The connection of phytoplankton biomass in the Marguerite Bay polynya of the western Antarctic Peninsula to the Southern Annular Mode

Antarctic coastal polynyas are biological hotspots in the Southern Ocean that support the abundance of hightrophic-level predators and are important for carbon cycling in the high-latitude oceans.In this study,we examined the interannual variation of summertime phytoplankton biomass in the Marguerite Bay polynya(MBP)in the western Antarctic Peninsula area,and linked such variability to the Southern Annular Mode(SAM)that dominated the southern hemisphere extratropical climate variability.Combining satellite data,atmosphere reanalysis products and numerical simulations,we found that the interannual variation of summer chlorophyll-a(Chl-a)concentration in the MBP is significantly and negatively correlated with the spring SAM index,and weakly correlated with the summer SAM index.The negative relation between summer Chl-a and spring SAM is due to weaker spring vertical mixing under a more positive SAM condition,which would inhibit the supply of iron from deep layers into the surface euphotic layer.The negative relation between spring mixing and spring SAM results from greater precipitation rate over the MBP region in positive SAM phase,which leads to lower salinity in the ocean surface layer.The coupled physical-biological mechanisms between SAM and phytoplankton biomass revealed in this study is important for us to predict the future variations of phytoplankton biomasses in Antarctic polynyas under climate change.

Spike in phytoplankton biomass in Greenland Sea during 2009 and the correlations among chlorophyll-a,aerosol optical depth and ice cover

The distributions and correlations of chlorophyll-a(Chl-a),aerosol optical depth(AOD)and ice cover in the southeast Arctic Ocean-Greenland Sea(10°W–10°E,70°–80°N)between 2003 and 2009 were studied using satellite data and statistical analyses.Regression analysis showed correlations between Chl-a and AOD,Chl-a and ice cover,and AOD and ice cover with different time lags.The time lag of Chl-a and AOD indicated their long-term equilibrium relationship.Peaks in AOD and Chl-a and generally occurred in May and July,respectively.Despite the time lag,the correlation between Chl-a and AOD in the study region was as high as 0.7.The peak gap between Chl-a and AOD shifted for about 6 weeks during 2003–2009.In the summer and autumn of 2009,Chl-a and AOD levels were much higher than during the other years,especially in the northern band of the study region(75°–80°N).The driving forces for this localized increase in phytoplankton biomass could be mainly attributed to the very high rate of ice melting in spring and early summer and the high wind speed in autumn,together with the increased deposition of aerosol throughout the year.The unusually high AOD in the spring of 2003 was mainly due to a massive fi re in Russia,which occurred in the fi rst half of the year.Over the 7 years of the study,the sea surface temperature generally decreased.This may have been due to the release of dimethylsulfi de into the air,excreted in large amounts from abundant phytoplankton biomass,and its subsequent reaction,form large amounts of aerosol,and resulting in regional cooling.

Simulation of phytoplankton biomass in Quanzhou Bay using a back propagation network model and sensitivity analysis for environmental variables

Prediction and sensitivity models,to elucidate the response of phytoplankton biomass to environmental factors in Quanzhou Bay,Fujian,China,were developed using a back propagation(BP) network.The environmental indicators of coastal phytoplankton biomass were determined and monitoring data for the bay from 2008 was used to train,test and build a three-layer BP artificial neural network with multi-input and single-output.Ten water quality parameters were used to forecast phytoplankton biomass(measured as chlorophyll-a concentration).Correlation coefficient between biomass values predicted by the model and those observed was 0.964,whilst the average relative error of the network was-3.46% and average absolute error was 10.53%.The model thus has high level of accuracy and is suitable for analysis of the influence of aquatic environmental factors on phytoplankton biomass.A global sensitivity analysis was performed to determine the influence of different environmental indicators on phytoplankton biomass.Indicators were classified according to the sensitivity of response and its risk degree.The results indicate that the parameters most relevant to phytoplankton biomass are estuary-related and include pH,sea surface temperature,sea surface salinity,chemical oxygen demand and ammonium.

