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1.
《中国海洋大学学报(自然科学版)》2016,(11)
使用套网法在海州湾海域进行了坛子网3种网目尺寸(30、35和40mm)的网囊网目选择性试验。在分析渔获物组成的基础上,基于Logistic选择模型和数量生物量曲线(Abundance-biomass comparison curves,ABC曲线)法,获得了渔获物中主要经济品种小黄鱼(Pseudosciaena polyactis)、鹰爪虾(Trachypenaeus curvirostris)和口虾蛄(Oratosquilla oratoria de Haan)的选择性曲线和ABC曲线。结果表明,坛子网网囊网目尺寸为30、35和40mm时,小黄鱼的50%选择体长(L50)分别为7.920、9.503和11.229cm,选择范围(SR)分别为1.975、2.306和3.775cm;鹰爪虾的(L50)值分别为5.400、5.901和7.404cm,其SR值分别为1.283、1.376和1.709cm;口虾蛄的L50值分别为7.844、8.324和9.602cm,其SR值分别为2.680、2.719和2.973cm;随着网目尺寸逐渐增大,小黄鱼、鹰爪虾和口虾蛄选择性指标50%选择体长(L50)和选择范围SR值也随之逐渐增大。3种坛子网试验网囊内ABC曲线W值均小于0,表明针对海州湾目前整体生物群落,网囊网目尺寸需要进一步放大。本研究结果可为中国黄海区渔业资源可持续发展及张网网囊最小网目尺寸的确定提供科学参考。 相似文献
2.
为了评价和改善坛子网的作业性能,本文在网囊前端安装由方形网目网片(网目尺寸分别为35、40、45和50mm)和刚性框架(长80cm,宽60cm)所组成的方形网目逃逸窗装置来释放幼鱼,并利用套网法在海州湾海域开展海上试验。在分析渔获的基础上,运用相对重要性指数、logistic模型等分析方法,获得了坛子网渔获物种类组成、优势种和主要经济渔获物小黄鱼(Larimichthys polyactis)和鹰爪虾(Trachypenaeus curvirostris)的选择性曲线。研究显示,随着逃逸窗网目尺寸增大,小黄鱼、鹰爪虾的50%选择体长(L50)逐渐增大,且L50的值与逃逸窗网目尺寸呈线性关系;逃逸窗网目尺寸为35、40、45和50mm时,小黄鱼的L50分别为9.27、12.54、13.46和15.94cm,鹰爪虾的L50分别为5.31、6.35、7.73和8.66cm。根据试验结果,结合小黄鱼的最小可捕体长及鹰爪虾第一次性成熟体长,推算小黄鱼和鹰爪虾坛子网方形网目逃逸窗网目尺寸分别为47.7和36.3mm。研究结果可为我国海州湾海区渔具管理以及渔业资源的可持续发展与管理提供技术依据。 相似文献
3.
为了分析黄海区虾拖网网囊网目对副渔获物的选择性,运用套网法对30,33,40 mm 3种网目尺寸的网囊进行了选择性试验。用统计学方法求得几种优势副渔物的逃逸率,并用极大似然法对渔获数据进行处理求得相关的选择性参数。结果表明,大部分副渔获物的逃逸率随着网囊网目尺寸的增大而增大,在网目尺寸为30,33,40 mm时矛尾虎鱼(Chaeturichthys stigmatias)的逃逸率分别为48.3%,59.7%和62.6%;细巧仿对虾(Parapenaeopsis tenella)的逃逸率分别为67.0%,68.2%,68.7%。矛尾虎鱼的选择性参数也随着网目尺寸的增大而增大,在网目尺寸为30,33,40 mm时,矛尾虎鱼的50%选择体长L50分别为81.858,86.715和88.028 mm,选择范围SR分别为41.097,45.007和50.423 mm。研究表明,单靠放大网囊网目尺寸来释放虾拖网中副渔获物,效果不甚理想。 相似文献
4.
