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1.
基于渔业产业现状,分析国内外在大型渔业平台、深海网箱和养殖工船方面的发展现状,提出“游弋式”养殖工船及深远海渔业的基本概念。受限于投资成本、技术发展水平等客观因素,中国深远海养殖发展速度缓慢,但近年来取得了一定的发展成效。笔者针对现阶段渔业粗放型生产方式的现状,从国家战略、渔业改革和产业需求等角度分析深远海渔业发展的必要性,认为发展以养殖工船为代表的深远海大型渔业平台是实现渔业强国之路的有效途径之一,走出一条符合中国国情的深远海渔业平台的开发之路势在必行。 相似文献
2.
全球变暖会对舟山沿岸上升流的驱动机制产生深远影响,继而作用于海域内的生态环境及渔业资源发生的变迁。使用三维海洋数值模型FVCOM,模拟研究了热通量、风场等气候环境因子变化下舟山沿岸上升流区夏季水动力及环境因子的分布特征。通过引入跃变检验方法来评估全球变暖对过去三十多年来舟山及其邻近海域的夏季海表温度的影响,发现在2016年前后发生了明显的跃变,跃变后海表温度相对于跃变前升高了约1 °C;热通量分析结果显示春季云量减小,短波辐射增加导致的海水热含量增加是夏季海水升温的重要原因;风速的时空变化表明舟山海域7月风速在近几十年有减弱的趋势。通过构建气候环境因子变化的敏感性数值模型实验探究了舟山沿岸上升流水动力的演变机制,结果表明海气热通量增加导致的表层海水吸热及平流热输运增加引起的海水层化加强会使得底层海水不易抬升;夏季风应力的减弱削弱了长江冲淡水低盐水舌的离岸扩展,导致上升流区上层海水的层化减弱,从而加强中下层海水向岸爬升,增加沿岸上升流的强度。 相似文献
3.
Kent MORI Satoshi SUZUKI Daisuke KOYABU Junpei KIMURA Sung-Yong HAN Hideki ENDO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):571-578
Although the sea otter (Enhydra lutris) is a complete aquatic species,
spending its entire life in the ocean, it has been considered morphologically to be a
semi-aquatic animal. This study aimed to clarify the unique hindlimb morphology and
functional adaptations of E. lutris in comparison to other Mustelidae
species. We compared muscle mass and bone measurements of five Mustelidae species: the sea
otter, Eurasian river otter (Lutra lutra), American mink
(Neovison vison), Japanese weasel (Mustela itatsi) and
Siberian weasel (M. sibirica). In comparison with the other 4 species,
E. lutris possessed significantly larger gluteus, popliteus and
peroneus muscles, but smaller adductor and ischiopubic muscles. The popliteus muscle may
act as a medial rotator of the crus, and the peroneus muscle may act as an abductor of the
fifth toe and/or the pronator of the foot. The bundles of the gluteus superficialis muscle
of E. lutris were fused with those of the tensor fasciae latae muscle and
gluteofemoralis muscles, and they may play a role in femur abduction. These results
suggest that E. lutris uses the abducted femur, medially rotated crus,
eversion of the ankle and abducted fifth digit or extended interdigital web as a powerful
propulsion generator. Therefore, we conclude that E. lutris is a complete
aquatic animal, possessing differences in the proportions of the hindlimb muscles compared
with those in other semi-aquatic and terrestrial mustelids. 相似文献
4.
海堤边坡几种树种适宜性评价 总被引:1,自引:0,他引:1
为了给海堤绿化及沿海防护林的营建提供科学依据,通过对海堤边坡水分、盐分以及大气等立地因子的综合研究分析,结合海堤边坡造林试验,对杂交柳、紫穗槐、黄金条、刺槐、楝树、铅笔柏6个树种的生长适宜性作出了评价,研究结果表明:(1)海堤边坡土壤属于中度到强度盐渍化土且土壤含水率季节变化大,其中海雾、海风也是海堤立地条件中非常重要... 相似文献
5.
Karen E. Jensen J. Christopher Taylor Robert J. Barry Louis R. D'Abramo D. Allen Davis Stephen A. Watts 《Journal of the World Aquaculture Society》2019,50(3):614-621
Sea urchins produce high‐energy, membrane‐bound fecal pellets that contain residual nutrients and large quantities of microbiota. These egesta are readily consumed by the shrimp, Litopenaeus vannamei. Egesta of the sea urchin, Lytechinus variegatus, were evaluated as a feed supplement or total replacement for a commercial shrimp diet. Shrimp were stocked at 0.49 g ± 0.06 g initial body weight and housed individually in 2.8‐L tanks in a commercial recirculating zebrafish system. Shrimp were assigned to one of six diets: commercial shrimp feed, reference sea urchin feed, collected dried sea urchin egesta, collected wet sea urchin egesta, half ration of shrimp feed and half collected wet sea urchin egesta, and egesta naturally produced by two sea urchins in polyculture. Equivalent dry matter amounts of each diet were proffered to shrimp in each treatment twice daily, except for those that had complete access to natural egesta excreted by sea urchins in polyculture. Sea urchins were proffered a reference sea urchin feed at 2% body weight daily. After 27 days, shrimp proffered collected dried or wet egesta did not differ significantly in percent weight gain and showed the lowest weight gain. The percent weight gain of shrimp fed the commercial shrimp diet did not differ significantly from that of the shrimp fed half commercial shrimp diet and half egesta. The highest weight gain was recorded for those shrimp that consumed the untouched egesta produced by sea urchins in polyculture. These data suggest that consumed egesta have noteworthy nutritional value and therefore would be beneficial to the culture of extractive species in an integrated multitrophic aquaculture system. 相似文献
6.
