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1.
黄海和东海是西北太平洋重要的边缘海,复杂的海洋环流和丰富的陆源物质输入共同影响着海域环境和生态系统。为了解黄、东海浮游植物群落组成、分布状况及其影响因素,本研究于2015年8—9月期间,通过流式细胞仪和形态学观察等方法,调查了该海域微型真核藻类、微微型真核藻类、聚球藻（Synechococcus）、原绿球藻（Prochlorococcus）以及浮游植物优势种的组成、丰度与分布情况,并基于浮游植物种类和丰度状况进行了聚类分析。结果表明,黄、东海浮游植物群落组成存在明显差别,黄海海域微型浮游植物丰度高于东海,而微微型浮游植物丰度低于东海,原绿球藻主要分布在东海海域。黄、东海海域浮游植物群落组成及分布状况与海域环境特征密切相关。夏季黄海海域相对封闭,受黄海冷水团控制,表层海水中高丰度的微型真核藻类主要出现在冷水团西侧边缘锋面区。东海海域受到长江冲淡水和黑潮水向岸入侵的强烈影响,在长江口邻近海域出现硅藻赤潮,而原绿球藻呈现出自外海向近岸输送的分布态势。相关结果可望为进一步探讨陆源物质输入和邻近大洋对我国近海生态系统的影响及机理提供依据。 相似文献
2.
以宏基因组技术探讨渤海秋冬季节病毒多样性 总被引：1，自引：0，他引：1
为研究渤海海域病毒群落总体状况,本文以渤海的B47站表层海水为代表,对两个时间点(2010年9月,2011年12月)的病毒宏基因组做出全面分析。采集海水样品后过滤并经过切相流系统浓缩,提取DNA测序,再进行生物信息学分析,包括病毒组的种群分类、功能基因分析、系统进化分析等。分析结果指明,这两个时间点的病毒群落均由双链DNA病毒(97.75%,scaffold百分比)占据优势地位,其中尤以有尾噬菌体(80.86%,scaffold百分比)居多。按宿主区分,最大的一类病毒为聚球藻噬藻体(10.29%,scaffold百分比)。渤海病毒群落最为丰富的功能基因为复制、结合和修复基因,且冬季(33.77%,ORF百分比)大于秋季(16.39%,ORF百分比)。结果表明:在渤海病毒组中,(1)存在理论上只出现在亚热带海域的原绿球藻噬藻体;(2)物种组成、物种多样性、功能基因比例呈现季节变化;(3)相比远洋病毒组有一定独特性;(4)可能存在未知的T4-like病毒分支。 相似文献
3.
4.
Picoplankton community structure on the Atlantic Meridional Transect: a comparison between seasons 总被引：3，自引：0，他引：3
Mikhail V. Zubkov Michael A. Sleigh Peter H. Burkill Raymond J. G. Leakey 《Progress in Oceanography》2000,45(3-4)
Samples collected from 10 depths at 25 stations in September–October 1996 and 12 depths at 28 stations in April–May 1997 on an Atlantic Meridional Transect between the British Isles and the Falkland Islands were analysed by flow cytometry to determine the numbers and biomass of four categories of picoplankton: Prochlorococcus spp, Synechococcus spp, picoeukaryotic phytoplankton and heterotrophic bacteria. The composition of the picoplankton communities confirmed earlier findings (Zubkov, Sleigh, Tarran, Burkill & Leakey, 1998) about distinctive regions along the transect and indicated that the stations should be grouped into five provinces: northern temperate, northern Atlantic gyre, equatorial, southern Atlantic gyre and southern temperate, with an intrusion of upwelling water off the coast of Mauritania between the northern Atlantic gyre and equatorial waters. Prochlorococcus was the most numerous phototrophic organism in waters of both northern and southern gyres and in the equatorial region, at concentrations in excess of 0.1×106ml−1; it also dominated plant biomass in the gyres, but the biomass of the larger picoeukaryotic algae equalled that of Prochlorococcus in the equatorial region; higher standing stocks of both Prochlorococcus and picoeukaryotes were present in spring than in autumn in waters of both gyres. In temperate waters at both ends of the transect the numbers and biomass of picoeukaryotes and, more locally, of Synechococcus increased, and the Synechococcus, particularly, were more numerous in spring than in autumn. There was a pronounced southward shift of the main populations of both Synechococcus and Prochlorococcus in April–May in comparison to those of September–October, associated with seasonal changes in solar radiation, the abundance of Prochlorococcus dropping sharply near the 17°C contour, while Synechococcus was still present at temperatures below 10°C. Picoeukaryotes were more tolerant of low temperatures and lower light levels, often being more abundant in samples from greater depths, where they contributed to the deep chlorophyll maximum. Heterotrophic bacterial numbers and biomass tended to be highest in those samples where phototrophic biomass was greatest, with peaks in temperate and equatorial waters, which were shifted southwards in April–May compared with September–October. 相似文献
5.
