北极拉普捷夫海春季冰藻和浮游植物群落结构及生物量分析

对1999年春季采集于北极拉普捷夫海东南部的冰藻和冰下浮游植物群落的种类组成进行了分析,并对丰度和生物量进行了统计和对比。藻种以硅藻占绝对优势,其中又以羽纹硅藻为主。优势种集中,主要包括海洋拟脆杆藻(Fragilariopsisoceanica)、圆柱拟脆杆藻(F.cylindrus)、寒冷菱形藻(Nitzschiafrigida)、普罗马勒菱形藻(N. promare)、带纹曲壳藻(Ach nanthestaeniata)、新寒冷菱形藻(Nitzschianeofrigida)、大洋舟形藻(Naviculapelagica)、范氏舟形藻(N. vanhoeffenii)、北极直链藻(Melosiraarctica)、北方舟形藻(N. septentrionalis)、新月细柱藻(Clindrothecaclosterium)和绿藻门的塔形藻(Pyramimonassp. )。微藻主要集中在冰底10cm,丰度为14. 6-1562. 2×104 cells·L-1,平均为639. 0×104 cells·L-1;生物量为7. 89-2093. 5μgC·L-1,平均为886. 9μgC·L-1,总体上比次冰底高1个数量级,比冰下表层水柱高2个数量级。冰底20cm冰柱的累计丰度和生物量平均分别为冰下20m水柱累计量的7. 7和12. 2倍,显示冰藻在春季海冰融化前在近岸生态系统中的重要作用。尽管各站位冰底和冰下表层水柱藻类群落的相似性普遍不高,但整个调查海域冰底和冰下水柱优势种极为相似,春季期间冰藻对冰下浮游植物群落的影响明显。由于     

南极中山站及毗邻地区湖泊与冰雪COD_(Mn)研究

在 CHINARE- 1 5考察期间对中山站及毗邻地区的湖泊和冰雪进行了采样。它们的CODMn指数与中国《地面水环境质量标准》相比 ,可分为三类 :一类水质所占比重最大 ,大约为56% ,二类和三类分别为 37%、7%。各类水体的 CODMn指数主要为自然源所贡献 ,人为污染不明显。湖水的 CODMn指数是生物生长状况、有机质含量、盐度和水体氧化还原程度的综合体现 ,新鲜降雪样的 CODMn指数指示了该地区的大气洁净度。     

南极中山站近岸海冰生态学研究Ⅲ.冰藻优势种的季节变化及其与冰下浮游植物的关系

自１９９２年４月１２日至１２月３０日对中山站以西内拉峡湾海冰和冰下水柱中藻类优势种组成和丰度进行了测定。４月份和１１月中旬至１２月中旬冰柱和水柱（０～５０ｍ）藻类丰度高达１０８～１０９ｃｅｌｓ／ｍ２。冰藻的普遍或季节性优势种主要包括Ａｍｐｈｉｐｒｏｒａｋｊｅｌｍａｎｉ、Ｂｅｒｋｅｌｅｙａｒｕｔｉｌａｎｓ、Ｎａｖｉｃｕｌａｇｌａｃｉｅｉ、Ｎｉｔｚｓｃｈｉａｂａｒｋｌｅｙｉ、Ｎ．ｃｙｌｉｎｄｒｕｓ、Ｎ．ｌｅｃｏｉｎｔｅｉ和Ｎｉｔｚｓｃｈｉａｓｐ．。由于藻类结合入冰后自身的演替，春－夏季海冰剖面中所记录的优势种组成并不能准确反映冰底优势种的季节演替过程。从冰底和水表藻种组成的对比表明，两者仅在春末冰底冰藻水华期间具有较强的相似性。秋、春季冰底冰藻水华的形成以现场生长为主，夏初冰藻释放入水后对冰下浮游植物的播种作用不明显。     

