浙闽沿岸潮余流的空间变化

利用非结构网格海洋环流模式(FVCOM),研究了浙闽沿岸潮余流的空间变化及其生成机制。结果表明,浙闽沿岸的潮余流具有明显的水平二维特征。根据潮余流的流速和方向,浙闽沿岸的潮余流可分为3个区域,自东北向西南,依次为区域I、区域II和区域III。区域I和区域III的潮余流较强,前者流速为0.6~2.5 cm/s,方向沿等深线指向西南;后者流速为0.5~1.5 cm/s,方向沿等深线指向东北。区域II的潮余流较弱,均小于0.6 cm/s,方向自岸向海逆时针旋转,离岸较近区域方向指向西南,离岸较远区域方向指向东北。结合浙闽沿岸的潮余流和海底地形进行分析,发现潮余流与地形β效应ddx1H成正比,这与前人研究获得的海底地形对潮流的整流机制相符合,表明浙闽沿岸海域陡峭的海底地形对潮流有明显的整流作用。     

胶州湾沉积物中一氧化碳的微生物产生及消耗研究

本研究通过测定一氧化碳(CO)原位浓度和地球化学参数并结合实验室培养实验,系统地探究了胶州湾沉积物中CO的产生及消耗过程。本文首次测定胶州湾沉积物孔隙水中CO的浓度在46.8～189.9 nmol·L^-1,培养实验结果表明三甲胺及甜菜碱的添加明显促进了CO的生物产生,2-溴乙烷磺酸钠(Sodium 2-Bromoethanesulfonate, BES)及钼酸钠等抑制剂的添加对CO消耗没有明显影响,表明产甲烷过程和硫酸盐还原过程不是消耗CO的主要微生物过程。硝酸盐浓度的增加对CO消耗有明显的抑制作用。研究结果可以为深化海洋沉积物中CO生物地球化学循环及微生物介导的碳循环过程认知提供基础支撑。     

海洋酸化和低氧及其节律性变化对海蜇碟状幼体的影响

人类生产活动引起的全球气候变化加剧作为重要的环境问题,海洋中pCO₂和溶解氧的失衡及富营养化加剧了许多沿海生态系统的酸化和低氧现象。海蜇(Rhopilema esculentum)为我国重要的渔业资源之一,具有食用价值及潜在药用价值。本研究评估了海蜇碟状幼体在海洋酸化和低氧及其昼夜节律变化胁迫下的生理响应:碟状幼体暴露于两个pH水平(酸化pH 7.6,正常pH 8.1)和两个溶解氧水平(低氧2mg·L^–1,常氧7mg·L^–1)维持7d,胁迫因素维持恒定或昼夜节律性变化,测定其伞部直径、收缩频率及酸碱平衡、免疫和抗氧化相关酶活力。研究表明,海洋酸化和低氧在不同程度上影响海蜇碟状幼体的生理代谢和生长发育,且酸化和低氧之间表现出部分拮抗作用,昼夜波动的暴露模式对海蜇碟状幼体的损伤程度大于恒定的暴露模式。     

浙闽沿岸流消退时期的浮游植物群落结构特征

浙闽沿岸流对台湾海峡的水文环境意义重大.依据国家海洋局"908"补充调查专项,通过对覆盖浙闽沿岸流海洋锋面过程的海洋生物调查研究,于2008年4月实施针对浙闽沿岸流消退时期(春季)台湾海峡锋面海域的浮游植物取样分析.结果共记录3门41属86种,其中硅藻35属76种.甲藻5属9种,蓝藻1属1种.种类组成以暖水性种类和广布...     

中小河流对长江水下三角洲远端泥沉积的贡献:以椒江和瓯江为例

海洋沉积物的来源、输运过程及其归宿一直是海洋沉积学的重要研究课题。浙闽沿岸泥区的沉积物主要来自长江及浙闽沿岸的中小河流,对后者的贡献量进行定量化分析是相关研究比较薄弱的环节,这个问题的难点可能是缺乏同时指示"物源"和"供应量"两个指标的示踪物。本文以椒江和瓯江这两条河流对浙闽沿岸泥区的贡献为切入点,运用了粒度端元和黏土矿物两种示踪指标进行研究,目的有两个:一是综合评价两种示踪指标的效率,二是定量化地了解中小河流对浙闽沿岸泥区的贡献。借助端元粒度分析模型对浙闽沿岸泥区的表层样粒度数据进行分解,划分出4个不同的端元,结果显示,EM1端元表现出长江来源的属性,EM2端元表现出椒江和瓯江等沿岸中小河流来源的属性,EM3端元可能来源于研究区南部并有向北输送的趋势,EM4端元可能来源于陆架中部的残留砂沉积区。基于特征粒级的进一步分析表明,研究区6个站位的柱样沉积物中都出现了第一特征粒级,在3.91~9.29 μm之间,推测与长江口外悬浮颗粒物有关,并认为柱样所在的区域都会受到长江入海泥沙的影响。黏土矿物由于具有粒度依赖性,在定量探讨椒江与瓯江的泥沙贡献量时,只能指示小于2 μm的细颗粒物的贡献量,而粒度端元作为一种"全粒度"的指标,在相对封闭的系统内,可以同时解答"从哪里来"和"有多少"这两个示踪问题,是受限比较小的示踪物指标,未来在定量研究物源方面可能会有较大的作用。     

