糖铁琼脂上产H2S。氧化酶、丙二酸盐利用、V.P试验、明胶液化、尿素酶。苯丙氨酸脱氨酶为阴性。分解葡萄糖、甘露糖、麦芽糖,产酸产气,不利用甘露醇、蔗糖和阿拉伯糖。  相似文献   

6.
The oogenic cycle and biochemical composition of the ovary of raft-cultured great scallop (Pecten maximus) were studied during the period April 1990–July 1991. The ovary condition index (FGI) and stereological studies showed the existence of two principal spawning periods, winter and late spring-early summer. No sexual resting period was found. Oocyte lysis was high throughout the year. Ovarian lipid levels displayed a clear seasonal pattern linked to the gametogenic cycle. Total lipid (TL, 16–21% dry weight), acylglycerol (AG, 20–65% TL) and free sterol (FS, 2.8–6.4% TL) levels were, generally, higher in the ripe ovary and a decrease coincided with spawning. Protein (59–63% dry weight), glycogen (<3% dry weight) and phospholipid (PL, 26–35% TL) levels showed no clear seasonal trend. The TL and AG were a good index of ovarian sexual maturity. The TL % of dry weight) correlated well with the female gonad condition index (r s = 0.779, p < 0.001), and AG (% f TL) correlated well with the mean oocyte diameter (r s = 0.630, p < 0.01) and the female gonad condition index (r s = 0.443, p < 0.05).  相似文献   

7.
温度对三疣梭子蟹行为的影响   总被引:1,自引:0,他引:1  
描述了三疣梭子蟹的摄食、领域、防御、攻击及清洁行为。三疣梭子蟹在水温12℃以上摄食行为加强,领域与攻防行为也很明显,攻防主要其螯肢。三疣梭子蟹的清洁行为比较复杂,在光强度变化较大时较为明显,一般要持续15~20min。随着温度的降低,三疣梭子蟹的摄食、攻防、领域行为都明显减弱。  相似文献   

8.
进行了美国杂交条纹鲈的苗种培育试验,科学调节池塘水体理化因子,初步探讨了美国杂交条纹鲈生长的适宜生态条件。认为美国杂交条纹鲈适温范围广,苗种培育过程中溶解氧应在4mg/L以上,碱度、硬度保持3me/L左右,pH8.0以上,COD应在10mg/L以下,对氮、磷营养元素和苗种培育饵料生物也进行了分析。  相似文献   

9.
沸石在河蟹育苗中的应用   总被引:4,自引:0,他引:4  
宋继周 《齐鲁渔业》1999,16(3):10-11
在河蟹育苗中,利用沸石作水质净化剂.从幼体蚤状Ⅲ期始,每天在3个幼体培育池共90m3水体中投放200×10-6沸石。结果试验组每m3水体大眼幼体出苗量增加54g,效果明显。试验证实,投放沸石能吸附水中有机污染物,降解氨氮,净化水质,促进幼体正常变态发育。  相似文献   

10.
为了解十年禁渔背景下大宁河鱼类早期资源变化状况,2020和2021年5-7月在大宁河龙溪断面开展了鱼类早期资源现状的调查。结果表明,龙溪江段产浮性卵鱼类1种、漂流性卵鱼类4种、粘沉性卵鱼类19种;中华纹胸鮡(Glyptothorax sinensis)和大眼鳜(Siniperca kneri)的产卵规模相对较大,其卵占比分别达48%和30%以上;2020年的鱼类卵苗资源量和种类都少于2021年。RDA分析结果显示,中华纹胸鮡(Glyptothorax sinensis)、张氏?(Hemiculter tchangi)鱼卵漂流密度与水温变化呈现一定相关性,适宜水温促使中华纹胸鮡(Glyptothorax sinensis)、张氏?(Hemiculter tchangi)产卵;随着流速和流量增加,多鳞白甲鱼(Scaphesthes macrolepis)和云南盘鮈(Discogobio yunnanensis)卵漂流密度均相应增加;大眼鳜(Siniperca kneri)和峨眉后平鳅(Metahomaloptera omeiensis)产卵期间江水酸碱度相对较低。十年禁渔的实施对大宁河鱼类资源的恢复可能产生积极影响。  相似文献   

11.
沙门氏菌是一类革兰氏阴性、长有鞭毛的兼性需氧菌,多数存在于动物的排泄物中,其引起食物中毒的发病率极高.本文对沙门氏菌的三种主要检测方法:微生物学检测法、酶联免疫吸附法、PCR快速检测技术的实验方法、注意事项以及优缺点进行探究,对于更为准确快速鉴定沙门氏菌,防止沙门氏菌进一步蔓延具有一定的意义.  相似文献   

12.
Predicting the temperature of the Barents Sea   总被引:4,自引:0,他引:4  
Knowledge of the influence of the physical environment on commercially important fish stocks in the North Atlantic has increased during the last decade. To allow this information to be used in fisheries management, some forecast of the environment is important. Predictions of temperature in the Arcto-boreal Barents Sea have been given for many years, both as subjective opinions of scientists and implicitly in stock assessment assumptions of, e.g., mortality rates. To evaluate an objective statistical forecasting system, we have analysed time series representing mechanisms previously proposed as influencing the temperature of the Barents Sea. These include components of suggested periodic nature, large-scale advective effects, regional processes, and atmospheric teleconnections. The predictability of Barents Sea temperature based on the above mechanisms was evaluated through calculations of auto- and cross-correlations, linear regression, spectral analysis and autoregressive modelling. Forecasts based on periodic fluctuations in temperature performed poorly. Advection alone did not explain a major part of the variability. The precision of predictions six months ahead varied with season; forecasts from spring to autumn had least uncertainty. A first-order autoregressive model, including modelled atmospherically driven volume flux to the western Barents Sea during the preceding year and the position of the Gulf Stream off the eastern coast of the USA two years earlier, explained 50% of the total historical temperature variability.  相似文献   