南极中山站近岸海冰生态学研究 Ⅱ．1992年冰下水柱浮游植物生物量的季节变化及其与环境因子的关系

自１９９２年４月１２日至１２月３０日对中山站附近内拉峡湾冰下水柱中浮游植物生物量以及环境因子的季节变化进行了测定。水中叶绿素ａ含量在０．０３－２１．４０ｍｇ／ｍ３之间波动，在覆冰期间，生物量基本上随深度的增加而下降；５－９月份各层次的生物量普遍低于０．５ｍｇ／ｍ３，８－９月份低于０．１ｍｇ／ｍ３。各层次中以水表含量的季节变化最为明显，成冰后在９月份形成低谷，于１２月中旬紧接着冰底水华的消失而形成单一峰值。生物量中微型浮游植物（＜２０μｍ）的比重在４－９月份的多数层次占有一半以上，１０月份后随着生物量的上升而下降，在水华期水表的比重最低，仅占总量的３．２％。其柱总生物量基本上与冰中生物量处于同一数量级，在冰藻水华期其量值甚至低于冰中生物量。营养盐（μｍｏｌ／Ｌ）的波动范围为ＰＯ４－Ｐ：０．３２－０．７９，ＳｉＯ３－Ｓｉ：２６．４７－６９．９２，ＮＯ３－Ｎ：１．４１－３１．７５，尽管水华期水表营养盐含量降至观测期间的最低点，但仍能满足冰下浮游植物的生长所需。光辐照度由于在冰水界面的量值仅为冰表入射光的不足５．３％至低于１％，成为水中产量最为可能的限制因子。     

Sea ice algae in the White and Barents seas: composition and origin

To examine algae populations, three expeditions (in March 2001, April 2002 and February 2003) were conducted in the Guba Chupa (Chupa Estuary; north-western White Sea), and one cruise was carried out in the open part of the White Sea in April 2003 and in the northern part of the Barents Sea in July 2001. Sea ice algae and phytoplankton composition and abundance and the content of sediment traps under the land-fast ice in the White Sea and annual and multi-year pack ice in the Barents Sea were investigated. The community in land-fast sea ice was dominated by pennate diatoms and its composition was more closely related to that of the underlying sediments than was the community of the pack ice, which was dominated by flagellates, dinoflagellates and centric diatoms. Algae were far more abundant in land-fast ice: motile benthic and ice-benthic species found favourable conditions in the ice. The pack ice community was more closely related to that of the surrounding water. It originated from plankton incorporation during sea ice formation and during seawater flood events. An additional source for ice colonization may be multi-year ice. Algae may be released from the ice during brine drainage or sea ice melting. Many sea ice algae developed spores before the ice melt. These algae were observed in the above-bottom sediment traps all year around. Three possible fates of ice algae can be distinguished: 1) suspension in the water column, 2) sinking to the bottom and 3) ingestion by herbivores in the ice, at the ice-water interface or in the water column.     

南极海冰区冰藻类群及兴衰过程

本文总结了国际上对南极冰藻类群及其生理生态特性的多年研究成果 ,结合我国科学家在南极长城站以及在戴维斯和中山站的越冬研究 ,阐述了南极海冰区的冰藻类群及其形成机理 ,对冰藻的形成、存活、旺发和消亡过程进行讨论 ,并对大洋浮冰区和近岸固定冰区冰藻类群的生态特性进行对比 ,提出了今后有待进一步深入研究的领域     

南极中山站近岸海冰生态学研究 Ⅳ.海冰营养盐浓度的季节变化及其与生物量的关系

对１９９２年４月至１２月间中山站近岸海冰营养盐状况以及与生物量的关系进行了分析。为了能与海水中的营养盐进行对比,对海冰融化样的营养盐数据进行了同期冰下海水表层盐度的校正。结果显示,海冰中多数层次的硝酸盐浓度低于冰下表层海水的浓度,而磷酸盐和硅酸盐浓度则正好相反,亚硝酸盐浓度在观测期间均高于冰下表层海水的浓度。海冰营养盐浓度无明显的变化规律,呈现较大的波动,它可以是冰下表层海水的数分之一直至高出一个数量级,除显著的冰底水华期外并不构成冰藻生长的限制因素。海冰营养盐的分布与叶绿素ａ含量无明显的相关性。     

