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1.
1997年夏季西北太平洋环流模拟   总被引:5,自引:1,他引:5  
采用1997年7月中日副热带环流合作调查资料,即“向阳红14”号、“东方红”两调查船CTD观测资料、日本TK和IK断面资料以及GTSPP同步资料,应用开边界情形的MOM2模式计算了西北太平洋21.875°~35.125°N,120.875°~137.125°E范围的环流,主要结果如下:在此期间,(1)黑潮在台湾以东并不存在东分支流向琉球群岛以东海域;(2)东海黑潮的流量约为30×106m3/s,日本以南黑潮流量最大约为70×106m3/s;(3)在21.875°~25°N之间大约有15×106m3/s的流量向西流去.速度分布与流函数分布均表明这一支向西的海流大约在冲绳岛西南分为3支,主要分支转向东北沿冲绳岛以东海域向东北流去;(4)琉球海流主要来自上述西向海流.  相似文献   

2.
Circulations east of Taiwan and in East China Sea and east of Ryukyu Islands during early summer 1985YuanYaochu;Cho-tengLiu;P...  相似文献   

3.
Characteristics and evolution of the Kuroshio frontal eddies and warm filaments are analyzed according to two series of satellite images (March 5 to 7, 1986 and April 14 to 16, 1988). The results show that the frontal eddies in the East China Sea are generated at the shelf break and move along the continental slope at a speed of 15 cm/s with the Kuroshio. The frontal eddies occur about every 10 d and evolve to be warm filaments a few hundred km in length and 30-40 km in width in the area west of the Yaku-shima. Meanwhile, the existence of the warm filament was also found in the area by analysing the hydrographic data in the area west of Kyushu during May 24-June 5, 1988.The Kuroshio warm filaments move westward opposite to the Kuroshio and then turn northward at the shelf break and become the main source of the warm water of the Tsushima Warm Current. A simple dynamic explanation for the process is presented in this paper.  相似文献   

4.
On the basis of hydrographic data obtained during two October cruises of 1995, a modified inverse method is used to compute the Kuroshio east of Taiwan and the currents east of the Ryukyu-gunto.The net northward volume transport(VT) of the Kuroshio through Section TK2-K2 southeast of Taiwan is about 57.8×106 m3/s.There are four current cores of the Kuroshio at Section TK2-K2.Its main core is near the south of Taiwan, and its maximum speed is about 257 cm/s at the surface.After the Kuroshio flows through Section TK2-K2, there are three branches of the Kuroshio.The main branch of the Kuroshio flows northward into Section TKa east of Su''ao.The second branch of the Kuroshio flows northward through Section TKa and then enters the East China Sea through the region between Yonakunijima and Iriomote-shima.The net northward VT of the Kuroshio through Section TK4 is about 21.6×106 m3/s.The eastern branch of the Kuroshio flows northeastward through the region between a stronger cyclonic eddy and a recirculating anticyclonic gyre, and then flows continuously northeastward to the region east of the Ryūkyū-guntō and becomes a part of the origin of the western boundary current east of the Ryūkyū-guntō.Another part of the origin of the western boundary current east of the Ryūkyū-guntō comes from a recirculating anticyclonic gyre.From the above, in the regions east of Taiwan end east of the Ryūkyū-guntō the pattern of circulation during October of 1995 differs from the pattern of circulation during early summer of 1985.There are several eddies of different scales in this computational region.For example, there is a meso-scale stronger cyclonic eddy whose center is located at about 23°N, 124°20''E.  相似文献   

5.
基于2000年5~6月在台湾岛以东海域调查获得的多波束全覆盖测深等地质和地球物理资料,对该海域海底地形特征进行了研究,探讨了构造对海底地形的控制作用及其构造地质意义.研究表明,琉球岛弧岛坡区和琉球海沟表现为典型的西太平洋沟-弧-盆体系控制下的构造地形;台湾岛东部岛坡等深线近南北向平行密集排列,地形坡度大,弧陆碰撞造就了该区独特的地形特征;花东盆地海底峡谷发育,其形成主要受基底起伏和走滑断裂的控制;加瓜海脊东西两侧水深和地形特征明显不同,但其基底可能属于花东盆地,加瓜海脊的东侧对应了两个不同性质板块的边界;西菲律宾海盆表现为北西向线状脊-槽相间排列,并遭受北东向转换断层的切割,根据海底地形、转换断层和磁异常条带的方向推测,研究区海底形成于距今60~45Ma的西菲律宾海盆北东-南西向扩张期.  相似文献   