为支撑《全国海洋捕捞准用渔具目录》的实施与管理,本文利用套网法在黄海区海州湾海域开展了黄海双船变水层疏目拖网网囊选择性研究。在分析渔获的基础上,运用相对重要性指数(IRI)、Logistic模型等分析方法,获得了双船变水层疏目拖网渔获物种类组成、优势种和主要渔获物竹荚鱼(Trachurus japonicus)、小黄鱼(Larimichthys polyactis)和带鱼(Trichiurus lepturus)的选择性曲线。研究显示,随着网囊网目尺寸的增加,渔获物质量和逃逸率均逐渐增加;竹荚鱼、小黄鱼和带鱼的50%选择体长(L_(0.5))逐渐增大,且L_(0.5)与网囊网目尺寸呈线性关系;双船变水层疏目拖网网囊最小网目尺寸按照底拖网54 mm网目尺寸标准执行偏小。根据试验结果,结合小黄鱼、竹荚鱼和带鱼最小可捕规格,变水层疏目拖网网囊最佳网目尺寸分别为65.78、78.82和67.36 mm。在目前渔业资源状况下,为保护小黄鱼等中小型经济鱼类,建议将双船变水层疏目拖网网囊最小网目尺寸(网目内径)设定为66 mm。研究结果可为我国近海捕捞渔具管理以及渔业资源的可持续发展提供理论支撑。 相似文献
5.
为探索东海区日本方头鱼(Branchiostegus japonicus)三重刺网与海洋渔业资源的适宜性。2015年4月开展了3种型刺网(单片刺网、双重刺网和三重刺网)3种网目尺寸(50、60和70mm)的选择性试验。应用Normal、Lognormal、Gamma和Bi-normal 4种选择性曲线进行拟合,采用极大似然法估算模型参数研究3种型刺网的选择性。研究表明:3种型刺网共捕获种类33种,鲈形目最多(15种),鲉形目次之(5种),其中日本方头鱼为第一优势种,渔具具有较强的选择性;在同型刺网中,随着网目尺寸的增加(50~70mm),日本方头鱼优势体长组逐渐增大,网目尺寸对于其体长选择具有显著影响;日本方头鱼刺网最适选择性曲线为Lognormal曲线,3种型刺网选择性曲线基本相同;采用选择性曲线法推算出3种型刺网对日本方头鱼最佳网目尺寸依次为77.57、74.84和70.91mm。依据以上研究结果,针对日本方头鱼三重刺网,将其网目尺寸调整为70.91mm,可以有效保护当前渔业资源。 相似文献
6.
为研究虾拖网网囊网目对主要渔获种类的选择性,于2017年9月在南海区采用裤式拖网法进行选择性试验。在SELECT模型框架下,使用极似然估算法,结合单网次和联合网次的数据,同时考虑网次间差异,估算网囊对主要渔获种类的平均选择性。共完成14网次作业,其中对照网囊之间的渔获性能比较试验4次,试验网囊的选择性试验10次。研究表明:对照网囊的位置对其渔获性能无显著影响;试验网囊对刀额新对虾(Metapenaeus ensis)的网次50%选择体长(L 50)为78.84~92.09 mm,平均为82.38 mm,网次选择范围(SR)为5.01~11.32 mm,平均为6.39 mm,网次相对作业强度(p)为0.44~0.71,平均为0.52;试验网囊对黄斑蓝子鱼(Siganus oramin)的网次L 50为59.20~76.80 mm,平均为71.17 mm,网次SR为5.30~16.87 mm,平均为14.20 mm,网次p为0.43~0.71,平均为0.63。试验网囊对刀额新对虾的网次和平均L 50值均大于其首次性成熟体长(80 mm),可见试验网囊对刀额新对虾的资源利用是合理的。本试验的裤式拖网法和数据处理方法可为今后拖网选择性研究提供参考。 相似文献
7.
