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A New model to forecast fishing ground of Scomber japonicus in the Yellow Sea and East China Sea 被引量:5
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作者 GAO Feng CHEN Xinjun +1 位作者 GUAN Wenjiang LI Gang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第4期74-81,共8页
The pelagic species is closely related to the marine environmental factors, and establishment of forecasting model of fishing ground with high accuracy is an important content for pelagic fishery. The chub mackerel(S... The pelagic species is closely related to the marine environmental factors, and establishment of forecasting model of fishing ground with high accuracy is an important content for pelagic fishery. The chub mackerel(Scomber japonicus) in the Yellow Sea and East China Sea is an important fishing target for Chinese lighting purse seine fishery. Based on the fishery data from China's mainland large-type lighting purse seine fishery for chub mackerel during the period of 2003 to 2010 and the environmental data including sea surface temperature(SST), gradient of the sea surface temperature(GSST), sea surface height(SSH) and geostrophic velocity(GV), we attempt to establish one new forecasting model of fishing ground based on boosted regression trees. In this study, the fishing areas with fishing effort is considered as one fishing ground, and the areas with no fishing ground are randomly selected from a background field, in which the fishing areas have no records in the logbooks. The performance of the forecasting model of fishing ground is evaluated with the testing data from the actual fishing data in 2011. The results show that the forecasting model of fishing ground has a high prediction performance, and the area under receiver operating curve(AUC) attains 0.897. The predicted fishing grounds are coincided with the actual fishing locations in 2011, and the movement route is also the same as the shift of fishing vessels, which indicates that this forecasting model based on the boosted regression trees can be used to effectively forecast the fishing ground of chub mackerel in the Yellow Sea and East China Sea. 展开更多
关键词 Scomber japonicus environmental factors from remote sensing forecasting model of fishing ground Yellow Sea and East China Sea
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Dynamic Behavior and Deformation Analysis of the Fish Cage System Using Mass-Spring Model 被引量:5
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作者 Chun Woo LEE Jihoon LEE Subong PARK 《China Ocean Engineering》 SCIE EI CSCD 2015年第3期311-324,共14页
Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being c... Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being cultivated. Structural durability of the system against environmental factors has been major concern for the marine aquaculture system. In this research, a mathematical model and a simulation method were presented for analyzing the performance of the large-scale fish cage system influenced by current and waves. The cage system consisted of netting, mooring ropes, floats, sinkers and floating collar. All the elements were modeled by use of the mass-spring model. The structures were divided into finite elements and mass points were placed at the mid-point of each element, and mass points were connected by springs without mass. Each mass point was applied to external and internal forces, and total force was calculated in every integration step. The computation method was applied to the dynamic simulation of the actual fish cage systems rigged with synthetic fiber and copper wire simultaneously influenced by current and waves. Here, we also tried to find a relevant ratio between buoyancy and sinking force of the fish cages. The simulation results provide improved understanding of the behavior of the structure and valuable information concerning optimum ratio of the buoyancy to sinking force according to current speeds. 展开更多
关键词 fish cage mathematical model aquaculture computer simulation mass-spring model
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Interaction model of artificial fish in virtual environment 被引量:2
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作者 Meng Xiangsong Ban Xiaojuan Yin Yixin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期982-987,共6页
Conventional artificial fish has some shortages on the interaction with environment, other fish, and the animator. This article proposes a multi-tier interaction control model of artificial fish, realizes the interact... Conventional artificial fish has some shortages on the interaction with environment, other fish, and the animator. This article proposes a multi-tier interaction control model of artificial fish, realizes the interaction model through integration of virtual reality technology and Markov sequence, and provides a virtual marine world to describe the interaction between artificial fish and the virtual environment and the interaction between the artificial fish and the animator. Simulation results show that the interaction model owns not only the basic characteristics of virtual biology, but also has high trueness interaction function. 展开更多
关键词 artificial life artificial fish interaction model Markov sequence.