6.
In this study, the inverse method is used to compute the Kuroshio in the East China Sea and southeast of Kyushu and the currents east of the Ryukyu Islands, on the basis of hydrographic data obtained during September-October, 1987 by R/V Chofu Maru. The results show that: (1)A part of the Taiwan Warm Current has a tendency to converge to the shelf break; (2) the Kuroshio flows across the section C3 (PN) with a reduced current width, and the velocity of the Kuroshio at the section C3 increases and its maximum current speed is about 158 cm/s, and its volume transport here is about 26×106m3/s; (3) the Kuroshio has two current cores at the sections C3 (PN) and B2 (at the Tokara Strait); (4) the currents east of the Ryukyu Islands are found to flow northward over the Ryukyu Trench during September-October, 1987. The velocities of the currents are not strong throughout the depths. At the section C2 east of the Ryukyu Islands, the maximum current speed is at the 699 m levei and its magnitude is 25 cm/s, and i  相似文献   

7.
我国东部海区及邻域1:1 000 000地质地球物理系列图将于2008年底出版,区域构造图是其中的主要专业图件之一。讨论了该专业图件的编图方法、地质构造单元的划分方法和主要地质构造单元。首次对黄海东海区进行了全面剥皮编图,剥去了Q+N2地层。对于沉积盆地用等厚度线表示出了新生界的厚度。地质构造单元划分方法是以板块构造理论为指导并以现今的构造特征为主要划分依据。板块内构造单元的划分是在总结国内外多种构造单元划分方法的基础上进行了修改完善,完成了对我国东部海区及邻域的地质构造单元的划分。区内一级构造单元为板块(太平洋板块、欧亚板块和菲律宾海板块),二级构造单元为构造域(东亚大陆构造域、东亚大陆边缘构造域和西太平洋构造域)。西太平洋构造域主要包括太平洋板块的西部及菲律宾海板块。欧亚板块在该区的部分可分为东亚大陆边缘构造域和东亚大陆构造域。东亚大陆边缘构造域由日本琉球岛弧、冲绳海槽弧后盆地、日本海弧后盆地等次级构造单元构成。东亚大陆构造域在该区内由中朝地块、扬子地块、华南地块等次级构造单元构成。各地块又可划分出盆地、隆褶带、隆起区等多个次一级地质构造单元。最低一级的地质构造单元为凸起和凹陷。  相似文献   

8.
In three sections in the Kara Sea, the contents of the dissolved and particulate organic carbon (the DOC and POC, respectively), as well as of the organic carbon of the bottom sediments (Corg) were determined. The contents of varied from 6.3 to 2400 μg/l for the DOC and from 0.84 to 12.2 mg of C/l for the POC. The average concentrations for all the samples tested amounted to 200 μg/l for the DOC (n = 78, σ = 368) and 2.7 mg/l for the POC (n = 92, σ = 2.7). The concentrations of Corg in the samples of the upper layer of the bottom sediments of the area treated varied from 0.13 to 2.10% of the dry substance at an average value of 0.9% (n = 21, σ= 0.49%). It is shown that the distribution of the different forms of organic matter (OM) is an indicator of the supply and spreading of the particulate matter in the Kara Sea and that the DOC and POC of the Kara Sea are formed under the impact of the runoff of the Ob and Yenisei river waters. It is found that the distribution of the OM of the bottom sediments in the surveyed area of the Kara Sea is closely related to their grain-size composition and to the structure of the currents in the area studied. The variations in the Corg content in the bottom sediment cores from the zone of riverine and marine water mixing represent the variability of the OM burial.  相似文献   

9.
The Shenhu area is one of the most favorable places for the occurrence of gas hydrates in the northern continental slope of the South China Sea. Pore water samples were collected in two piston cores (SH-A and SH-B) from this area, and the concentrations of sulfate and dissolved inorganic carbon (DIC) and its carbon isotopic composition were measured. The data revealed large DIC variations and very negative δ 13C-DIC values. Two reaction zones, 0–3 mbsf and below 3 mbsf, are identified in the sediment system. At site SH-A, the upper zone (0–3 mbsf) shows relatively constant sulfate and DIC concentrations and δ 13C-DIC values, possibly due to bioturbation and fluid advection. The lower zone (below 3 mbsf) displays good linear gradients for sulfate and DIC concentrations, and δ 13C-DIC values. At site SH-B, both zones show linear gradients, but the decreasing gradients for δ 13C-DIC and SO4 2− in the lower zone below 3 mbsf are greater than those from the upper zone, 0–3 mbsf. The calculated sulfate-methane interface (SMI) depths of the two cores are 10.0 m and 11.1 m, respectively. The depth profiles of both DIC and δ 13C-DIC showed similar characteristics as those in other gas hydrate locations in the world oceans, such as the Blake Ridge. Overall, our results indicate an anaerobic methane oxidation (AMO) process in the sediments with large methane flux from depth in the studied area, which might be linked to the formation of gas hydrates in this area.  相似文献   

