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91.
92.
青蛤生境及生长   总被引:11,自引:1,他引:11  
于业绍 《水产学报》1995,19(3):276-279
青蛤生境及生长HABITATANDGROWTHOFCLAM(CYCLINASINENSISGMELIN)¥YuYeshaoandWangHui(EastChinaSeaFisheriesResearchInstitute,ASF,Shanghai20...  相似文献   
93.
We have developed a set of tools that operate within an aquatic geographic information system to improve the accessibility, and usability of remote‐sensed satellite and computer‐modeled oceanographic data for marine science and ecosystem‐based management. The tools form the Pelagic Habitat Analysis Module (PHAM), which can be applied as a modeling platform, an investigative aid in scientific research, or utilized as a decision support system for marine ecological management. Applications include fisheries, marine biology, physical and biological oceanography, and marine spatial management. The GIS provides a home for diverse data types and automated tools for downloading remote sensed and global circulation model data. Within the GIS environment, PHAM provides a framework for seamless interactive four‐dimensional visualization, for matching between disparate data types, for flexible statistic or mechanistic model development, and for dynamic application of user developed models for habitat, density, and probability predictions. Here we describe PHAM in the context of ecosystem‐based fisheries management, and present results from case study projects which guided development. In the first, an analysis of the purse seine fishery for tropical tuna in the eastern Pacific Ocean revealed oceanographic drivers of the catch distribution and the influence of climate‐driven circulation patterns on the location of fishing grounds. To support management of the Common Thresher Shark (Alopias vulpinus) in the California Current Ecosystem, a simple empirical habitat utilization model was developed and used to dynamically predict the seasonal range expansion of common thresher shark based on oceanographic conditions.  相似文献   
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长鳍金枪鱼(Thunnus alalunga)经济价值高,是我国延绳钓渔业重要的目标鱼种。根据2013年9月~2014年1月和2014年4~8月我国金枪鱼观察员在南太平洋东部海域收集的长鳍金枪鱼样本和海洋环境数据,对其生物学组成和栖息环境进行了研究。结果表明:叉长(FL,cm)与体质量(WW,kg)的关系为:WW=3×10-5×FL2.909 9(雌雄性,R2=0.915 3);体长(TL,cm)与叉长(FL,cm)关系为:TL=1.033 6FL+2.555(R2=0.961 4);叉长(FL,cm)与两背鳍间距(LD1D2,cm)的关系为:LD1D2=0.248 5FL+1.238 1(R2=0.815 1);利用各水层长鳍金枪鱼渔获率(catch per unit effort,CPUE)推测其主要的栖息水层为150~270 m,栖息水层温度范围16~22℃,盐度范围35.0~35.6,其中最高资源丰度主要分布在190~230 m的水层,对应的温度为18~20℃,盐度为35.2~35.4。研究结果可为掌握南太平洋长鳍金枪鱼栖息环境提供基础数据。  相似文献   
95.