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Linking Fish Habitat Modelling and Sediment Transport in Running Waters
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作者 Andreas EISNER Silke WIEPRECHT Matthias SCHNEIDER 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2005年第S1期52-56,共5页
The assessment of ecological status for running waters is one of the major issues within an integrated river basin management and plays a key role with respect to the implementation of the European Water Frame- work D... The assessment of ecological status for running waters is one of the major issues within an integrated river basin management and plays a key role with respect to the implementation of the European Water Frame- work Directive (WFD).One of the tools supporting the development of sustainable river management is physi- cal habitat modeling,e.g.,for fish,because fish population are one of the most important indicators for the e- colngical integrity of rivers.Within physical habitat models hydromorphological ... 展开更多
关键词 MORPHODYNAMICS sediment transport fish habitat modeling fuzzy logic CASIMIR
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Constructing the Ontology for Modeling the Fish Production in Pearl River Basin 被引量:2
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作者 HE Qi-yun ZHENG Ye-lu XU Jian-ning 《Journal of Integrative Agriculture》 SCIE CSCD 2012年第5期760-768,共9页
This paper puts forward a construction method based on ontology for the Pearl River Basin fish production, to facilitate the domain knowledge analysis and information retrieval. By converting the concepts and terms in... This paper puts forward a construction method based on ontology for the Pearl River Basin fish production, to facilitate the domain knowledge analysis and information retrieval. By converting the concepts and terms in domain ordinally, the fish production ontology was constructed with the definition of classes, properties, instances, and relationships. The developed ontology model of the fish production knowledge is proposed and applied in the system of fish diseases diagnosis primarily. The research lays the semantic foundation for the further efficient knowledge management and practical application. 展开更多
关键词 fish production knowledge ONTOLOGY modelING the Pearl River Basin
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STUDY ON RESIDUES OF ^(14)C-CARBOFURAN IN MODEL RICE-FISH ECOSYSTEM
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作者 张仲良 王化新 +3 位作者 任光璪 郭大智 吴素琼 陈志瑜 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第1期42-47,共6页
Residues of 14C- carbofuran were studied in model late- rice ecosystem (LRE) and early- rice ecosystem (ERE). The treatment consisted of two rates of the pesticide (1x) and 2.5x). At day 56 after application, 7.3% (1x... Residues of 14C- carbofuran were studied in model late- rice ecosystem (LRE) and early- rice ecosystem (ERE). The treatment consisted of two rates of the pesticide (1x) and 2.5x). At day 56 after application, 7.3% (1x) and 2.9% (2.5x) of the pesticide and its degradative products remained in the water of the LRE, and 1.8% (1x) and 2.4% (2.5x) of them remained in the water of the ERE. At harvest, 37.5% (LRE) and 24.0% (ERE) of the pesticide applied were detected in the upper layer of the soil; and 40.6% (LRE) and 26.9% (ERE) remained in the lower layer of the soil. The residues in the rice plants increased at the first stage, reached maximum levels during day 14 to 28 after application, and decreased thereafter. At harvest, residues in the stems and leaves in the two treatments (1x and 2.5x) were 3.91μ g/g and 7.78μ g/g (LRE) and 5.04 μg/g and 17.29 μ g/g (ERE) respectively. Residues in the ears were about 1/8 to 1/12 of that in the other parts of the plants. The pesticide residues in fish bodies in both experiments were also determined. 展开更多
