水产养殖环境常见四环素类抗生素抗性基因tet（M）的演化及传播的初步分析     

陈琳琳  刘维青  刘静  张高生  任宗明 《海洋科学》2011,35(12):75-81

利用分子系统学方法分析了20 条水产养殖环境中常见的四环素抗性tet（M）基因的序列特点、多态性及系统发育, 并对其细菌寄主分类、环境介质来源作相关性分析。结果表明, 20 条基因序列有4种单倍型, 其中tet（M）-b 和d 是两种远缘基因型, 而a 和c 则是二者之间的序列变异。系统发育树分成三大分支, tet（M...  相似文献   

微生态制剂对生物挂膜及牙鲆生长的影响研究   总被引：1，自引：0，他引：1       下载免费PDF全文

傅雪军  马绍赛  曲克明  周勇 《海洋科学》2011,35(4):15-20

针对工厂化循环水养殖系统中生物滤池去除有害污染物质的核心问题,采用单因素梯度设计,添加50(1#),100(2#),250(3#),500(4#),1000(5#),1500(6#)g微生态制剂辅助自然微生物在生物载体上进行人工挂膜,挂膜2周后,进行40 d循环水养殖牙鲆(paralichthys olivaceus)...  相似文献   

Research on China’s aquaculture efficiency evaluation and influencing factors with undesirable outputs     

Ji  Jianyue  Wang  Pingping 《中国海洋大学学报(英文版)》2015,14(3):569-574

Taking the aquaculture area, the number of farming boats and that of aquaculturist as input variables, the aquaculture production as desirable output variable and polluted economic loss as undesirable ...  相似文献   

基于Google Earth Engine的红树林年际变化监测研究   总被引：1，自引：0，他引：1  

刘凯  彭力恒  李想  谭敏  王树功 《地球信息科学学报》2019,21(5):731-739

遥感技术已广泛应用于红树林资源调查与动态监测中,但仍然存在遥感数据获取困难、数据预处理工作量大、监测时间长而周期过大等问题,影响了学者对红树林演变过程的精细刻画与理解。本文基于Google Earth Engine（GEE）云遥感数据处理平台,选取Landsat系列卫星数据,生成长时间序列年际极少云影像集（云量少于5%）,利用3个红外波段反射率（NIR、SWIR1、SWIR2）和3个特征指数（NDVI、NDWI、NDMI）建立阈值规则集,实现对实验区越南玉显县红树林、红树林-虾塘、不透水面-裸地、水体4种目标地物的专家知识决策树分类和土地覆盖的制图,并基于分类结果监测该区域1993-2017年的红树林年际动态变化。结果表明：GEE平台可满足多云多雨地区红树林的长时间序列年际变化监测需求;本文阈值分类方法可以有效提取红树林及红树林-虾塘,实验区有86%年份的影像分类精度达到80%以上;年际变化监测可精细刻画实验区红树林面积先增后减再增的变化过程,也能准确反映红树林与红树林-虾塘养殖系统面积之间的负相关关系。红树林年际动态监测结果可以降低红树林演变分析的不确定性,并能更精细地量化红树林与其他土地覆盖类型的转化过程,从而评估经济发展、政策等因素对红树林演变的影响。  相似文献   

Effect of graded levels of dietary carbohydrate on growth,feed utilisation and intestinal microbial community structure in dusky kob Argyrosomus japonicus fed a pelleted diet     

NC Mabasa  PJ Britz  CLW Jones  A Nel 《African Journal of Marine Science》2018,40(3):267-277

The ability to utilise carbohydrates is limited for many predatory marine fishes. Graded levels of dietary carbohydrate (4.1–24.6%) were formulated using pregelatinised maize starch, to determine optimal levels for dusky kob Argyrosomus japonicus, an emerging mariculture finfish for which pelleted feeds are being developed. Specific growth rate increased with an increase in the carbohydrate level up to 16.72%, after which it declined. Feed utilisation followed a similar trend, with the best feed conversion ratio (1.28) and protein efficiency ratio (1.76) recorded at 16.4% carbohydrate. Lipid vacuolisation of the hepatocytes was evident in all livers examined, with melano-macrophage aggregates in those of fish fed 24.6% carbohydrate suggesting starvation. Gut bacterial community profiles were variable but were not influenced by dietary carbohydrate level and differed mostly between fish fed trout feed prior to the trial and those fed experimental diets containing starch. The dusky kob were able to clear glucose from their blood when fed up to 16.4% carbohydrate, but glucose removal was not achieved at 24.6% carbohydrate. In conclusion, dusky kob has a limited ability to utilise cooked starch as a carbohydrate source, which may be included in pelleted feed at 16.4% without adverse effects. For this species, levels of dietary carbohydrate above this may result in symptoms consistent with physiological breakdown, including reduced growth, reduced feed intake and feed conversion efficiency, prolonged hyperglycaemia, liver pathology and altered microbial communities in the foregut.  相似文献   