During Nov. 2006 and Feb. 2007, two investigations were carried out to investigate the abundance, carbon biomass, and distribution
of picoplankton (Pico) and its relationship to the hydrological regime in the East China Sea (ECS). Pico consisted of three
groups of photosynthetic picoplankton (phPico)—Synechococcus (Syn), Prochlorococcus (Pro) and Picoeukaryotes (PEuk)—and heterotrophic bacteria (HBAC). The average abundance of Pro, PEuk and HBAC was lower
in autumn than in winter, but for Syn the opposite trend was observed. Water temperature, salinity, and stability of water
column influenced Pico distribution in both seasons. Regression analysis showed distinct positive correlations between HBAC
and phPico in both seasons. Syn contributed more to phPico in coastal waters, whereas Pro dominanted in the shelf and slope
areas. PEuk was the major contributor to carbon biomass. In the Pico community, HBAC was predominant, both in abundance and
in terms of carbon biomass. The phenomenon of subsurface chlorophyll maximum (SCM) was observed ubiquitously in the shelf
and slope area, and Pico organisms were the major contributors. 相似文献
6.
An-Yi Tsai Gwo-Ching Gong Robert W. Sanders Chien-Fu Chao Kuo-Ping Chiang 《Journal of Oceanography》2010,66(6):873-883
This two-year study investigates the possible factors that determine spatial and temporal dynamics of picoplankton (heterotrophic
bacteria, autotrophic picoplankton—Synechococcus spp., Prochlorococcus, and picoeukaryotes) and nanoflagellate abundance in the subtropical Ilan Bay, Taiwan, where the inner bay is affected by
freshwater run-off from the Lanyang River and the eastern outer bay by the Kuroshio Current. In the inner bay, there was more
rain and freshwater discharge in 2005 than in 2004 during the warm season (>24° C, June–September). The abundance of bacteria,
Synechococcus spp., Prochlorococcus, and picoeukaryotes and the percentage contributions of pigmented nanoflagellate (PNF %) were two- to eight-fold greater
during this period (July in 2005) than for other sampling periods. Relatively low abundance of heterotrophic nanoflagellates
(HNF) in the presence of abundant picoplankton prey suggests that top-down control determined HNF abundance in the Ilan Bay,
Taiwan. 相似文献
7.