九龙江河-海系统夏季浮游植物磷胁迫研究

采用群落水平和细胞水平碱性磷酸酶活性(APA)相结合的方法,研究了2010年夏季(6-7月)九龙江河-海系统(河流-河口-邻近海域)浮游植物的磷胁迫,结果表明,单位叶绿素a的APA在河流下游区[(48.80±14.69)nmol/(h.μg Chl a)]显著高于河口区[(10.60±15.58)nmol/(h·μg Chl.a)]和邻近海域[(23.54±25.41)nmol/(h·μg Chl.a)],表明河流区的浮游植物磷胁迫显著高于河口区和邻近海域.三个区域高比例的游离态APA表明该水域浮游植物已较长时间处于磷胁迫状态.细胞水平的浮游植物荧光标记结果显示,河口区(20％±20％)与邻近海域(38％±20％)无显著差异(P＞0.05),此结果与群落水平APA结果相一致;但河口-邻近海域浮游植物的标记比例显著高于河流下游区(9％±3％)(P＜0.05).     

黄、东海秋季群落净生产力的分布特征及其影响因素

群落净生产力(Net Community Production, NCP)代表了总初级生产力与群落呼吸的差值,是衡量生物活动对上层海洋碳循环影响的重要指标。O₂/Ar比值消除了物理过程对海水中溶解氧(O₂)饱和度的影响,因此基于生物氧饱和度(ΔO₂/Ar)可以估算海洋混合层群落净生产力。本研究于2015年10月,首次利用膜进样质谱法走航获取了黄东海表层海水中高分辨率O₂/Ar数据,并估算了其NCP,探讨了其分布特征及影响因素。本航次观测到的Δ(O₂/Ar)范围为-30.21%～44.38%,平均值为(0.32±8.29)%,低值主要出现在长江口北侧,而长江口(11.75±13.75)%和浙闽沿岸(5.42±5.21)%的Δ(O₂/Ar)明显高于南黄海(-2.62±5.96)%和东海陆架区(-0.79±5.02)%。南黄海和东海陆架区平均NCP为(-9.24±23.15)和(-4.04±18.68) mmol·m^-2·d^-1<...     

秋季南海东北部表层水体固氮及其对初级生产力贡献

2014年10月在南海东北部利用~(15)N和~(14)C示踪法实测了28个站位表层固氮速率和初级生产力,结合温度、盐度、营养盐和叶绿素a(Ch a)分析了南海东北部表层水体生物固氮及其对初级生产力的贡献。结果表明,受珠江冲淡水影响最明显的站位(A1)肉眼可见大量丝状束毛藻(Trichodesmium),其固氮速率达3475nmol N·m–3·h–1,是其他站位固氮速率的1~3个数量级之多;其他站位表层固氮速率在4~213nmol N·m–3·h–1之间,平均固氮速率为77±54nmol N·m–3·h–1(n=27),固氮速率最低的站位出现在受中国沿岸流影响的台湾浅滩及其邻近海域。近岸(水深小于100m)站位表层固氮速率与温度显著正相关(R=0.68,n=11,p0.05),相对高温、高磷和低硝酸盐可能是珠江冲淡水影响站位出现高固氮速率的原因,低温低盐则可能是台湾浅滩及其邻近近岸区域出现低固氮速率的原因。初级生产力(14.19~0.17 mg C·m–3·h–1)从近岸区域到外海逐渐降低,平均为0.61±0.45 mg C·m~(–3)·h~(–1),最高站位出现在台湾浅滩,最低站位出现在深海区。固氮作用对初级生产所需氮的贡献率(0.08%~9.30%,平均3.90%±3.10%)从近岸到外海逐渐增加,表层水温高于26℃时,固氮对初级生产的氮贡献显著增加。以上结果表明,秋季南海东北部固氮和初级生产受珠江冲淡水和沿岸流等物理过程调控。     

