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101.
为了解湛江市海水动物副溶血性弧菌的带菌感染率及其致病性,从湛江市水产品市场随机采集海水鱼样品30份,根据中华人民共和国国家标准和进出口标准规定的副溶血性弧菌的检验方法,结合科玛嘉弧菌显色培养基分离试验,对采集样品进行了副溶血性弧菌的分离与鉴定;并用神耐川试验、溶血试验和脲酶试验检测了分离菌株的致病性。结果显示:30份海水鱼样品分离得到10株副溶血性弧菌,检出率为33.33%。其中,神耐川试验溶血强阳性5株,弱阳性2株,阴性3株;在3.5%NaC l兔血琼脂平板上,本试验分离到的10株副溶血性弧菌均呈现较强溶血作用;10株分离菌株脲酶试验均为阴性。 相似文献
102.
海洋真菌分类鉴定方法探析 总被引:1,自引:0,他引:1
详细介绍了海洋真菌现代分类鉴定方法。先考察其在不同盐度条件下的生长情况,检验分离自海洋的真菌是否为海洋微生物,然后从形态特征、生理生化特征、基因水平3方面指标综合考虑将海洋有丝真菌鉴定到种属水平,确定其系统分类地位。 相似文献
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Claus Reedtz Sparrevohn Martin Lindegren Brian R. Mackenzie 《Fisheries Oceanography》2013,22(5):400-408
The consequence of elevated ocean temperatures on commercial fish stocks is addressed using time series of commercial landings (1906–2004) and juvenile survey catch data (1904–2006) collected around Denmark. We analyze (i) whether warm‐water sole (Solea solea) has increased relative to Boreal plaice (Pleuronectes platessa) and (ii) whether two related warm‐water species (turbot, Psetta maxima and brill, Scophthalmus rhombus) show similar responses to increasing temperature or, alternatively, whether turbot (which has a broader juvenile diet) has been favored. Since the early 1980s, both sole and turbot have constituted an increasing part of the commercial landings and survey catches, as compared with plaice and brill, respectively. These changes in species composition were linked to sea surface temperatures, Northern Hemisphere temperature anomalies (NHA) and the North Atlantic Oscillation. NHA was closely related and explained 43% of the observed variation in sole survey catches relative to the plaice catches and almost 38% of the observed variation in the sole landings relative to the plaice landings. For the less common species, turbot and brill, none of the global change indicators explained more than 15% of the variation, although all showed a positive relationship. Survey catch per unit effort increased significantly for both sole and turbot around the early 1980s, whereas catch per unit effort for plaice and brill remained constant. The results indicate that the abundance of warm‐water species is likely to increase with increasing temperature but also that species with similar life histories might react differently according to degree of specialization. 相似文献
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陈严 《农业图书情报学刊》2011,23(2):78-80
以2004~2008年《海洋水产研究》发表研究生论文为统计对象,运用文献计量学的方法对载文量、发表时滞、作者群进行分析,并对今后工作提出建议。 相似文献
108.
Understanding the area use requirements of species targeted for protection by marine protected areas (MPAs) is critical to the future conservation efforts of economically important fish species. Knowledge of home range size and site fidelity is essential in determining whether species will benefit from the protection offered by a MPA, the size of the area needed to protect individuals, and the extent to which surrounding unprotected areas may be supplemented through post-recruitment movement or “spillover”. We utilized a traditional mark and recapture approach, along with GIS spatial analysis to investigate the site fidelity, home range, and homing behavior of the economically important fish species cabezon (Scorpaenichthys marmoratus) on the south central coast of California. In collaboration with members of the commercial live-fish fishery, a total of 1240 sub-adult and adult cabezon were tagged during 10 days of fishing from September to December of 2004 along ∼18 km of coastline. A public awareness and reward program resulted in 330 total recaptures from 290 different individuals (23% recapture rate) with recaptured individuals at liberty up to 1000 days after initial tagging. A majority of individuals displayed high site fidelity, with 81% of recapture events occurring within 100 m of their initial capture locations, and only 9 individuals (.03%) recaptured greater than 1 km. Most individuals (64%) displayed home ranges less than 1000 m2. Ten individuals recaptured after experiencing translocation of up to 5.3 km displayed strong homing behavior, returning to within 14 m of their initial capture locations. Findings suggest that under circumstances where suitable habitat is available in nearby unprotected areas, that adult “spillover” will likely be limited to areas within 100 m from MPA boundaries. In addition, the size of the area needed to protect individual cabezon, should be at least 1000 m2. Findings from this study demonstrate many of the potential benefits of scientists and fishers working together to investigate area use patterns of economically important fish species to facilitate future design and assessment of MPAs. 相似文献
109.
鱼类是一个迄今尚未被认知的非常重要的微细碳酸盐沉积物的来源,对海洋固碳有着重要作用,这个发现直接影响到碳汇渔业的内涵.本研究介绍了海洋硬骨鱼类渗透压调节机制及鱼类肠道碳酸盐结晶形成与其肠细胞膜上物质转运之间的关系,着重阐述了鱼类肠道碳酸盐结晶的特征,并论述了通过对特定区域内鱼类生物量和碳酸盐排泄率数据的研究,估计出全球海洋鱼类每年可产生大约1.1亿t的碳酸钙,在海洋总碳酸盐岩泥中占14%以上.研究重点论述了海水鱼类固碳的独特优势潜力,同时,提出为了更好地确定海水鱼类养殖在碳汇渔业中的地位和作用,有必要对主要海水养殖鱼类肠道碳酸结晶物的形成量及其调控机制,碳收支动态模型进行研究,进而合理地估算和测定海水鱼类养殖的碳汇量. 相似文献
110.
Peter A Robertson Tim Adriaens Xavier Lambin Aileen Mill Sugoto Roy Craig M Shuttleworth Mike Sutton‐Croft 《Pest management science》2017,73(2):273-279
Numerous examples exist of successful mammalian invasive alien species (IAS) eradications from small islands (<10 km2), but few from more extensive areas. We review 15 large‐scale removals (mean area 2627 km2) from Northern Europe since 1900, including edible dormouse, muskrat, coypu, Himalayan porcupine, Pallas' and grey squirrels and American mink, each primarily based on daily checking of static traps. Objectives included true eradication or complete removal to a buffer zone, as distinct from other programmes that involved local control to limit damage or spread. Twelve eradication/removal programmes (80%) were successful. Cost increased with and was best predicted by area, while the cost per unit area decreased; the number of individual animals removed did not add significantly to the model. Doubling the area controlled reduced cost per unit area by 10%, but there was no evidence that cost effectiveness had increased through time. Compared with small islands, larger‐scale programmes followed similar patterns of effort in relation to area. However, they brought challenges when defining boundaries and consequent uncertainties around costs, the definition of their objectives, confirmation of success and different considerations for managing recolonisation. Novel technologies or increased use of volunteers may reduce costs. Rapid response to new incursions is recommended as best practice rather than large‐scale control to reduce the environmental, financial and welfare costs. © 2016 Crown copyright. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献