《Deep Sea Research Part I: Oceanographic Research Papers》2006,53(11):1845-1863
Chlorophyll and carotenoid pigments were measured at stations in the Bismarck Sea north of Papua New Guinea and along the equator between 143°E and 152°E as part of the Tropical River Ocean Processes In Coastal Settings (TROPICS) programme in August 1997 and January/February 2000. Algal class abundances were estimated from these pigments using the CHEMTAX programme. The algal classes likely to be present (based on microscopy, HPLC chromatograms, literature and unpublished data from the region) and estimated by CHEMTAX were diatoms, cryptophytes, chlorophytes, haptophytes, chrysophytes, Synechococcus and Prochlorococcus. The first period corresponded to the SE tradewind season, when there was a drought in Papua New Guinea and the discharge from the Sepik River was unusually low. Samples were collected on four N–S transects (approximately 150 km in length): one to the east of the Sepik River, one from the mouth of the Sepik River and two to the west of the Sepik River. Stations in the central Bismarck Sea and along the equator were characterised by a deep chlorophyll maximum (DCM), and haptophytes and Prochlorococcus were the major algal classes. Stations affected by the Sepik River plume were characterised by a more homogeneous distribution of chlorophyll with chlorophytes making a significant contribution, particularly at shallower depths. Synechococcus and chrysophytes were moderately abundant, while cryptophytes and diatoms were of minor importance. The second cruise occurred during the NW monsoon under conditions of high river flow, and samples were collected along a transect from the mouth of the Sepik River to Manus Island and in the central Bismarck Sea. Chlorophyll concentrations were higher than in 1997, particularly in near surface waters, while a DCM was generally not observed at any station in the Bismarck Sea—even at stations upstream (and upwind) and far removed from the mouth of the Sepik River. Prochlorococcus made a smaller, and chlorophytes a larger, contribution to chlorophyll than in 1997. Unlike the situation in 1997, there were large station to station variations in the vertical profiles of chlorophyll and algal class distributions which cannot be attributed directly to the plume from the Sepik River. Pigment ratios, fitted by the CHEMTAX programme, were generally in good agreement with literature values. 相似文献
8.
RG Barlow T Lamont M-J Gibberd M van den Berg K Britz 《African Journal of Marine Science》2015,37(4):467-484
Phytoplankton community structure was elucidated during summer and winter in the KwaZulu-Natal Bight using pigment and CHEMTAX analyses. The surface pattern in January 2010 indicated that diatoms, haptophytes and prasinophytes tended to be the most prominent groups inshore and in the southern sector of the bight, whereas Prochlorococcus and Synechococcus were more dominant in the north and towards the offshore region. At the deep chlorophyll maximum (DCM), diatoms were dominant in the inner bight and in the south, with prasinophytes being the prominent flagellates, but this changed to Prochlorococcus and pelagophytes being the important groups in the northern sector and outer part of the bight. A different pattern was observed at the surface in July 2010, where diatoms, haptophytes, prasinophytes and cryptophytes in varying proportions comprised most of the community in the inner half of the bight, whereas Synechococcus and haptophytes were the main groups in the outer sector. A similar pattern occurred at the DCM, except that Synechococcus was less prominent and pelagophytes were distributed across the bight in both the inshore and offshore zones. Observations and relationships between phytoplankton groups and environmental parameters indicated that the groups were most closely related to temperature, accounting for 24–64% of the deviance. The influence of nutrients on phytoplankton was less clear but nitrate and silicate seemed to account for some of the patchy distribution patterns. 相似文献
9.
Seasonal appearance ofProchlorococcus was studied by flow cytometry in Suruga Bay, Japan in 1992–1993.Prochlorococcus cells were in high concentrations (>1×104 cells ml–1) from July to October 1992 and September 1993, when the water temperature was over 20°C. The 16S rRNA of the isolated cells showed 98.5% sequence homology with that ofP. marinus (Sargasso strain), indicating that they are the same species. The former has a high divinyl-chlorophyll (DV-Chl.)a/b ratio similar to the Mediterranean strain and different from the Sargasso strain. Maximum concentration ofProchlorococcus at the surface water was 2.5×104 cells ml–1 in August 1992 and their DV-Chl.a accounted for 4.0% of the total chlorophylla. A decrease in cell density to less than 5×103 cells ml–1 was observed from December to May with an exceptional rise in January 1993. WhileProchlorococcus showed a maximum concentration of 3.6×104 cells ml–1 at 10 m depth in September 1992, phycoerythrin (PE)-richSynechococcus spp. were dominant with their maximum concentration of 2.2×105 cells ml–1 in the same water body. On the other hand, phycocyanin (PC)-richSynechococcus spp. and the larger phytoplankters showed maximum concentrations in the surface waters in May and June. BothProchlorococcus and PE-richSynechococcus showed their lowest concentrations in April. A significant positive correlation was obtained between cell concentrations of the PE-richSynechococcus andProchlorococcus. 相似文献
10.