Weijie Zhang Xiaohui Chen Huijie Jiang Zhong Wang Baofeng Wang Yaoyao Zhan Shoubing Qi Yaqing Chang 《Journal of the World Aquaculture Society》2019,50(5):969-982
To investigate the effects of family, stocking density, and their interaction on mortality, growth rate, and size dispersal in the sea urchin Strongylocentrotus intermedius, 1,440 juveniles from six full‐sib families were exposed to three stocking densities, that is, low stocking density (LD), middle stocking density (MD), and high stocking density (HD), and reared for 10 months in sea‐based suspended cages. The results demonstrated significant family effects on cumulative mortality rate (CMR); specific growth rate for test diameter (SGR for TD); specific growth rate for body weight (SGR for BW); coefficient of variation for body weight at the 10th month (CV for BW10); and significant stocking density effects on SGR for TD, SGR for BW, and CV for BW10. Statistically significant family by stocking density interaction was only found in SGR for TD. A certain degree of family‐ranking inversions occurred in SGR for TD. The present study provides evidence for the existence of family by stocking density interaction on the growth rate of test diameter in the family selection for S. intermedius. More attention should be paid to this interaction effect to select correct parents in S. intermedius. 相似文献
7.
8.
基于非结构有限体积法海洋模型FVCOM,对渤海潮波系统进行数值模拟。利用渤海沿岸共19个潮位站的资料对模拟结果进行验证,计算结果均与实测结果吻合良好。基于此进一步研究渤海3个主要浅水分潮M4、MS4和M6的主要特征,并与前人的研究成果进行对比。结果表明M4和MS4分潮传播特征相似,都存在5个无潮点,其中1个为顺时针旋转,而其余四个为逆时针旋转。对于M6分潮,结果显示存在9个无潮点,两个为顺时针,其余七个为逆时针。M4分潮振幅在近岸处可达25cm,约为M2分潮振幅的10%,MS4振幅次之,M6振幅最小,仅为M4分潮振幅的18%左右。三者振幅均为从外海向近岸迅速增大,表明浅水分潮振幅分布特征与海底地形关系密切。 相似文献
9.
Alexandra S. Silchenko Anatoly I. Kalinovsky Sergey A. Avilov Pelageya V. Andrijaschenko Roman S. Popov Pavel S. Dmitrenok Ekaterina A. Chingizova Vladimir I. Kalinin 《Marine drugs》2020,18(11)
Six new monosulfated triterpene tetra-, penta- and hexaosides, namely, the kurilosides A1 (1), A2 (2), C1 (3), D (4), E (5) and F (6), as well as the known earlier kuriloside A (7), having unusual non-holostane aglycones without lactone, have been isolated from the sea cucumber Thyonidium (= Duasmodactyla) kurilensis (Levin) (Cucumariidae, Dendrochirotida), collected in the Sea of Okhotsk near Onekotan Island from a depth of 100 m. Structures of the glycosides were established by 2D NMR spectroscopy and HR-ESI mass spectrometry. Kurilosides of the groups A and E contain carbohydrate moieties with a rare architecture (a pentasaccharide branched by C(4) Xyl1), differing from each other in the second monosaccharide residue (quinovose or glucose, correspondingly); kurilosides of the group C are characterized by a unique tetrasaccharide branched by a C(4) Xyl1 sugar chain; and kurilosides of the groups D and F are hexaosides differing from each other in the presence of an O-methyl group in the fourth (terminal) sugar unit. All these glycosides contain a sulfate group at C-6 of the glucose residue attached to C-4 Xyl1 and the non-holostane aglycones have a 9(11) double bond and lack γ-lactone. The cytotoxic activities of compounds 1–7 against mouse neuroblastoma Neuro 2a, normal epithelial JB-6 cells and erythrocytes were studied. Kuriloside A1 (1) was the most active compound in the series, demonstrating strong cytotoxicity against the erythrocytes and JB-6 cells and a moderate effect against Neuro 2a cells. 相似文献
10.
温带海域普遍养殖仿刺参,仿刺参养殖塘中常有大型藻类爆发,进而影响仿刺参的生长和生存。通常用扑草净清除大型藻类,由于除草剂的生态毒性,可推断扑草净将影响仿刺参生物沉积物中营养盐的再生,本研究则要验证该假说。将仿刺参生物沉积物暴露于不同浓度的扑草净7天,并测定生物沉积物-水界面营养盐的扩散通量。结果表明:在正常使用的去除大型藻类的扑草净剂量之下,营养盐在仿刺参生物沉积物-水界面的扩散通量不受扑草净的影响。按正常剂量使用扑草净并不影响仿刺参生物沉积物中营养盐的再生与积聚,无需对扑草净对营养盐水平的影响而担忧。研究结果将有助于评估除草剂对海水中营养盐循环的影响。 相似文献