Seasonal and spatial distributions of phytoplankton biomass associated with monsoon and oceanic environments in the South China Sea

Seasonal variations of phytoplankton/chlorophyll-a （Chl-a） distribution, sea surface wind, sea height anomaly, sea surface temperature and other oceanic environments for long periods are analyzed in the South China Sea （SCS）, especially in the two typical regions off the east coast of Vietnam and off the northwest coast of Luzon, using remote sensing data and other oceanographic data. The results show that seasonal and spatial distributions of phytoplankton biomass in the SCS are primarily influenced by the monsoon winds and oceanic environments. Off the east coast of Vietnam, Chl-a concentration is a peak in August, a jet shape extending into the interior SCS, which is associated with strong southwesterly monsoon winds, the coastal upwetling induced by offshore Ekman transport and the strong offshore current in the western SCS. In December, high Chl-a concentration appears in the upwelling region off the northwest coast of Luzon and spreads southwestward. Strong mixing by the strong northeasterly monsoon winds, the cyclonic circulation, southwestward coastal currents and river discharge have impacts on distribution of phytoplankton, so that the high phytoplankton biomass extends from the coastal areas over the northern SCS to the entire SCS in winter. These research activities could be important for revealing spatial and temporal patterns of phytoplankton and their interactions with physical environments in the SCS.

Seasonal Changes in Phytoplankton Biomass and Dominant Species in the Changjiang River Estuary and Adjacent Seas:General Trends Based on Field Survey Data 1959-2009

The characteristics of seasonal variation in phytoplankton biomass and dominant species in the Changjiang River Estuary and adjacent seas were discussed based on field investigation data from 1959 to 2009. The field data from 1981 to 2004 showed that the Chlorophyll-a concentration in surface seawater was between 0.4 and 8.5 ktg dm-3. The seasonal changes generally presented a bimodal trend, with the biomass peaks occurring in May and August, and Chlorophyll-a concentration was the lowest in winter. Seasonal biomass changes were mainly controlled by temperature and nutrient levels. From the end of autumn to the next early spring, phytoplankton biomass was mainly influenced by temperature, and in other seasons, nutrient level （including the nutrient supply from the terrestrial runoffs） was the major influence factor. Field investigation data from 1959 to 2009 demonstrated that dia- toms were the main phytoplankton in this area, and Skeletonerna costatum, Pseudo-nitzschia pungens, Coscinodiscus oculus-iridis, Thalassinoema nitzschioides, Paralia sulcata, Chaetoceros lorenzianus, Chaetoceros curvisetus, and Prorocentrum donghaiense Lu were common dominant species. The seasonal variations in major dominant phytoplankton species presented the following trends： 1） Skeletonema （mainly S. costatum） was dominant throughout the year; and 2） seasonal succession trends were Coscinodiscus （spring） →Chaetoceros （summer and autumn） → Coscinodiscus （winter）. The annual dominance of S. costatum was attributed to its environmental eurytopicity and long standing time in surface waters. The seasonal succession of Coscinodiscus and Chaetoceros was associated with the seasonal variation in water stability and nutrient level in this area. On the other hand, long-term field data also indicated obvious interannual variation of phytoplankton biomass and community structure in the Changjiang River Estuary and adjacent seas： average annual phytoplankton biomass and dinoflagellate proportion both presented increased trends during the 1950s - 2000s.

PHYTOPLANKTON BIOMASS (chl α) IN THE TAIWAN STRAIT (1997 - 1999)

The concentration, distribution, size-fraction structure and diurnal variation of phyto-plankton biomass ( chl α) in the Taiwan Strait were investigated during four cruises conducted in the summer (August) of 1997, 1998, 1999 and winter (February-March) of 1998, respectively. The results showed that phytoplankton biomass in the Taiwan Strait was largely influenced by water masses and up-welling, high biomass mainly occurred at the frontal zones. Nano-and pico-phytoplankton dominated the phytoplankton biomass and primary productivity in the Taiwan Strait, they contributed 60% - 80% to biomass and 80% to primary productivity. But size-fractionated phytoplankton biomass was quite different in the northern Taiwan Strait (NTS) and southern Taiwan Strait (STS), and varied significantly annually. Diurnal variation of chl α concentration in the water column and water layers indicated that phytoplankton biomass at most stations had one-day variation cycle, with some difference, which coincide with the tidal rhythm. The diurnal variation of the size-fractionated structure of phytoplankton biomass was strongly influenced by the hydrodynamics and grazing pressure of zooplankton. This study also showed that unusual phenomena observed in phytoplankton biomass during the investigating periods might be the biological response to ENSO events.

Estimating biomass of phytoplankton in the Jiaozhou Bay I. Phytoplankton biomass estimated from cell volume and plasma volume

Based on the data of the Jiaozhou Bay Ecosystem Dynamic Research, cell volume and sur face area of 87 common phytoplankton species in China sea waters were calculated with assignment of the similar geometric form. The cell plasma volume, live weight, Carbon content and nitrogen content were also calculated with the methods of Mullin et al. (1966), Strathmann (1967), Eppley et al. (1970), and Taguchi (1976). After comparing these methods, we chase the method of Eppley et al. (1970) as the hot method for calculating phytoplankton carbon content in China sea waters.