南海区虾拖网方目与菱目混合网囊渔获性能初步研究 总被引：1，自引：0，他引：1
虾拖网是南海区常见的作业方式,由于其网囊网目选择性差,虾拖网作业常产生大量的副渔获物。为了优化虾拖网网囊结构,提高其选择性,2015年8月在南海北部渔场用方形网目与菱形网目混合网囊进行试验。结果表明:虾拖网的渔获种类有34种;渔获种类中,康氏小公鱼(Anchoviella commersoni)、黑尾吻鳗(Rhynchoconger ectenurus)、中线天竺鲷(Apogon kiensis)和杂食豆齿鳗(Pisoodonophis boro)的尾数逃逸率均超过80%;周氏新对虾(Metapenaeus joyneri)和刀额新对虾(Metapenaeus affinis的尾数逃逸率最低,仅为6.18%和2.07%;周氏新对虾和刀额新对虾的50%选择体长(L50)分别为50.79 mm和53.858 mm;脊突猛虾姑(Harpiosquilla raphidea)的L50为62.51 mm;丽叶鲹(Caranx kalla)、中华青鳞鱼(Harengula nymphaea)、中线天竺鲷(Apogon kiensis)、赤鼻棱鳀(Thrissa kammalensis)和黄斑蓝子鱼(Siganus oramin)的L50分别为53.77、78.87、47.17、60.92和60.55 mm;混合网囊对鱼类副渔获的释放率较高,但对幼虾的释放率较低。建议今后放大网囊菱目段的网目尺寸进行相应的试验,提高混合网囊对目标种类的L50值,使其在释放鱼类副渔获物的同时释放幼虾,达到渔业资源的合理利用。 相似文献
8.
《中国海洋大学学报(自然科学版)》2016,(8)
本文根据2014年秋季青岛斋堂岛海域双桩竖杆张网的网囊网目选择性试验数据,运用PRIMER软件中的相似性分析、非参数多维标度分析和相似性百分比分析模块分析了张网渔具种类选择性。试验采用平行作业法,以传统网具(2a=16mm的菱形目网囊)作为对照网,设计了网目尺寸(2a)为30和35mm的菱形目网囊(以30D和35D表示)和网目尺寸(2a)为20、30和35mm的方形目网囊(以20S、30S和35S表示),进行选择性实验。研究显示:(1)35D、30S和35S渔获组成与对照网存在显著性差异,其余各网之间差异不显著。(2)改良后的试验网具能有效释放舒氏海龙;除20S组外,其余各试验网对方氏云鳚亦有较好的释放效果。(3)方形目网囊较相同尺寸的菱形目网囊具有更好的种类选择性;对相同网目形状的试验网囊进行比较,种类选择性随网目尺寸的增大而增大。(4)综合分析不同网具的渔获物组成和规格,在斋堂岛海域秋季小黄鱼、带鱼渔汛期,推荐使用30mm方形目网囊;方氏云鳚渔汛期,推荐使用20mm方形目网囊进行捕捞作业。研究结果表明,运用多元统计软件PRIMER进行张网渔具种类选择性分析虽然存在待完善之处,但该方法为本领域研究提供了有益参考。 相似文献
9.
海州湾近岸张网渔获物种类组成和资源利用现状分析 总被引：4，自引：0，他引：4
根据2011年3月~2012年12月海州湾沿岸定置张网调查资料,对海州湾张网渔获物组成进行比较分析。结果表明,张网渔获物组成具有明显的季节变化特征,春季以尖海龙(Syngnathus acus)、六丝钝尾虾虎鱼(Amblychaeturichthys hexanema)、双斑蟳(Charybdis bimaculata)、长蛸(Octopus variabilis)、方氏云鳚(Enedrias fangi)和口虾蛄(Oratosquilla oratoria)为主,秋季主要为小黄鱼(Larimichthys polyactis)、六丝钝尾虾虎鱼、三疣梭子蟹(Portunus trituberculatus)、日本枪乌贼(Loligo japonica)、鹰爪虾(Trachypenaeus curvirostris),冬季主要为六丝钝尾虾虎鱼、口虾蛄、鲜明鼓虾(Alpheus heterocarpus)、细鳌虾(Leptochela gracilis)和日本鼓虾(Alpheus Japonicus)。主要经济鱼类小黄鱼在9、10月产量最高,但达到可捕体长的小黄鱼不足1%,主要经济虾类鹰爪虾在9、10月产量最高,取样中69.46%的鹰爪虾达到可捕体长。渔捞日志记录表明,9月份单船平均网产达到最大值(17.01kg/net),12月份单船平均网产最低(2.87kg/net)。建议对张网渔业加强管理,开展生态型渔具渔法的研究,放大网目尺寸,加强对近海资源的养护。 相似文献
10.
