Microbial nitrogen fixation and methane oxidation are strongly enhanced by light in Sphagnum mosses

Abstract. Sphagnum peatlands are important ecosystems in the methane cycle. Methanotrophs living inside the dead hyaline cells or on the Sphagnum mosses are able to act as a methane filter and thereby reduce methane emissions. We investigated in situ methane concentrations and the corresponding activity and diversity of methanotrophs in different Sphagnum dominated bog microhabitats. In contrast to the Northern Hemisphere peat ecosystems the temperate South American peat bogs are dominated by one moss species; Sphagnum magellanicum. This permitted a species-independent comparison of the different bog microhabitats. Potential methane oxidizing activity was found in all Sphagnum mosses sampled and a positive correlation was found between activity and in situ methane concentrations. Substantial methane oxidation activity (23 μmol CH4 gDW−1 day−1) was found in pool mosses and could be correlated with higher in situ methane concentrations (>35 μmol CH4 l−1 pore water). Little methanotrophic activity (<0.5 μmol CH4 gDW−1 day−1) was observed in living Sphagnum mosses from lawns and hummocks. Methane oxidation activity was relatively high (>4 μmol CH4 gDW−1 day−1) in Sphagnum litter at depths around the water levels and rich in methane. The total bacterial community was studied using 16S rRNA gene sequencing and the methanotrophic communities were studied using a pmoA microarray and a complementary pmoA clone library. The methanotrophic diversity was similar in the different habitats of this study and comparable to the methanotrophic diversity found in peat mosses from the Northern Hemisphere. The pmoA microarray data indicated that both alpha- and gammaproteobacterial methanotrophs were present in all Sphagnum mosses, even in those mosses with a low initial methane oxidation activity. Prolonged incubation of Sphagnum mosses from lawn and hummock with methane revealed that the methanotrophic community present was viable and showed an increased activity within 15 days. The high abundance of methanotrophic Methylocystis species in the most active mosses suggests that these might be responsible for the bulk of methane oxidation.

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ELUCIDATING THE MOLECULAR RESPONSE OF MICROBIAL NITROGEN FIXATION IN ESTUARINE SEDIMENTS TO HYPOXIA

10.23860/thesis-ehrlich-andraya-2014 ◽

2014 ◽

Author(s):

◽

Andraya Ehrlich

Keyword(s):

Nitrogen Fixation ◽

Estuarine Sediments ◽

Molecular Response ◽

Microbial Nitrogen

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Microbial nitrogen cycling on the Greenland Ice Sheet

Biogeosciences Discussions ◽

10.5194/bgd-8-10423-2011 ◽

2011 ◽

Vol 8 (5) ◽

pp. 10423-10457 ◽

Cited By ~ 2

Author(s):

J. Telling ◽

M. Stibal ◽

A. M. Anesio ◽

M. Tranter ◽

I. Nias ◽

...

Keyword(s):

Nitrogen Fixation ◽

Nitrogen Cycling ◽

Microbial Growth ◽

Inorganic Nitrogen ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Available Nitrogen ◽

Microbial Nitrogen ◽

Nitrogen Demand

Abstract. Microbial nitrogen cycling was investigated along a 79 km transect into the Greenland Ice Sheet (GrIS) in early August 2010. The depletion of dissolved nitrate and production of ammonium (relative to icemelt) in cryoconite holes within 7.5 km of the ice sheet margin suggested microbial uptake and ammonification respectively. Nitrogen fixation (<4.2 μmoles C2H4 m−2 day−1 to 16.3 μmoles C2H4 m−2 day−1) was active in some cryoconite holes at sites up to 5.7 km from the ice sheet margin, with nitrogen fixation inversely correlated to concentrations of inorganic nitrogen. There may be the potential for the zone of nitrogen fixation to progressively extend further into the interior of the GrIS as the melt season progresses as reserves of available nitrogen are depleted. Estimated annual inputs of nitrogen from nitrogen fixation along the transect were at least two orders of magnitude lower than inputs from precipitation, with the exception of a 100 m long marginal debris-rich zone where nitrogen fixation could potentially equal or exceed that of precipitation. The average estimated contribution of nitrogen fixation to the nitrogen demand of net microbial growth at sites along the transect ranged from 0% to 17.5%.