Spatial and temporal dynamics of phytoplankton and bacterioplankton biomass in Sanya Bay, northern South China Sea

The composition of phytoplankton and the dynamics of phytoplankton and bacterioplankton biomass （PB and BB, respectively） of Sanya Bay, South China Sea, were determined. A total of 168 species （67 genera） phytoplankton were identified, including BaciUariophyta （diatom, 128 species）, Pyrrophyta （35 species）, Cyanophyta （3 species）, and Chrysophyta （2 species）. Annual average zbundance of phytoplankton was 1.2 × 107 cells/m^3, with the highest abundance in autumn, and the lowest in summer. Annual average diversity index （H＇） and evenness （J） values were 3.96 and 0.70, respectively. Average chlorophyll-a was 2.5 mg/m^3, and the average PB was 124 mg C/m^3, with the highest value in autumn. Surface PB was higher than the bottom, except for summer. Annual mean bacterioplankton abundance and BB were 6.9 × 10^1l cells/m^3 and 13.8 mg C/m^3, respectively. The highest BB was found in summer, followed by winter, spring, and autumn. Surface BB was higher than bottom all year round. The spatial distribution patterns of PB and BB were very similar with the highest biomass in the estuary, and decreased seaward, primarily due to the terrestrial input from the Sanya River and influx of oceanic water. The main factor influencing PB and BB was dissolved inorganic nitrogen （DIN）. Other factors such as temperature, which is above 22℃ throughout the year, had a negligible impact. The correlation between BB and PB was significant （P 〈 0.01）. The annual average ratio of BB/PB was 0.12 （0.06-0.15）. Phytoplankton primary production was one of the most important factors in controlling the distribution of bacterioplankton.

Seasonality in Abundance, Biomass and Production of the Phytoplankton of Welala and Shesher Wetlands, Lake Tana Sub-Basin (Ethiopia)

The species composition and production of the phytoplankton community of the Shesher and Welala floodplain Wetlands, on the eastern side of Lake Tana, were studied during four seasons from July 2009 to May 2010. We investigated the spatial and temporal dynamics of phytoplankton, densities, biomass, in relation to physico-chemical conditions. Gross and net primary production was studied at one site in each Wetland. Temperature, dissolved oxygen, conductivity, Secchi-disc depth, nitrate, phosphate and silicate concentrations showed significant temporal variation (p 0.05). Thirty six phytoplankton genera/species, belonging to 7 higher taxa were identified. The Chlorophyta dominated the phytoplankton community and contributed 42% - 53 % of the total observed phytoplankton numbers. Average phytoplankton biomass (chlorophyll a content) over four seasons ranged from 9 - 121 μg.l-1 in Shesher and from 27 - 206 μg.l-1 in Welala, whereas the average gross primary production over three seasons was 10.5 in Shesher and 7.7 mg.O2l-1d-1 in Welala. The peak concentration of chlorophyll a was observed in the pre-rainy season, which coincided with a bloom of Microcystis spp. Both Shesher and Welala Wetlands are very productive and have a good water quality but they are threatened by low water inputs since in the summer of 2009 the construction of a dam by local people and facilitated by local officials prevented overflow from Ribb River into the Wetlands. We conclude that the good water quality, the relative high water temperature and high primary productivity make the two Wetlands suitable for culture based fisheries and/or aquaculture, but a wise water resource management is crucially important.

Size structure of biomass and primary production of phytoplankton：environmental impact analysis in the Dongsha natural gas hydrate zone, northern South China Sea

