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1.
东海带鱼年龄与生长的研究 总被引：8，自引：2，他引：6
本文利用2002年12月～2004年8月在东海中北部(27°～34°N、126°E以西)所获取的带鱼渔获样品,共采集788ind,每月对带鱼矢耳石生长轮计测和带鱼样品基础生物学测定,研究带鱼年龄与生长之间的关系。结果表明,目前东海群系带鱼呈现出较以往任何时期低龄化和生长加快的渔业生物学特征;体重与肛长的关系性别间无明显差异;该群系的生长其性别间无显著差异,雌雄合并估算的vonBertalanffy生长参数L∞=493.3mm,K=0.346/yr,t0=-0.387yr。 相似文献
2.
再议东黄渤海带鱼种群划分问题 总被引：1，自引：0，他引：1
本研究根据中国水产科学研究院东海水产研究所早年收集的1971—1982年带鱼(Trichiurus lepturus)捕捞统计资料,从地理隔离、数量动态方面分析我国近海带鱼种群的划分问题。研究结果表明,东黄渤海带鱼存在两个种群,即黄渤海种群和东海种群。通过带鱼鱼群移动影像发现,黄渤海带鱼和东海带鱼在江苏北部近海(34?00?N,121?00?E)附近发生了混栖,这一海域的带鱼产量仅占当月总产量的1.16%;两种群带鱼在外海越冬场也发生混栖,这一海域带鱼产量仅占当月总产量的5.51%。本研究认为,之所以分为黄渤海带鱼和东海两个种群,主要证据有6个:其一,可能发生混栖海域带鱼群体的数量很少,均仅占当月带鱼产量的极少数;其二,在混栖海域,不同带鱼鱼群并未发生群体间个体完全混合,在产卵洄游过程中,各自群体将仍旧依照各自洄游路线回到越冬场,因而在产卵场发生遗传杂交的可能性很少;其三,带鱼在越冬场的混合不属于产卵场杂交,因此,不同种群带鱼因为产卵和杂交发生种群遗传性状融合的可能性较少;其四,黄渤海带鱼和东海带鱼有着各自不同的数量变化规律,两者近年来产量差距悬殊,黄渤海种群带鱼资源在衰退的同时,没有得到东海带鱼群体的补充;其五,除了在江苏北部近海和外海发生群体混栖,黄渤海带鱼和东海带鱼各自的分布空间完全隔离;其六,这两个不同带鱼种群在洄游中存在不同的水团背景。结合以往带鱼种群体征差异分析的结果,可以认为,黄渤海带鱼和东海带鱼分属不同的带鱼种群。在东黄渤海,带鱼整体上可以划分为黄渤海带鱼种群和东海带鱼种群。 相似文献
3.
Masaya Toyokawa Akio Shimizu Katashi Sugimoto Kou Nishiuchi Toru Yasuda 《Fisheries Science》2010,76(1):55-62
To determine the reproductive season of the giant jellyfish Nemopilema nomurai, we investigated gonadal maturity in specimens collected from the East China Sea, Korea Strait, Wakasa Bay, and the Shonai Coast of Yamagata Prefecture. After the sex of the samples was determined, the long axis of at least 256 oocytes from each female was measured. In specimens collected from the coast of Japan in 2005 and in 2006, all gonads were sufficiently developed to determine sex. However, 18 of the 20 specimens from the East China Sea collected in July 2005 were immature, and sex could not be determined. The maximum and third quartile of oocyte length had a significant correlation with days elapsed from 30 June, but they were not related to bell diameter. Observations of gonad tissue sections of specimens collected in Wakasa Bay in 2006 confirmed that oocyte length was a good proxy for female maturity. Male maturity could also be determined. In conclusion, the sex of all of the small-sized medusae collected along the coast of Japan was determinable, and their gonads were at various stages of development up to fully mature. Therefore, the occurrence of small-sized jellyfish during the autumn in Wakasa Bay is not caused by recruitment of young population from the nearby coast. 相似文献
4.