加拿大海盆夏季冰区细菌和原生生物群落特性分析

采用表面荧光显微分析方法对2014年夏季中国第6次北极科学考察期间采集于加拿大海盆7个海冰站位的融池、冰芯和冰下海水样品进行了细菌和原生生物群落分析。结果表明,上述3类生境中的第一优势类群均为细菌(不包括ICE07站位出现水华融池的统计),分别占总生物量的42.8%、37.8%和50.7%;第二优势类群均为鞭毛虫,分别占总生物量的40.2%、34.3%和37.5%。包含细菌、鞭毛虫和纤毛虫在内的异养生物在总生物量中占有优势,显示微食物环在其中起着重要作用。在北冰洋夏季快速融冰的背景下,3类生境总体上缺少快速生长的条件,总生物量偏低。其中ICE07站位出现融池水华和冰表自养鞭毛藻高值,推测合适的藻种和营养盐的额外补充共同促成了该站位冰表(融池)藻华的形成。     

南极中山站近岸海冰生态学研究Ⅰ．1992年冰藻生物量的垂直分布及季节变化

从１９９２年４月至１２月对东南极中山站近岸当年冰生物量及其环境因子进行了观测。冰底有色层出现在４月下旬和１１月下旬，集中于冰底２～３ｃｍ，叶绿素ａ最高含量分别为８８．３ｍｇ／ｍ３和２８１０ｍｇ／ｍ３，相应的冰藻数量分别为３．５×１０６和１．２１×１０８个／升。柱总叶绿素ａ含量的季节性变化极为显著，尤其是以春季的大幅度快速增值为特征，变化范围为１．１７～５９．７ｍｇ／ｍ２，冰藻生物量主要分布在冰底，冬季期间则集中在冰底或冰的中上层。藻类优势种较为单一，秋季优势种为Ｎｉｔｚｓｃｈｉａｌｅｃｏｉｎｔｅｉ、Ｎ．ｂａｒｋｌｅｙｉ和Ｎ．ｃｙｌｉｎｄｒｕｓ；春季优势种为Ａｍｐｈｉｐｒｏｒａｋｊｅｌｍａｎｉ，Ｂｅｒｋｅｌｅｙａｒｕｔｉｌａｎｓ和Ｎ．ｌｅｃｏｉｎｔｅｉ。中山站近岸冰藻生物量的垂直分布和季节变化以及春季优势种的组成与东南极其它固冰区具有较强的相似性，与亚南极固冰区差异较大。     

Photosynthetic characteristics of sinking microalgae under the sea ice

The photosynthetic characteristics of sinking a microalgal community were studied to compare with the ice algal community in the sea ice and the phytoplankton community in the water column under the sea ice at the beginning of the light season in the first-year sea ice ecosystem on the Mackenzie Shelf, in the western Canadian Arctic. The phytoplankton community was collected using a water bottle, whereas the sinking algal community was collected using particle collectors, and the ice algal community was obtained by using an ice-core sampler from the bottom portion of ice core. Photosynthesis versus irradiance (P-E) incubation experiments were conducted on deck to obtain the initial slope (α^B) and the maximum photosynthetic rate (P_m^B) of the three algal communities. The α^B and the P_m^B of the light saturation curve, and chlorophyll a (Chl a) specific absorption coefficient (ā_ph*) between the sinking microalgal community and the ice algal community were similar and were distinctly different from the phytoplankton community. The significant linear relationship between α^B and P_m^B, which was obtained among the three groups, may suggest that a photo-acclimation strategy is common for all algal communities under the low light regime of the early season. Although the sinking algal community could be held for the entire duration of deployment at maximum, this community remained photosynthetically active once exposed to light. This response suggests that sinking algal communities can be the seed population, which results in a subsequent phytoplankton bloom under the sea ice or in a surface layer, as well as representing food for the higher trophic level consumers in the Arctic Ocean even before the receding of the sea ice.     

A coupled ice-ocean ecosystem model for 1-D and 3-D applications in the Bering and Chukchi Seas

Primary production in the Bering and Chukchi Seas is strongly influenced by the annual cycle of sea ice.Here pelagic and sea ice algal ecosystems coexist and interact with each other.Ecosystem modeling of sea ice associated phytoplankton blooms has been understudied compared to open water ecosystem model applications. This study introduces a general coupled ice-ocean ecosystem model with equations and parameters for 1-D and 3-D applications that is based on 1-D coupled ice-ocean ecosystem model development in the landfast ice in the Chukchi Sea and marginal ice zone of Bering Sea.The biological model includes both pelagic and sea ice algal habitats with 10 compartments:three phytoplankton(pelagic diatom,flagellates and ice algae:D,F,and Ai),three zooplankton(copepods,large zooplankton,and micro-zooplankton :ZS,ZL,ZP),three nutrients(nitrate+nitrite,ammonium,silicon: NO_3,NH_4,Si) and detritus(Det).The coupling of the biological models with physical ocean models is straightforward with just the addition of the advection and diffusion terms to the ecosystem model.The coupling with a multi-category sea ice model requires the same calculation of the sea ice ecosystem model in each ice thickness category and the redistribution between categories caused by both dynamic and thermodynamic forcing as in the physical model.Phytoplankton and ice algal self-shading effect is the sole feedback from the ecosystem model to the physical model.     