The size-fractionated biomass and primary production of phytoplankton, and the influence of environmental factors on it were studied in the Dongsha natural gas hydrate zone of the northern South China Sea in May 2013.Low nutrient, low chlorophyll a（Chl a） and primary productivity characteristics were found in these waters. The phenomena of subsurface Chl a maximum layers（SCMLs） and primary production maximum layers（SPMLs）were observed in the Dongsha waters. There were significant differences in the size-fractionated biomass and primary production that showed picophytoplankton〉nanophytoplankton〉microphytoplankton in terms of biomass and degree of contribution to production. Vertical biomass distribution indicated there were considerable differences among different phytoplankton within the euphotic zone（Zeu） in spring. For example,microphytoplankton was distributed evenly in the euphotic layer and nanophytoplankton was mainly distributed in the subsurface or in the middle of the euphotic layer, while picophytoplankton was mainly distributed in the middle or bottom of the euphotic layer. Smaller cell size and larger relative surface area allow picophytoplankton to benefit from nutrient competition and to hold a dominant position in the tropical oligotrophic waters of low latitudes. There was a positive correlation between size-fractionated biomass and temperature with pH and a negative correlation between size-fractionated biomass and silicate with phosphate. There was a positive correlation between size-fractionated primary production and temperature and a negative correlation between size-fractionated biomass and salinity with phosphate. Phosphate was an important factor influencing the size structure of phytoplankton. Meanwhile, irradiation and the euphotic layer were more important in regulating the vertical distribution of size-fractionated phytoplankton in the Dongsha natural gas hydrate zone.

Abundance,biomass and composition of spring ice algal and phytoplankton communities of the Laptev Sea(Arctic)

Abundance, biomass and composition of the ice algal and phytoplankton communities were investigated in the southeastern Laptev Sea in spring 1999. Diatoms dominated the algal communities and pennate diatoms dominated the diatom population. 12 dominant algal species occurred within sea ice and underlying water column, including Fragilariopsis oceanica, F. cylindrus, Nitzschla frigida, N. promare, Achnanthes taeniata, Nitzschia neofrigida, Navicula pelagica , N. vanhoef fenii, N. septentrionalls, Melosiraarctica , Clindrotheca closterium and Pyramimonas sp. The algal abundance of bottom 10cm sea ice varied between 14.6 and 1562.2 × 10^4 cells 1^-1 with an average of 639.0 × 10^4 cells 1^-1 , and the algal biomass ranged from 7.89 to 2093.5μg C 1^-1 with an average of 886.9μg C1^-1 , which were generally one order of magnitude higher than those of sub-bottom ice and two orders of magnitude higher than those of underlying surface water. The integrated algal abundance and biomass of lowermost 20 cm ice column were averagely 7.7 and 12.2 times as those of upper 20 m water column, respectively, suggesting that the ice algae might play an important role in maintaining the coastal marine ecosystem before the thawing of sea ice. Ice algae influenced the phytoplankton community of the underlying water column. However, the ＂seeding＂ of ice algae for phytoplankton bloom was negligible because of the low phytoplankton biomass within the underlying water column.

Phytoplankton community changes indicated by biomarker from sediment in Prydz Bay, Antarctica

Biomarkers including brassicasterol, dinosterol and alkenone in sediments are used as indicators to reconstruct changes to the phytoplankton community in surface and sub-aerial sediments of Prydz Bay, Antarctica. The results indicate that the bio- marker records in surface and core sediment samples changed with time and space. The total content of phytoplankton biomarkers ranges from 391.0--1 470.6 ng.g-l. The phytoplankton biomass has increased in Prydz Bay over the past 100 years. This variation may be mainly related with climate change in the region. The total biomarker contents in surface sediments from 5 stations in Prydz Bay are in the range of 215.8--1 294.3 ng.g4. The phytoplankton biomass in Prydz Bay is higher than that outside of the bay. This is similar to the distributions of chlorophyll a, organic carbon and biogenic silica in surface waters determined through in situ investigation. Such consistency indicates a coupling between the bottom of the ocean and biogeochemical processes in the upper water.

Role of Transparent Exopolymer Particles on Phytoplankton Dynamics in a Subtropical Estuary,Cananeia-Iguape(Sp,Brazil)

Transparent Exopolymer Particles (TEP) has a known crucial role in vertical fluxes of carbon in the ocean and has been intensively studied in the last decade. Nevertheless, few studies have considered horizontal fluxes of TEP. These fluxes arise prominently between estuaries and the coast, where its importance is associated to the predominant horizontal transport. This is due both to the low density of the TEP agglomerate generated in low density waters of continental origin, and to the fact that the main component of the advective transport at estuarine regions is the horizontal one. In this study, the significance of TEP in the particulate matter exchange between estuary and coast was analyzed in the estuarine lagoon system of Cananéia-Iguape (southeast coast of Brazil). TEP, total seston (TS), organic seston (OS) and chlorophyll a (Chl.a) were analyzed over complete tidal cycles, during the dry and rainy seasons both at spring and neap tides. Horizontal fluxes and net transport rates of these variables were also calculated. TEP concentrations (max. 4991 μg Xeq/L) were almost one order of magnitude higher during the rainy season. TEP horizontal transport rates as high as 1.8 g Xeq. m/s were observed at the northern inlet of the system. In terms of particulate carbon, it represents 32.7 g TEP-C m/s or 4% of the OS transport rates. Our study quantifies the advective transport of TEP and their importance in particulate matter exchange between a subtropical estuarine system and the adjacent coastal region. Our results contribute to the knowledge of exopolimer particles dynamics in subtropical estuarine systems, and their relationship to phyto-plankton biomass and particulate matter.