秋季东海北部和黄海南部沙海蜇资源分布及其与底层温盐度的关系 总被引：1，自引：0，他引：1
根据2006～2009年秋季在东海北部和黄海南部对沙海蜇(Nemopilema nomurai)和温盐度的同步监测数据,对秋季沙海蜇的资源分布特点及其和底层温盐度的关系进行了研究。结果表明:秋季东海北部和黄海南部沙海蜇的高生物分布区主要集中在以下3个海域:(1)南黄海西侧浅水海域;(2)南黄海中央深水区(32°30'N～34°00'N、123°00'E～124°30'E);(3)大沙和长江口外海水域。前2个高生物量分布区某些年份会连成一片,第二个高生物量区基本上每年都会出现,第三个高生物量区某些年份可能不会出现。结合底层温盐度的分布特征,可以看出:沙海蜇高生物量区主要出现在黄海冷水团的前缘或冷暖水团的交汇处,且在冷暖水团的交汇处,更易形成高生物量聚集。而在暖水团控制的海域内,其生物量较低,在垂直分布上,沙海蜇可能主要活动区域在30 m以深的水温相对较低(低于15℃)且变化幅度较小、盐度处于中盐水平(32.0～33.5)的水体内。 相似文献
5.
Fanomezantsoa Randriarilala Toshihide Kitakado Daisuke Shiode Masayuki Sakaguchi Toshifumi Hayashi Tadashi Tokai 《Fisheries Science》2014,80(2):261-271
Information on the distribution and bloom scale of the giant jellyfish Nemopilema nomurai is necessary to understand the impact on fisheries. In October 2009, we had an opportunity for visual counting of N. nomurai around Japan from a research/training vessel. To take into account possibly severe missed detection of N. nomurai in the close vicinity of the vessel, detection functions were modified by introducing an additional parameter δ expressing the proportion of detectable N. nomurai within a threshold perpendicular distance. Some covariate effects in the detection process were also investigated. The δ-modified hazard-rate detection function with δ variation parameter of jellyfish body size was chosen as the best-fit one by AIC model selection. The results suggested that a higher proportion (>30 % or more) of N. nomurai were undetected in the vicinity of vessel. The δ-modified model had an advantage of no loss of left-truncated data and provided better estimation of density with the smaller coefficient of variation than the conventional left truncation approach. It is applicable to other line transect surveys, e.g. aerial surveys. High densities of N. nomurai were found in the central part of the Sea of Japan and off Iwate Prefecture. 相似文献
6.
本研究选取山东长岛、辽宁海洋岛和獐子岛底播的虾夷扇贝(Patinopecten yessoensis)群体、人工选育的“獐子岛红”品种养殖群体、辽宁旅顺自然群体以及原产地日本青森县陆奥湾自然群体,运用稳定同位素技术探究虾夷扇贝不同地理群体的特征.结果显示,(1)虾夷扇贝各群体的闭壳肌和内脏团δ13C值分别为-20.47‰±0.66‰和-24.13‰±2.41‰;闭壳肌和内脏团δ15N值分别为8.52‰±1.32‰和7.26‰±0.49‰.(2)基于δ13C值和δ15N值的单因素方差分析(One-wayANOVA)显示,群体间各个取样点闭壳肌和内脏团的碳、氮稳定同位素比值差异显著(P＜0.05);基于地理位置构建所有群体的碳氮稳定性同位素散点分布图,可以明显地区别中国群体和日本群体.(3)中国8个虾夷扇贝群体之间,只有长岛群体的碳、氮稳定同位素比值明显低于其他群体,而其余群体之间差异不显著(P＞0.05).研究表明,虾夷扇贝中国群体与日本群体间已经存在较大的差异,且中国群体间因生长海域、水文环境的不同也呈现出分群现象.说明虾夷扇贝定居群体在不同的生态环境下已产生了不同程度的适应性改变. 相似文献
7.