鱼类在遭受捕食后,受损的表皮会释放大量的化学信号物质,同种其它个体嗅到这些化学信号后会作出躲避反应,称为报警反应(alarm response),报警反应通常出现在一定的发育阶段。采用斑马鱼(Dinio rerio)同种碾碎提取物(处理组,质量浓度为10-6g·L-1)作为报警物质,并设3个对照组:罗非鱼碾碎提取物组、双蒸水组、空白对照组,通过暴露处理实验,检测沉底累积时间(time of bottom)、呆滞累积时间(time of freezing)两项指标,研究了28 dpf(days post fertilization,受精后天数)、35 dpf、42 dpf 3个不同发育时期幼鱼的报警反应。结果显示:28 dpf时,处理组与3个对照组相比,在沉底累积时间、呆滞累积时间两项指标上均无显著差异,这个时期处理组有2 ind斑马鱼出现"沉底",其中1 ind出现"呆滞";35 dpf时,处理组与3个对照组相比,在沉底累积时间上有显著差异(P0.05),在呆滞累积时间上无显著差异,这个时期有5 ind斑马鱼出现"沉底",其中1 ind出现"呆滞";42 dpf时,处理组与对照组相比,在沉底累积时间、呆滞累积时间两项指标均有显著差异(P0.05),这个时期有8 ind斑马鱼出现"沉底",且8 ind全部出现"呆滞",与此对应的是这个时期大部分个体出现明显的报警反应。研究表明,斑马鱼报警反应产生的发育阶段为35~42 dfp之间,结合已知的野外斑马鱼生活史,推测斑马鱼在特定的阶段产生报警反应可能与栖息地的迁移有关。  相似文献   
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Variation in the distribution and abundance of nearshore fishes is critical to understand food web processes and fishery management issues in Lake Michigan. This study characterised patterns in abundance of three common nearshore species, yellow perch Perca flavescens (Mitchell), round goby Neogobius melanostomus (Pallas) and alewife Alosa pseudoharengus (Wilson), in relation to spatio‐temporal, abiotic and biotic factors using gillnet sampling conducted across 5 years at multiple locations representing different substrates. Significant variations were observed in alewife and round goby catches between locations. A negative relationship between round goby and age‐0 yellow perch catch was observed, indicating potential competition between the two species. This study demonstrates that variability in nearshore fish communities can be driven by factors including substrate and interspecific interactions. Given the prominent role these species play in Lake Michigan's food web and thus their importance to fishery production, a thorough understanding of these factors is warranted.  相似文献   
99.
东南太平洋智利竹筴鱼栖息地指数的比较研究   总被引:5,自引:0,他引:5  
方宇  邹晓荣  张敏  谢峰  吴昔磊 《海洋渔业》2010,32(2):178-185
根据2000~2007年度东南太平洋智利竹筴鱼的商业捕捞数据,结合海洋环境数据(SST,SSA,SSHG以及等温层深度),运用4种关联建模方法计算其栖息地指数,并使用Surffer 8.0软件绘制出HSI的空间分布图。通过2008年度的捕捞数据进行验证,结果表明4种模型的结果存在明显差异:采用算术平均法和几何平均法时,主要产量分布在0.6HSI0.9的区域;采用最大值法时,主要产量集中在0.8HSI1.0的区域;采用最小值法时,主要产量分布在0.3HSI0.6的区域。通过4种模型的验证结果比较,本文认为算术平均法和几何平均法能较好地反映东南太平洋智利竹筴鱼的中心渔场位置以及分布特征。  相似文献   
100.
Abstract  Movements by adult cutthroat trout, Oncorhynchus clarkii (Richardson), were assessed from autumn to summer in the Salt River watershed, Wyoming-Idaho, USA by radio telemetry. Adult cutthroat trout were captured during September and October 2005 in the main stem of the Salt River, surgically implanted with radio transmitters, and tracked through to August 2006. Adult cutthroat trout were relatively sedentary and resided primarily in pools from October to March, but their movement rates increased during April. Higher movement rates were observed among tagged fish during May and early June. Among 43 fish residing in the Salt River during April 2006, 44% remained in the river, 37% moved into mountain tributaries and 19% moved into spring streams during the spawning season. Fish did not use segments of mountain tributaries or the upstream Salt River where fish passage was blocked by anthropogenic barriers or the channel was dewatered during summer. Almost all the fish that moved into spring streams used spring streams where pools and gravel–cobble riffles had been constructed by landowners. The results suggest that adult Snake River cutthroat move widely during May and early June to use spawning habitat in mountain tributaries and improved spring streams. Maintaining the ability of adult fish to move into mountain streams with spawning habitat, preserving spawning habitat in accessible mountain tributaries and removing barriers to upstream movements, and re-establishing summer stream flows in mountain tributaries affected by dams appear to be habitat management alternatives to preserve the Snake River cutthroat trout fishery in the Salt River.  相似文献   
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