10.
The nannofosssil assemblages have been analyzed in five cores taken from the Titanic area of the northwestern Atlantic (∼41°–42° N, ∼47°–50° W, water depths >3500 m) during cruises 41 and 43 of the R/V Akademik Mstislav Keldysh in 1998 and 2000. They correlate the host sediments with the upper Pleistocene-Holocene Emiliania huxleyi zone. The changes in the structure of the nannofossil assemblages and the lithological characteristics such as the content of biogenic CaCO3, the abundance of ice-rafted debris, and the grain-size composition were used for the high-resolution stratigraphy of sections with defining marine isotopic stages 1–3 of the last 24 kyr. A characteristic feature of the nannofossil assemblages from this area is their enrichment with the cold-resistant species Coccolthus pelagicus during the warm climatic stages and the lack of allochthonous coccolitophorid remains.  相似文献   

11.
The structure and distribution of the macrobenthic communities were studied in the southwestern Kara Sea. The material was collected in Baidaratskaya Bay in July 2007 and in a section running westward of the Yamal Peninsula in September 2007. The depths of the sampling stations ranged from 5 to 25 m in the Baidaratskaya Bay area and between 16 and 46 m in the Yamal section. A total of 212 benthic invertebrate species were recorded. In both areas, Bivalvia was the group with the highest biomass (54.88 g/m2 in the Yamal section and 59.71 g/m2 in the Baidaratskaya Bay area), while polychaetes were the group with the highest number of species (45 in the Yamal section and 64 the Baidaratskaya Bay area). Three major macrozoobenthic communities were recognized: the Astarte borealis community (20–46 m, the deepest sampling stations in both areas); the “medium-depth” community (10–20 m, extremely mosaic, usually dominated by Serripes groenlandicus); and the Nephtys longosetosa community (depth smaller than 10 m, characterized by low biomass and the absence of large bivalves and echinoderms). The western Yamal shallow-water communities were shown to be generally similar to those of Baidaratskaya Bay. The comparison of these results with those of the benthos censuses performed in 1927–1945, 1975, and 1993 showed that the benthic communities in the southwestern Kara Sea remained relatively stable during the second half of the 20th century and the early 21st century.  相似文献   

12.
Samples of O isotopic tracer were mlleMed at Sections P3,P25,PcM-t/2-E and PCM-1/2.w in both the Fast China Sea and the area to the east of the Ryūkyū-gunto during October-November,1991.Analytical results of the δ18O are as follows: (1) In the Kuroshio area,the δ18O isolines are almost parallel to the 200 m isobath.The value of δ18O is negative and reaches minimum mt the main axis of the Kuroshio,and increases on both sides.(2) In the Taiwan Warm Current (TWC) area there is a high δ18O tongue extending to the northeast.(3) In the area near the coast,the distribution of δ18O isoline shows that the Changjiang River runoff diffuses seaward and the land-ocean isotopic effect from the nearshore to the offshore.(4) The values of δ18O are from -1.0×10-3 to -0.5×10-3 in the shelf.(5) There is a low mre of δ18O value(<-1.6×10-3) at the 600 m layer in the Kuroshio area,which is quite in accord with the existence of a low salinity mre (S G 34.30) between the 600 and 800 m layers in the same area.Finally,the mrrelations of the δ18O with the salinity and temperature,the upwelling and so on are discussed.  相似文献   

13.
黄海镆铘岛海域海草床数量分布及其生态特征   总被引:1,自引:0,他引:1  
海草床是近海三大典型海洋生态系统之一,具有巨大的碳储备功能,并为众多海洋生物提供重要的栖息场所及食物来源,在维持近岸海洋生态系统平衡中发挥着重要的作用。2016年8月通过对黄海镆铘岛海域的现场调查,发现分布面积为272.84 ha的海草床主要种类为鳗草(Zostera marina)和红纤维虾形草(Phyllospadix iwatensis)。鳗草的分布面积约为177.23 ha,占总面积的65%,主要分布在镆铘岛沿岸的海参养殖池中,红纤维虾形草的分布面积约为95.61 ha,占总面积的35%,主要分布在沿岸的礁石上,呈明显的带状分布。鳗草的平均株高为(86.8±5.8)cm,平均植株密度和生物量分别为(364.0±14.2)株/m~2和(528.7±20.5)gDW/m~2;红纤维虾形草的平均株高为(112.8±3.8)cm,平均植株密度和生物量分别为(3087.0±35.4)株/m~2和(2320.0±26.6)gDW/m~2。红纤维虾形草的分布水深为(1.80±0.04)m,海草床的水体溶解氧含量较高,达到(10.4±0.1)mg/L,分布有鳗草的海参池塘的底质粒径为(4.6±0.1)mm。结合历史资料,发现该海域海草床退化现象十分严重,这除了受自然环境变化的影响外,与过度的人类活动干扰有关。并提出了海草床修复与保护的建议和对策,可为进一步研究与保护该区域海草床生态系统提供基础。  相似文献   

