Mineral composition of sediments from the Eastern Laptev Sea shelf and East Siberian Sea

The mineral composition of the heavy fraction in surface sediments of the Laptev and East Siberian seas has been analyzed. The multivariate statistics methods were used to define the main heavy mineral assemblages with outlining regional differences in their compositions and principal factors responsible for the formation of sediment mineral affinity in the study areas. It is shown that the distribution of the determined heavy mineral assemblages is controlled by the geostructural positions of sedimentation basins.     

宁德市东部海域浮游动物群落及其与水环境因子的关系

浮游动物在海洋生态系统中发挥重要作用,也是海洋食物链的主要环节。为科学保护和评价海洋生态环境和渔业资源,文章基于2016年春、秋季宁德市东部海域的相关调查结果,采用多样性指数、丰富度指数、均匀度指数和优势度指数以及去趋势对应分析法和冗余分析法,分析浮游动物群落及其与温度、pH值、溶解氧、无机氮、无机磷和化学需氧量6个水环境因子的关系。研究结果表明:春、秋季调查共鉴定浮游动物12类67种,季节和站位差异不大,均以水母类、桡足类和浮游幼虫为主;共出现优势种18种,春、秋季分别以桡足类和水母类为主,相同优势种仅有2种;3种指数分布无明显季节差异,但秋季指数总体较高;春、秋季浮游动物种类分别与各水环境因子呈正相关或负相关关系,其中温度是影响浮游动物种类的最主要水环境因子。     

Distribution and Feeding of Herbivorous Zooplankton in the Laptev Sea

Sampling was conducted along the quasi meridional transect at 130° E from the Lena River estuary to northern deep-sea regions of the Laptev Sea in September 2015. The latitudinal zonality and the impact of river runoff are manifested in the temperature and salinity distribution, concentration of particulate organic matter, and the structure of plankton communities. The differences in the chl a concentration and primary production along the transect are insignificant. The feeding rate of mesozooplankton herbivores was assessed by a fluorescence technique. The total consumption of phytoplankton biomass and primary production are estimated based on the feeding rate, abundance of zooplankton species, and their diel migrations. The daily grazing impact of zooplankton on phytoplankton biomass increases from 2% on the inner shelf to 3% on the mid-shelf, 5% on the outer shelf, and 10% in the deep-sea part of the basin. The consumption of primary production also increases: 1, 4.5, 5.7, and 13.9%, respectively. In the fall, the consumption of phytoplankton does not compensate the energy demands for respiration. The latitudinal zonality of the Laptev Sea appears not only in the hydrophysical water parameters and the structure of plankton communities, but also in their functional characteristics.     

楚科奇海浮游植物的分布与环境因子的关系

根据1999年7—8月“雪龙”号考察船在楚科奇海采集的样品,运用PRIMER软件分析该区网采浮游植物的分布特征及其与环境因子的关系。结果表明：楚科奇海浮游植物群聚可分为三个生态类群：北极-亚北极类群,主要分布于水深大于2000米且受北冰洋影响较直接的东北部浅水浮冰外缘;北方温带类群,主要分布于水深小于100米的中部浅水浮冰区：广温性类群,主要分布于通过白令海峡与北太平洋进行水交换的南部水域。该区浮游植物平面分布差异大,细胞密度站间变化范围为1．6×10^3～90680．2×10^4,物种多样性指数和均匀度站间变化范围分别为0．07～O．87和0．33～3．82。主成分（PCA）分析表明,对楚科奇海浮游植物分布起支配作用为水温和盐度。此外,由于该海区所处的特殊地理环境,浮冰的位黄及其物理状态（聚集、开裂和消融等）均会增加浮游植物分布的变异。     

Factors Affecting the Distribution and Diversity of Polychaetes in Amivrakikos Bay, Greece

Abstract. The polychaetc fauna was studied in 18 soft-bottom stations in Amvrakikos Bay of the Ionian Sea. Of the 146 species found many had single occurrences, which caused low similarity between stations. Mixing and renewal of water influenced the distribution of species and feeding types of polychaetes, while their diversity correlated with sedimentary structure. Water depth was the factor which accounted for the greatest variability in the data, whereas salinity had no discernible effect on the polychaetc fauna.     