关键词 CARBOFURAN Residue model rice- fish ECOSYSTEM
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Dynamic Analysis of an Algae-Fish Harvested Model with Allee Effect
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作者 Xiaoyu Song Hengguo Yu Min Zhao 《Journal of Applied Mathematics and Physics》 2023年第10期2938-2962,共25页
In this paper, an algae-fish harvested model with Allee effect was established to further explore the dynamic evolution mechanism under the influence of key factors. Mathematical theoretical work not only investigated... In this paper, an algae-fish harvested model with Allee effect was established to further explore the dynamic evolution mechanism under the influence of key factors. Mathematical theoretical work not only investigated the existence and stability of all possible equilibrium points, but also probed into the occurrence of transcritical and Hopf bifurcation. The numerical simulation works verified the effectiveness of the theoretical derivation results and displayed rich bifurcation dynamical behaviors, which showed that Allee effect and harvest have played a vital role in the dynamic relationship between algae and fish. In summary, it was expected that these research results would be beneficial for promoting the study of bifurcation dynamics in aquatic ecosystems. 展开更多
关键词 Algae and fish model Allee Effect HARVESTING Equilibrium Point BIFURCATION
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THE FATE OF ^(14)C-FENITROTHION IN RICE-FISH MODEL ECOSYSTEM
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作者 孙锦荷 甘剑英 李兴明 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第4期243-248,共6页
The fate of fenitrothion in rice- fish ecosystem was studied using C- fenitrothion (14C- F) labelled at methoxyl and two application rates. The fenitrothion in water disappeared quickly, only 8 and 11 ppb in two treat... The fate of fenitrothion in rice- fish ecosystem was studied using C- fenitrothion (14C- F) labelled at methoxyl and two application rates. The fenitrothion in water disappeared quickly, only 8 and 11 ppb in two treatments at harvest were detected respectively. Most of 14C-F in soil existed in upper layer and that in plants appeared in shoots. The extractable residues in cargo rice were 0.36 and 0.58 ppm in two treatments respectively. 14C- residues (14C- R) were concentrated in bones, next viscera, meat and scales. Total 14C-R in meat were 0.92 and 1.77 ppm at harvest. Comparing two treatments, the residue dynamics of fenitrothion in water, soil, plants and fish were similar. 14C- R in water and soil after harvest affected the rice- fish ecosystem in the next season. However, the extractable 14C- R in cargo rice, soil and water were very low. Fenitrothion 14C- fenitrothion Rice- fish Model 展开更多
关键词 FENITROTHION (14)~C- FENITROTHION Rice- fish model ECOSYSTEM
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Spatio-Temporal Variations in Co-Occurrence Patterns of Fish Communities in Haizhou Bay, China: Null Model Analysis 被引量:1
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作者 WANG Jiao ZHANG Chongliang +3 位作者 XUE Ying CHEN Yong REN Yiping XU Binduo 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第6期1497-1506,共10页
Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patte... Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patterns of fish species were examined using the C-score under fixed-fixed null model for fish communities in spring and autumn over different years in the Haizhou Bay,China.The results showed that fish assemblages in the whole bay had non-random patterns in spring and autumn over different years.However,the fish co-occurrence patterns were different for the northern and southern fish assemblages in spring and autumn.The northern fish assemblage showed structured pattern,whereas the southern assemblage were randomly assembled in spring.The co-occurrence patterns of fish communities were relatively stable over different years,and the number of significant species pairs in northern assemblage was more than that in the southern assemblage.Environmental heterogeneity played an important role in determining the distributions of fish species that formed significant species pairs,which might affect the co-occurrence patterns of northern and southern assemblages further in the Haizhou Bay. 展开更多
关键词 fish COMMUNITY Haizhou BAY NULL model analysis SPECIES CO-OCCURRENCE pattern
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Research on Development Models of Ocean Recreational Fishery in Shandong Province
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作者 Zhiwen DONG Fengning WU 《Asian Agricultural Research》 2013年第6期34-36,共3页
Developing recreational fishery is the main way to promote the fisherman transferring their jobs,to enhance their incomes,and to promote the development of the fishing village. The development models of ocean recreati... Developing recreational fishery is the main way to promote the fisherman transferring their jobs,to enhance their incomes,and to promote the development of the fishing village. The development models of ocean recreational fishery of Shandong province were given. According to the development of recreational fishery and management models,the development modes of recreational fisheries can be divided as: individual operation mode,fishermen association mode,the company and fishermen joint venture mode,the government leading mode and enterprises synergetic mode. The new direction of recreational fishery was pointed out at last. 展开更多
关键词 OCEAN RECREATIONAL fishERY SHANDONG PROVINCE fishi
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High Yield and Efficient Cultivation Techniques of Rice under Rice- fish Intergrowth Model in Chengdu
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作者 Liangyu LI Shun HE +6 位作者 Hong TANG Xia CHEN Ma YANG Xiaoli ZHANG Jian CHEN Jiaxing LIU WenyanWEI 《Asian Agricultural Research》 2018年第3期76-77,共2页
The integrated planting and breeding of paddy fields is a kind of eco-planting and breeding mode which makes rice and aquatic animals benefit from each other,greatly reducing the harm of rice pests and diseases,using ... The integrated planting and breeding of paddy fields is a kind of eco-planting and breeding mode which makes rice and aquatic animals benefit from each other,greatly reducing the harm of rice pests and diseases,using less or even no fertilizers or pesticides,greatly reducing the agricultural non-point source pollution,thus achieving the " multiple use of water,multiple harvests in one field,grain and fishing winwin,ecological and high efficient use. " In this paper,the high yield and efficient cultivation techniques of rice under the rice-fish intergrowth model in Chengdu was introduced from the aspects of selecting good paddy fields for fishing,using appropriate rice varieties,soaking disinfection,timely sowing and nurturing strong seedlings,reasonable close planting,reasonable fertilization,scientific water management,scientific pest control and rice harvests. 展开更多
关键词 Rice-fish intergrowth model RICE High yield and high efficiency cultivation techniques Chengdu area
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Use of Acellular Fish Skin for Dura Repair in an Ovine Model: A Pilot Study 被引量:1
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作者 Hilmar Kjartansson Ingvar Hakon Olafsson +5 位作者 Sigurbergur Karason Hjalti Thorisson Baldur Tumi Baldursson Eggert Gunnarsson Einar Jorundsson Gudmundur Fertram Sigurjonsson 《Open Journal of Modern Neurosurgery》 2015年第4期124-136,共13页
Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis... Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis Omega3 DuraTM). In an ovine model a craniotomy under general anaesthesia was performed. A defect was produced in the dural covering of approximately 1 × 2 cm and closed with an onlay technique, with Kerecis Omega3 Dura. The bone defect was covered with the bony flap and the overlying tissues closed in layers. At 2, 5, 8 and 11 weeks the sheep underwent MRI scanning followed by euthanasia, necropsy and histological assessment. MRI images taken at 2, 5, 8 and 11 weeks showed initially moderate inflammatory response, which diminished over time, and at 11 weeks no evidence of inflammation existed. There was evidence of cerebrospinal fluid leakage at no time point. Necropsy revealed some adhesions at 5 and 8 weeks, in particular at 5 weeks, but at 11 weeks there were no adhesions found. From 2 - 11 weeks, there was evidence of initially an inflammatory reaction followed by neodura formation at the defect site through cellular ingrowth and remodeling of the acellular fish skin. Histology showed a histiocytic foreign body reaction initially that subsided over time. As early as 8 weeks there was evidence of neodura formation and by 11 weeks there was a minimal inflammatory response with an intact neodura formed. In this pilot study the Kerecis Omega3 Dura patches performed in a safe and efficacious manner. This new material needs to be fully assessed and compared with other products that are currently on the market in a larger scale animal study. 展开更多
关键词 Duraplasty DURA REPAIR Piscine ACELLULAR Dermal GRAFT Neurosurgery DURA Mater fish SKIN GRAFT ACELLULAR fish SKIN Craniotomy Ovine model Dural Defect
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Reduced Life Expectancy Model Analyses of Exposure Time Effects of Endocrine Disruptors to Teleost Fishes Based on Effect Concentration of Hepatic Biomarkers
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作者 Mengtian Sun Hualong Chen Ling Zhao 《Journal of Environmental Protection》 2020年第7期540-550,共11页
In this current paper, the exposure time effects on four endocrine disruptors and teleost fishes were evaluated using the reduced life expectancy (RLE) model based on the effect concentration (EC<sub>50</sub&... In this current paper, the exposure time effects on four endocrine disruptors and teleost fishes were evaluated using the reduced life expectancy (RLE) model based on the effect concentration (EC<sub>50</sub>) of available literature published. The result on the regression analysis over different exposure times has demonstrated that the EC<sub>50</sub> of hepatic biomarkers falls with increasing exposure times in a predictable manner. The slopes of the regression equations reflect the strength of the toxic effects on the various teleost fish. The EC<sub>50</sub> reduction over time can be interpreted based on the bioconcentration process, which can be used to understand transfer routes of the compounds from water to fish body. RLE model also provides useful information in assessing the toxic effects on fish life expectancy as a result of the occurrence of compounds. 展开更多
关键词 Reduced Life Expectancy model Endocrine Disruptors Effect Concentration Hepatic Biomarkers Teleost fishes
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基于T细胞效应的多机器鱼环境免疫协作探测
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作者 江亚峰 王舜 +2 位作者 张亮 刘维 袁明新 《舰船科学技术》 北大核心 2025年第4期154-162,共9页