为全面了解黄海典型海区微微型浮游植物的季节变化特征,于2009年7月至2010年6月在北黄海獐子岛海域和2010年1~12月在南黄海胶州湾进行逐月调查采样,利用流式细胞仪检测了表层海水中微微型浮游植物(picophytoplankton)的丰度,包括聚球藻(Synechococcus,SYN)和微微型真核浮游植物(picoeukaryotes,PEUK),并分析了其与环境因子的关系。獐子岛海域和胶州湾SYN和PEUK全年广泛分布,獐子岛海域SYN丰度范围在0.05×103~120.00×103cells/mL之间,丰度在秋季最高;胶州湾SYN丰度范围在0.02×103~61.80×103cells/mL之间,丰度在夏季最高。獐子岛海域PEUK丰度范围在0.01×103~18.76×103cells/mL之间,丰度在秋季最高;胶州湾PEUK丰度范围在0.25×103~95.57×103 cells/mL之间,丰度在春季最高。獐子岛海域微微型浮游植物丰度组成以SYN为主;而胶州湾以PEUK为主。PEUK是两海区微微型浮游植物生物量的主要贡献者。相关性分析结果表明,温度是影响两海区SYN丰度季节变化的最主要因素;影响PEUK季节分布的因素不完全一致,獐子岛海域PEUK丰度主要受温度调控;胶州湾PEUK丰度主要受温度和营养盐浓度影响。与已有研究比较,这两个海区的微微型浮游植物生物量对浮游植物生物量的贡献明显高于其他温带沿岸海域,预示微微型浮游植物在獐子岛海域和胶州湾生态系统中的重要作用,值得进一步深入研究。 相似文献
11.
菲律宾海三种微微型浮游生物颗粒丰度及其光散射作用 总被引：1，自引：0，他引：1
2004年秋季在菲律宾海取得了微微型生物颗粒样品和光衰减剖面资料,然后对三种常见的微微型颗粒(原绿球藻,聚球藻和自养真核细胞)丰度及其光学性质做了初步分析和估算。研究结果表明,菲律宾海原绿球藻的丰度最高,其次为聚球藻,自养真核细胞的丰度最低。3种微微型颗粒的光散射系数同水体剖面的光衰减系数(cp)具有明显的相关关系。3种微微型颗粒的散射作用仅占总光衰减系数的5.1%,其中原绿球藻、自养真核细胞和聚球藻分别占2.6%,2.2%和0.3%。 相似文献
12.
T. Šilović Z. Ljubešić H. Mihanović G. Olujić S. Terzić Ž. Jakšić D. Viličić 《Estuarine, Coastal and Shelf Science》2011
Picoplankton distribution at the boundary zone of the southern Adriatic in May 2009 on a 75 km long shelf-continental slope transect was assessed by combining epifluorescence microscopy, flow cytometry and high-performance liquid chromatography data with hydrographic observations. The picoplankton distribution was greatly influenced by the hydrographic conditions prevailing in the southern Adriatic because of the influence of the Levantine Intermediate Water (LIW) and East Adriatic Current (EAC) forcing. Heterotrophic bacteria numerically dominated the picoplankton community through the entire transect with no significant accumulation. By contrast, picophytoplankton accumulated in the 50–75 m layer, forming a pronounced deep chlorophyll maximum. Synechococcus dominated the photosynthetic picoplankton, whereas picoeukaryotes were the least abundant. The intrusion of warm LIW observed in the layer between 100 and 350 m was followed by Prochlorococcus and Synechococcus peaks (10 × 103 cells mL−1 and 90 × 103 cells mL−1, respectively), as well as by the appearance of two Synechococcus ecotypes. Most picoeukaryotes were observed at the offshore stations, where geostrophic current calculation revealed the strongest EAC influence. A strong EAC spread over the central and eastern basin created a barrier for Prochlorococcus, whereas the picoeukaryote maxima coincided with the core of the EAC, suggesting its persistence to hydrological instabilities. 相似文献
13.