渤海春季浮游细菌分布与生态环境因子的关系

研究了 1 999年 4～ 5月渤海水体浮游细菌分布与生态环境因子的关系。结果显示 ,渤海春季表层水体浮游细菌含量与水温和溶解性有机碳呈正相关 ,相关系数分别为 0 .6 0 1 (P<0 .0 1 )和0 .4 0 6 (P<0 .0 5 ) ,并与溶解氧含量呈负相关 ,相关系数为 0 .5 1 9(P<0 .0 1 ) ;底层水体浮游细菌含量与水温、溶解性有机碳 (dissolved organic carbon,DOC)、颗粒性有机碳 (particulate organic carbon,POC)和叶绿素 a含量呈正相关 ,相关系数分别为 0 .82 0 (P<0 .0 1 ) ,0 .6 6 1 (P<0 .0 1 ) ,0 .5 31 (P<0 .0 1 )和 0 .4 42 (P<0 .0 5 ) ,并与溶解氧含量呈负相关 ,相关系数为 0 .6 5 0 (P<0 .0 1 )。表明水温和DOC、POC含量是渤海水域浮游细菌含量的主要限制因子 ,而水体中的溶解氧 (dissolved oxygen,DO)含量与浮游细菌的含量有关     

黄海西北部浮游细菌生物量分布特征及其与环境因子的关系

分别研究了2006年7月(夏季)和2007年1月(冬季)、5月(春季)、10月(秋季)黄海西北部海域浮游细菌生物量的分布特征,探讨了它们与温度、盐度和Chl a含量之间的关系.结果表明,研究海区平均细菌生物量春、夏、秋和冬季分别为:41.083,8.34,16.68和6.20 mg/m3.4个季节表层细菌生物量分布均呈现出从辽东半岛近岸区域向外海逐渐降低的趋势.春、秋季除浮游植物Chl a外各生态因子与细菌生物量之间均无显著性相关关系.夏、冬季与温度、盐度和Chl a含量的相关性均不显著.     

渤海中部断面环境要素分布及其变化趋势

研究渤海的可持续发展.根据 1979～1999 年渤海中部断面温度、盐度、溶解氧、营养盐的调查资料,分析了它们的分布结构和20年来的变化趋势.结果显示断面各个要素冬季的垂向分布均匀,夏季有2个冷水中心,盐度、溶解氧、营养盐在冷中心位置也出现了类似的高值或者低值中心.各要素的距平图显示盐度有上升趋势,溶解氧含量下降,无机氮逐年增加,磷酸盐和硅酸盐夏季有下降的趋势,但是冬季没有明显的增加或者减少的趋势.     

中国南海表层沉积硅藻的分布及其与环境关系探讨

通过对中国南海62个站位表层沉积硅藻的分析,查明研究海区硅藻的种类组成及分布特点。共鉴定到硅藻56属的235个种(包括变种和变型),以热性外洋种为优势,伴有一定量的近岸广布种。总体上,南海硅藻丰度变化呈现从陆架向陆坡至海盆递增的趋势。根据表层沉积硅藻中具有指示意义的硅藻种的分布和生态变化,划分6个硅藻组合带,各组合分别反映不同的海洋环境,其分布主要受到海洋环流的影响,表现为黑潮暖流、印度洋暖水的入侵以及沿岸流对南海表层沉积硅藻分布的影响。与南海相邻海区硅藻种类比较结果表明,研究海区表层沉积硅藻种类组成与临近的菲律宾海域相似程度最大,其次是中国东海海域、太平洋东北部海域。     

春季南黄海、东海浮游植物群落结构与环境因子

2017年春季(04-20—05-09)在南黄海和东海海域(119°30′～125°00′E,26°00′～36°00′N)67个站位进行水文、化学和生物的综合调查,使用水采方法研究调查海域的浮游植物群落结构,并将群落数据与环境因子(温度、盐度和营养盐)进行相关性分析。调查中共鉴定出浮游植物4门55属146种,主要由硅藻和甲藻组成,还有少量的金藻和蓝藻,生态类型以温带近岸性和广布性物种为主。优势物种组成方面,南黄海和东海海域存在差异,其中南黄海海域优势物种为诺氏海链藻(Thalassiosira nordenskioldii)、太平洋海链藻(Thalassiosira pacifica)、微小原甲藻(Prorocentrum minimum)和具槽帕拉藻(Paralia sulcata)等,东海海域优势物种为柔弱伪菱形藻(Pseudo-nitzschia delicatissima)、具槽帕拉藻(Paralia sulcata)、柔弱角毛藻(Chaetoceros debilis)和具齿原甲藻(Prorocentrum dentatum)等。调查区浮游植物细胞丰度为(0.07～547.87)×10~3个/L,平均值为29.45×10~3个/L,高值区集中在南黄海中部和闽浙沿岸区域,其中在南黄海中部的10～30 m水层发生硅藻水华。与环境因子的相关性分析表明,南黄海海域浮游植物细胞丰度与硅酸盐和磷酸盐浓度呈现显著正相关性,与其他环境因子相关性不明显;东海海域浮游植物细胞丰度与温度和盐度呈现显著负相关性,与硅酸盐、铵盐和硝酸盐浓度呈现显著正相关性。调查区香侬-威纳多样性指数介于1.05～4.86,平均值为2.48,高值区出现在调查区的北部近岸区域;Pielou均匀度指数介于0.02～0.97,平均值为0.57,高值区集中在南黄海北部近岸区域和东海外侧区域。     