北冰洋中心区表层海水营养盐水平及浮游植物群落对快速融冰的响应

本文依托2010夏季中国第四次北极科学考察,通过对高纬度极地冰下水和冰芯的营养盐的连续观测及表层水颗粒物的藻类色素分析,获取了夏季快速融冰下冰水界面营养盐和光合色素的分布信息。结果表明调查期间表层水磷酸盐和硅酸盐相对于无机氮更丰富（依据Redfield比值）,表现为显著的氮限制。而冰芯无机氮浓度相对更高,融冰释放对水体无机氮有一定的补充。色素分析显示岩藻黄素（Fuco）和叶绿素a（Chl a）是水体颗粒物的主要光合色素。在8/15至8/18期间,叶绿素c（Chl c）、硅藻黄素（Diato）、硅甲藻黄素（Diadino）和岩藻黄素（Fuco）分别达到6,22,73和922μg/m3,体现了硅藻在群落中的优势地位。岩藻黄素（Fuco）的浓度在融冰快速期间有巨大的提升,主要来源于冰芯底部释放的衰老的冰生硅藻和浮游硅藻的生长。此外,青绿黄素（Prasino）和叶黄素（Lut）与岩藻黄素（Fuco）分布模式有明显的差异,暗示青绿藻和绿藻与硅藻对海冰融化的不同响应。     

Ice algae in the Barents Sea: types of assemblages, origin, fate and role in the ice-edge phytoplankton bloom

Ice algal accumulations were recognised by their vertical distribution in the ice, as surface, interior and bottom assemblages. The latter were quantitatively the most important in the Barents Sea and in particular the sub-ice assemblage floating towards, or attached to, the undcr-surface of the sea ice. Colonisation of the ice takes place by a "sieving" of the water between closely spaced platelets on the ice under-surface. Once associated with the ice, the assemblage undergoes a succession terminated by the dominance of ice specialists. In a horizontal S-N section through the ice, three distinct zones may be recognised: at the ice edge the recently colonised ice has a layer of algae up to a few millimeters in thickness consisting primarily of planktonic species. Further into older first year ice the algal layer becomes thicker and is typically dominated by the pennate diatom Nilzschia frigida Grunow. Below multi-year ice in the central polar basin decimetre-thick mats of algae are found, consisting almost exclusively of the centric diatom Melosira arclica (Ehrenberg) Dickie and a few associated, mostly epiphytic, species. The predominantly planktonic sub-ice assemblages at the ice edge can grow under stable conditions as soon as the light becomes adequate in the spring, and they are able to multiply actively for one to two months before planktonic growth is possible. The sub-ice plankton assemblage thus forms an inoculum released to the stabilising water when the ice starts melting. This may explain how a phytoplankton bloom can develop explosively at the ice edge as soon as the ice melting commences, at a time when the number of algal cells in the water column is still very low.     

Phytoplankton in the south-western Kara Sea: composition and distribution

The taxonomic composition and spatial distribution of pelagic algae were studied in the south-western Kara Sea in August-September 1981. In the north-western and easternmost regions of the study area the phytoplankton community, dominated by neritic diatoms and autotrophic dinoflagellates, was at the late spring bloom stage of the seasonal succession. In the central deep-water zone of the sea, there was a predominance of heterotrophic dinoflagellates from the genera Protoperidinium and Dinophysis , and the autotrophic compartment of the algal community was clearly in a stage of decline. The distribution of the phytoplankton assemblages followed closely the major routes of receding marginal ice zones. Three stages of the seasonal succession were established for the area of interest: (1) early spring (ice edge) bloom of arcto-boreal neritic diatoms; (2) late spring bloom of neritic diatoms and autotrophic dinoflagellates, fuelled by continental run-off; and (3) summer minimum with a predominance of heterotrophic dinoflagellates, followed by autumnal decline of the phytoplankton community.     