木兰溪河口及邻近海域春季水文环境特征及悬沙输移机制分析

基于2016年春季航次观测数据,分析了木兰溪河口及邻近海域温度、盐度及浊度等水文环境要素特征;并运用通量机制分解法分析该区兴化湾南日水道连续观测站位资料,以揭示该海域悬沙输移的控制机制。结果表明,春季兴化湾及邻近海域温盐变化受木兰溪径流、浙闽沿岸流和台湾暖流共同控制,湾外东南侧海域受高温高盐台湾暖流控制,西北侧近岸海域受低温低盐的浙闽沿岸流显著影响。调查海域悬沙浓度总体较低,外海泥沙通过南日水道向兴化湾内输移,但净输运量非常有限,仅为0.32×10~(-4)kg/(m·s)。平流输沙与潮泵输沙是南日水道泥沙净输运的主要机制,底沙再悬浮作用较显著,且剪切扩散效应也不容忽视。     

渤海溶解CH4分布和通量的季节变化及其影响因素

甲烷(CH₄)是影响地球辐射平衡的主要温室气体,海洋是大气CH₄的自然源,而陆架等近海是释放CH₄的热点海域。于2021年4月、7月和10月对渤海进行了调查,以认识其分布特征并估算其海-气交换通量。春、夏和秋季表层海水CH₄浓度分别为(4.56±2.60)、(8.31±4.01)和(4.99±1.31) nmol/L,夏季明显高于春秋季。CH₄的垂直分布规律为底层普遍高于表层,不同站位的垂直分布空间差异较大。渤海CH₄分布主要受河流输入、油气泄漏、生物活动以及沉积物-水界面交换等因素的影响,其中黄河向渤海输入CH₄约为每月1.4×104～2.8×105mol,秋冬季沉积物-水界面CH₄交换通量范围为–4.0～0.42μmol/(m²·d),表明秋冬季沉积物既可能是渤海水体CH₄的源,也可能是其汇。春、夏和秋季渤海CH₄海-气交换通量分别为(1.1±...     

Hydrographical characteristics and oxygen isotopic signatures of water in a coastal environment (Mangalore) along the southeastern Arabian Sea

Coastal marine environments are important links between the continents and the open ocean. The coast off Mangalore forms part of the upwelling zone along the southeastern Arabian Sea. The temperature, salinity, density, dissolved oxygen and stable oxygen isotope ratio (δ¹⁸O) of surface waters as well as those of bottom waters off coastal Mangalore were studied every month from October 2010 to May 2011. The coastal waters were stratified in October and November due to precipitation and runoff. The region was characterised by upwelled bottom waters in October, whereas the region exhibited a temperature inversion in November. The surface and bottom waters presented almost uniform properties from December until April. The coastal waters were observed to be most dense in January and May. Comparatively cold and poorly oxygenated bottom waters during the May sampling indicated the onset of upwelling along the region. δ¹⁸O of the coastal waters successfully documented the observed variations in the hydrographical characteristics of the Mangalore coast during the monthly sampling period. We also noted that the monthly variability in the properties of the coastal waters of Mangalore was related to the hydrographical characteristics of the adjacent open ocean inferred from satellite-derived surface winds, sea surface height anomaly data and sea surface temperatures.     

台湾海峡1989年初冬海面温度场和流系的卫星遥感初析

应用NOAA卫星AVHRR热红外遥感数据,通过计算机运算处理获得的海面温度专题图象,对台湾海峡及其邻近海域1989年初冬海面温度场及流系(黑潮、台湾暖流、浙闽沿岸流、南海暖流及台湾浅滩上升流)进行初步分析,利用卫星遥感手段佐证了过去用传统海面船测方法得出的一些结论,并获得了一些与过去有异的结果,得出1989年初冬浙闽沿岸流可达福建泉州湾和厦门港附近等结论,同时发现了该海域流系边界形成的几处波长在30～100km不等的切变波.     