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Nitrogen fixation in Sphagnum mosses is affected by moss species and water table level

Plant and Soil ◽

10.1007/s11104-014-2356-6 ◽

2014 ◽

Vol 389 (1-2) ◽

pp. 185-196 ◽

Cited By ~ 30

Author(s):

Sanna M. Leppänen ◽

Antti J. Rissanen ◽

Marja Tiirola

Keyword(s):

Nitrogen Fixation ◽

Water Table ◽

Moss Species ◽

Sphagnum Mosses ◽

Water Table Level

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Investigation of cerium and yttrium ions effects on microbial nitrogen fixation and determination of inhibition

Zentralblatt für Bakteriologie Parasitenkunde Infektionskrankheiten und Hygiene Zweite Naturwissenschaftliche Abteilung Mikrobiologie der Landwirtschaft der Technologie und des Umweltschutzes ◽

10.1016/s0323-6056(78)80065-2 ◽

1978 ◽

Vol 133 (7-8) ◽

pp. 628-631

Author(s):

Krishna Bahadur ◽

Parveen Tripathi

Keyword(s):

Nitrogen Fixation ◽

Microbial Nitrogen

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Water Dispersal of Methanotrophic Bacteria Maintains Functional Methane Oxidation in Sphagnum Mosses

Frontiers in Microbiology ◽

10.3389/fmicb.2012.00015 ◽

2012 ◽

Vol 3 ◽

Cited By ~ 23

Author(s):

Anuliina Putkinen ◽

Tuula Larmola ◽

Tero Tuomivirta ◽

Henri M. P. Siljanen ◽

Levente Bodrossy ◽

...

Keyword(s):

Methane Oxidation ◽

Methanotrophic Bacteria ◽

Sphagnum Mosses ◽

Water Dispersal

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Assessing the effects of iron enrichment across holobiont compartments reveals reduced microbial nitrogen fixation in the Red Sea coralPocillopora verrucosa

Ecology and Evolution ◽

10.1002/ece3.3293 ◽

2017 ◽

Vol 7 (16) ◽

pp. 6614-6621 ◽

Cited By ~ 5

Author(s):

Nils Rädecker ◽

Claudia Pogoreutz ◽

Maren Ziegler ◽

Ananya Ashok ◽

Marcelle M. Barreto ◽

...

Keyword(s):

Nitrogen Fixation ◽

Red Sea ◽

Iron Enrichment ◽

Microbial Nitrogen

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Microbial nitrogen fixation in the gastro-intestinal tract of Kalmykia gerbils (M. tamariscinus and Meriones meridianus)

Biology Bulletin ◽

10.1134/s1062359010050067 ◽

2010 ◽

Vol 37 (5) ◽

pp. 476-479 ◽

Cited By ~ 4

Author(s):

T. A. Kuznetsova ◽

N. V. Kostina ◽

E. I. Naumova ◽

M. M. Umarov

Keyword(s):

Nitrogen Fixation ◽

Intestinal Tract ◽

Microbial Nitrogen ◽

Gastro Intestinal Tract

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Methanotrophic activity and diversity in different <i>Sphagnum magellanicum</i> dominated habitats in the southernmost peat bogs of Patagonia

Biogeosciences Discussions ◽

10.5194/bgd-8-9357-2011 ◽

2011 ◽

Vol 8 (5) ◽

pp. 9357-9380 ◽

Cited By ~ 2

Author(s):

N. Kip ◽

C. Fritz ◽

E.S. Langelaan ◽

Y. Pan ◽

L. Bodrossy ◽

...

Keyword(s):

Methane Oxidation ◽

Northern Hemisphere ◽

Water Levels ◽

Peat Bogs ◽

Oxidation Activity ◽

Moss Species ◽

Sphagnum Mosses ◽

Methane Concentrations ◽

Sphagnum Magellanicum

Abstract. Sphagnum peatlands are important ecosystems in the methane cycle. Methanotrophs living in and on the Sphagnum mosses are able to act as a methane filter and thereby reduce methane emissions. We investigated in situ methane concentrations and the corresponding activity and diversity of methanotrophs in different Sphagnum dominated bog microhabitats. In contrast to the Northern Hemisphere peat ecosystems the temperate South American peat bogs are dominated by one moss species; Sphagnum magellanicum. This permitted a species-independent comparison of the different bog microhabitats. Potential methane oxidizing activity was found in all Sphagnum mosses sampled and a positive correlation was found between activity and in situ methane concentrations. Substantial methane oxidation activity (23 μmol CH4 gDW−1 day−1) was found in pool mosses and could be correlated with higher in situ methane concentrations (>35 μmol CH4 l−1 pore water). Little methanotrophic activity (<0.5 μmol CH4 gDW−1 day−1) was observed in living Sphagnum mosses from lawns and hummocks. Methane oxidation activity was relatively high (>4 μmol CH4 gDW−1 day−1) in Sphagnum litter situated at depths around the water levels and rich in methane. The total bacterial community was studied using 16S rRNA gene sequencing and the methanotrophic communities were studied using a pmoA microarray and a complementary pmoA clone library. The methanotrophic diversity was similar in the different habitats of this study and surprisingly comparable to the methanotrophic diversity found in peat mosses from the Northern Hemisphere. The pmoA microarray data indicated that both alpha- and gammaproteobacterial methanotrophs were present in all Sphagnum mosses, even in those mosses with a low initial methane oxidation activity. Prolonged incubation of Sphagnum mosses from lawn and hummock with methane revealed that the methanotrophic community present was viable and showed an increased activity within 15 days. The high abundance of methanotrophic Methylocystis species in the most active mosses suggests that these might be responsible for the bulk of methane oxidation.

Download Full-text