为了研究桁杆虾拖网40 mm方目分离网片对渔获物的分隔效果和选择性,作者采用"套网法"于2015年8月在南海北部近海渔场进行了试验。计算分离网片对主要渔获物的尾数分隔率和质量分隔率,使用Logistic曲线作为选择性模型,运用极大似然估算法估算选择性参数。结果表明:虾拖网的目标种类为刀额新对虾(Metapenaeus ensis)和周氏新对虾(Metapenaeus joyneri),优势副渔获为丽叶鲹(Caranx(Atule)kalla);刀额新对虾和周氏新对虾的尾数分隔率和质量分隔率均大于90%;尾数分隔率和质量分隔率均大于80%的种类有:杂食豆齿鳗(Pisoodonophis boro)、黄斑蓝子鱼(Siganus oramin)、高体若鲹(Carangoides equula)和卵鳎(Solea ovata Richardson);丽叶鲹和脊突猛虾姑(Harpiosquilla raphidea)的尾数分隔率和质量分隔率均大于60%;周氏新对虾、脊突猛虾姑、丽叶鲹和黄斑蓝子鱼对分离网片的接触率分别为0.51、0.69、0.41和0.39,其50%选择体长(L50)分别为57.96±2.07、69.62±2.13、68.19±0.49和73.12 mm±1.26 mm。研究结果可为提高南海桁杆虾拖网的选择性积累数据,为缓解其对渔业资源补充群体的不良影响提供参考。 相似文献
11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ～200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ～380 km from the coast at a depth of ～250 m above the sea level. 相似文献
12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances
using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium
partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and
in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority
accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative
abundances of organic and inorganic carbon as an index of the carbon cycle stability. 相似文献
13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the
Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of
rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the
transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic
regime of the sea.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
14.
V. A. Ivanov S. P. Lyubartseva N. Mikhailova N. B. Shapiro 《Physical Oceanography》2001,11(6):509-524
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an
ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics
is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of
a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic
elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as
a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water
area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the
shelf zone and open sea.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
15.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area. 相似文献
16.
Relationship between the path of the Kuroshio in the south of Japan and the path of the Kuroshio Extension in the east 总被引：2，自引：0，他引：2
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry
dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly
goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with
the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then
passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state. 相似文献
17.
I. E. Timchenko A. A. Primalenny V. D. Yarin E. F. Vasechkina E. M. Igumnova 《Physical Oceanography》2001,11(4):367-378
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of
the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption
(fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by
the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with
application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem,
which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge,
water exchange with the Black Sea, etc.).
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
18.
I. G. Ostrovskaya 《Physical Oceanography》1992,3(5):397-403
Three mathematical models are considered: a two-dimensional model for calculating the concentration fields of the ecosystem components on the shelf of the Republic of Guinea, a pointwise model for the annual variation of the components, and a two predators-prey model. These models are used to study the effect of hydrodynamic conditions on the state of the shelf ecosystem and for research into the causes which distort the balance between marketable and unmarketable fish.Translated by Mikhail M. Trufanov. 相似文献
19.
Al. A. Shreider 《Oceanology》2007,47(1):91-103
The first data on the temporal evolution of the slope of the buried depression of the Black Sea are obtained. The sharp change in the rate of the decrease in the slope steepness that occurred in the Late Miocene-Pliocene time reflects a reorientation of the vector of mutual movement and a related intensification of the collision between the Arabian and Eurasian lithospheric plates. 相似文献
20.
The study of the sedimentary body of the Bransfield Strait has made it possible to identify several sedimentary complexes, to construct the first electronic charts for the acoustic basement, and to establish four stages of the evolution of its floor, which updates the previous knowledge about the formation of the strait. At the first stage, there was an increase in tension stresses that were accompanied by the local splits of the continental crust at the periphery of the Antarctic Peninsula. At the second stage, a graben-like structure filled with the Lower stratigraphic complex was formed northward of the Antarctic Peninsula. At the third stage, the continuing processes of extension led to intensive explosive activity of the growing volcanic structures and filling of the graben with sediments of the Middle seismostratigraphic complex. The fourth stage, which has continued until recently, is characterized by quasi-linear localization of the major centers of volcanic activity in the band closer to the South-Shetland Islands and the formation of the Upper seismostratigraphic sedimentary complex. The evolution of the floor of the Bransfield Strait reflects the process of penetration of the American-Antarctic ridge to the continental lithosphere of the Antarctic Peninsula for the last million years. 相似文献