Distribution of trace and major elements in sediment and pore waters of the Lena Delta and Laptev Sea

Sediment cores collected during the SPASIBA expedition in 1991 were analysed for their trace- and major element concentrations. Leachable (0.1 N HCl) as well as residual concentrations were determined. Fe and Mn were measured in the interstitial waters to characterize redox conditions. Lateral distribution patterns of solid phase Cu, Cd, Ni, Pb and Zn show a small increase in concentration from the Lena Delta in seaward direction. In general concentrations of these metals are very low and similar to natural background values. With some exceptions, solid phase profiles with depth of all investigated elements do not show strong variations. No enrichment of Pb and Zn in surface layers was found. Remobilization processes and transport of particles enriched in Mn are responsible for Mn accumulation in a particular area. Pore-water concentrations of dissolved Mn in the latter sediments are very high (> 700 μM) and suggest strong Mn reduction directly below the sediment-water interface. In contrast to Mn, the depth profiles of Cd show a surface layer with lower concentrations and an increase deeper down the sediment. The C/N ratio in the sediment decreases from 13 in the Lena mouth to 9 in the more marine part of the Laptev Sea. Surface sediments in the Laptev Sea are very uniform and homogeneous and show only small concentration gradients.     

Trophic pathways and carbon flux patterns in the Laptev Sea

The Laptev Sea is a high-Arctic epicontinental sea north of Siberia (Russia) that is one of the least understood regions of the world’s ocean. It is characterized by a shallow and broad shelf plateau, high influx of river water, sediments and nutrients during summer, long-lasting sea-ice cover from October to May, and the formation of a narrow flaw-lead polynya off the fast-ice edge during winter.Here, we describe results of a German–Russian research project (1993-present), presenting the distribution patterns and dynamics of its marine flora and fauna, as well as pathways and processes of coupling between sea-ice, water-column and sea-floor biota.Three ecological zones are distinguished along a combined east–west and Lena-impact gradient, differing in the composition of pelagic and benthic communities. In general, high Chl a concentrations in the sediments indicate a tight coupling between sympagic and pelagic primary production and nutrient supply to the benthos throughout the entire Laptev Sea. However, there were pronounced regional differences between the ecological zones in magnitude of primary production and trophic dynamics. Primary production during the ice-free summer was highest in the estuarine zone most strongly influenced by the Lena River (210 mg C m⁻² day⁻¹). The western and northeastern Laptev Sea yielded 55 and 95 mg C m⁻² day⁻¹, respectively. Moreover, the zones differed in the partitioning of carbon flux between zooplankton and benthic food webs. In the Lena zone zooplankton carbon demand was about 31 mg C m⁻² day⁻¹ whereas in the western zone it was 21 mg C m⁻² day⁻¹ and in the eastern zone 4 mg C m⁻² day⁻¹. Total benthic carbon demand was 32 mg C m⁻² day⁻¹ for the Lena zone, 56 mg C m⁻² day⁻¹ in the western zone and 100 mg C m⁻² day⁻¹ in the northeastern zone.A carbon budget constructed for the Laptev Sea indicates that (1) a high proportion of primary production is channelled through the benthic trophic web, bypassing the pelagic trophic web, and (2) autochthonous primary production in the northeastern and western Laptev Sea might not be sufficient to fuel both pelagic and benthic secondary production and, hence, input of allochthonous organic carbon is required to balance the overall carbon demand.     

Zooplankton Composition and Trophic Status of Aquatic Species in the Laptev and East Siberian Seas

Oceanology - The species composition, abundance, biomass, and distribution of zooplankton were studied on the shelf and slope of the northwestern Laptev Sea and the shelf of the East Siberian Sea...     

