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111.
Since the Intermediate Oyashio Water (IOW) gradually accumulates in Sagami Bay, it can reasonably be supposed that the IOW
also flows out from Sagami Bay, even though it may be altered by mixing with other waters. We have occasionally observed a
water less than 34.2 psu with a potential density of 26.8 at the southeastern area off Izu Peninsula in July 1993 by the training
vessel Seisui-maru of Mie University. Observational data supplied by the Japan Meteorological Agency and the Kanagawa Prefectural
Fisheries Experimental Station show that the IOW of less than 34.1 psu was observed at northern stations of the line PT (KJ)
off the Boso Peninsula and to the east of Oshima in the late spring 1993. Based upon these observations, it is concluded that
the IOW flows out from Sagami Bay into the Shikoku Basin along southeastern area off the Izu Peninsula. The less saline water
(<34.2 psu) was also observed to the west of Miyake-jima during the same cruise, and the westward intrusion of IOW from south
of the Boso Peninsula to the Shikoku Basin through the gate area of the Kuroshio path over the Izu Ridge was detected. This
event indicated that the IOW branched south of the Boso Peninsula and flowed into Sagami Bay and/or into the gate area over
the Izu Ridge. The southward intrusion of IOW into the south of the Boso Peninsula is discussed in relation to the latitudinal
location of the main axes of the Kuroshio and the Oyashio.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
112.
113.
化学生态调控对鳌山湾氮磷营养盐的影响 总被引:2,自引:0,他引:2
鳌山湾,是一个营养类型特殊的海湾,湾中基本无径流输入,呈“C”字形,封闭性较强,水较浅,湾内主要有筏式扇贝养殖和底播贝类养殖,沿岸有滩涂池塘养殖.根据1996年11月至1998年5月的调查结果得知,鳌山湾海域为贫营养海域[1,2].为探讨贫营养海域进行化学生态调控的可能性,利用鳌山湾的封闭性,根据其水交换规律[3],于1999年6月首次对鳌山湾进行了全湾规模较大的化学生态调控试验,旨在有效提高鳌山湾的营养水平,为今后在贫营养海域合理发展海水养殖业提供科学依据,获得了十分理想的效果. 相似文献
114.
Ucan Osman N. Albora A. Muhittin Hisarli Z. Mümtaz 《Marine Geophysical Researches》2001,22(4):251-264
In this paper, residual and regional gravity and magnetic anomalies of Saros Bay are separated using wavelet method. Wavelet
is one of the modern, stochastic image approaches processing technique in electronics. The vertical, horizontal and diagonal
components of wavelet output are evaluated simultaneously and an underground model is obtained by suitable cross-sections.
Thus the geological and tectonic properties of Saros Bay are extracted. Our proposed model is confirmed by deep and shallow
seismic researches of Turkish Petroleum Cooperation (TPAO). The South-East region of Saros Graben is formed by strike slip
Ganos Fault and Anafartalar reverse Fault that lies on the east of Ganos Fault. On the Northwest region, there is strike slip
component fault resulting in the Enez Graben. Here we detected two new oval type geological structure, both of them starting
from the Eastern direction of Canakkale Dardanelles and but one of them continuing through Gelibolu Peninsuls, while the other
tending to the Enez Graben. We think that these structures are the ruins of a very old sea in this region.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
115.
Temporal change of clustered distribution in vertical profiles of three nutritional groups of planktonic ciliates, e.g. heterotrophic
naked ciliates, mixotrophic naked ciliates and heterotrophic loricated ciliates, was investigated by following a drifting
buoy in Toyama Bay on the Japan Sea coast of central Japan in summers of 1989 and 1990. Clustered distribution, represented
as the mode of population density in the vertical plane, occurred mainly in the oligotrophic upper layer (0–50 m depth) above
the subsurface chlorophyll-a maximum layer. Its clustered degree was stronger when the mode of population density in the vertical plane was formed at
shallower depth, while its longevity was shorter as mentioned above. Vertical distribution of ciliates during summer in Toyama
Bay is characterized by ephemeral clustered distribution, or in other wards, by rapid alternations of appearance and disappearance
of the clustered distribution. 相似文献
116.