Molecular diversity of phytoplankton in the East China Sea around Jeju Island (Korea), unraveled by pyrosequencing 总被引：1，自引：0，他引：1
Daphne Georgina Faria Man-Duck Lee Joon-Baek Lee Juyun Lee Man Chang Seok Hyun Youn Young Sang Suh Jang-Seu Ki 《Journal of Oceanography》2014,70(1):11-23
The East China Sea (ECS) around Jeju Island lies in a transitional region between the temperate and subtropical zones and is influenced by the Kuroshio Current. Hence, this area has been considered an important monitoring site for oceanic ecosystem changes. Herein, we assessed the community structure and diversity of the phytoplankton in the ECS around Jeju Island using small subunit ribosomal RNA pyrosequencing. We analyzed eight samples collected from the surface and at 30 m- and/or 50-m depths from two neritic and oceanic stations each from 24–30 April 2011. Comparisons of 15,498 pyrosequences identified 172 phylotypes of phytoplankton, excluding cyanobacteria, from the four surface stations. These pyrosequences were represented by dinoflagellates (29 %), stramenopiles (31 %), and chlorophytes (>39 %), with minor contributions from cryptophytes, haptophytes, and Telonemia. Phylotypes retrieved at 30- and 50-m depths were very similar to the surface samples. However, phylotype diversity and community structure varied considerably with the stations. Dominant phylotypes included Karlodinium veneficum, Ostreococcus tauri, Skeletonema marinoi, and Thalassiosira curviseriata, and many of the detected phylotypes include new records for the present study area. This study provides a valuable phylotype reference for future phytoplankton community structure and diversity studies with regard to marine environmental changes. 相似文献
14.
《Deep Sea Research Part I: Oceanographic Research Papers》2001,48(1):297-314
Abundance distribution and cellular characteristics of picophytoplankton were studied in two distinct regions of the equatorial Pacific: the western warm pool (0°, 167°E), where oligotrophic conditions prevail, and the equatorial upwelling at 150°W characterized by high-nutrient low-chlorophyll (HNLC) conditions. The study was done in September–October 1994 during abnormally warm conditions. Populations of Prochlorococcus, orange fluorescing Synechococcus and picoeukaryotes were enumerated by flow cytometry. Pigment concentrations were studied by spectrofluorometry. In the warm pool, Prochlorococcus were clearly the dominant organisms in terms of cell abundance, estimated carbon biomass and measured pigment concentration. Integrated concentrations of Prochlorococcus, Synechococcus and picoeukaryotes were 1.5×1013, 1.3×1011 and 1.5×1011 cells m−2, respectively. Integrated estimated carbon biomass of picophytoplankton was 1 g m−2, and the respective contributions of each group to the biomass were 69, 3 and 28%. In the HNLC waters, Prochlorococcus cells were slightly less numerous than in the warm pool, whereas the other groups were several times more abundant (from 3 to 5 times). Abundance of Prochlorococcus, Synechococcus and picoeukaryotes were 1.2×1013, 6.2×1011 and 5.1×1011 cells m−2, respectively. The integrated biomass was 1.9 g C m−2. Prochlorococcus was again the dominant group in terms of abundance and biomass (chlorophyll, carbon); the respective contributions of each group to the carbon biomass were 58, 7 and 35%. In the warm pool the total chlorophyll biomass was 28 mg m−2, 57% of which was divinyl chlorophyll a. In the HNLC waters, the total chlorophyll biomass was 38 mg m−2, 44% of which was divinyl chlorophyll a. Estimates of Prochlorococcus, Synechococcus and picoeukaryotes cell size were made in both hydrological conditions. 相似文献
15.