STUDY ON THE PHYTOPLANKTON.IN A LARGE RESERVOIR

A comprehensive study on the community structure and function of the phytoplankton in Taipinghu Reservoir, the largest reservoir (9400 ha) in Anhui Province, China, was carried out dur ing 1985- 1986. A total of 175 species of algae belonging to 8 phyla and 87 genera was noted. The composition of phytoplankton was dominated by species of Chlorophyta, Cyanophyta and Bacillariophyta. The species number, cell density and biomass of the three groups were respectively 88%, 86.5% and 78.9% of the total phytopiankton. The weighted annual average biomass was 1.52 mg/L and cell density was 1.43 x 106 ind/L. The growth maximum was observed in summer. Diatoms were abundant in the region adjoining a river. A large number of flagellated algae such as Euglena and Chromulina occurred in the artificial fish culture bay.It can be inferred from the algal composition and total nitrogen concentration (1.48mg/L) that this reservoir is a mesotrophic water body that had undergone slight natural eutrophication.Presented are

A Model Study on Dynamical Processes of Phytoplankton in Laizhou Bay

A three-dimensional ecosystem model, using a PIC(Particle-In-Cell) method, is developed to reproduce the annual cycle and seasonal variation of nutrients and phytoplankton biomass in Laizhou Bay. Eight state variables, i.e., DIN(dissolved inorganic nitrogen), phosphate, DON(dissolved organic nitrogen), DOP(dissolved organic phosphorus), COD(chemical oxygen demand), chlorophyll-a(Chl-a), detritus and the zooplankton biomass, are included in the model. The model successfully reproduces the observed temporal and spatial variations of nutrients and Chl-a biomass distributions in the bay. The nutrient concentrations are at high level in winter and at low level in summer. Double-peak structure of the phytoplankton(PPT) biomass exists in Laizhou Bay, corresponding to a spring and an autumn bloom respectively. Several numerical experiments are carried out to examine the nutrient limitation, and the importance of the discharges of the Yellow River and Xiaoqinghe River. Both DIN limitation and phosphate limitation exist in some areas of the bay, with the former being more significant than the latter. The Yellow River and Xiaoqinghe River are the main pollution sources of nutrients in Laizhou Bay. During the flood season, the algal growth is inhibited in the bay with the Yellow River discharges being excluded in the experiment, while in spring, the algal growth is enhanced with the Xiaoqinghe River excluded.

Seasonal change of ice algal and phytoplankton assemblages in the Nella Fjord near Zhongshan Station, East Antarctica

The ice algal and phytoplankton assemblages were studied from Nella Fjord near Zhongshan Station, East Antarctica from April 12 to December 30, 1992. Algal blooms occurred about 3 cm thick on the bottom of sea ice in late April and mid November to early December respectively, and a phytoplankton bloom appeared in the underlying surface water in mid December following the spring ice algal bloom. The biomass in ice bottom was 1 to 3 orders of magnitude higher than that of surface water. Amphiprora kjellmanii, Berkeleya sp., Navicula glaciei, Nitzschia barkelyi, N. cylindrus /N. curta, N. lecointei and Nitzschia sp. were common in the sea ice temporarily or throughout the study period. The biomass in a certain ice segment was decreased gradually and the dominant species were usually succeeded as the season went on. Nitzschia sublineata and Dactyliosolen antarctica were two seasonal dominant species only observed in underlying water column. The assemblages between bottom of ice and underlying surface water were different except when spring ice algae bloomed. The evidence shows that the ice algal blooms occurred mainly by in situ growth of ice algae, and the phytoplankton bloom was mostly caused by the release of ice algae.