东海发光鲷生物量分布及其与环境的关系 总被引：1，自引：0，他引：1
根据2005年12月~2006年11月东海(27°00′~34°00′N、122°00′~127°00′E)底拖网资源调查资料,分析了东海发光鲷的生物量的分布特征以及与环境条件的关系。结果表明:春、秋季发光鲷主要分布在东海南部外海,生物量较高;夏季分布较广,以东海北部外海为主,生物量较低;冬季分布较为集中,以东海南部外海为主。夏季发光鲷的生物量与温度、盐度以及水深的关系的曲线拟合显示,夏、秋季发光鲷主要分布于24℃左右的水温,最适盐度在33左右,最适水深在75 m左右。 相似文献
8.
物种多样性空间分布是生态学研究的重要内容之一,空间插值法在该领域应用广泛。本研究以2017年5月黄海和东海北部游泳动物多样性为例,选取种类数(S)、Shannon-Weaver多样性指数(H′)、Pielou均匀度指数(J)和Margalef丰富度指数(d)来衡量该海域物种多样性,应用反距离加权法(Inverse distance weighted, IDW)、径向基函数法(Radial basis function, RBF)、局部多项式法(Local polynomial interpolation, LPI)、普通克里格法(Ordinary kriging, OK)和协同克里格法(Ordinary cokriging, COK)对上述4种多样性指数进行插值,通过jackknife检验的方法选择适合每种多样性指数的空间插值法。结果表明,对于4种多样性指数,COK结果均最好,而其他4种方法精度较低,且差别不大。COK预测结果表明,S和d都呈现出东南部高,北部次之,中部最低的格局。H′和J也是中部最低,在南部和北部海域差异不大。4种多样性指数在32?N以南海域的高值区范围大致相同。COK可以作为黄海和东海北部游泳动物多样性空间插值的方法。 相似文献
9.
东海区短鳄齿鱼数量分布及其与环境因子的关系 总被引：4，自引：3，他引：1
根据2005年东海区(26°30′～35°00′N、121°00′～127°00′E)渔业资源监测底拖网调查资料,结合广义相加模型(GAM)方法分析了东海区短鳄齿鱼资源的时空分布特征以及水深、水温、盐度与数量分布的关系。结果表明:东海区短鳄齿鱼主要分布区域为:28°00′～30°00′N、123°00′～126°30′E;生物量季节变化明显,以秋季(9月)最高,春季(4月)最低;短鳄齿鱼适宜水深、温度、盐度范围分别为70～110 m、17～23℃、34.3～35.2。结合东海海流分布特点,初步推断短鳄齿鱼为暖水性海洋小型鱼类,其生物量分布和季节变化受台湾暖流影响。 相似文献
10.
11.
本研究对南黄海西北部山东半岛沿岸的沉积柱140年的颗石藻(Coccolithophores)样品进行了种类组成和丰度分析。结果显示,共发现颗石藻8种,平均丰度为9.76×10~6个/g,丰度范围为(5.07～14.21)×10~6个/g。其中,大洋桥石藻(Gephyrocapsa oceanica)和赫氏艾密里藻(Emiliania huxleyi)是丰度较高的主要物种,平均丰度分别为4.96×10~6、4.55×10~6个/g。通过比较沉积记录与气候参数发现,颗石藻丰度的长期变化与东亚冬季风的替代指标海平面气压(SLP)有一定相关性,黄海沿岸流受季风影响,随着东亚冬季风的增强而加强,沿岸流带来了物质输入,为研究区域的颗石藻提供了丰富的营养盐,从而支撑了较高的颗石藻丰度。 相似文献
12.
The spawning grounds of the chub mackerel (Scomber japonicus) and spotted mackerel (Scomber australasicus) in the East China Sea were estimated based on catch statistics of the Japanese large- and medium-type purse seine fishery
from 1992 to 2006. Biometric data were obtained from specimens caught by purse seiners in the East China Sea from 1998 to
2006. Gonadosomatic index (GSI) at 50% sexual maturity of chub mackerel and spotted mackerel females was 2.5 and 2.6, respectively.
