胶州湾及周边海域大气和海水中N_2O和CH_4的分布及海气交换通量

分别于2006年8月,12月和2007年4月,10月采集胶州湾及周边海域大气和海水样品,对氧化亚氮(N2O)和甲烷(CH4)浓度进行了测定,并设置1个连续站进行24 h连续观测.结果表明:大气中N2O春、夏、秋、冬的平均浓度(体积分数)分别为(3.17±0.03)×10-7,(3.24±0.15)×10-7,(3.19±0.02)×10-7和(3.08±0.25)×10-7;大气中CH4春、夏、秋、冬的平均浓度(体积分数)分别为(1.89±0.04)×10-6,(1.79±0.04)×10-6,(2.09±0.21)×10-6和(2.01±0.09)×10-6.胶州湾表、底层海水中N2O和CH4的浓度和饱和度表现出明显的季节变化,其中N2O浓度和饱和度冬季最高,春、秋季次之,夏季最低;CH4浓度和饱和度夏季最高,冬季最低.利用Liss and Merlivat(1986)公式和Wanninkhof(1992)公式估算出胶州湾海域N2O的年平均海-气交换通量分别为(11.16±14.15)和(22.42±27.56)μmol m-2·d-1;CH4分别为(7.75±6.19)和(17.76±14.84)μmol m-2·d-1.胶州湾大部分海域表层海水中N2O和CH4呈过饱和状态,是大气中N2O和CH4的净源.     

春、夏季长江口及邻近海域溶解甲烷的分布与释放通量

分别于2012年3和7月对长江口及其邻近海域进行了大面调查,测定了表、底层海水中溶解甲烷浓度,并对其海-气交换通量进行了估算。结果表明,春、夏季表层甲烷的平均浓度分别为(28.33±38.33)和(19.92±19.18)nmol·L-1,甲烷浓度从内河口向外海逐渐降低。长江口溶解甲烷浓度和饱和度有明显季节变化,其中春季内河口甲烷浓度和饱和度高于夏季,但外河口及邻近海域则相反,这主要是温度和长江冲淡水中甲烷浓度的季节差异造成的。该海域溶解甲烷的分布受陆源输入影响显著,夏季长江冲淡水影响范围较春季更广,但由于稀释效应夏季甲烷浓度低于春季。夏季沉积物的释放对河口区甲烷的贡献较春季更为明显。调查期间该海域溶解甲烷都处于过饱和状态,是大气甲烷的净源;根据W92公式初步估算出长江口及其邻近海区年释放CH4量约为8.81×108 mol·a-1,占全球海洋年释放量的0.08%,远高于其面积比0.01%,因此该海区是甲烷产生和释放的活跃海域。     

2009年8月底长江口海水中甲烷的分布与释放通量

于2009年8月27日至9月2日对长江口海域进行了大面调查, 采集了表层和底层海水样品, 对溶解甲烷（CH4）浓度进行了测定。结果表明, 夏季长江口海域表、底层溶解甲烷的浓度分布特征基本一致, 即从近岸向远海逐渐降低, 底层浓度约为表层的2 倍。利用Liss and Merlivat（1986）公式、Wanninkho...     

渤海主要温室气体与海水pCO2环境特征

通过对渤海主要温室气体及海水二氧化碳分压的调查与研究,分析了渤海区底层大气二氧化碳(CO2)、甲烷(CH4)和二氧化碳分压(pCO2)的时空分布特征;渤海大气CH4含量春、夏、秋、冬季均值分别为2085、1974、2056和2060×10-9nl/L,各季节高值区均出现在黄河口邻近海域;黄河口邻近海域大气较高浓度的甲烷可能是渤海沿岸城市夏季出现高值的重要原因;渤海区大气二氧化碳浓度在2006年-2009年呈增高的趋势,2009年9月渤海中、北部海水pCO2在285～617μatm之间变化,渤海中部海水pCO2明显低于辽东湾内海水pCO2,研究区CO2海气通量-5.9～13.4mmol.m-2.d-1在之间,人类活动以显著影响到渤海的碳汇能力。     