14.
李照  宋书群  李才文  俞志明 《海洋学报》2017,39(10):124-144
通过2013年3月和8月在长江口及其邻近海域进行的多学科综合调查,研究了枯水期和丰水期浮游植物的群落结构和空间分布特征,并探讨了影响其分布的环境因子效应。枯水期共发现浮游植物3门41属80种(不包括变种和变型),以硅藻为主,主要优势种为具槽帕拉藻(Paralia sulcata);浮游植物细胞丰度介于0.15×103~16.35×103 cells/L,平均值为(3.24±3.14)×103 cells/L;浮游植物细胞丰度在长江口外东北部海域形成高值,垂直变化较小,硅藻刻画了浮游植物的空间分布。丰水期共发现浮游植物4门67属135种(不包括变种和变型),甲藻物种数量和细胞丰度均升高,主要优势种为东海原甲藻(Prorocentrum donghaiense)和骨条藻(Skeletonema sp.);浮游植物细胞丰度介于0.2×103~1 925.45×103 cells/L,平均值为(41.67±186.00)×103 cells/L;浮游植物细胞丰度在长江口外形成南北两个高值区,随水深增加,细胞丰度逐渐降低。浮游植物的空间分布受长江口冲淡水影响,与盐度和浊度有显著的相关性;N/P比影响浮游植物群落结构,随着N/P比升高,甲藻的相对丰度升高,硅藻的相对丰度逐渐降低。浮游植物在层化水体的上层大量繁殖是底层低氧形成的必要条件,硅藻具有较高的沉降速率,因而以硅藻为主的群落更利于低氧的形成。  相似文献   

15.
The spatial and temporal effects of hot seawater (60–70°C) from a power station on nearby soft-bottom communities were analyzed in the protected area “Sebadales del sur de Tenerife” (SE coast of Tenerife, Canary Islands, NE Atlantic Ocean). The samples were taken during summer 2003 and winter 2004 from 12 to 20 m depth. The highest macrofaunal abundance and species diversity were found in the turbines. A specific community, characterized by the polychaetes Aponuphis bilineata and sabellids of the genus Chone and the amphipod Photis longicaudata, inhabited the surroundings of the power station turbines. Permanent current from sea effluent had majok impact over the macrofaunal community structure of the neighbouring bottom where no measurable responses to thermal disturbance were detected.  相似文献   

16.
The structure of the assemblages associated with the mussel aggregations of Bathymodiolus azoricus was investigated. The mussel beds were found on the hydrothermal vent fields on the Mid-Atlantic Ridge (the Menez Gwen, Lucky Strike, and Rainbow areas) at the depths of 850–2400 m. The community structure of the mussel bed assemblages varied between the studied areas. Large number of species was unique to Menez Gwen mussel beds; the most observed taxa were not specialized hydrothermal species. All the other, nonunique species were found for the Lucky Strike region. The lowest mussel assemblage structure evenness was observed in the shallowest area, the Menez Gwen area (850 m depth). We assume that two types of mussel assemblages—nematode-dominated and copepod-dominated ones—exist in the Lucky Strike field. The assemblages of B. azoricus differ significantly from the assemblages of B. thermophilus inhabiting the Pacific hydrothermal vents.  相似文献   

