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A mass balanced model of trophic structure and energy flows of a semi-closed marine ecosystem

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Acta Oceanologica Sinica 2017年第10期36卷 60-69页

作者： han dongyan XUE Ying ZhanG Chongliang REN Yiping Fisheries College Ocean University of China

The marine ecosystem of the Jiaozhou Bay has degraded significantly in fisheries productivity and its ecological roles as spawning and nursery ground for many species of commercial importance has been declining in recent years. A mass-balanced trophic model was developed using Ecopath with Ecosim to evaluate the trophic structure of the Jiaozhou Bay for improving ecosystem management. The model were parameterized based on the fisheries survey data in the Jiaozhou Bay in 2011, including 23 species groups and one detritus group according to their ecological roles. The trophic levels of these ecological groups ranged from 1（primary producers and detritus） to4.3（large demersal fishes）. The estimated total system throughput was 12 917.10 t/（km^2·a）, with 74.59% and25.41% contribution of the total energy flows from phytoplankton and detritus, respectively. Network analyses showed that the overall transfer efficiency of the ecosystem was 14.4%, and the mean transfer efficiency was 14.5%for grazing food chain and 13.9% for detritus food chain. The system omnivory index（SOI）, Finn＇s cycled index（FCI） and connectance index（CI） were relatively low in this area while the total primary production/total respiration（TPP/TR） was high, indicating an immature and unstable status of the Jiaozhou Bay ecosystem. Mixed trophic impact analysis revealed that the cultured shellfish had substantial negative impacts on most functional groups. This study contributed to ecosystem-level evaluation and management planning of the Jiaozhou Bay ecosystem.

关键词： Ecopath with Ecosim Jiaozhou Bay energy flow trophic structure

Impacts of sample size for stomach content analysis on the estimation of ecosystem indices

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Acta Oceanologica Sinica 2020年第8期39卷 53-61页

作者： dongyan han Chongliang Zhang Ying Xue Binduo Xu Yiping Ren Yong Chen College of Fisheries Ocean University of ChinaQingdao 266003China School of Marine Sciences University of MaineOronoMaine 04469USA Laboratory for Marine Fisheries Science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

This study used Ecopath model of the Jiaozhou Bay as an example to evaluate the effect of stomach sample size of three fish species on the projection of this model. The derived ecosystem indices were classified into three categories:(1) direct indices, like the trophic level of species, influenced by stomach sample size directly;(2)indirect indices, like ecology efficiency(EE) of invertebrates, influenced by the multiple prey-predator relationships;and(3) systemic indices, like total system throughout(TST), describing the status of the whole ecosystem. The influences of different stomach sample sizes on these indices were evaluated. The results suggest that systemic indices of the ecosystem model were robust to stomach sample sizes, whereas specific indices related to species were indicated to be with low accuracy and precision when stomach samples were *** indices became more uncertain when the stomach sample sizes varied for more species. This study enhances the understanding of how the quality of diet composition data influences ecosystem modeling outputs. The results can also guide the design of stomach content analysis for developing ecosystem models.

关键词： computer simulation Ecopath with Ecosim ecosystem index optimization sample size stomach contents analysis

Impacts of El Nino on the somatic condition of Humboldt squid based on the beak morphology

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Journal of Oceanology and Limnology 2019年第4期37卷 1440-1448页

作者： HU Guanyu YU Wei LI Bai han dongyan CHEN Xinjun CHEN Yong LI Jianhua College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China National Distant-water Fisheries Engineering Research Center Shanghai Ocean UniversityShanghai 201306China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China School of Marine Sciences University of MaineOronoMaine 04469USA Collaborative Innovation Center for National Distant-water Fisheries Shanghai 201306China College of Fisheries Ocean University of ChinaQingdao 266003China

The Humboldt squid Dosidicus gigas has a short life span, and environmental variability plays a significant role in regulating its population dynamics and distribution. An analysis of 1 096 samples of D. gigas collected by the Chinese commercial fishing vessels during 2013, 2014, and 2016 off the Peruvian Exclusive Economic Zone, was conducted to evaluate the impacts of El Nino events on the somatic condition of D. gigas. This study indicates that the slopes of all beak variables in relation to mantle length (ML) for females were greater than those of males during 2013, 2014, and 2016, and slopes of the upper crest length and the lower rostrum length significantly differed between females and males in 2013 (P0.05). The Fulton's condition coefficients (K) of females and males in 2013 and 2014 were significantly greater than those in 2016 (Phan those of males in 2013, 2014, and 2016, and K values significantly differed between females and males in 2013. In normal years, the chlorophyll a (Chl a) concentration showed an N-shaped variability from January to December. However, in the El Nino period, it tended to weaken the upwelling coupled with warm and low Chl a concentration waters. We suggest that the poor somatic condition of D. gigas during the El Nino year was resulted from the low Chl a concentration in the waters, and the abundance of D. gigas would decrease due to the unfavourable environment and the lack of prey items in the El Nino year.