桑沟湾春、秋季溶存CH4的分布及海-气交换通量

分析2013-10,2014-05和2015-05对桑沟湾3个航次的调查中采集的表、底层海水样品,研究该海域海水中溶解CH_4的分布特征及海-气交换通量。结果表明:春、秋季桑沟湾水体中CH_4浓度范围为3.0356.4nmol·L~(-1),底层浓度高于表层。由于水温的季节变化和陆源输入的影响,秋季表、底层平均CH_4浓度是春季的37倍。受养殖活动的影响,贝藻混养区表、底层CH_4均高于其他养殖区和湾外。2013-10,2014-05和2015-05桑沟湾表层海水CH_4的平均饱和度分别为(2 704±2 532)%,(330±276)%和(858±417)%,表现为秋季高于春季。根据W2014公式估算出桑沟湾春、秋季表层海水CH_4海-气交换通量范围为3.919.9μmol·m~(-2)·d~(-1),根据N2000公式估算出春、秋季表层海水CH_4海-气交换通量范围为5.520.6μmol·m~(-2)·d~(-1),表明春、秋季桑沟湾是大气CH_4的源区。     

桑沟湾溶存N2O的分布和海气交换通量的季节变化

于2006年4月至2007年1月对桑沟湾海域进行了4个航次的调查,采集表层海水样品,研究了该海域表层海水中溶解N_2O的分布特征及海气交换通量的季节变化,结果表明:桑沟湾表层海水中溶解N_2O浓度和饱和度存在一定的季节性变化,浓度表现为冬季最高而饱和度为夏季最高.利用Liss和Merlivat公式(LM86)以及Wanninkhof公式(W92)估算了该海湾海水中N_2O的年平均海-气交换通量,分别为0.2 μmol/(m~2·d)±0.1 μmol/(m~2·d)和1.5 μmol/(m~2·d)±1.0 μmol/(m~2·d).     

夏季渤海悬浮物粒径与浓度分布特征研究

为研究夏季渤海悬浮物粒径与浓度分布特征,我们利用现场激光粒度仪LISST于2015年6月、7月和8月在渤海海域进行了264个站位的悬浮物观测。观测结果表明,夏季渤海悬浮物存在左峰型(峰值范围在4-20μm)、右峰型(峰值范围在100-250μm)、双峰型和混合型4种主要粒径分布形态。悬浮物平均粒径和体积浓度空间分布都是近岸高,外海低;底层高,表层低。夏季渤海悬浮物浓度在6月、7月和8月存在显著变化,其中渤海表层、10m层和底层悬浮物体积浓度变化程度最大的海区分别为莱州湾、渤海中部海区和渤海湾,变化幅度分别为207%,240%和97%。     

獐子岛养殖海域颗粒有机碳、颗粒氮的时空分布特征

2011年8月、10月、12月和2012年4月对大连獐子岛养殖海域共14个站位进行了大面调查。对其中颗粒有机碳(POC)和颗粒氮(PN)的时空分布特征进行了研究。结果表明,獐子岛养殖海域水体中POC质量浓度的季节变化趋势是:夏季秋季春季冬季。夏季POC质量浓度最高,表、底层的质量浓度分别为0.159~1.672 mg/L和0.045~0.834 mg/L,平均值分别为(0.867±0.451)mg/L和(0.319±0.204)mg/L。冬季表、底层POC质量浓度最低,表、底层POC质量浓度分别为0.020~0.530 mg/L和0.061~0.458 mg/L。平均值分别为(0.240±0.125)mg/L和(0.221±0.129)mg/L。四个季节的POC质量浓度平面分布较为均匀。PN质量浓度的季节变化趋势是:夏季秋季冬季春季。夏季PN的质量浓度最高,表、底层PN的质量浓度分别为0.026~0.439 mg/L和0.020~0.393 mg/L,平均值分别为(0.193±0.067)mg/L和(0.172±0.060)mg/L。春季表、底层PN质量浓度最低,表、底层PN质量浓度分别为0.059~0.178 mg/L和0.024~0.212 mg/L,平均值分别为(0.120±0.047)mg/L和(0.100±0.050)mg/L。PN与POC的分布特征相似,空间分布均匀。叶绿素a(Chl-a)质量浓度的变化趋势为:夏季秋季春季冬季。POC、PN和Chl-a的垂直分布规律相似,春季底层质量浓度高于表层,夏秋两季表层质量浓度高于底层,冬季表、底层质量浓度基本一致。根据C/N以及POC/Chl-a的比值对POC的来源进行初步分析,表明该海域的POC主要来源于海洋生物,并且受陆源的影响较小。     