Ralf Goericke Nicholas A. Welschmeyer 《Deep Sea Research Part I: Oceanographic Research Papers》1993,40(11-12)
The newly-discovered prochlorophyte Prochlorococcus marinus is often numerically dominant in the euphotic zone of the tropical and subtropical ocean; however, its contribution to phytoplankton biomass and primary production is largely unknown. Using its unique pigment divinyl-chlorophyll a (Chl a2) as a chemosystematic marker, we show that Prochlorococcus is present at a station in the Sargasso Sea throughout most of the year. Whereas it is only found at depth during the early summer, it can be found throughout the euphotic zone during the rest of the year. Averaged over the year Prochlorococcus pigment-biomass constitutes about 30% of the total. Its growth rate, estimated from the incorporation of 14C into Chl a2 ranged from values of 0.3 day−1 in the surface layer to values less than 0.1 day−1 at the bottom of the euphotic zone. Averaged over the seasons, approximately 25% of the total productivity was due to Prochlorococcus. Prochlorococcus clearly is an important component of the ecosystem in the Sargasso Sea, and perhaps the world ocean. 相似文献
16.
Role of environment and hydrography in determining the picoplankton community structure of Sagami Bay,Japan 总被引：1，自引：0，他引：1
Smita Mitbavkar Toshiro Saino Naho Horimoto Jota Kanda Takashi Ishimaru 《Journal of Oceanography》2009,65(2):195-208
Seasonal variations in the picoplankton community were investigated from June 2002 to March 2004 within the photic zone of
Sagami Bay, Japan. The study area was mostly dominated by coastal waters during the warm period (mixed layer water temperature
≥ 18°C). During the cold period (mixed layer water temperature ≤ 18°C), the water mass was characterized by low temperature
and high saline waters indicative of the North Pacific Subtropical Mode Water (NPSTMW). Occasionally, a third type of water
mass characterized by high temperature and low saline properties was observed, which could be evidence of the intrusion of
warm Kuroshio waters. Synechococcus was the dominant picophytoplankton (5−28 × 1011 cells m−2) followed by Prochlorococcus (1−5 × 1011 cells m−2) and picoeukaryotes during the warm period. Heterotrophic bacteria dominated the picoplankton community throughout the year,
especially in the warm period. During the Kuroshio Current advection, cyanobacterial abundance was high whereas that of picoeukaryotes
and heterotrophic bacteria was low. During the cold period, homogeneously distributed, lower picophytoplankton cell densities
were observed. The dominance of Synechococcus in the warm period reflects the importance of high temperature, low salinity and high Photosynthetically Active Radiation
(PAR) on its distribution. Cyanobacterial and heterotrophic bacterial abundance showed a positive correlation with temperature.
Prochlorococcus and picoeukaryotes showed a positive correlation with nutrients. Picoeukaryotes were the major contributors to the picophytoplankton
carbon biomass. The annual picophytoplankton contribution to the photosynthetic biomass was 32 ± 4%. These observations suggest
that the environmental conditions, combined with the seasonal variability in the source of the water mass, determines the
community structure of picoplankton, which contributes substantially to the phytoplankton biomass and can play a very important
role in the food web dynamics of Sagami Bay. 相似文献
17.
