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1.
茎柔鱼(Dosidicus gigas)是我国远洋渔业的重要捕捞对象。当前针对茎柔鱼渔场分布及其与环境关系的研究多集中于秘鲁海域,针对赤道海域茎柔鱼特定种群小型群体资源分布及其渔场环境特征研究较少。根据2019年12月至2020年2月茎柔鱼生物学数据,2019年12月至2020年4月生产和环境数据,运用胴长-体重关系拟合、地统计插值、广义可加模型(GAM)探究其资源分布及渔场环境状况。结果表明：东太平洋赤道海域茎柔鱼胴长范围为136~407 mm,体重范围为117~1557 g；2019年12月至2020年4月各月渔获量呈先增加后减小趋势,2月渔获量最高；CPUE曲线除2月增加外,总体呈下降趋势；渔场集中分布于0°~3°S、105°W~114°W海域,不同月份渔场重心经向变化明显；渔场最适SST范围是24.5~25.5 °C,最适Chl-a范围是0.16~0.20 mg/m3,月份是影响茎柔鱼CPUE的主要因子。研究表明：该海域茎柔鱼渔获主要为小型群体；小型群体生长发育期(2–3月)对渔场分布有重要影响,生长发育期前茎柔鱼集群度高,生长发育期后逐渐分散活动；单一影响因子与茎柔鱼CPUE相关性不显著,综合考虑其他环境因素及其交互影响是今后的研究方向。 相似文献
2.
本文利用1998-2016年西北太平洋柔鱼渔业数据及其渔场（35°~45°N，140°~165°E）的海洋遥感环境数据，包括海表温度、海面高度异常和叶绿素浓度，采用基于渔场环境的方法标准化西北太平洋柔鱼单位捕捞努力量渔获量（catch per unit effort，CPUE）。结果表明:柔鱼高频次作业的海表温度范围为10.2~22.2℃（96.05%），海面高度异常范围为-15.9~28.2 cm（97.91%），叶绿素浓度范围为0.0~1.0 mg/m3（96.69%）。名义CPUE和基于环境因子的标准化CPUE年际变化趋势基本一致。但由于柔鱼作业方式高度集中，有效捕捞努力量远低于名义捕捞努力量，以及考虑环境因子影响效应，名义CPUE均低于标准化CPUE。在深入理解鱿钓渔业和其生物学特性的基础上，基于渔场环境因子准化后的CPUE更具代表性，建议在以后的柔鱼资源评估与管理中使用基于渔场环境因子的标准化CPUE。 相似文献
3.
茎柔鱼(Dosidicus gigas)是我国远洋渔业的重要捕捞对象。当前针对茎柔鱼渔场分布及其与环境关系的研究多集中于秘鲁海域,而在赤道海域则研究较少。根据2019年12月至2020年2月在赤道海域获取的茎柔鱼生物学数据,以及同期的渔业生产和环境数据,运用胴长-体重关系拟合、Arcgis地统计插值、广义可加模型(GAM)探究其资源分布及渔场环境状况。结果表明:东太平洋赤道海域茎柔鱼胴长范围为136~407 mm,体重范围为117~1 557 g; 2019年12月~2020年4月各月渔获量呈先增加后减小趋势, 2月渔获量最高; CPUE (单位捕捞努力量渔获量)除2月增加外,总体呈下降趋势;渔场集中分布于0°~3°S、105°~114°W海域,不同月份渔场中心经向变化明显;渔场最适SST范围是24.5~25.5 ℃,最适chl a范围是0.16~0.20 mg/m3,月份是影响茎柔鱼CPUE的主要因子。进一步分析表明:该海域茎柔鱼渔获主要为小型群体;小型群体生长发育期(2~3月)对渔场分布有重要影响,生长发育期前茎柔鱼集群度高,生长发育期后逐渐分散活动;单一影响因子与茎柔鱼CPUE相关性不显著,综合考虑其他环境因素及其交互影响是今后的研究方向。 相似文献
4.