关键词： El Nino event Dosidicus gigas somatic condition abundance beak morphology

Beak Measurements of Octopus (Octopus variabilis) in Jiaozhou Bay and Their Use in Size and Biomass Estimation

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Journal of Ocean University of China 2013年第3期12卷 469-476页

作者： XUE Ying REN Yiping MENG Wenrong LI Long MAO Xia han dongyan MA Qiuyun Fisheries College Ocean University of China Oceanic and Fishery Administration of Lianyun District Nantong Station Regional Bureau of East China Sea Fishery ManagementMinistry of Agriculture of China

Cephalopods play key roles in global marine ecosystems as both predators and *** estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding ecology of predators at higher trophic *** this study,regressive relationships among beak measurements and body length and weight were determined for an octopus species(Octopus variabilis),an important endemic cephalopod species in the northwest Pacific Ocean.A total of 193 individuals(63 males and 130 females) were collected at a monthly interval from Jiaozhou Bay,*** relationships among 6 beak measurements(upper hood length,UHL;upper crest length,UCL;lower hood length,LHL;lower crest length,LCL;and upper and lower beak weights) and mantle length(ML),total length(TL) and body weight(W) were *** showed that the relationships between beak size and TL and beak size and ML were linearly regressive,while those between beak size and W fitted a power function *** and UCL were the most useful measurements for estimating the size and biomass of *** relationships among beak measurements and body length(either ML or TL) were not significantly different between two sexes;while those among several beak measurements(UHL,LHL and LBW) and body weight(W) were sexually *** male individuals of this species have a slightly greater body weight distribution than female individuals,the body weight was not an appropriate measurement for estimating size and biomass,especially when the sex of individuals in the stomachs of predators was *** relationships provided essential information for future use in size and biomass estimation of ***,as well as the estimation of predator/prey size ratios in the diet of top predators.

关键词： Octopus variabilis Jiaozhou Bay beak measurement body size hood length crest length

喷涂频率对车用316L钢表面等离子Mo-Al膜摩擦性能的影响

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真空科学与技术学报 2020年第6期40卷 550-554页

作者：贾爱芹韩东艳黄河交通学院汽车工程学院焦作454950 黄河科技学院交通学院郑州450000

以车用316L不锈钢作为基材,对其实施等离子喷涂处理使其表面生成Mo-Al膜,分析表面温度变化、电弧特征以及形成的磨痕特点,对比了不同喷涂频率下得到的膜载流摩擦磨损特性。研究结果表明:当频率20 Hz时,在磨痕的表面区域形成了一层具有... 详细信息

以车用316L不锈钢作为基材,对其实施等离子喷涂处理使其表面生成Mo-Al膜,分析表面温度变化、电弧特征以及形成的磨痕特点,对比了不同喷涂频率下得到的膜载流摩擦磨损特性。研究结果表明:当频率20 Hz时,在磨痕的表面区域形成了一层具有均匀尺寸的磨粒。元素分布表明Al元素发生了少量转移,跟膜层组织成分较为接近。在频率20 Hz下形成了具有完整结构的摩擦膜,此时在表面区域形成了尺寸均匀的磨粒。提高喷涂频率后,会引起摩擦副的大幅冲击并发生明显震动,温度迅速上升,更易发生氧化。当提高喷涂频率后,摩擦系数以及磨损率都发生了先减小再升高的变化规律,转折点在喷涂频率20 Hz,此时取值分别为0.326和68.5。

关键词：等离子喷涂 Mo-Al膜喷涂频率摩擦系数磨损率

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技工院校物流管理专业核心技能评价体系研究

物流技术 2013年第12期32卷 479-482页

作者：韩冬艳深圳第二高级技工学校广东深圳518017

根据技工院校物流管理专业的特点,评价体系首先构建其核心技能的各层级指标,接着调研统计相应的技能指标权重,然后分析物流管理专业学生所掌握的核心技能,最后提出学生的实习就业方向和职业规划。