Using this criterion for GSI, chub mackerel larger than 275 mm and spotted mackerel larger than 310 mm in fork length were
considered to be mature. Mature chub mackerel was observed in the area of 15–22°C sea surface temperature (SST), and mature
spotted mackerel was observed in the area of 17–25°C SST. The spawning period of chub mackerel ranged from February to June,
and that of spotted mackerel ranged from February to May in the East China Sea. The spawning grounds were estimated from the
distributions of catch per unit effort (CPUE) of spawners and SST. As a result, the spawning ground of chub mackerel was estimated
to be in the central and southern part of the East China Sea and the area west of Kyushu in February, March, and April, and
in the central part of the East China Sea, the area west of Kyushu and Tsushima Straight in May, and in Tsushima Straight
and western part of the Sea of Japan in June. The spawning ground of spotted mackerel was estimated to be in the central and
southern part of the East China Sea and southern coastal area of Kyushu in February, March, and April, and the central and
southern part of the East China Sea and the area west of Kyushu in May. 相似文献
13.
为了摸清东、黄海日本鲭的资源量和渔业利用状况,以2007年5～12月在东海近海和黄海中南部海域渔获的日本鲭叉长的测定数据为基础材料,结合东、黄海区的渔业产量统计资料,应用体长结构实际种群分析法(VPA)估算了2007年东海西部日本鲭种群的资源量,并分析了该资源的结构和利用程度。结果表明,中国利用东海西部日本鲭种群的年龄结构以当年生幼鱼(31.87%)和1龄鱼(49.90%)为主,现存年平均资源尾数和资源量分别为3.68×109N和39.55×104t;该资源的利用程度处于中度偏低开发状态,最大持续产量(MSY)为24.08×104t,年渔获量已超过MSY,进一步开发利用的潜力不大;禁止利用当年生的幼鱼,能使资源处于更佳状态。通过分析该资源的渔业利用时间和年龄结构,认为年产量即使超过MSY,该资源群体仍能保持相对稳定的状态。 相似文献
14.
Genetic population structure of <Emphasis Type="Italic">Nibea albiflora</Emphasis> in Yellow Sea and East China Sea 总被引：1，自引：0，他引：1
Zhi Qiang Han Tian Xiang Gao Takashi Yanagimoto Yasunori Sakurai 《Fisheries Science》2008,74(3):544-552
ABSTRACT: The population genetic structure and level of gene flow of Nibea albiflora from the Yellow Sea and the East China Sea were examined with a 479-bp segment of a mtDNA control region. In total, 65 samples were collected from three locations and 37 haplotypes were obtained. Mean haplotype diversity and nucleotide diversity for the three populations ranged from 0.9130 ± 0.0308 (Zhoushan) to 0.9926 ± 0.0230 (Xiamen), and from 0.0073 ± 0.0043 (Qingdao) to 0.0099 ± 0.0057 (Xiamen). Analysis of molecular variance and pairwise F ST revealed little genetic structure between the Yellow Sea and the East China Sea in N. albiflora . But based on the exact test of differentiation, the null hypothesis that N. albiflora within the Yellow Sea and the East China Sea constitutes a panmictic mtDNA gene pool was rejected. This might be caused by the broad spawning areas but not by the Yangtze River outflow. Mismatch distribution revealed that N. albiflora has undergone population expansion, possibly before the last 85 000–170 000 years. The existence of high gene flow between stocks in the studied area was supported by our results. Annual migrations, larval drift in the ocean currents, and recent range expansion could be the reasons for little genetic structure in the studied area. 相似文献
15.
The swimming depths of 12 individual Nemopilema nomurai with bell diameters of 0.8–1.6 m were investigated using pop-up archival transmitting tags and ultrasonic pingers, and the
validity of the research method was evaluated. The N. nomurai studied frequently showed vertical movement, with the swimming depth ranging from 0 to 176 m, The mean swimming depths of
most individuals were less than 40 m. The swimming depths of N. nomurai in the northern Japan Sea in the winter were mostly deeper than those of this species in the southern Japan Sea in the autumn.