Complexation of mercury by dissolved organic matter in surface waters of Galveston Bay, Texas 总被引:3,自引:0,他引:3
The chemical speciation of dissolved mercury in surface waters of Galveston Bay was determined using the concentrations of mercury-complexing ligands and conditional stability constants of mercury-ligand complexes. Two classes of natural ligands associated with dissolved organic matter were determined by a competitive ligand exchange-solvent solvent extraction (CLE-SSE) method: a strong class (Ls), ranging from 19 to 93 pM with an average conditional stability constant (KHgLs) of 1028, and a weak class (Lw) ranging from 1.4 to 9.8 nM with an average KHgLs of 1023. The range of conditional stability constants between mercury and natural ligands suggested that sulfides and thiolates are important binding sites for dissolved mercury in estuarine waters. A positive correlation between the estuarine distribution of dissolved glutathione and that of mercury-complexing ligands supported this suggestion. Thermodynamic equilibrium modeling using stability constants for HgL, HgClx, Hg(OH)x, and HgCl(OH) and concentrations of each ligand demonstrated that almost all of the dissolved mercury (> 99%) in Galveston Bay was complexed by natural ligands associated with dissolved organic matter. The importance of low concentrations of high-affinity ligands that may originate in the biological system (i.e., glutathione and phytochelatin) suggests that the greater portion of bulk dissolved organic matter may not be important for mercury complexation in estuarine surface waters. 相似文献
117.
海口湾的溶解氧及海水水质指标限制值问题 总被引:4,自引:0,他引:4
海水溶解氧对海洋生物的生存、生长和发育相当重要,与生物活动有着密切的联系,它的含量变化是反映生物生长状况的一个重要标志,同时也是污染监测的重要指标.海口湾是海南省的重点海域,1989年以来,陈春华等对海口湾的环境问题进行了大量的研究[1~6],本论文就海口湾的溶解氧监测结果进行分析,并发现了溶解氧水质标准限制值存在的问题.每年在该湾布设10余个站点进行污染监测,有必要对海口湾近7年监测结果进行综合分析. 相似文献
118.
大亚湾微表层和次表层海水营养盐的研究 总被引:11,自引:0,他引:11
根据1998年秋季(10、11月)、1999年春、秋季(4、5、10月)5个航次对大亚湾海区微、次表层的调查结果,分析了微表层海水对氮、磷、硅营养盐的富集概况,讨论了营养盐与环境因子的关系。结果表明:大亚湾海区微表层海水对氮、磷、硅营养盐均有富集作用,因海况及季节不同,富集因数(EF)与其他海区的有所差别;无论夏季或秋季,大亚湾海区微表层海水中无机氮都以NH4-N为主要存在形态;其余水层则以NO3-N为主要存在形态。结果还表明,微表层、次表层海水中NH4-N与BOD5、COD测值都呈高度显著正相关,与PO4-P和SiO3-Si含量均无相关,说明大亚湾海区水中含氮有机物较含磷有机物丰富。 相似文献
119.
120.
This study examined the phenology and ecological consequences of a benthic filamentous cyanobacterial bloom (Lyngbya majuscula) in Deception Bay (Moreton Bay, Queensland, Australia). Bloom initiation occurred in mid December 1999 and expanded to encompass an 8 km2 area by April 2000. Small fish and penaeid prawns (<25 cm total length) were quantitatively sampled through periods designated as before, during and after the bloom using a combination of pop-netting within mangroves and beam trawling over adjacent seagrass beds. Data on larger-bodied fish were compiled from daily fishing logs provided by local commercial fishers. Changes in dry mass of bloom material caught in nets and changes in water chemistry were also measured. Mean concentrations of ammonia-N in residual water within mangroves were several orders of magnitude higher in the affected area than in the control and dissolved oxygen was markedly lower in affected areas. Across the study area, mean density, live mass and number of species declined during the bloom, with fish assemblages using mangroves showing greater decline than assemblages using seagrasses. Response at the species level was highly variable; generally, epibenthic species showed a more sustained decline than demersals. Mean monthly fish catch was significantly lower in bloom than non-bloom years. This study has also demonstrated that throughout the bloom, the affected area continued to support a highly diverse and abundant fish and prawn assemblage, and probably maintained its function as an important nursery habitat for many species. 相似文献