西北太平洋黑潮路径变化与柔鱼CPUE的关系研究 总被引：7，自引：0，他引：7
利用西北太平洋长时间序列SST、黑潮路径、柔鱼渔获量数据,基于GIS技术分析了黑潮路径类型变化和离岸摆动及其对柔鱼CPUE的影响。分析结果表明,1990—2003年,黑潮弯曲发生的月份数占82％,其中整月发生弯曲的月份数占47％,共发生2次大弯曲、2次准弯曲、5次小弯曲。柔鱼年CPUE,在黑潮发生准弯曲年份最高,黑潮发生小弯曲年份较高,黑潮发生大弯曲年份和平直年份较低,黑潮大弯曲发生的强盛年份最低。柔鱼月CPUE高值时段,多是黑潮发生弯曲时段,且主要是C型弯曲。连续3月以上出现月CPUE高值段,黑潮路径模式是C型弯曲和平直路径交替出现。3天CPUE的高值时段,黑潮弯曲型的频次远高于平直型;较高值时段,黑潮弯曲型的频次稍高于平直型;中值时段,黑潮平直型频次稍高于弯曲型;较低值时段,黑潮平直型高于弯曲型;低值时段,黑潮平直型远高于弯曲型。 相似文献
5.
光合有效辐射(PAR)对于海洋初级生产力具有显著的调控作用，会间接影响到头足类的资源丰度和渔场分布。本文根据2006?2015年上海海洋大学鱿钓科学技术组提供的柔鱼鱿钓数据和光合有效辐射卫星遥感数据，研究了光合有效辐射与西北太平洋柔鱼种群的关系，并评估了异常环境条件下光合有效辐射对柔鱼的影响。结果发现，柔鱼单位捕捞努力量渔获量(CPUE)、渔场纬度重心、PAR，及其空间分布均具有显著的月间变化。7?11月各月适宜PAR范围分别为36～39 E/(m2·d)、33～36 E/(m2·d)、24～27 E/(m2·d)、18 E/(m2·d)和12 E/(m2·d)，最适宜PAR值分别为36 E/(m2·d)、33 E/(m2·d)、27 E/(m2·d)、18 E/(m2·d)和12 E/(m2·d)。此外，CPUE与PAR有显著正相关关系(p<0.05)，且CPUE与各月适宜PAR范围占渔场比例也呈显著正相关(p<0.05)；同时渔场纬度重心随各月最适PAR平均纬度变化而变化。在异常环境条件下，拉尼娜年份CPUE值比厄尔尼诺年份高，该年份PAR值异常增高可能是导致柔鱼资源丰度增加的因素之一。研究表明，光合有效辐射对于西北太平洋柔鱼资源丰度和空间分布具有显著影响。 相似文献
6.
东南太平洋秘鲁海域光合有效辐射对茎柔鱼资源丰度和空间分布的影响研究 总被引：4，自引：2，他引：2
光合有效辐射（PAR）是海洋初级生产力的重要驱动因素之一,因此对海洋鱼类的资源丰度和空间分布产生潜在影响。本文根据2006-2015年1-12月中国鱿钓科学技术组提供的秘鲁外海茎柔鱼捕捞数据和光合有效辐射卫星遥感数据,以单位捕捞努力量渔获量（CPUE）表征资源丰度,以CPUE的纬度重心表征渔场空间分布,评估了东南太平洋秘鲁海域光合有效辐射对茎柔鱼资源变动的影响。结果发现,茎柔鱼渔场的产量、捕捞努力量、CPUE和PAR呈现明显的月间变化,其中CPUE和PAR月间变化规律表现为1-6月降低,7-12月增加的趋势。相关分析法表明,CPUE与PAR呈正相关关系,7月和8月相关性显著,而其余月份相关性不显著。依据频率分布法估算了各月适宜和最适PAR范围,各月最适PAR范围占渔场总面积比例与CPUE呈显著正相关关系,推测茎柔鱼资源丰度可能由各月适宜PAR面积大小决定;同时,最适PAR纬度与CPUE纬度重心呈显著正相关,说明茎柔鱼渔场的空间分布受最适PAR纬度的显著影响。此外,拉尼娜年份茎柔鱼适宜PAR面积要显著高于厄尔尼诺年份。研究表明,茎柔鱼资源丰度和空间分布受光合有效辐射的显著影响,其调控作用在不同气候条件下呈现不同的变化规律。 相似文献
7.