砷污染治理背景下阳宗海浮游植物生物量的时空分布模式及驱动因子

在社会经济发展和流域开发持续的背景下,砷污染已成为我国部分水体面临的重要环境问题,目前对砷污染防控的生态效应与修复效果评价仍缺乏系统识别。湖泊生态系统中浮游植物是重要的生产者,砷等重金属污染可以直接影响浮游植物生长、物种演替和初级生产力水平,浮游植物已成为指示砷污染水平及其生态效应的敏感指标。本研究以长期受到砷污染胁迫并经历污染治理的阳宗海为研究对象,设置南、中、北3个调查位点,于2015年4月-2019年12月对浮游植物和水质因子开展季节调查和空间分析,通过识别浮游植物生物量的时空分布模式与驱动因子,评价了砷污染与治理下浮游植物生物量的变化机制和生态修复效果。调查结果显示,采样期间阳宗海浮游植物以蓝藻门为主,浮游植物的生物量范围为0.7~30.4 mg/L,平均生物量在2016年最低((3.0±1.8)mg/L)、在2017年最高((10.5±8.9)mg/L)。ANOVA分析结果显示,浮游植物生物量存在显著的季节差异而空间差异不明显。相关分析结果显示,阳宗海浮游植物生物量与砷浓度和透明度呈显著负相关,而与水体温度和p H呈显著正相关。多元线性回归分析进一步显示,砷和水温是驱动阳宗海浮游植物生物量变化的显著环境因子。由此可见,在重金属污染湖泊经过修复后,水体砷遗留物的毒性效应仍然对浮游植物生长产生了明显的抑制作用,表明了水体重金属污染物可能具有长期的沉积物释放作用与持久的生态毒理效应。

云南长桥海浮游植物群落结构的季节变化特征及其影响因子识别

于2017年6月、9月、12月和2018年3月对长桥海浮游植物生物量及群落结构进行调查,分析浮游植物的季节变化特征及其与环境因子的关系.研究结果显示浮游植物生物量的范围为17.9~60.5 mg/L,9月最高,6月最低.浮游植物群落由蓝藻门、绿藻门、硅藻门、甲藻门、裸藻门、隐藻门和金藻门组成,其中蓝藻门的生物量占绝对优势.浮游植物优势属种(相对生物量百分比>10%)为蓝藻门的泽丝藻(Limnothrix spp.)、拟柱孢藻(Raphidiopsis raciborskii)和假鱼腥藻(Pseudanabaena spp.).方差分析(ANOVA)和相似性分析(ANOSIM)的结果显示浮游植物生物量和群落结构(门水平和属水平)均在季节上存在显著差异.Pearson相关分析表明浮游植物总生物量与TN、N∶P、NO 3-N呈显著正相关关系.冗余分析(RDA)结果显示WT、TN、TP、N∶P和NO 3-N是影响浮游植物群落结构变化的显著因子,方差分解分析(VPN)进一步表明WT、TN和TP是影响长桥海浮游植物群落变化的关键环境因子,三者分别单独解释了浮游植物变化的12.6%、20.9%和5.1%,温度和总磷共同解释了群落变化的2.1%,TN和TP共同解释了群落变化的1.1%.

南极冰间湖浮游植物生物量和生物生产力时空特征及影响因素研究进展

南极冰间湖在气候变化中和生态系统环境中扮演着重要角色。本文通过回顾南极罗斯海、阿蒙森海、松岛和默茨等4个冰间湖浮游植物生物量和生产力的时空分布特征和变化规律、物理环境参数和气候模态对冰间湖中叶绿素a和浮游植物水华开始及持续时间的影响,得出以下几点结论:(1)罗斯海冰间湖是南极近海生物生产力最高的区域,占南大洋总生产力的28%;阿蒙森海和松岛冰间湖在37个南极冰间湖生态系统中单位面积的生产力最高;默茨冰间湖浮游植物生物量年际变化明显。(2)海冰密集度、风速和云量等物理参数与浮游植物生物量变化密切相关,其相关关系的季节性和地域特征明显。海冰密集度主要通过改变冰间湖开放水域的面积来影响可到达海表的光合有效辐射;风速通过影响水体的垂直混合强度来改变营养盐及浮游植物的垂向输运;云量对冰间湖生态系统的影响是可见光强度及紫外线辐射量之间平衡的结果。(3)在部分冰间湖,浮游植物生物量的年际变化同调控南半球高纬度气候的主要模态,如南半球环状模和半年振荡等存在显著相关性。未来工作可结合长期卫星遥感观测、现场观测和数值模拟,进一步开展气候模态对冰间湖浮游植物生物量年际变化的物理-生态耦合机制、冰间湖生态系统生产力各个尺度变异规律和机制等的深入探究,从而更好地认知极地关键海区的生物地球化学循环过程及其气候效应。

高邮湖浮游生物多样性分析

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