Phototrophic and heterotrophic nano- and microorganisms of sea ice and sub-ice water in Guba Chupa (Chupa Inlet), White Sea, in April 2002

Autotrophic and heterotrophic flagellates, microalgae and ciliates sampled at four stations in the White Sea in April 2002 were studied using epifluorescence microscopy. The concentrations of phototrophic 1.5 μm algae in the middle and lower part of the ice core were very high: up to 6.1 ± 10⁸ cells I⁻¹ and 194 μg C I⁻¹. Heterotrophic algae made up the largest proportion of the nanoplankton (2-20 μm) and microplankton (20-200 μm) at depths 10-25 m below the ice. The proportion of ciliates ranged from about 0.01% to 18% at different stations and depths. Most of the ciliate biomass in the ice was made up of typical littoral zone species, whereas the water under the ice was dominated by phototrophic Myrionecta rubra . Ice algae, mainly flagellates in the upper ice layer and diatoms in the bottom ice layer, supported the proliferation of heterotrophs, algae and ciliates in early spring. Small heterotrophs and diatoms from the ice may provide food for early growth and development of pelagic copepods. Mass development of the ice algae in early spring appears typical for the seasonal ice of the White Sea. Ice algae differ in species composition from the spring pelagic community and develop independently in time and space from the spring phytoplankton bloom.     

楚科奇海和白令海浮游植物的种类组成与分布

根据 1 999年 7月至 8月我国首次北极科学考察期间“雪龙”号考察船在楚科奇海 ( 66°0 .3′N75°1 8.6′N ,1 5 3°36.5′W 1 74°5 9.5′W )和白令海 ( 5 5°5 9.8′N66°0 .3′N ,1 73°2 1 .1′E1 75°5 3.9′W)采集的 5 1份网采样品和 2 4份水采样品 ,鉴定浮游植物 3个门类 38属 1 2 1种 (含变种和变型 ) ,都是真核藻类。其中楚科奇海有 33属 1 0 3种 ,白令海有 2 5属 71种 ,两海区共有种 49种。这些种类可分为 4个生态类群 :( 1 )北极类群 ;( 2 )北极、亚北极北方类群 ;( 3)北方温带类群 ;( 4 )世界性广温类群等。主要优势种有楚科奇海的格鲁菱形藻 (Nitzschiagrunowii)、诺登海链藻(Thalassiosiranordenskioldi)和聚生角毛藻 (Chaetocerossocialis)等和白令海的西氏细齿状藻(Denticulaseminae)、柔弱菱形藻 (Nitzschiadilicatissima)、成列菱形藻 (N .seriata)和长海毛藻(Thalassiothrixlongissima)等。楚克奇海浮游植物的平均丰度 ( 8.32× 1 0 7个 /m3)远高于白令海( 1 .5 8× 1 0 6个 /m3)。文中还讨论了调查区浮游植物的分布特点及其与环境的关系。     

Temporal variations in the abundance and sinking flux of diatoms under fast ice in summer near Syowa Station, East Antarctica

To investigate the fate of ice algae released from sea ice, we investigated the abundance, species composition, and sinking flux of diatoms in the water column under fast ice near Syowa Station, Antarctica during the summer of 2005/2006. The diatom assemblage in the water column consisted of chain-forming planktonic species, in contrast to the under-ice assemblage dominated by pennate species reported from this site in the past; this dissimilarity suggests the presence of an unconsolidated platelet ice layer under the congelation ice, within which planktonic species can bloom. Among the dominant diatoms, Porosira pseudodenticulata and Pseudo-nitzschia cf. turgiduloides were dominant in the water column, and their water column stocks were higher than their mass sedimentation. These species apparently maintain their populations in the surface layer, as their production remains in the water column. In contrast, Fragilariopsis kerguelensis and Thalassiosira australis were scarce in the water column but rich in the flux, indicating active sinking and export of their production to the benthic ecosystem. This distinction in buoyancy control and sinking characteristics of the dominant diatoms on release from the fast ice influences the diatom species composition and carbon flow under the ice.     