茎柔鱼主要分布于东太平洋，是我国鱿钓渔船的主要捕捞对象，气候变化对其栖息地有较大影响。本研究依据1950?2015年海表温度(SST)、海表高度距平(SSHA)以及尼诺指数(Ni?o3.4指数)，计算秘鲁外海茎柔鱼栖息地适宜性指数(HSI)，分析在厄尔尼诺(El Ni?o)、正常气候和拉尼娜(La Ni?a)条件下适宜栖息地的时空变动。分析表明，海表温度距平(SSTA)和SSHA与Ni?o3.4指数的变化趋势基本相同，Ni?o3.4指数与SSTA和SSHA均呈显著正相关，但与HSI值呈显著负相关。依据气候事件的定义，将研究年份划分为El Ni?o年，正常年和La Ni?a年。研究发现，在El Ni?o年，茎柔鱼渔场水温变暖，海面高度上升，适宜的SST和SSHA范围缩小，导致适宜的栖息地面积范围缩减；而在正常气候和La Ni?a年份，茎柔鱼渔场水温变冷，海面高度下降，适宜的SST和SSHA范围增大，因此适宜的栖息地面积范围增加。此外，Ni?o3.4指数和茎柔鱼渔场HSI纬度重心呈显著正相关，在El Ni?o事件下适宜的栖息地纬度重心向南偏移。研究认为，不同ENSO事件下茎柔鱼渔场环境变化显著，进而影响茎柔鱼适宜的栖息地范围及其空间分布。 相似文献
8.
基于朴素贝叶斯的西北太平洋柔鱼渔场预报模型的建立 总被引：2，自引：0，他引：2
西北太平洋是中国进行柔鱼(Ommastrephes bartramii)捕捞生产的重要海区,准确预报渔场出现的位置对提高渔业捕捞产量、节省燃油有重要的意义。本研究利用2002—2011年中国在该海域的历史产量数据、渔场时空数据以及包括海表温度、叶绿素浓度a、表温梯度强度和叶绿素梯度强度在内的海洋环境数据,基于朴素贝叶斯方法,建立了西北太平洋柔鱼渔场的预报模型。为满足朴素贝叶斯方法对条件独立性的假设,利用独立成份分析,重新获得相互独立的属性变量。通过求Cohen′s Kappa系数最大值的方法,确定3种CPUE类型的先验概率,建立可用于渔场预报的朴素贝叶斯预报模型。作为实际验证,将2012年7~11月我国柔鱼渔船在西北太平洋实际生产数据与预报的高CPUE渔场位置进行叠加,平均综合预报精度达到69.9%,表明该模型对西北太平洋渔场的预报具有较好效果和可行性。 相似文献
9.
秘鲁外海茎柔鱼栖息地适宜性年代际变动 总被引：1，自引：0，他引：1
茎柔鱼广泛分布于东南太平洋海域，是我国重要的远洋捕捞对象之一，其种群易受气候和栖息地环境的影响。利用海表面温度(SST)和海表面高度距平(SSHA)两个关键环境因子，计算1950?2015年1?12月秘鲁外海茎柔鱼栖息地适宜性指数(HSI)，对比分析太平洋年代际涛动(PDO)位于冷暖位相下茎柔鱼渔场环境以及栖息地质量的变动。结果显示，1950?2015年PDO呈现冷、暖、冷3个位相变化，其中PDO冷位相内的SST距平(SSTA)和SSHA明显低于PDO暖位相。交相关分析结果表明，PDO指数与SSTA和SSHA均呈显著正相关，而HSI与PDO指数、SSTA和SSHA均呈显著负相关。PDO位于冷位相时，茎柔鱼渔场内水温变冷，海面高度下降，适宜的SST和SSHA范围增加，因此茎柔鱼有利的栖息地面积增大；而PDO位于暖位相时，水温增暖，海面高度上升，适宜的SST和SSHA范围缩减，导致茎柔鱼适宜的栖息地面积缩小。研究认为，太平洋年代际涛动调控了茎柔鱼渔场内的环境变化，进而对茎柔鱼栖息地质量及适宜栖息地范围产生显著影响。 相似文献
10.
