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71.
Préau Clémentine Dubos Nicolas Lenormand Maxime Denelle Pierre Le Louarn Marine Alleaume Samuel Luque Sandra 《Landscape Ecology》2022,37(3):729-743
Landscape Ecology - Prioritising is likely to differ depending on the species considered for connectivity assessments, leading to a lack of consensual decisions for territorial planning. The... 相似文献
72.
73.
渔船型线计算机辅助设计模型及软件系统的研究 总被引:2,自引:1,他引:2
本文重点讨论了在计算机辅助渔船型线设计中采用的数学模型,应用数据库技术生成和逐渐完善母型船的型船库系统,以及采用三次样条函数插值解决光顺问题和软件系统。 相似文献
74.
智利外海茎柔鱼繁殖生物学初步研究 总被引:1,自引:0,他引:1
对2007年-2009年我国鱿钓船在东南太平洋智利外海生产期间所采集的1 374个茎柔鱼样品性成熟度进行观察,初步研究了其繁殖生物学特性。结果表明:智利外海茎柔鱼为大型群体,常年产卵,无明显的产卵高峰期。渔获物雌雄比例约为2.65∶1。雌、雄个体性腺成熟度差异不明显,其中成熟个体所占比例小,分别占总量的3.9%和6.7%。缠卵腺长和缠卵腺重随着性腺成熟度增加逐步增大,成熟个体性腺指数明显大于未成熟个体。雌、雄个体性腺指数存在差异,雌性个体Ⅳ期性腺指数与胴长成正比,而雄性则成反比。雌性和雄性茎柔鱼的初次性成熟胴长(ML50%)分别为638.3 mm和565.3 mm。 相似文献
75.
方形人工鱼礁单体流场效应的PIV试验研究 总被引:2,自引:0,他引:2
采用粒子图像测速(PIV)二维流场测速技术和水槽模拟试验研究了人工鱼礁的流场效应,对单体开口比分别为0、0.04、0.16、0.25的人工鱼礁在来流流速分别为67、112、180 mm/s时产生的流场效应进行分析.结果表明:单体人工鱼礁流场效应中,开口比和来流流速均对流场效应产生影响,开口比越小,来流流速越大,流场中的上升流流速和背涡流面积就越大.研究表明,影响流场效应的主要因素是开口比,来流流速的影响程度次之. 相似文献
76.
Study on the Quantity Dynamic Changes of Heterobacteria and Vibrios in Larvae Industrialized Culture System 总被引:4,自引:0,他引:4
MA Yan LI Jian WANG Bin WANG Qun LIU Qi. College of Life Sciences Technology Dalian Fisheries University Dalian . Key Laboratory for Sustainable Utilization of Marine Fishery Resources Ministry of Agriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 《(《农业科学与技术》)编辑部》2008,(2)
[Objective] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp.[Method] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system.[Result] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius,then their number would increase with growth. During whole rearing period,both heterobacteria in larvae,vibrios in water would increase by one order of magnitude,while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude.There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait.The correlation coefficients between larvae and heterobacteria and vibrios in water were 0.704 and 0.840 in culture system respectively,while the correlation among heterobacteria,vibrios in living bait and larvae,water were weak or negative.[Conclusion] There was a dynamic relation between water and larvae in rearing period,and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus,besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system. 相似文献
77.
78.
Adam-Berret M Boulard M Riaublanc A Mariette F 《Journal of agricultural and food chemistry》2011,59(5):1767-1773
Model systems composed of tristearin in solid state and tricaprin in liquid state with different solid-fat content (SFC) and storage time have been investigated by relaxation NMR and NMR diffusometry. The T(2) relaxation of the tricaprin in the melt exhibited a bimodal distribution as previously observed. The SFC had a major effect on the T(2) relaxation. This effect was explained according to the fast diffusive exchange model in porous media. According to this model the changes in T(2) relaxation as a function of the SFC and storage time were explained by the decrease of the surface-to-volume ratio of the crystal induced by Ostwald ripening. The diffusion coefficient D of the tricaprin in the melt decreased for higher SFC. Since no significant variation of D was observed for different diffusion time, D reflected the long-range connectivity and the tortuosity was calculated. During storage the diffusion coefficient remained constant. 相似文献
79.
Angelstam Per Manton Michael Elbakidze Marine Sijtsma Frans Adamescu Mihai Cristian Avni Noa Beja Pedro Bezak Peter Zyablikova Iryna Cruz Fatima Bretagnolle Vincent Díaz-Delgado Ricardo Ens Bruno Fedoriak Mariia Flaim Giovanna Gingrich Simone Lavi-Neeman Miri Medinets Sergey Melecis Viesturs Muñoz-Rojas Jose Schäckermann Jessica Stocker-Kiss Andrea Setälä Heikki Stryamets Natalie Taka Maija Tallec Gaelle Tappeiner Ulrike Törnblom Johan Yamelynets Taras 《Landscape Ecology》2019,34(7):1461-1484
Landscape Ecology - Place-based transdisciplinary research involves multiple academic disciplines and non-academic actors. Long-Term Socio-Ecological Research (LTSER) platform is one concept with ~... 相似文献
80.