Aerobic anoxygenic phototrophs are highly abundant in hypertrophic and polyhumic waters

ABSTRACT Aerobic anoxygenic phototrophs (AAPs) are a group of photoheterotrophic bacteria common in natural waters. Here, AAP abundance and contribution to total bacterial abundance and biomass were investigated to test whether the trophic status of a lake or content of coloured dissolved organic matter (CDOM) play a role in determining AAP distribution and abundance in shallow inland lakes, with special focus on hypertrophic and polyhumic waters. Twenty-six different shallow lakes in Hungary were monitored. AAP abundance and biomass were determined by epifluorescence microscopy. The lakes exhibit a broad range of CDOM (2–7000 mg Pt L−1) and phytoplankton biomass (2–1200 μg L−1 chlorophyll a concentration). Very high AAP abundance (up to 3 × 107 cells mL−1) was observed in polyhumic and hypertrophic shallow lakes. AAP abundance was influenced by phytoplankton biomass and CDOM content, and these effects were interrelated. As determined, 40 μg L−1 chlorophyll a and 52 mg Pt L−1 CDOM are threshold levels above which these effects have a synergistic relationship. Hence, the observed high AAP abundance in some soda pans is a consequence of combined hypertrophy and high CDOM content. AAP contribution was influenced by total suspended solids (TSS) content: the success of AAP cells could be explained by high TSS levels, which might be explained by the decrease of their selective grazing control.

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Phytoplankton biomass and chlorophyll-a in some shallow lakes in central Europe

Hydrobiologia ◽

10.1007/bf00014715 ◽

1991 ◽

Vol 215 (2) ◽

pp. 111-119 ◽

Cited By ~ 60

Author(s):

Lajos Vörös ◽

Judit Padisák

Keyword(s):

Chlorophyll A ◽

Central Europe ◽

Shallow Lakes ◽

Phytoplankton Biomass

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Temporal Changes and Altitudinal Distribution of Aerobic Anoxygenic Phototrophs in Mountain Lakes

Applied and Environmental Microbiology ◽

10.1128/aem.01526-13 ◽

2013 ◽

Vol 79 (20) ◽

pp. 6439-6446 ◽

Cited By ~ 28

Author(s):

Zuzana Čuperová ◽

Evelyn Holzer ◽

Ivette Salka ◽

Ruben Sommaruga ◽

Michal Koblížek

Keyword(s):

Altitudinal Gradient ◽

Alpine Lakes ◽

Temporal Changes ◽

Mountain Lakes ◽

Epifluorescence Microscopy ◽

Organic Substrates ◽

Altitudinal Distribution ◽

Anoxygenic Phototrophs ◽

Aerobic Anoxygenic Phototrophs ◽

Low Altitude

ABSTRACTAerobic anoxygenic phototrophs (AAPs) are bacteriochlorophylla-containing microorganisms that use organic substrates for growth but can supplement their energy requirements with light. They have been reported from various marine and limnic environments; however, their ecology remains largely unknown. Here infrared epifluorescence microscopy was used to monitor temporal changes in AAPs in the alpine lake Gossenköllesee, located in the Tyrolean Alps, Austria. AAP abundance was low (103cells ml−1) until mid-July and reached a maximum of ∼1.3 × 105cells ml−1(29% of all prokaryotes) in mid-September. We compared the studied lake with other mountain lakes located across an altitudinal gradient (913 to 2,799 m above sea level). The concentration of dissolved organic carbon and water transparency seem to be the main factors influencing AAP abundance during the seasonal cycle as well as across the altitudinal gradient. While the AAP populations inhabiting the alpine lakes were composed of intensely pigmented large rods (5 to 12 μm), the lakes below the tree line were inhabited by a variety of smaller morphotypes. Analysis ofpufMdiversity revealed that AAPs in Gossenköllesee were almost exclusivelySphingomonadalesspecies, which indicates that AAP communities inhabiting alpine lakes are relatively homogeneous compared to those in low-altitude lakes.