秘鲁外海茎柔鱼渔场分布与表温及表温距平值关系的初步探讨 总被引：4，自引：0，他引：4
根据2006年6~11月我国远洋船队秘鲁茎柔鱼生产统计及其表温(SST)、表温距平值(SSTA)数据,利用GIS软件ArcGIS9.0,对各月平均日产量(CPUE)和SST、SSTA关系的分布图进行绘制并分析,计算作业渔场重心。结果表明,6~8月的产量和CPUE比其他月份高。6~11月作业渔场在80°W~85°W,10°S~15°S,渔场重心在81°W~84°W,11°S~14°S。产量主要集中在12°~14°S海域,约占年总产量的72.72%,与2004-2005年有较大差异。6月作业渔场的SST为21~23℃,7、8月分别为19~21℃和18~20℃,9~11月为18~21℃。6月作业渔场的SSTA为0.1~0.2℃,7、8月分别为0.5~0.7℃,9~11月分别为0.2~0.6℃、1.0~1.4℃和0.4~0.7℃。研究认为,茎柔鱼渔场分布与SST、SSTA关系密切,可作为寻找中心渔场的海洋环境指标。 相似文献
11.
In order to examine the formation, distribution and transport of North Pacific Intermediate Water (NPIW), repeated hydrographic
observations along several lines in the western North Pacific were carried out in the period from 1996 to 2001. NPIW formation
can be described as follows: (1) Oyashio water extends south of the Subarctic Boundary and meets Kuroshio water in intermediate
layers; (2) active mixing between Oyashio and Kuroshio waters occurs in intermediate layers; (3) the mixing of Oyashio and
Kuroshio waters and salinity minimum formation around the potential density of 26.8σθ proceed to the east. It is found that Kuroshio water flows eastward even in the region north of 40°N across the 165°E line,
showing that Kuroshio water extends north of the Subarctic Boundary. Volume transports of Oyashio and Kuroshio components
(relative to 2000 dbar) integrated in the potential density range of 26.6–27.4σθ along the Kuroshio Extension across 152°E–165°E
are estimated to be 7–8 Sv (106 m3s−1) and 9–10 Sv, respectively, which is consistent with recent work.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
Konstantin V. Lebedev Max Yaremchuk Humio Mitsudera Iwao Nakano Gang Yuan 《Journal of Oceanography》2003,59(6):751-763
A finite-difference quasigeostrophic (QG) model of an open ocean region has been employed to produce a dynamically constrained
synthesis of acoustic tomography and satellite altimetry data with in situ observations. The assimilation algorithm is based upon the 4D variational data interpolation scheme controlled by the model's
initial and boundary conditions. The data sets analyzed include direct and differential travel times measured at the array
of five acoustic transceivers deployed by JAMSTEC in the region of the Kuroshio Extension in 1997, Topex/Poseidon altimetry,
CTD soundings, and ADCP velocity profiles. The region monitored is located within the area 27.5°–36.5°N, 143°–155°. The results
of assimilation show that mesoscale variability can be effectively reconstructed by five transceivers measuring direct and
reciprocal travel times supported by relatively sparse in situ measurements. The misfits between model and data lie within the observational error bars for all the data types used in assimilation.