海水甲壳类寄生性甲藻Hematodinium spp.研究进展   总被引：1，自引：1，他引：0  

李才文  许文军 《海洋与湖沼》2014,45(1):1-10

寄生性甲藻Hematodinium是一类危害海水甲壳类的致病性寄生性甲藻,在世界范围内严重威胁了多种重要经济甲壳类的渔业生产。近年来,Hematodinium先后在我国浙江、广东沿海的锯缘青蟹、三疣梭子蟹、脊尾白对虾等重要养殖甲壳类中报道发现, 并已确定该寄生甲藻是近年来引起当地养殖青蟹“黄水病”、三疣梭子蟹“牛奶病”和脊尾白对虾大规模死亡的主要病原之一。本文结合作者近年来Hematodinium的研究成果,系统综述了国内外该寄生性甲藻的研究进展,包括其系统分类、生活史、传播途径、发生机制等;并针对目前该寄生性甲藻研究中存在的关键问题,结合我国相关研究的现状做出了分析和展望,以期为我国海水甲壳类寄生性甲藻发生的预防与控制提供理论依据和技术支持。  相似文献   

Response of benthic opportunistic polychaetes and amphipods index to different perturbations in coastal oligotrophic areas (Canary archipelago,North East Atlantic Ocean)     

Rodrigo Riera  Jose Antonio de‐la‐Ossa‐Carretero 《Marine Ecology》2014,35(3):354-366

Oligotrophic areas harbour low macrofaunal abundance and patchy distribution. In these areas it is necessary to test the reliability of biological indicators, especially those based on taxonomic sufficiency where the level of identification is balanced against the need for ecological information and could affect the efficiency of bioindicators. The BOPA (benthic opportunistic polychaetes and amphipods) index was applied in five coastal areas subjected to different perturbations (aquaculture, harbour, brine, sewage, and thermal pollution) in the Canary archipelago, an oligotrophic area of the Atlantic Ocean. Significant differences in the BOPA index between impact and control sites were only found in the area affected by a harbour. Perturbations such as aquaculture, brine or sewage discharge produce only a weak response of the BOPA index, whereas no effects were observed at thermal pollution‐impacted locations. The BOPA index should be used with caution to establish the ecological status of coastal water bodies in the Canary Islands, since it was only reliable in strongly impacted regions (enlargement harbour works), but did not respond clearly to other man‐induced perturbations.  相似文献   

砗磲研究现状及在我国南海开展养殖的前景   总被引：4，自引：0，他引：4       下载免费PDF全文

周勤  王玉芬  姜秀凤 《热带海洋学报》2014,33(2):87-93

砗磲是软体动物门瓣鳃纲砗磲科生物的统称,广泛分布于热带珊瑚礁海域。20世纪八九十年代,澳大利亚、美国以及菲律宾等太平洋岛屿国家集中开展了砗磲增养殖及与之相关的生理、生态和经济学等基础研究。砗磲通过与其共生的虫黄藻获得营养,这一特性使得砗磲生长速度极快。砗磲的单位面积保有量可达400t·hm-2,使得它们在热带珊瑚礁海域中具有重要的生态学和养殖意义。不仅如此,砗磲在其生长过程中所体现出来的珊瑚礁修复价值以及碳汇渔业价值对于海洋开发和保护都有着极其重要的意义。同时,我国南海拥有环境优越的广阔热带海域,可开展砗磲养殖的面积达3000km2以上。结合以上认识,作者认为砗磲养殖具有形成热带海洋贝类养殖重大产业的潜力,可以为我国南海珊瑚礁保护和生态文明建设工程提供支撑。  相似文献   

Effect of hydraulic loading rate on the efficiency of effluent treatment in a recirculating puffer aquaculture system coupled with constructed wetlands   总被引：1，自引：0，他引：1  

Jiabo Xu  Yonghai Shi  Genyu Zhang  Jianzhong Liu  Yazhu Zhu 《中国海洋大学学报(英文版)》2014,13(1):146-152

Constructed wetlands(CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer(Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate(HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions(salinity 7.4–7.6) at 3 different HLRs(0.762, 0.633, and 0.458 m d–1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen(by 81.03–92.81%) and nitrite nitrogen(by 99.40%–99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids(TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.  相似文献   

人工湿地净化高盐度养殖废水的效果     

刘永士  施永海  张根玉  张海明  邓平平  张宗锋 《广东海洋大学学报》2014,(3):70-75

研究了人工湿地循环处理哈氏仿对虾(Parapenaeopsis hardwickii)高盐度(21.1-23.3)养殖废水的净化效果。人工湿地对高盐度养殖废水中各水质指标去除率为:总氨氮66.7%,亚硝酸盐80.0%,化学需氧量12.5%,浊度69.1%,硝酸盐-12.1%,总氮3.5%,总磷0.0%。养殖池水质状况良好。在试验负载范围内,湿地对总氨氮、亚硝酸盐、浊度的去除量随进水污染负载量的增加而增加。研究表明:人工湿地能持续有效降低哈氏仿对虾养殖废水中的主要水质因子浓度。  相似文献