黄、渤海几种溶解态痕量金属(Cu、Ni、Co、Zn)分布特征及其影响因素

海水中的痕量金属在海洋生物地球化学循环中至关重要。本研究在严格采用痕量金属洁净(trace-metalclean)采样和分析测试技术的前提下,于2016年7月采集了渤海与黄海表、底层海水水样,获得黄、渤海几种痕量金属(Cu、Ni、Co、Zn)的空间分布特征。研究结果显示,黄、渤海海水中痕量金属的空间分布具有近岸高、远岸低的特点,体现了人类活动对近岸海域的影响,而其在局部海域的分布则受到沿岸流、冷水团、沉积物再悬浮过程以及生物过程等因素的影响。Cu、Ni、Co在黄、渤海海水中的分布特征较为类似,平均浓度由高到低依次为渤海北黄海南黄海,而溶解态Zn的分布则与其他几种金属不同,在黄、渤海平均浓度类似,整体偏低,具有其特殊性。本研究测定的几种痕量金属在黄、渤海海水中的浓度较以往报道数据偏低,其中易污染的痕量金属Zn的浓度更是低近1—3个数量级,体现了痕量洁净采样和测试方法的重要性。     

Metal distributions and their fluxes at the coastal boundary of a semi-enclosed ria

Water column samples have been collected in the outer channel of the Ferrol Ria (NW Spain) during four occasions over a tidal cycle. The objective was to study the exchange of dissolved and particulate Cd, Cu, Pb and Zn and particulate Al, Fe and Si between the ria and the adjacent coastal waters. This study provides the first extensive dataset on dissolved and particulate metal concentrations in the water column of a Galician ria. Typical concentrations of dissolved Cd (96 ± 31 pM), Cu (8 ± 4 nM), Pb (270 ± 170 pM) and Zn (21 ± 10 nM) were similar than in other European Atlantic shelf and coastal waters. The fraction of metals in the particulate phase followed the trend: Pb > Cu Zn > Cd. The outgoing water from the ria was enriched in dissolved and particulate Cu, Pb and Zn compared with incoming waters, whereas Cd concentrations were similar for both waters. The suspended particulate matter was composed of a mixture of marine and continental material. The latter end-member was found to arise from the metal-rich ria bed sediments, which is diluted by the dominant metal-poor marine end-member. The net output flux of Cu from the channel is balanced by the freshwater inputs to the ria, and the net Zn flux gave a positive output to coastal waters. For Pb, the net flux to the coastal waters is less than that input from the rivers, as a result of its particle reactivity and deposition in sediments. On the contrary, a net input flux of dissolved Cd from coastal waters was observed, highlighting the oceanic source of this metal in the Galician rias. Results from the budget calculations are in agreement with the differential geochemical behavior of these elements in coastal waters.     

Atmospheric-induced variability of hydrological and biogeochemical signatures in the NW Alboran Sea. Consequences for the spawning and nursery habitats of European anchovy

The north-western Alboran Sea is a highly dynamic region in which the hydrological processes are mainly controlled by the entrance of the Atlantic Jet (AJ) through the Strait of Gibraltar. The biological patterns of the area are also related to this variability in which atmospheric pressure distributions and wind intensity and direction play major roles. In this work, we studied how changes in atmospheric forcing (from high atmospheric pressure over the Mediterranean to low atmospheric pressure) induced alterations in the physical and biogeochemical environment by re-activating coastal upwelling on the Spanish shore. The nursery area of European anchovy (Engraulis encrasicolus) in the NW Alboran Sea, confirmed to be the very coastal band around Malaga Bay, did not show any drastic change in its biogeochemical characteristics, indicating that this coastal region is somewhat isolated from the rest of the basin. Our data also suggests that anchovy distribution is tightly coupled to the presence of microzooplankton rather than mesozooplankton. Finally, we use detailed physical and biological information to evaluate a hydrological-biogeochemical coupled model with a specific hydrological configuration to represent the Alboran basin. This model is able to reproduce the general circulation patterns in the region forced by the AJ movements only including two variable external forcings; atmospheric pressure over the western Mediterranean and realistic wind fields.     

流式细胞术检测海洋浮游异养细菌异质性的研究进展

海洋浮游异养细菌(以下称浮游细菌)存在个体间的异质性,对浮游细菌异质性的研究是理解细菌生产、代谢及其在生物地球化学循环中重要作用的基础。流式细胞术具有快速分析大量细菌个体的能力,除了用来分析样品中细菌的丰度外,流式细胞术和细胞染色技术结合,被用来研究自然海水中浮游细菌在细胞膜完整性、CTC(5-氰基-2,3-二(4-甲基苯基)四唑氯化物)呼吸功能和核酸含量三个方面的异质性。尽管国外已经有较多研究,但我国在这方面的研究尚比较缺乏,本文综述了自然海区浮游细菌这三项异质性的研究现状,介绍了不同海区(主要是近岸)浮游细菌的异质性及其随环境的变化,以期推动我国在此领域的研究工作。目前对其异质性的变化机制尚没有很好的理论解释,在全球变化的大背景下,针对大洋深海和极区,有关长期变化、全球变暖以及酸化等对浮游细菌异质性的影响研究需要加强。     