17.
研究了热带西太平洋雅浦Y3海山冬季和马里亚纳M2海山春季网采浮游植物群落结构,对调查区浮游植物的物种组成、优势种类、细胞丰度以及多样性指数进行了分析。结果表明,两个海山区共鉴定浮游植物4门50属219种,其中硅藻门30属106种,甲藻门17属112种,蓝藻门1属2种,金藻门2属3种。两个航次研究区浮游植物优势种均以链状硅藻如根管藻(Rhizosolenia)、半管藻(Hemiaulus)和角毛藻(Chaetoceros)等属的种类为主,此外太阳漂流藻(Planktoniella sol)、铁氏束毛藻(Trichodesmium thiebautii)以及部分角藻(Ceratium)物种优势度也比较明显。Y3海山区浮游植物细胞丰度介于1.60~16.61 cells/L,平均值为5.02 cells/L; M2海山区浮游植物细胞丰度介于1.36~10.20 cells/L,平均值为4.12cells/L。两个海山区浮游植物细胞丰度的分布趋势均受硅藻影响较大,甲藻细胞丰度相对较低。在属的水平上,角毛藻、根管藻、角藻和半管藻等属的细胞丰度对两个海山区浮游植物总细胞丰度的贡献较大。多样性指数方面, Y3海山区浮游植物群落香农-威纳指数H′(shannon-wiener index)介于3.95~4.69,平均值为4.30; M2海山区浮游植物群落香农-威纳指数介于3.23~4.46,平均值为3.83。两个海山区浮游植物群落多样性指数均处于较高水平,但站位间的变化不明显。目前,关于热带西太平洋海山区浮游植物群落结构的研究还非常缺乏,亟需后续研究的补充。  相似文献   

18.
By using existing data obtained in the offshore area from the Boso Peninsula to the Joban Coast, it was shown that the double structure of the Kuroshio Front — which is usually found along the northern edge of the Kuroshio Extension to the east 143°E (Nagataet al., 1986 ; Shinet al., 1988) — is hardly found at the edge of the Kuroshio when it is flowing along the Japanese coast or in the area to the west of 142°E. It was suggested that the cold and fresh water core beneath the density front of the double structure originates from the fresh and cold Oyashio Water which is captured beneath the Kuroshio Front just off the Kashima Coast. The double structure of the Kuroshio Front would be generated and developed very rapidly in the region between 142°E and 143°E just after the Kuroshio leaves the Japanese coast.  相似文献   

19.
以欧洲中期天气预报中心的23年再分析风场数据为基础,采用HIRHAM风场模式和SWAN海浪模型对南海北部海域的波浪场进行推算,并将南海北部海域的有效波高与厄尔尼诺指数作对比,探究两者的关系,分析结论如下:(1)南海海域波高具有较强的季节性变化特征,冬季波高大于夏季波高;(2)南海北部海域月平均波高与Niño3.4指数呈负相关,大部分海域呈中度相关,台湾和菲律宾之间的部分海域呈高度相关;(3)在强厄尔尼诺年,南海北部海域的有效波高明显偏小,且厄尔尼诺指数变化越大,波高越小;反之,在强拉尼娜年,南海北部海域的有效波高较大。  相似文献   

20.
2006年冬季北黄海网采浮游植物群落结构   总被引:6,自引:1,他引:5  
杜秀宁  刘光兴 《海洋学报》2009,31(5):132-147
根据2006年12月30日—至2007年1月17日北黄海的调查资料,对该海域浮游植物的种类组成、优势种、丰度及其分布和多样性等基本状况进行了分析。本次调查共鉴定浮游植物4门68属131种,主要以温带近岸和广布性种为主,其中硅藻有53属113种,占总种数的86.3%,甲藻有11属16种,占总种数的12.2%。浮游植物丰度平均值为88.89×104个/m3,硅藻丰度平均值为86.58×104个/m3,甲藻丰度平均值为2.28×104个/m3,硅藻丰度分布趋势决定了浮游植物丰度的分布趋势。辽宁南岸是浮游植物密集区,山东半岛北岸其次,而北黄海中部是浮游植物的稀疏区。优势种为:短角弯角藻(Eucampia zodiacus)、具槽帕拉藻(Paralia sulcata)、尖刺拟菱形藻(Pseu-do-nitzschia pungens)、密连角毛藻(Chaetoceros densus)、柔弱角毛藻(Chaetoceros debilis)、刚毛根管藻(Rhizosolenia setigera)。浮游植物群落Shannon-Weiner物种多样性指数平均值为1.80,Peilou均匀度指数平均值为0.42。与1959年1月相比,2007年1月北黄海浮游植物丰度由150.00×104个/m3降为88.89×104个/m3,下降了近41%,硅藻丰度由148.00×104个/m3降为86.58×104个/m3,而甲藻丰度由1.25×104个/m3上升为2.28×104个/m3,占浮游植物丰度的比例由0.8%上升为2.5%。主要优势种及优势属也发生了一定程度的变化,但浮游植物群落结构仍以硅藻为主、甲藻其次,浮游植物丰度总的分布格局变化不明显。  相似文献   

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