珠江口及海南岛东南海域海水中氨基酸的分布及其对有机物降解指示的研究

于2021年8月对珠江口及海南岛东南海域海水中的总溶解态氨基酸(THAA)、溶解有机碳(DOC)、有机氮(TN)和叶绿素a(Chl a)的浓度及分布进行了系统的调查研究。结果表明,调查站位海水中THAA的浓度范围为0.68～4.22μmol/L,平均浓度为(1.69±0.98)μmol/L,呈现近岸高、远岸低的分布趋势;垂直分布上,氨基酸浓度均呈现出随深度增加逐渐减小的特征。THAA浓度分布与天冬氨酸(Asp)/β-丙氨酸(β-Ala)和谷氨酸(Glu)/γ-氨基丁酸(γ-Aba)的比值具有显著正相关性,表明细菌活动对THAA的分布以及降解有重要影响。细菌源有机碳对DOC的贡献率约(13.04%±4.50%),呈现出近岸低于远岸、表层高于底层的特征。氨基酸中碳对有机碳的贡献率(THAA-C%)的分布趋势为近岸低于远海,说明近岸站位有机物降解程度更大。降解指数(DI)和活性指数(RI)也和THAA-C%呈现了相似的分布趋势,在调查海域的东部和珠江口近岸海域出现了高值区。垂直方向上,珠江口附近的S8—S14断面底层相对于表层降解因子的值更低,表明底层海水中的有机物降解程度更高,而海南岛东南...     

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±...     

Size-fractionated uranium isotopes in surface waters in the Jiulong Estuary in China

Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium （ 〈 0.4 μm） exis- ted in the low molecular mass fraction （ 〈 10 000 u）, and the colloidal uranium-238 （10 000 u -0.4 μm） only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases （ 〉 0.4 μm）, the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows： 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows ： 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value （1.0）. The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the partic     

夏季珠江口沉积物中营养盐剖面分布和界面交换通量

通过对夏季珠江口区域沉积物间隙水营养盐剖面分析,调查了营养盐含量分布和特征,探讨了有机物的降解特性、营养盐的底部通量估算和作用.结果表明,珠江口沉积物间隙水中营养盐以高含量铵盐为主要的存在形式,沉积物中有机物的降解反应主要在厌氧状态下进行,底部水体铵盐的增加来源于底部沉积物有机质的降解释放,而且对水体的营养盐循环有较大的贡献.     

Recent progress in submarine geosciences in China

In China submarine geosciences represents a newly established discipline of oceanography, focusing on the oceanic lithosphere, and its interface with the hydrosphere and biosphere. Recently, supported by the National High Technology Research and Development Program and other high-tech development projects, significant progress has been made in the development of advanced technologies and equipment. This en- ables the scientists in China to carry out explorations of the international seabed area in the Pacific Ocean and on the Southwest Indian Ridge. In addition, they have been active in the research activities associated the mid-ocean ridges and western Pacific marginal seas. It is anticipated that this research field will continue to be highly fruitful in the near future.     