13.
During 1997 and 1998, unusual physical conditions occurred in the Bering Sea: strong May storms and calm conditions in July; record high sea surface temperature; a shallow wind mixed layer; a fresher-than-normal water column; and abnormal cross-shelf currents. Accompanying these conditions were changes in the dominant phytoplankton, a die-off of seabirds, increased sightings of large whales and diminished returns of salmon. Changes to the physical environment during 1997 and 1998 are placed in context of historical meteorological and oceanographic data sets. Although 1997 had the warmest sea surface temperature ever observed on the south-east Bering Sea shelf, the heat content of the water column was cooler than average. In contrast, during 1998, the sea surface temperature was cooler than in 1997 but the water column had significantly higher heat content. During recent years, the water column has freshened over the middle shelf because of increased sea ice and reduction of on-shelf transport of the saline, high-nutrient water from the slope. The timing of the spring bloom is directly related to the presence of ice. When ice is advected over the south-east shelf during March/April an early, sharp phytoplankton bloom occurs. The absence of ice during this critical time is associated with a May/June bloom.  相似文献   

14.
草鱼饲料中添加黄霉素的应用试验   总被引:4,自引:1,他引:4  
通过在草鱼配合饲料中添加3×10-6黄霉素的对照试验,表明可以提高草鱼的生长速度达18个百分点,降低饲料系数达0.16,每千克鱼的饲料成本可降低9.1%。  相似文献   

15.
汉江中游秋季浮游植物的初步研究   总被引:3,自引:1,他引:3  
在汉江中游干流和支流设8个采样点对浮游植物进行监测,共检出浮游植物7门75属173种。硅藻门80种,占46.24%;绿藻门48种,占27.75%;蓝藻门31种,占17.92%;裸藻门8种,占4.62%;隐藻门3种,占1.54%;甲藻门2种,占1.16%;金藻门1种,占0.51%。干流丹江口数量最高,为174×104个/L,回流湾数量最低,为31.8×104个/L;支流唐白河为2588×104个/L。生物量干流皇庄最高,为1.8328mg/L;回流湾最低,为0.1890mg/L;支流唐白河为3.3840mg/L。汉江中游浮游植物数量、生物量总的趋势是越接近下游越高,与过去监测资料相比有逐年增加的趋势,这与水质越接近下游污染越重且污染逐年加重密切相关。  相似文献   

16.
对虾幼体停食病是近年来对虾苗种生产中的一种严重疾病,本文就其表现症状、防治实践和防治效果等进行了详细描述,并就与此相关的外源亲体和幼体的引入以及苗种生长中的幼体消毒和水处理工艺等问题进行了探讨,提出了防治途径与技术措施。  相似文献   

17.
用8种弧菌对斑节对虾受精卵和无节幼体进行感染试验,结果表明,8种弧菌严重地影响虾卵的孵化和幼体的正常发育,其中以混合弧菌感染致病性最强。试验还显示了弧菌对越是早期的胚胎侵害力越强。  相似文献   

18.
对不同品系的低孵化率卤虫卵进行了孵化对比试验,分为试验组和对照组,其中试验组添加孵化强化剂与对照组进行同等条件的试验,2组对照组的孵化率分别是66.8%、64.9%,试验组的孵化率分别是84.3%、81.5%增幅超过15个百分点,说明这种针对低孵化率卤虫卵研制的强化剂有效可行,可做进一步推广试验。  相似文献   

19.
太湖鲢、鳙的食物组成及渔获量变化原因分析   总被引:1,自引:0,他引:1  
通过食物组成分析,并结合多年渔获量统计和环境监测资料,就太湖鲢、鳙鱼渔获量变化的原因及对环境的影响进行了分析。结果表明:在9~12月份期间,微囊藻约占鲢、鳙食物体积比的90%以上;鲢、鳙渔获量在1983~2004年期间波动在(1305.4±380.0)t,占鱼类总产量的(7.18±3.32)%,其中仅1984、1985年接近2000 t。在富营养化条件下,太湖鲢、鳙鱼主要摄食微囊藻。影响其产量变化的主要原因是苗种放养量不足、捕捞强度过高和富营养化提供了充足饵料。提高鲢、鳙放养量,不仅可以利用富营养化条件下的微囊藻饵料资源,而且可以抑制太湖蓝藻暴发。  相似文献   

20.
分析了不同学者对河纯毒素起源的几种解释,从遗传学角度解释河纯毒素是河纯在长期进化过程中自然选择的结果的解释较为合理。本文对河豚毒素的检测方法进行了综述。河豚毒素是钠离子通道阻断剂,是一种强海洋神经毒剂,结合国内外研究现状介绍了河鲍毒素的控毒手段以及河纯毒素作为一种工具药在临床上的应用前景。  相似文献   

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