We have compared the results of assimilation with the statistical inversion of travel time data and analyzed energy balances
of the optimized model solution. Energy exchange between the depth-averaged and shear components of the observed currents
reveals a weak decay of the barotropic mode at the rate of 0.2 ± 0.7⋅10−5 cm2/s3 due to topographic interaction. Mean currents in the region are unstable with an estimate of the available potential energy
flux from the mean current to the eddies of 4.7 ± 2.3⋅10−5 cm2/s3. Kinetic energy transition has the same sign and is estimated as 2.8 ± 2.5⋅10−5 cm2/s3. Potential enstrophy is transferred to the mesoscale at a rate of 5.5 ± 2.7⋅10−18 s−3. These figures provide observational evidence of the properties of free geostrophic turbulence which were predicted by theory
and observed in numerical experiments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
Yugo Shimizu Takanori Iwao Ichiro Yasuda Shin-Ichi Ito Tomowo Watanabe Kazuyuki Uehara Nobuyuki Shikama Toshiya Nakano 《Journal of Oceanography》2004,60(2):453-462
Six newly developed floats, which were set to drift on the 26.7 σθ isopycnal surface and to profile temperature, salinity and pressure above 1000 dbar once a week, were deployed in the Oyashio
and Kuroshio Extension (KE) in order to examine the circulation, formation site and time scale of newly formed North Pacific
Intermediate Water (NPIW). The floats were deployed in February or May 2001, and the data from their deployments to December
2002 are analyzed here. Four of the six floats were deployed near the KE axis at around the first meander crest, and they
moved eastward to 157°E–176°W at latitudes of 30°N–45°N. The other two floats deployed in the Oyashio water with low-potential
vorticity near the south coast of Hokkaido moved southward to reach the KE front and then moved eastward to the same region
as the first four floats. The temperature and salinity at 26.7 σθ measured by the profiling floats indicate that the source waters of NPIW, Oyashio and Kuroshio waters are drastically mixed
and modified in the mixed water region west of 160°E. The floats were separated into the three paths east of 160°E between
the Kuroshio Extension front and the north of Water-Mass front (nearly subarctic front). New NPIW is judged to be formed along
these three paths since the vertical profiles of temperature and salinity are quite smooth, having a salinity minimum at about
26.7σθ along each path. Kuroshio-Oyashio isopycnal mixing ratios of the new NPIW are 7:3, 6:4 and 5:5 at 26.7σθ along the southern, middle and northern paths, respectively. Potential vorticity converges to about 14–15 × 10−11 m−1s−1 along these paths. The time scale of new NPIW formation is estimated to be 1–1.5 years from the merger of Oyashio and Kuroshio
waters to the formation of the new NPIW.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
14.
Takanori Iwao Masahiro Endoh Nobuyuki Shikama Toshiya Nakano 《Journal of Oceanography》2003,59(6):893-904
In order to examine the formation, distribution and synoptic scale circulation structure of North Pacific Intermediate Water
(NPIW), 21 subsurface floats were deployed in the sea east of Japan. A Eulerian image of the intermediate layer (density range:
26.6–27.0σθ) circulation in the northwestern North Pacific was obtained by the combined analysis of the movements of the subsurface floats
in the period from May 1998 to November 2002 and historical hydrographic observations. The intermediate flow field derived
from the floats showed stronger flow speeds in general than that of geostrophic flow field calculated from historical hydrographic
observations. In the intermediate layer, 8 Sv (1 Sv ≡ 106 m3s−1) Oyashio and Kuroshio waters are found flowing into the sea east of Japan. Three strong eastward flows are seen in the region
from 150°E to 170°E, the first two flows are considered as the Subarctic Current and the Kuroshio Extension or the North Pacific
Current. Both volume transports are estimated as 5.5 Sv. The third one flows along the Subarctic Boundary with a volume transport
of 5 Sv. Water mass analysis indicates that the intermediate flow of the Subarctic Current consists of 4 Sv Oyashio water
and 1.5 Sv Kuroshio water. The intermediate North Pacific Current consists of 2 Sv Oyashio water and 3.5 Sv Kuroshio water.
The intermediate flow along the Subarctic Boundary contains 2 Sv Oyashio water and 3 Sv Kuroshio water.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
基于个体模型的东海鲐鱼渔场形成机制研究 总被引：4，自引：2，他引：2
鲐鱼Scomber japonicus资源丰富,在我国近海渔业中占有重要地位。其渔场的形成受海洋环境的制约,本文确定鲐鱼运动和物理环境之间的响应关系,建立起了基于个体的东海鲐鱼生长洄游模型。结果显示,鲐鱼集群分布与捕捞生产渔场基本吻合,鲐鱼聚集主要受台湾暖流、大陆沿岸水、黑潮影响,往往集群在一定温度范围内并在冷暖交汇区温盐梯度大偏暖水一侧。在台湾暖流和沿岸水交汇的锋面附近、台湾暖流暖水舌前端、黑潮与中国大陆沿岸水形成的潮境区域均有大量的鲐鱼聚集,并形成渔场。产卵位置的变动使偏西产卵位置的鲐鱼由于受台湾暖流影响较大,鲐鱼会呈长带状大量聚集在台湾暖流和沿岸水的锋面附近,并使在台湾暖流暖水舌前端的聚集数量增多,而偏东的产卵的鲐鱼受黑潮影响较大,聚集分布范围较大,会使黑潮形成的锋面附近聚集数量增多,而使台湾暖水舌的前端的聚集量减少。正常产卵位置在生存率方面是最佳产卵位置。研究表明鲐鱼所处空间位置不同,会影响其集群的位置,用数值模型验证了物理环境会对鲐鱼的洄游和渔场的形成产生影响。 相似文献
16.