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In Vivo Fluorescence of Chlorophyll A: Estimation of Phytoplankton Biomass and Activity in Římov Reservoir (Czech Republic)

Water Science & Technology ◽

10.2166/wst.1993.0126 ◽

1993 ◽

Vol 28 (6) ◽

pp. 29-33 ◽

Cited By ~ 7

Author(s):

V. Vyhnálek ◽

Z. Fišar ◽

A. Fišarová ◽

J. Komárková

Keyword(s):

Czech Republic ◽

Chlorophyll Fluorescence ◽

Primary Production ◽

Chlorophyll A ◽

Phytoplankton Biomass ◽

In Vivo Fluorescence ◽

Fluorescence Of Chlorophyll A ◽

Římov Reservoir ◽

Natural Phytoplankton

The in vivo fluorescence of chlorophyll a was measured in samples of natural phytoplankton taken from the Římov Reservoir (Czech Republic) during the years 1987 and 1988. The fluorescence intensities of samples either with or without addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron, DCMU) were found reliable for calculating the concentration of chlorophyll a during periods when cyanobacteria were not abundant. The correction for background non-chlorophyll fluorescence appeared to be essential. No distinct correlation between a DCMU-induced increase of the fluorescence and primary production of phytoplankton was found.

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Differences between Nearshore and Offshore Phytoplankton Communities in Lake Ontario

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f87-264 ◽

1987 ◽

Vol 44 (12) ◽

pp. 2155-2163 ◽

Cited By ~ 33

Author(s):

I. M. Gray

Keyword(s):

Chlorophyll A ◽

Phytoplankton Biomass ◽

Algal Biomass ◽

Phytoplankton Community ◽

Seasonal Pattern ◽

Principal Component ◽

Lake Ontario ◽

Dominant Group ◽

Phytoplankton Communities ◽

Eutrophic Species

Differences between nearshore and offshore phytoplankton biomass and composition were evident in Lake Ontario in 1982. Phytoplankton biomass was characterized by multiple peaks which ranged over three orders of magnitude. Perhaps as a consequence of the three times higher current velocities at the northshore station, phytoplankton biomass ranged from 0.09 to 9.00 g∙m−3 compared with 0.10 to 2.40 g∙m−3 for the midlake station. Bacillariophyceae was the dominant group at the northshore station until September when Cyanophyta contributed most to the biomass (83%). Although Bacillariophyceae was the principal component of the spring phytoplankton community at the midlake station, phytoflagellates (49%) and Chlorophyceae (25%) were responsible for summer biomass, with the Chlorophyceae expanding to 80% in the fall. The seasonal pattern of epilimnetic chlorophyll a correlated with temperature. While chlorophyll a concentrations were similar to values from 1970 and 1972, algal biomass had declined and a number of eutrophic species (Melosira binderana, Stephanodiscus tenuis, S. hantzschii var. pusilla, and S. alpinus) previously found were absent in 1982.

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Spatiotemporal Variability of Surface Phytoplankton Carbon and Carbon-to-Chlorophyll a Ratio in the South China Sea Based on Satellite Data

Remote Sensing ◽

10.3390/rs13010030 ◽

2020 ◽

Vol 13 (1) ◽

pp. 30

Author(s):

Wenlong Xu ◽

Guifen Wang ◽

Long Jiang ◽

Xuhua Cheng ◽

Wen Zhou ◽

...

Keyword(s):

South China Sea ◽

Chlorophyll A ◽

South China ◽

Satellite Data ◽

Phytoplankton Biomass ◽

The South China Sea ◽

Spatiotemporal Variability ◽

The South ◽

Chl A ◽

China Sea

The spatiotemporal variability of phytoplankton biomass has been widely studied because of its importance in biogeochemical cycles. Chlorophyll a (Chl-a)—an essential pigment present in photoautotrophic organisms—is widely used as an indicator for oceanic phytoplankton biomass because it could be easily measured with calibrated optical sensors. However, the intracellular Chl-a content varies with light, nutrient levels, and temperature and could misrepresent phytoplankton biomass. In this study, we estimated the concentration of phytoplankton carbon—a more suitable indicator for phytoplankton biomass—using a regionally adjusted bio-optical algorithm with satellite data in the South China Sea (SCS). Phytoplankton carbon and the carbon-to-Chl-a ratio (θ) exhibited considerable variability spatially and seasonally. Generally, phytoplankton carbon in the northern SCS was higher than that in the western and central parts. The regional monthly mean phytoplankton carbon in the northern SCS showed a prominent peak during December and January. A similar pattern was shown in the central part of SCS, but its peak was weaker. Besides the winter peak, the western part of SCS had a secondary maximum of phytoplankton carbon during summer. θ exhibited significant seasonal variability in the northern SCS, but a relatively weak seasonal change in the western and central parts. θ had a peak in September and a trough in January in the northern and central parts of SCS, whereas in the western SCS the minimum and maximum θ was found in August and during October–April of the following year, respectively. Overall, θ ranged from 26.06 to 123.99 in the SCS, which implies that the carbon content could vary up to four times given a specific Chl-a value. The variations in θ were found to be related to changing phytoplankton community composition, as well as dynamic phytoplankton physiological activities in response to environmental influences; which also exhibit much spatial differences in the SCS. Our results imply that the spatiotemporal variability of θ should be considered, rather than simply used a single value when converting Chl-a to phytoplankton carbon biomass in the SCS, especially, when verifying the simulation results of biogeochemical models.

