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Modeling and Optimization of Interaction between Small Coastal Pelagic Fish, their Biological Predators and Fishermen
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作者 Ibrahima Diedhiou Salimata Gueye Diagne +4 位作者 fambaye ngom sow Coumba Diallo Diop Ndiaga Thiam Gabriel Birame Ndiaye Aissatou Fall Ndoye Gueye 《Open Journal of Optimization》 2021年第1期13-27,共15页
Small coastal pelagic fish are one of the fish families most affected by sea fishing. This man-made phenomenon leads to an imbalance in the marine and coastal ecosystem and is one of the main causes of migration north... Small coastal pelagic fish are one of the fish families most affected by sea fishing. This man-made phenomenon leads to an imbalance in the marine and coastal ecosystem and is one of the main causes of migration north and offshore of the ranges. We used the ordinary differential equations to model the interactions existing between small pelagic resources and fishermen. Modelling follows the same of the Lotka-Volterra equations with a difference in the number of variables. This study confirmed the instability of the marine ecosystem. The objective is first of all to model a system of three interacting individuals composed of two distinct types of predators and two types of prey, and then optimise this interaction with the aim of conserving biodiversity in the ecosystem under study. Determining the Jacobian matrix made it possible to calculate the reproduction rate basic (<em>R</em><sub>0</sub>). The study of the strong connectedness has made it possible to reduce the number of variables without losing the objective of the study. A computer program implemented on the language computer python facilitated the visualisation of the results. 展开更多
关键词 Small Coastal Pelagics Ordinary Differential Equations Modelling Optimisation Basic Reproduction Rate
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体长频率分析法在塞内加尔沙丁鱼资源开发中的应用(英文) 被引量:2
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作者 fambaye ngom sow Birane Samb 程和琴 《资源科学》 CSSCI CSCD 北大核心 2010年第4期620-626,共7页
本研究利用Incofish项目开发的可持续发展指标开展渔业资源评估应用研究。研究对象为金色小沙丁鱼(Sardinella aurita)和短体小沙丁鱼(Sardinella maderensis)。数据来源于1990年—2005年间塞内加尔个体渔业渔获量及由DR FRIDTJOF NANSE... 本研究利用Incofish项目开发的可持续发展指标开展渔业资源评估应用研究。研究对象为金色小沙丁鱼(Sardinella aurita)和短体小沙丁鱼(Sardinella maderensis)。数据来源于1990年—2005年间塞内加尔个体渔业渔获量及由DR FRIDTJOF NANSEN调查船在塞内加尔海域获得的渔获量。采用Froese(2004年)提出的三个可持续捕捞指标,为渔业资源量的开发状况作出诊断和评估。这些指标包括:渔获物中成鱼的百分比(以100%为最佳)、达到最适开捕体长鱼的百分比(以100%为最佳)和大型产卵鱼的百分比(以0%为最佳,体长大于最适开捕体长1.1倍的雌鱼即为大型产卵鱼)。分析结果表明:金色小沙丁鱼处于过度捕捞状态,幼鱼在其渔获物中占有优势地位,捕捞到的金色小沙丁鱼多数小于最适开捕体长,即生长型过度捕捞;短体小沙丁鱼处于充分开发利用状态。总体结果揭示,可持续捕捞指标能够成为替代或完善传统资源评估方法的有用工具。渔业相关的利益主体(包括公众)通过这些指标能够避免过度捕捞,从而更好地理解渔业管理。 展开更多
关键词 可持续捕捞指标 初次性成熟体长 最适开捕体长 小型中上层鱼 塞内加尔
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