Spatial variability of phytoplankton, nutrients and new production estimates in the waters around Svalbard

Phytoplankton dynamics and carbon input into Arctic and sub-Arctic ecosystems were investigated around Svalbard, in summer 1991. Phytoplankton biomass, species composition and dissolved nutrient concentrations were analysed from water samples collected along seven transects. Phytoplankton biomass was low especially to the north (Chlorophyll-a mean 0.3 pg 1- '), where flagellates dominated the communities and only ice-diatoms were present. To the west, the phytoplankton composition was representative of a summer Atlantic community, in a post-bloom state. Zooplankton grazing, mainly by copepods, appeared to be the main control on biomass to the west and north of Svalbard.
In the Barents Sea (east of Svalbard), an ice edge bloom was observed (Chlorophyll-a max. 6.8 pgl-') and the ice edge receded at a rate of approximately 1 1 km day-'. The phytoplankton community was represented by marginal ice species, especially Phaeocystis poucherii and Chaeroceros socialis. South of the ice edge, Deep Chlorophyll Maxima (DCM) were observed, as surface waters became progressively nutrient-depleted. In these surface waters, the phytoplankton were predominantly auto- and heterotrophic flagellates.
Carbon production measurements revealed high net production (new and regenerated) to the north of the Barents Sea Polar Front (BSPF); it was especially high at the receding ice edge (reaching 1.44gC m-'day-'). To the south, a low level of production was maintained, mainly through regenerative processes.     

楚科奇海浮冰区夏季短期颗粒有机物通量及其主要组分

中国首次北极科学考察期间 ,于 8月 2 0- 2 3日在楚科奇海浮冰区联合冰站实施了为期 4天的短期颗粒有机物通量研究。结果显示真光层的颗粒有机碳通量为 1 .582mgCm- 2 day- 1 ,2 2 0m深层为 1 .339mgCm- 2 day- 1 ,而相应的沉降颗粒物总通量分别高达 8.788和 1 0 .30 3mgm- 2 day- 1 。显示北极浮冰区的夏季融冰季节后期 ,颗粒有机碳通量的水平较低。与颗粒有机碳通量水平相似 ,生源硅和活性磷的通量水平也较低。对硅藻通量组份的分析表明 ,真光层沉降硅藻的优势种为Nitzschiacf.seriata、Naviculaglacialis和Melosirasp .,而 2 2 0m层则Lepto cylindrussp .占绝对优势 ,其丰度数量百分比均超过 70 %。硅藻碳通量的绝对值较低 ,为0 .1 0 7- 0 .1 1 3mgCm- 2 day- 1 。然而 ,真光层大型桡足类的碳估算值高达 1 0 8.67mgCm- 2day- 1 ,占浮游动物总碳量的 95 .3 % ,大型浮游动物的表观碳通量高于浮游植物碳通量 2- 3个数量级 ,显示楚科奇海夏季融冰期高浮游动物碳量、低浮游植物碳量的特点。但浮游动物表观碳量高的主要原因与浮游动物的昼夜垂直运动有关 ,却并非是实际向深层海洋传输的碳量     

1988／1989年夏季南极长城海湾生态环境观测

自１９８８年１１月至１９８９年３月，对南极长城湾（６２°１３′Ｓ，５８°５７′Ｗ）中５个站位的水温、ｐＨ值、海水透明度、水下照度、水中和海冰中叶绿素含量、磷酸盐含量、亚硝酸盐和硝酸盐含量等理化要素，每月进行１至２次不定期的常规测定。在整个调查期间，海水温度变化范围在－１．６～２．２°Ｃ之间，ｐＨ值变化范围在８．０～９．１之间，海水中叶绿素ａ的变化范围在０．３０～１．４８ｍｇ／ｍ３之间，叶绿素ａ的最大值出现在１１月２６日５号站的表层水中，海冰中叶绿素ａ的含量远远高于海水中的含量，海冰中叶绿素ａ的变化范围在２．５５～５６．８４ｍｇ／ｍ３之间。磷酸盐含量变化范围在１．０２３～２．１８７μｇＰ／Ｌ，亚硝酸盐含量变化范围在０．０９３～０．１８６μｇＮ／Ｌ之间，硝酸盐含量变化范围在１３．３０８～２６．５８４μｇＮ／Ｌ之间。本文对以上结果作了初步探讨