This result suggests that the range of the depths almost depends on the vertical structure of the ocean. Swimming depths during
the nighttime were significantly deeper than those during the daytime. More specifically, during the daytime, the swimming
depths in the afternoon tended to be shallower than those in the morning, while during the nighttime, the swimming depths
after midnight were deeper than those before midnight. 相似文献
16.
使用地统计二阶广义线性混合模型(geostatistical delta-GLMM)分析了2001—2011和2015—2017年黄、渤海小黄鱼越冬群体在黄海中部、南部的空间分布,并用geostatistical delta-GLMM、基于普通克里格插值法和基于站位调查设计的扫海面积法分别估计了小黄鱼资源量指数,对geostatistical delta-GLMM相较基于普通克里格插值法和基于站位调查设计的性能进行了比较研究。结果显示,在2001和2002年,黄海越冬场主要存在北部(36°00′～37°37.5′N,123°15′～124°15′E)、中部(33°75′～36°00′N,123°15′～124°75′E)和东南部(32°00′～33°75′N,124°00′～125°15′E)3个生物量高密度区,其中中部区密度最高。从2003年开始,小黄鱼的生物量密度开始下降,北部和东南部高密度区下降程度高于中部高密度区;至2016—2017年高密度区变得不明显。冬季小黄鱼总资源量指数与小黄鱼的年产量、渔船功率变化趋势相反,呈下降趋势,且大部分年份站位数在37站以上,站位范围覆盖了本实验区域,可排除采样站位因素,这说明小黄鱼资源仍面临过度捕捞,种群处于衰退状态。研究表明,地统计二阶广义线性混合模型估计的2001—2017年冬季黄海中部、南部小黄鱼的总资源量指数相对扫海面积法和普通克里格法的估计值精确度更高。 相似文献
17.
东海区七星底灯鱼数量分布以及与温盐度的关系 总被引：1，自引：2，他引：1
本文利用从2000年12月到2001年9月一个周年的渔业资源调查数据,对东海区七星底灯鱼的数量分布及其与温盐度的关系进行了研究。结果表明:东海区的七星底灯鱼可分为东海北部和浙江中南部近海2个群体。以东海北部群体较大,主要分布在30°N以北的海域;浙江中南部近海群体较小,且只有零星分布。七星底灯鱼在东海北部海域从沿岸到外海都有分布,但沿岸数量较少,主要分布在30°30′~32°30′N、124°00′~126°30′E之间的海域;以冬春季节分布面较广,夏秋季节的分布面较窄。东海北部群七星底灯鱼栖息海域的表层温度值变化较大,以春季最低,秋季最高;密集分布区的等温线变化范围在1~2℃左右。浙江中南部近海群的栖息水温变化较小,全年都在20℃以上。各季节浙江中南部近海群的适宜水温均高于东海北部群。各季节东海北部群密集分布区的表层盐度在32.0~34.5之间,以冬春季的盐度值较高,夏秋季的盐度值较低;浙江中南部近海群的栖息海域表层盐度除冬季较高外,其余季节相对较低。 相似文献
18.