西北太平洋环境变化对柔鱼冬春生群体资源丰度年间变化的影响 总被引：5，自引：0，他引：5
The neon flying squid Ommastrephes bartramii is an economically important species in the Northwest Pacific Ocean. The life cycle of O. bartramii is highly susceptible to climatic and oceanic factors. In this study, we have examined the impacts of climate variability and local biophysical environments on the interannual variability of the abundance of the western winter-spring cohort of O. bartramii over the period of 1995–2011. The results showed that the squid had experienced alternant positive and negative Pacific Decadal Oscillation(PDO) over the past 17 years during which five El Ni?o and eight La Ni?a events occurred. The catch per unit effort(CPUE) was positively correlated with the PDO index(PDOI) at a one-year time lag. An abnormally warm temperature during the La Ni?a years over the positive PDO phase provided favorable oceanographic conditions for the habitats of O.bartramii, whereas a lower temperature on the fishing ground during the El Ni?o years over the negative PDO phase generally corresponded to a low CPUE. The same correlation was also found between CPUE and Chl a concentration anomaly. A possible explanation was proposed that the CPUE was likely related to the climateinduced variability of the large-scale circulation in the Northwest Pacific Ocean: high squid abundance often occurred in a year with a significant northward meander of the Kuroshio Current. The Kuroshio Current advected the warmer and food-rich waters into the fishing ground, and multiple meso-scale eddies arising from current instability enhanced the food retention on the fishing ground, all of which were favorable for the life stage development of the western squid stocks. Our results help better understand the potential process that the climatic and oceanographic factors affect the abundance of the winter-spring cohort of O. bartramii in the Northwest Pacific Ocean. 相似文献
17.
Based on the surface drifters that moved out from the Sea of Okhotsk to the Pacific, the surface velocity fields of mean,
eddy, and tidal components in the Oyashio region are examined for the period September 1999 to August 2000. Along the southern
Kuril Island Chain, the Oyashio Current, having a width of ∼100 km, exists with velocities of 0.2–0.4 m s−1. From 40°N to 43°N, the Subarctic Current flows east- or northeastward with velocities of 0.1–0.3 m s−1, accompanied by a meandering Oyashio or Subarctic front. Between the Oyashio and Subarctic current regions, an eddy-dominant
region exists with both cyclonic and anticyclonic eddies. The existence of an eastward flow just south of Bussol' Strait is
suggested. The 2000 anticyclonic warmcore ring located south of Hokkaido was found to have a nearly symmetric velocity structure
with a maximum velocity of ∼0.7 m s−1 at 70 km from the eddy center. Diurnal tidal currents with a clockwise tidal ellipse are amplified over the shelf and slope
off Urup and Iturup Islands, suggesting the presence of diurnal shelf waves. From Lagrangian statistics, the single-particle
diffusivity is estimated to be ∼10 × 107 cm2s−1. 相似文献
18.
黑潮延伸体邻近区域中尺度涡特征统计分析 总被引：7，自引：3，他引：4
本文利用20年的卫星高度计资料,对黑潮延伸体邻近海区(25°—45°N,135°E—175°W)中尺度涡的统计特征以及季节变化进行了统计研究。基于涡旋自动识别方法,共识别出本区域3006个气旋涡轨迹和2887个反气旋涡轨迹,其平均周期分别为9.99周和11.00周,平均半径分别为69.5km和71.8km。长生命周期涡旋的平均半径、涡度、涡动能(EKE)和涡旋能量密度(EI)在生命周期内大致都经历了增大-基本保持不变-减小这三个阶段。绝大多数涡旋沿纬线向西移动,经向移动距离较小,气旋涡和反气旋涡在西向传播过程中都具有明显的向南(赤道)偏离趋势。涡旋的生成数量与总数量均在春夏季达到最多,且这一时期涡旋的平均涡度、EKE、EI处于较高水平。 相似文献
19.