湄洲湾夏季的初级生产力

湄洲湾１９９２年夏季的叶绿素ａ，三磷酸腺苷，碳比积累速率，初级生产力的变化范围和均值分别为０．４５－４．７２，１．４９ｍｇ／ｍ＾３；０．１２－１．０７，０．３１μｇ／ｄｍ＾３；０．０６－０．５８，０．３４ｄ＾－１；０．０７－０．３４，０．２１ｍ／（ｍ＾２．ｄ）。叶绿素ａ与三磷酸腺苷之间。初级生产力与碳比积累速率之间均呈正相关关系。叶绿素ａ三磷本能腺苷的比值为４．８，湄洲湾夏季浮游植物的生长受氮不足     

Challenges in cross-sectoral marine protection in Europe

Marine environment protection in Europe faces a number of challenges. One is the coordination of relevant sectoral policies — such as agricultural and fisheries policies — with regard to marine protection objectives. The question in the following is on how marine protection issues can be more closely integrated in sectoral policies under the conditions prevailing at present. In particular the strength and weaknesses of the Marine Strategy Framework Directive (MSFD) as the key instrument for marine environment protection in Europe are analyzed in this context. In particular, the MSFD does not adequately address all sectors and policies which are relevant to marine environment protection. One possible means of giving the MSFD greater influences on other policies of relevance to marine waters is to integrate the objectives established under the MSFD in the European maritime policy. The aim should be to require the further development of sectoral policies to take unrestricted account of the objectives of the MSFD implementation process. But also other instruments of marine policy such as maritime spatial planning and marine protected areas are crucial to advance the protection of European seas.     

Recent advances in marine technology in Canada

Much of the recent Canadian activity in marine technology has focused on development of capabilities in Arctic waters, and on the update and replacement of naval vessels. This paper describes some of the significant projects and programs now under way, and suggests future research and development requirements.     

一氧化氮在浮游植物中的研究进展

对一氧化氮在浮游植物中的研究进展进行了归纳,总结了一氧化氮对浮游植物生长的影响,探讨了浮游植物中一氧化氮的产生机制,并对今后的研究重点提出展望。     

Seasonality in nutrient concentrations in Galveston Bay

In order to investigate factors controlling nutrient cycling in the shallow and turbid coastal ecosystem of Galveston Bay, data from: (1) the Texas Water Commission (TWC) database 1980–1989, and (2) salinity transects in 1989 and 1993 are presented and analyzed. Statistical regression and time-series analysis were carried out on data acquired by TWC between 1980 and 1989, in an attempt to establish seasonally of nutrient and chlorophyll-a (chl.-a.) concentrations in the bay and to determine factors which regulate these concentrations.A strong seasonality was found for phosphorus and chl.-a. in the upper and mid-bay stations. A recurring maximum for phosphate occurred in September and a chl.-a. maximum occurred regularly in March–April. It is hypothesized that benthic regeneration of phosphorus at the end of summer is responsible for the phosphate maximum. The inverse correlation of the partition coefficient (K_d) for phosphate with the concentration of suspended particulate matter (SPM), coupled to a strong enrichment of phosphate in suspended particles at low SPM concentrations, indicates additional control by geochemical and physical processes such as particle sorting and/or particle-colloid interactions. Nitrate is inversely correlated with salinity at the upper and mid-bay stations, indicating the Trinity River is a major source.Nutrient concentrations in the lower bay (East and West Bay stations) are considerably lower and less predictable, as they are not correlated with salinity or temperature. Data from the 1989 and 1993 transects confirm the yearly maximum in phosphate concentration in late summer months, with peak concentrations in the upper Trinity Bay. It is concluded that despite possible phosphate buffering by physical and geochemical mechanisms, relatively large concentration maxima recur regularly every year during the summer, possibly caused by a benthic source of phosphate.     

中国海洋腹足类分类学研究进展——纪念中国科学院海洋研究所建所70周年

中国科学院海洋研究所建所70年来,在海洋贝类分类学研究领域取得了长足发展与进步,做出一系列开创性研究成果。本文综述了建所以来我所海洋腹足类分类学研究方面的主要进展,概述了取得的主要科研成果,分析了现代腹足类分类学研究的发展趋势以及面临的挑战,并对今后的发展提出了相应对策和建议。