东、黄渤海带鱼的洄游路线 总被引：3，自引：0，他引：3
为了研究带鱼的洄游路线,根据我国10余个主要渔业公司1971、1972、1981和1982年带鱼捕捞统计资料,先绘制带鱼鱼群移动影像图,据此进一步研究东、黄渤海近海带鱼的洄游路线图。结果显示,带鱼越冬场、产卵场和索饵场范围广阔,在空间上具有一定的重叠性。带鱼还有分批越冬、产卵和索饵洄游的特性,不同群体越冬、产卵和索饵洄游在时间上也有一定的重叠性。北方带鱼群体的越冬场主要在32°00'～36°00'N,124°00'～126°00'E黄海暖流水域。3—7月北上进入海州湾、乳山湾、海洋岛和渤海各湾产卵场;8—9月在产卵场外围宽阔水域索饵;9—11月游出渤海,绕过成山头南下,沿禁渔线外侧,沿途分别汇合海州湾、乳山湾及海洋岛的越冬鱼群,到了34°00'N后折向东南,分批于12月到达越冬场。南方带鱼群体越冬场主要位于浙江中南部禁渔线外侧,其次是济州岛西南海域。每年3—4月起,南部越冬的带鱼鱼群大致以每2个月1个纬度的速度向东北方向移动;5—7月,产卵洄游的鱼群到达舟山渔场和长江口渔场产卵;7—8月,产卵后的索饵群体北上黄海南部大沙渔场索饵;9月,索饵群体前锋到达35°00'N禁渔线外侧。10月以后,随着冷空气南下,南部群体带鱼向南越冬洄游,并且在10月回到长江口海域。其中小部分群体游向外海越冬场,大部分群体继续南下回到东海中南部近海的越冬场。台湾暖流和黄海暖流的进退和消长是影响带鱼越冬洄游路线空间和时间变化的主要环境因素。 相似文献
19.
2006年夏秋季东海群系澳洲鲐数量分布特征 总被引：5，自引：0，他引：5
利用2006年7~11月大型机轮灯光围网在东海外海的生产资料,并结合生物学测定数据以及水温遥感数据,对夏秋季东海群系澳洲鲐数量分布时空变化特征进行了研究,并探讨了它们与海洋环境条件的关系。结果表明:夏秋季东海外海海域的澳洲鲐主要为索饵群体,它们的高度集群期主要在7~9月份,其中以8月份较为明显;10月份以后,由于鱼群开始进行越冬洄游,移动速度明显加快,虽然有偶尔的高度集群现象,但是持续时间较短。在地理分布上,7~8月份,澳洲鲐索饵群体的主要分布在125°00′E以西、28°00′N以南海域;9月份,鱼群重心向东北方向转移,范围为125°00′~126°00′E、28°00′~28°30′N海域;10月份相对于9月份鱼群重心向东转移50 n mile,群体向北移动达150 n mile左右;11月份以后,澳洲鲐群体向东北方向的对马海峡转移且可能至日本海越冬。群体结构分析表明,夏秋季澳洲鲐的个体逐月迅速增大,且增长量以7~8月份较大,以后逐渐下降。根据澳洲鲐的群体移动规律以及海洋环境条件的变化,认为东海群系澳洲鲐属于黑潮边缘种,其中心渔场的变动和黑潮的强弱具有密切的关系。 相似文献
20.
Stefan Skori? Bo?idar Ra?kovi? Vesna Poleksi? Zoran Ga?i? Mirjana Lenhardt 《Aquaculture International》2012,20(3):525-535
Cormorants cause damage to fish in aquaculture not only by consuming large number of fish but also by wounding them. Quantification of the actual damage in fish induced by wounding is important for reliable estimations of the overall loss in aquaculture caused by cormorants. In this study, specimens of mirror and scaly carp (Cyprinus carpio L.) injured by attacks of great cormorant (Phalacrocorax carbo L.) were collected from the ??E?ka?? fish farm in Serbia. Surfaces of superficial and open subepithelial wounds (expressed as a percent of the total body surface), estimated by computer-assisted image analysis, had mean values 10.66?±?1.86 and 0.85?±?0.90, respectively. Histological evaluation of wounds was performed by two scoring systems: system proposed by Bernet et al. (J Fish Dis 22:25?C34, 1999) and modified system described by Wahli et al. (Aquaculture 225:371?C386, 2003). The most frequent histopathological changes were disturbed epidermal structure and surface cell morphology and increased number of club cells (on more than 75% of specimens); increased number of melanocytes and their distribution in different layers in dermis; and enlarged hypodermis (more than 80% of samples) and myolysis (50% of samples). Comparison of wounds?? surfaces (surface of superficial injures) and histopathological changes, estimated by two scoring systems, revealed significant positive correlation. Bernet??s scoring system showed higher correlation coefficients, when compared with the modified Wahli??s scoring system. 相似文献