Miho Hirose Toshiya Katano Yuichi Hayami Atsushi Kaneda Takeshi Kohama Hidetaka Takeoka Shin-ichi Nakano 《Estuarine, Coastal and Shelf Science》2008
The Bungo Channel in southwestern Japan receives both warm, called Kyucho, and cold deep-water intrusions (bottom intrusion) from the Pacific Ocean. Abundances of Prochlorococcus, Synechococcus, and eukaryotic picophytoplankton were monitored from 18 July to 17 August 2001 to clarify whether advected picophytoplankton from the Pacific Ocean can grow in the channel or not. Synechococcus cells were further discriminated into low- and high-PUB types according to their fluorescence property in flow cytometry. From 18 to 25 July, the water temperature decreased by 3 °C at a 5-m depth at all stations, indicating the occurrence of a bottom intrusion. From 25 July to 4 August, a Kyucho occurred and the water temperature rapidly increased. From 4 to 17 August, a bottom intrusion and a Kyucho both occurred twice, although the intensities were smaller than those occurring until 4 August. From 18 to 30 July, the abundance of both Prochlorococcus and a high-PUB type of Synechococcus drastically decreased because of a bottom intrusion; however, the abundances rapidly increased due to the advection by a Kyucho. These advected cells increased from 4 to 17 August in the channel and Kitanada Bay. Changes in the abundance of low-PUB type of Synechococcus and eukaryotic picophytoplankton were less noticeable than those in the abundance of Prochlorococcus and high-PUB type. The present study demonstrated that oceanic picophytoplankton advected by the Kyucho could grow in the channel. However, abundances of low-PUB type and eukaryotic picophytoplankton increased higher than those of Prochlorococcus and high-PUB type did. Thus, these oceanic phytoplankters will be excluded when Kyucho does not occur for a long time. The co-occurrence of various types of picophytoplankton found in the channel is probably achieved by both Kyucho event and their growth capability in the channel. 相似文献
18.
根据2014年8月和10月、2015年2月和5月使用单船底拖网进行的4个航次调查数据,对山东半岛近岸海区的莱州湾及渤海南部、山东半岛北部和山东半岛南部等3个海域蟹类种类组成、时空分布、优势种、群落结构稳定性等群落结构特征进行了研究。结果显示,4次调查共捕获蟹类20种,隶属于10科17属,其中日本蟳（Charybdis japonica）和三疣梭子蟹（Portunus trituberculatus）是主要经济种类,其余均为小型饵料型蟹类;海区内主要的优势种为双斑蟳（Charybdis bimaculata）、日本蟳（Charybdis japonica）和三疣梭子蟹（Portunus trituberculatus）,3个海域优势种季节更替均十分明显;莱州湾及渤海南部和山东半岛南部2个海域生物量季节变化明显,春季较低,在夏季达到峰值,夏季到冬季呈降低趋势,山东半岛北部海域生物量季节变化不明显。3个海域蟹类群落物种多样性指数（H'）、丰富度指数（D）及均匀度指数（J'）均处于较低水平,并有一定的季节变化;水深、水温和盐度是影响蟹类群落结构的重要因子,渤莱沿岸流、黄海暖流和黄海冷水团通过影响海域内水温与盐度影响蟹类群落结构。研究表明山东半岛近岸海区蟹类以小型饵料型蟹类为主,蟹类多样性水平较低,优势种更替明显,群落季节更替指数较高,季节间迁移频繁,蟹类群落不稳定。 相似文献
19.
The effects of long-term preservation on flow cytometric parameters of natural oceanic populations of pico-and nanophytoplankton
have been examined. Populations collected at oligotrophic subtropical and subarctic locations in the North Pacific were fixed
with glutaraldehyde and frozen in liquid nitrogen, according to Vaulot et al. (1989). During six months’ storage, chlorophyll red fluorescence declined in all the groups examined, while forward light
scatter was enhanced in Synechococcus and Prochlorococcus, and weakened in nanoeucaryotes. Cell loss was not significant except for Synechococcus. Caution is required when analyzing flow cytometric data of samples stored for more than a month. 相似文献
20.
为了利用南极微生物资源、探索南极罗斯海区域可培养微生物多样性,利用传统平板培养法对中国第33次南极科学考察采自南极罗斯海6个站位的海洋沉积物样品进行了细菌、真菌的分离培养。经细菌16S rRNA、真菌ITS基因序列检测及系统发育分析,共获得5个属的36株细菌和6个属的29株真菌。其中嗜冷杆菌属为优势细菌类群,枝孢属为优势真菌类群。该结果表明南极罗斯海区域具有丰富的微生物多样性。细菌API 20 NE生理生化及真菌产胞外酶活性实验显示,分离得到的细菌和真菌绝大多数都有低温酶活性。研究结果为南极罗斯海区域可培养微生物的多样性认识和低温酶产生菌资源获取与开发利用提供了支撑。 相似文献