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The Deep Chlorophyll Maximum: Comparing Vertical Profiles of Chlorophyll a

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f82-108 ◽

1982 ◽

Vol 39 (5) ◽

pp. 791-803 ◽

Cited By ~ 537

Author(s):

John J. Cullen

Keyword(s):

Chlorophyll A ◽

Phytoplankton Biomass ◽

Physiological Adaptation ◽

Organic Carbon Content ◽

Deep Chlorophyll Maximum ◽

Vertical Profiles ◽

In Vivo Fluorescence ◽

Chlorophyll Maximum ◽

Vertical Distributions

The relationship between chlorophyll a and phytoplankton biomass (organic carbon content) is highly variable as is the yield of in vivo fluorescence per unit chlorophyll. Thus, vertical profiles of chlorophyll or in vivo fluorescence must be interpreted with caution if their ecological significance is to be established. Although the variability of carbon-to-chlorophyll ratios and fluorescence yield is large, much of it can be anticipated, corrected for, and usefully interpreted. Vertical profiles from different regions of the sea are presented; each has a deep chlorophyll maximum, but the probable mechanisms of their formation and maintenance differ widely. Most vertical distributions of chlorophyll can be explained by the interaction between hydrography and growth, behavior, or physiological adaptation of phytoplankton with no special consideration of grazing by herbivores, even though vertical distributions of epizooplankton are not uniform. The interaction between vertical profiles of zooplankton and chlorophyll will be better understood when the relationships between chlorophyll and phytoplankton biomass in those profiles is determined.Key words: chlorophyll a, fluorescence, phytoplankton, vertical structure

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Change in biomass of benthic and planktonic algae along a disturbance gradient for 24 Great Lakes coastal wetlands

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f03-054 ◽

2003 ◽

Vol 60 (6) ◽

pp. 676-689 ◽

Cited By ~ 26

Author(s):

Sheila A McNair ◽

Patricia Chow-Fraser

Keyword(s):

Water Quality ◽

Great Lakes ◽

Chlorophyll A ◽

Total Variation ◽

Coastal Wetlands ◽

Phytoplankton Biomass ◽

Wetland Management ◽

Percent Cover ◽

Planktonic Algae ◽

Wide Range

We quantified the chlorophyll a content of planktonic algae and benthic algae in periphyton on acrylic rods and in epiphyton growing on macrophytes in 24 coastal wetlands in all five Laurentian Great Lakes. Sites were selected to represent a wide range of environmental conditions ranging from nutrient-poor, clear-water marshes with abundant macrophytes to nutrient-enriched, turbid systems devoid of aquatic vegetation. Water quality and species and percent cover of submergent macrophytes were measured in each wetland. Principal components analysis (PCA) showed that total phosphorus, turbidity, and suspended solids, variables associated with human-induced degradation, were most strongly correlated with PC axis 1 (PC1), accounting for 69% of the total variation. The PC1 site score was significantly related to both periphyton and phytoplankton biomass, respectively accounting for 54 and 70% of the total variation in periphyton and phytoplankton data, whereas PC1 only accounted for 18% of the variation in epiphyton biomass. Periphytic and epiphytic biomass were negatively correlated with percent cover and species richness of submergent macrophytes, but phytoplankton biomass was not. We conclude that periphytic and planktonic chlorophyll a biomass are good indicators of human-induced water-quality degradation and recommend that both benthic and planktonic algal biomass should be routinely monitored as part of an effective wetland management program.

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