为提高多机器鱼在未知复杂水域中的探测质量和效率,提出了基于T细胞效应的环境免疫协作探测模型和算法。首先基于Jerne的独特型免疫网络假设构建多机器鱼基本免疫协作探测网络模型;然后根据已探测区域的环境信息,借鉴生物T细胞效应,构... 为提高多机器鱼在未知复杂水域中的探测质量和效率,提出了基于T细胞效应的环境免疫协作探测模型和算法。首先基于Jerne的独特型免疫网络假设构建多机器鱼基本免疫协作探测网络模型;然后根据已探测区域的环境信息,借鉴生物T细胞效应,构建多机器鱼的互联耦合免疫协作探测网络模型;最后进行算法设计和实验测试。实验结果表明,与基于免疫机理的完全探测算法和基于生物熵的免疫协作探测算法相比,文中算法的覆盖率平均提高了7.6%,重复探测率平均降低了32.8%,平均探测步数平均降低了11.6%,平均重复探测步数平均降低了24.7%,验证了未知复杂环境中多机器鱼互联耦合免疫协作探测网络模型的有效性。 展开更多
关键词 多机器鱼 环境探测 免疫网络模型 独特型免疫网络假设 T细胞效应
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小型模式鱼类在化学品毒理学研究中的应用
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作者 罗丽君 周宇希 +5 位作者 任欣欣 李冰洁 徐志祥 华江环 韩建 周炳升 《水生生物学报》 北大核心 2025年第10期172-195,共24页
化学品的广泛应用在推动社会发展的同时,也带来了严重的环境污染问题,威胁生态环境和人类健康。因此,开展化学品毒理学研究及健康风险评估对实现污染物风险管控具有重要意义。斑马鱼、稀有鮈鲫和青鳉等小型鱼类因其优良的实验动物模型优... 化学品的广泛应用在推动社会发展的同时,也带来了严重的环境污染问题,威胁生态环境和人类健康。因此,开展化学品毒理学研究及健康风险评估对实现污染物风险管控具有重要意义。斑马鱼、稀有鮈鲫和青鳉等小型鱼类因其优良的实验动物模型优势,以及与哺乳动物的高度保守性,已成为环境毒理学研究的重要模型。文章综述了小型模式鱼类在化学品毒理学研究领域的应用进展,包括标准化毒性测试体系,毒代动力学与生物富集研究,以及多层次的毒性效应与机制研究,重点涵盖胚胎发育、代谢紊乱、神经行为、内分泌干扰、心血管功能、免疫和生殖毒性等领域。同时分析了当前研究的不足与局限性,并展望了未来发展方向,以促进小型模式鱼类在毒理学领域的更广泛应用与发展。 展开更多
关键词 小型模式鱼类 化学品 毒性测试 毒理学 风险评价
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基于LeMaRns模型的热带中西太平洋中上层生态系统动态分析
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作者 张春月 林琴琴 +2 位作者 陈作志 朱江峰 李秀超 《水产学报》 北大核心 2025年第3期73-85,共13页
【目的】热带中西部太平洋渔业资源丰富,是全球主要的金枪鱼渔业作业区域。为了解长期捕捞对中西太平洋中上层生态系统的影响,拟建立基于体长结构的生态系统模型LeMaRns,以模拟分析金枪鱼渔业对常见鱼种和生态指标的影响。【方法】设计F... 【目的】热带中西部太平洋渔业资源丰富,是全球主要的金枪鱼渔业作业区域。为了解长期捕捞对中西太平洋中上层生态系统的影响,拟建立基于体长结构的生态系统模型LeMaRns,以模拟分析金枪鱼渔业对常见鱼种和生态指标的影响。【方法】设计F=0(无捕捞活动)、F=Fmsy(最大可持续产量时的捕捞死亡率)、F=F_(recent)(最近几年的平均捕捞死亡率)、F=0.8F_(msy)和F=1.2Fmsy等5种捕捞策略对10个物种进行模拟捕捞,对资源状况进行10年预测。重点分析5种捕捞策略对生物量(B)、产卵群体生物量(SSB)等2个单鱼种指标以及大型鱼类指数(LFI)、平均最大长度(MML)、典型长度(TyL)、体长分位数(LQ)等4个生态指标的影响。【结果】在无捕捞情况下(F=0),物种的生物量基本趋于平衡;在捕捞情况下,大眼金枪鱼、剑鱼、黄鳍金枪鱼、鲣和长鳍金枪鱼等金枪鱼类的生物量下降0.26%~99.75%;灰鲭鲨、平鳍旗鱼、印度枪鱼的生物量上升0.01%~12.51%;大青鲨的生物量上升36.74%,产卵群体生物量下降60%,其余物种的资源状况几乎无变化。在模拟捕捞的前6年,MML、TyL、LQ随着捕捞努力量的增大而增大,之后随着捕捞努力量的增大而减小;LFI随着捕捞努力量的增大未呈现下降趋势。【结论】在当前捕捞强度下,热带中西太平洋生态系统未来10年中处于可持续状态。LeMaRns模型可用于分析大范围的海洋生态系统,为渔业管理提供基于生态系统的分析手段。 展开更多
关键词 渔业管理 LeMaRns模型 捕捞策略 生态系统 生态指标 中西太平洋
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混合渔业视角下舟山渔场几种渔具管理策略对经济物种产量及生物群落影响评估 被引量:2
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作者 赵函磊 王洋 +1 位作者 张畅 王迎宾 《水生生物学报》 北大核心 2025年第4期129-141,共13页
为了探究混合渔业中不同捕捞渔具捕捞努力量变化对渔业活动经济效益及生态效益带来的潜在影响,研究根据2022年在舟山渔场作业的4种渔船的渔捞日志数据,构建舟山渔场质量谱模型(Size Spectrum Model,SSM),评估了混合渔业中各作业方式捕... 为了探究混合渔业中不同捕捞渔具捕捞努力量变化对渔业活动经济效益及生态效益带来的潜在影响,研究根据2022年在舟山渔场作业的4种渔船的渔捞日志数据,构建舟山渔场质量谱模型(Size Spectrum Model,SSM),评估了混合渔业中各作业方式捕捞变化对各物种产量、生物量和生物群落结构的影响。研究通过对13种渔具管理场景进行模拟,分析不同场景下各物种产量的年际变化趋势,并结合群落总生物量、大型鱼类指数、平均体重、平均最大体重和质量谱斜率5种群落生态指标监测群落对不同捕捞活动水平的响应。结果显示:(1)当拖网捕捞努力量下降时,群落总生物量、平均体重及大型鱼类资源量明显上升,银鲳(Pampus argenteus)、黑鮟鱇(Lophiomus setigerus)和大黄鱼(Larimichthys crocea)资源量有所回升,黑鮟鱇和大黄鱼产量显著提高;(2)张网捕捞努力量下降会使群落总生物量有所上升,海鳗(Muraenesox spp.)、棘头梅童(Collichthys lucidus)和带鱼(Trichiurus lepturus)资源量有所回升,海鳗产量显著提高。相反,当张网捕捞努力量上升时,棘头梅童生物量资源及产量逐年下降;(3)当拖虾网捕捞努力量下降时,总产量及群落总生物量有所下降,管鞭虾(Solenocera spp.)和大黄鱼资源量有所回升。而当拖虾网捕捞努力量上升,总产量及群落总生物量有所上升;(4)刺网捕捞努力量变化对于渔业产量、生物量及群落结构影响较小。研究结果对于保护舟山渔场各经济物种资源可持续利用及制定可行和更有效的渔业管理策略提供参考。 展开更多
关键词 混合渔业 舟山渔场 质量谱模型 捕捞努力量 渔业产量
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电磁弯曲驱动器的结构设计与实验研究
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作者 林澳敏 丁建宁 程广贵 《机电工程》 北大核心 2025年第9期1771-1780,共10页
针对目前柔性驱动器存在响应速度和使用安全性无法兼顾的问题,将电磁驱动技术应用于驱动器的设计中,设计了一种环状电磁弯曲驱动器。首先,对驱动器的整体结构进行了设计,分析了驱动原理并制定了制备步骤,通过添加环形限制结构,实现了驱... 针对目前柔性驱动器存在响应速度和使用安全性无法兼顾的问题,将电磁驱动技术应用于驱动器的设计中,设计了一种环状电磁弯曲驱动器。首先,对驱动器的整体结构进行了设计,分析了驱动原理并制定了制备步骤,通过添加环形限制结构,实现了驱动器马鞍形弯曲变形目的;然后,通过结构简化,建立了电磁弯曲驱动器的分析模型,探究了影响驱动器弯曲角度的关键参数;接着,搭建了驱动器的实验控制平台,测试了驱动器的响应速度,验证了关键参数对弯曲角度的影响,并探究了弯曲角度与电压的关系;最后,基于电磁弯曲驱动器设计了一款机器鱼,并控制机器鱼向前游动以验证驱动器驱动机器鱼的可行性。研究结果表明:电磁弯曲驱动器的驱动电压低于36 V,响应时间小于50 ms;能达到的最大弯曲角度受到电源电压、电磁线圈覆盖比以及液体填充体积比的影响;通过周期性地施加电压可以驱动机器鱼直线游动,在36 V、8 Hz的输入信号下,机器鱼直线游动的平均速度达到10.37 cm/s,验证了驱动器驱动该机器鱼的可行性。 展开更多
关键词 柔性驱动器 电磁驱动 响应速度 结构设计 力学模型 机器鱼
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