北极拉普捷夫海夏、秋季颗粒有机碳的分布与来源

随着全球变暖的加剧,北极陆架边缘海碳的源汇过程对全球碳循环的影响及其气候环境效应日益显著。拉普捷夫海作为北冰洋典型的陆架边缘海,在大河、海冰、海洋初级生产力及海岸侵蚀的影响下,该区沉积有机碳的来源、输运和埋藏等过程独具特色。本文基于2018年中俄第二次北极联合科考获得的悬浮颗粒物样品和水文资料,研究了夏末秋初拉普捷夫海颗粒有机碳的分布特征、来源及其影响因素。结果表明,颗粒有机碳（POC）的浓度位于35.27～1 185.58 μg/L之间,平均为172.65 μg/L。受河流输入、海岸侵蚀和海洋初级生产力的影响,表层POC浓度分布呈现近岸高、远岸低趋势;底层POC浓度分布主要受控于沉积再悬浮作用,高浓度POC出现在勒拿河三角洲的东部区域。总悬浮颗粒物浓度与POC浓度总体呈显著正相关,显示出其对POC空间分布的直接影响,且两者在底层中的相关性要高于表层,表明不同层位的POC可能存在来源差异。研究区POC的δ¹³C值处于−31.03‰～−25.79‰之间,表层δ¹³C值较底层明显偏负,且部分站位的δ¹³C值甚至低于周边陆源有机碳的端元,这反映了可能除陆源输入的贡献外,近海浮游植物直接利用大量陆源有机质降解产生的溶解无机碳的过程也对该区域POC的供应和来源解析具有重要的影响。     

夏季南黄海总有机碳的分布特征及其影响因素

依据2006年7-8月对南黄海调查得到的总有机碳（TOC）数据,探讨了南黄海TOC的分布特征及其控制因素。结果表明：2006年夏季南黄海TOC质量浓度范围为0.91~2.53 mg/L,平均值为1.66 mg/L。北部近岸TOC质量浓度较高,呈现由近岸向外海递减的变化趋势;而南部近岸TOC值则较低,且分布趋势也与北部相反。在垂直方向上,表层TOC值最高,随着深度的增加而降低。TOC的分布趋势主要受控于水文结构,但在某些海流影响较小、生物量较大的海域,生物生产对TOC的含量也有一定的贡献。     

Process of Postglacial Transgression on the Coasts of the East Siberian and Laptev Seas

Oceanology - The width of shelves and continental slopes of the East Siberian and Laptev seas affected the postglacial transgression. This dependence, in turn, is directly determined by the...     

乳山近岸养殖区初级生产力时空分布及其与环境因子相关关系

于2017—2018年3月、5月、8月、10月在乳山海水增养殖海域进行了水文、气象、化学、浮游植物等要素的综合调查,文章分析了该海域初级生产力和主要环境因子间的相关关系并探讨了其相互影响。结果表明,2017—2018年调查区域水体初级生产力的波动范围为9.2～3 504.0mg/(m2·d)(以碳计),各年度均为8月最高,3月比5月、10月略高,5月和10月相当。3—5月乳山湾东汊和乳山东与文登交界处要高于其他区域,8月近岸外海整体较高,从近岸区到远岸初级生产力先逐渐增大后逐渐减小,10月的初级生产力普遍偏低。2018年3月和8月初级生产力与温度、pH值、无机氮、N/P值和盐度等相关环境因素有一定的显著相关关系,而在5月和10月相关关系则都不显著。此次调查结果能够反映出陆源输入、季节变化等生境改变对水体初级生产力的时空分布的影响。     

桑沟湾海域石油烃的分布特征及其与环境因子的相关性

2009-04-2010-02对山东荣成典型养殖海湾-桑沟湾海区表层海水的石油烃进行6个航次的监测,分析该海区石油烃的污染现状,探讨石油烃在桑沟湾表层海水中的分布特征,以及与水温、叶绿素a、营养盐等环境因子的相关性.结果表明,桑沟湾表层海水石油烃质量浓度的季节变化大致呈现春夏季高,秋季偏低,冬季最低的特点;水平分布基本...     

长江口北槽一期工程后滩槽沉积物分布特征及其影响因素

根据2000年7月和2001年5—6月份长江口北槽航道及两侧滩地进行的沉积物采样分析结果,对长江口深水航道一期工程实施后的滩槽泥沙交换情况以及在自然与工程双重影响下的沉积物分布情况进行了较为详细的讨论。长江口深水航道工程的实施,影响了长江口尤其是北槽及两侧滩地的水沙条件和沉积物分布。强劲的径流和潮流作用和风浪作用造成航槽及两侧滩地的冲淤转换及沉积物分布的变化;深水航道治理工程的实施使工程段内航槽泥沙粒径粗化,两侧滩地和工程段下游泥沙中值粒径变细,这反映了在工程实施后滩槽泥沙交换的变化。