关键词：物流管理核心技能评价体系

I-ECAP挤压对汽车散热器用MnE21镁合金性能的影响

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热加工工艺 2018年第3期47卷 140-143页

作者：韩东艳贾爱芹黄河科技学院交通学院

采用不同的挤压工艺进行了汽车散热器用Mn E21镁合金板材试样的成形,并进行了试样力学性能和耐腐蚀性能的测试与分析。结果表明：与常规挤压相比,I-ECAP挤压可以提高试样力学性能和耐腐蚀性能。Mn E21镁合金板材成形优选I-ECAP挤压工艺... 详细信息

采用不同的挤压工艺进行了汽车散热器用Mn E21镁合金板材试样的成形,并进行了试样力学性能和耐腐蚀性能的测试与分析。结果表明：与常规挤压相比,I-ECAP挤压可以提高试样力学性能和耐腐蚀性能。Mn E21镁合金板材成形优选I-ECAP挤压工艺。与常规挤压优化工艺相比,I-ECAP挤压能增大抗拉强度12 MPa、屈服强度9 MPa、腐蚀电位正移22 m V。

关键词： Mn E21镁合金汽车散热器挤压工艺力学性能耐腐蚀性能增量等通道角挤压

热处理工艺对车用半固态Mg-5.5Zn-0.1Y镁合金微观组织演变的影响

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热加工工艺 2019年第14期48卷 163-166页

作者：贾爱芹韩东艳黄河交通学院汽车工程学院河南焦作454950 黄河科技学院交通学院河南郑州450000

选择Mg-Zn二元合金作为研究对象,在该合金中加入第三组元Y,制备得到Mg-5.5Zn-0.1Y镁合金,对该试样进行热处理,并分析了Mg-5.5Zn-0.1Y镁合金组织结构特征与保温温度及时间的关系,从而获得最优热处理工艺。结果表明:铸态Mg-5.5Zn-0.1Y合... 详细信息

选择Mg-Zn二元合金作为研究对象,在该合金中加入第三组元Y,制备得到Mg-5.5Zn-0.1Y镁合金,对该试样进行热处理,并分析了Mg-5.5Zn-0.1Y镁合金组织结构特征与保温温度及时间的关系,从而获得最优热处理工艺。结果表明:铸态Mg-5.5Zn-0.1Y合金中形成了α-Mg基体以及呈现沿晶分布特点的共晶组织。随着保温温度上升至620℃后,颗粒尺寸与形状因子都到达最小,依次等于48.3μm与1.24。随着保温温度的不断提高,在晶界处形成的共晶组织重熔转变为颗粒状组织。620℃热处理随着保温时间到达40min时,组织中的颗粒尺寸变为最小,48.3μm,并且分布形态也更加均匀,此时的固相率是52.2%。确定最佳的半固态Mg-5.5Zn-0.1Y镁合金热处理参数为620℃,40min。

关键词： Mg-5.5Zn-0.1Y镁合金半固态等温处理组织

固溶温度对车用7B04铝合金板材组织和力学性能的影响

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热加工工艺 2018年第24期47卷 215-217页

作者：韩东艳朱镜瑾黄河科技学院交通学院河南郑州450000 黄河交通学院汽车工程学院河南焦作454900

采用扫描电子显微镜和拉伸力学性能测试合金的微观组织和性能,研究不同固溶温度对7B04铝合金板材微观组织和力学性能的影响。结果表明:铝合金在450℃温度下固溶处理后还有许多未溶解的细小颗粒。随着固溶温度增加,没有溶解的组织是难溶... 详细信息

采用扫描电子显微镜和拉伸力学性能测试合金的微观组织和性能,研究不同固溶温度对7B04铝合金板材微观组织和力学性能的影响。结果表明:铝合金在450℃温度下固溶处理后还有许多未溶解的细小颗粒。随着固溶温度增加,没有溶解的组织是难溶的富Fe/Mn相;铝合金在475℃温度固溶处理后其晶粒平均尺寸约为2μm。随着固溶处理温度增加,板材的硬度与密度逐渐减低。固溶温度为475℃时铝合金板材性能达到最佳,其抗拉强度、屈服强度和伸长率分别为256 MPa、188 MPa和4.2%。此时,断口区生成众多韧窝与撕裂棱,断裂形式属于韧性断裂。

关键词： 7B04铝合金板材固溶处理力学性能