The circulation of intermediate and deep waters in the Philippine Sea west of the Izu-Ogasawara-Mariana-Yap Ridge is estimated
with use of an inverse model applied to the World Ocean Circulation Experiment (WOCE) Hydrographic Program data set. Above
1500 m depth, the subtropical gyre is dominant, but the circulation is split in small cells below the thermocline, causing
multiple zonal inflows of intermediate waters toward the western boundary. The inflows along 20°N and 26°N carry the North
Pacific Intermediate Water (NPIW) of 11 × 109 kg s−1 in total, at the density range of 26.5σθ–36.7σ2 (approximately 500–1500 m depths), 8 × 109 kg s−1 of the NPIW circulate within the subtropical gyre, whereas the rest is conveyed to the tropics and the South China Sea. The
inflow south of 15°N carries the Tropical Salinity Minimum water of 35 × 109 kg s−1, nearly half of which return to the east through a narrow undercurrent at 15–17°N, and the rest is transported into the lower
part of the North Equatorial Countercurrent. Below 1500 m depth, the deep circulation regime is anti-cyclonic. At the density
range of 36.7σ2, – 45.845σ4 (approximately 1500–3500 m depths), deep waters of 17 × 109 kg s−1 flow northward, and three quarters of them return to the east at 16–24°N. The remainder flows further north of 24°N, then
turns eastward out of the Philippine Sea, together with a small amount of subarctic-origin North Pacific Deep Water (NPDW)
which enters the Philippine Sea through the gap between the Izu Ridge and Ogasawara Ridge. The full-depth structure and transportation
of the Kuroshio in total and net are also examined. It is suggested that low potential vorticity of the Subtropical Mode Water
is useful for distinguishing the net Kuroshio flow from recirculation flows.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
20.
中国近海鲐鱼资源时空分布与海洋净初级生产力的关系研究 总被引：2，自引：0，他引：2
海洋净初级生产力影响了浮游动植物的空间分布和丰度，因此决定了海洋渔业的潜在产量。本文根据2006-2015年7-9月中国远洋渔业数据中心提供的中国近海鲐鱼捕捞数据和海洋净初级生产力遥感数据，以单位捕捞努力量渔获量（CPUE）表征资源丰度，以经度和纬度重心表征空间分布，分析研究了鲐鱼资源丰度和空间分布与海洋净初级生产力的关系。研究结果表明，2006-2015年鲐鱼产量、CPUE、经度和纬度重心呈现明显的月份和年际变化，7-9月渔场内净初级生产力空间分布模式不同。频率分布结果表明7-9月鲐鱼对应的适宜净初级生产力浓度范围分别为300~500 mg/（m2·d）（以碳计，下同），300~400 mg/（m2·d），300~400 mg/（m2·d）。相关分析结果表明，鲐鱼资源丰度与适宜净初级生产力海域范围比例呈显著正相关，且鲐鱼纬度重心与适宜净初级生产力海域平均纬度呈显著正相关关系，这表明渔场内的净初级生产力大小和分布模式显著影响鲐鱼的资源丰度和渔场重心位置。在鲐鱼主要分布海域25°~30°N，120°~130°E范围内，鲐鱼资源丰度与净初级生产力大小呈显著负相关关系。此外，不同气候条件下鲐鱼渔场净初级生产力大小变化不同，2007年和2010年强拉尼娜年份以及2009年中强厄尔尼诺年份鲐鱼渔场范围海洋净初级生产力降低，但适宜的海洋净初级生产力范围增大，导致鲐鱼资源丰度上升；而2015年超强厄尔尼诺年份鲐鱼渔场范围内海洋净初级生产力上升，但适宜的海洋净初级生产力范围显著减小，因此鲐鱼资源丰度相对降低。研究表明，中国近海鲐鱼资源时空分布与海洋净初级生产力具有显著关联。 相似文献