中国近海区域古菌群落结构研究概述

古菌作为海洋微生物的重要组成部分,是海洋生态系统中物质与能量传递的重要贡献者,在全球生物地球化学循环中扮演着不可或缺的角色。虽然目前绝大多数的古菌尚未获得纯培养,但近年来分子生物学技术的发展使人们认识到古菌参与甚至主导了海洋生源要素循环的关键过程。本文介绍了目前研究海洋古菌多样性的主要手段,包括:荧光定量PCR、16S rRNA基因扩增子高通量测序、宏组学以及单细胞测序等技术,系统地阐述了中国近海不同区域(包括辽河口、黄河口、渤海、南北黄海、长江口、东海北部、珠江口以及南海区域)海水及沉积物中的古菌群落结构和多样性特征。研究表明我国近海地区的主要古菌类群为广古菌门(Euryarchaeota)、奇古菌门(Thaumarchaeota)、乌斯古菌门(Woesearchaeota)和深古菌门(Bathyarchaeota)等,其生物地理学分布主要受到环境因子和距离因素的影响,且在河口和近海海域呈现出完全不同的分布特点。在此基础上,对未来的研究方向进行展望,为全面深入了解我国边缘海生态系统中古菌群落及其参与的生物地球化学循环奠定了基础。     

Sources of Cd, Cu, Ni and Zn in Portuguese coastal waters

In order to identify the major sources of trace metals (TM) in the Portuguese coastal waters, 58 surface water samples were collected during September 1988. The area sampled extended from the Tagus Estuary (down to a salinity of 25) to cape Ste Marie on the southern coast of Portugal. Dissolved metal concentrations in the fully marine waters ranged from 30 to 250 pM for Cd, 0.7–15 nM for Cu, 0.9–20 nM for Zn and 1.8–4.5 nM for Ni. Within the Tagus Estuary (salinity 25), concentrations increased to 3400 pM for Cd, 26 nM for Cu, 14 nM for Ni and 230 nM for Zn.The large-scale distribution of these metals is dominated by two strong continental sources, both probably linked to the exploitation of pyrite ores. In the Tagus Estuary, TM enrichments can be mostly attributed to a pyrite roasting plant located on the shore in front of Lisbon. Concerning the south Portuguese shelf waters, several hypotheses are proposed to explain their elevated metal concentrations. We particularly discussed the likely influence of the Tinto/Odiel rivers located 100 km eastward, an influence well known in the shelf waters of the Gulf of Cadiz. These rivers are extremely metal-rich because of acid mine tailings originating from their catchment. Between these two regions, upwelling of relatively metal-poor water largely contributes to the dilution of the continental inputs. Indeed, water exchanges on the shelf linked to the upwelling involve water fluxes 500 times higher than the Tagus River flow, and renew the coastal waters that are thus cleaned from terrestrial contamination. Contrary to many other upwelling systems in non-contaminated areas, the Portuguese upwelling does not act as a source of trace-metal enrichment of the continental margin waters.     

Trace metal concentrations in menhaden larvae Brevoortia patronus from the northern Gulf of Mexico

Whole body concentrations of Cu, Zn, Mn and Fe were measured in individual gulf menhaden larvae, Brevoortia patronus (11–18 mm standard length) from coastal waters of the northern Gulf of Mexico as part of a continuing project investigating the mechanisms of biological interaction and effect of trace metals in marine food webs. Larvae were collected at three different times between February 1981 and 1982 at two locations, offshore of Southwest Pass of the Mississippi River and offshore of Galveston, Texas.Fish at the Mississippi location had significantly (P≤0·05) greater concentrations of all metals compared with those from the Galveston location. No significant (P>0·05) differences in concentration were detected among the three sampling periods. Menhaden larvae had metal conentrations comparabe to other species of larval fish and zooplankton from the Gulf of Mexico and other coastal waters. Differences in metal concentrations in larvae from the two locations appear to be a subtle response of the fish to differences in the trace metal chemistries of the two coastal areas. Processes influencing metal concentrations are discussed.     

海洋酸化对浮游植物生理生态影响的研究进展

当前全球气候变化下的上层海洋变暖与酸化对以浮游植物为主的海洋生态系产生了重大影响,理解此背景下的海洋浮游植物生理生态响应,对我们理解和抑制全球气候变化具有重要意义。在全球大气二氧化碳分压（pCO₂）升高情景下,浮游植物通过光合作用、微生物循环等过程,通过不同功能群对海洋生源要素循环模式的改变,进而影响区域及全球海洋的生物地球化学循环。研究全球浮游植物对海洋酸化生理生态的响应使得我们对生物地球化学系统的认识更加全面、系统。