Seagrass-mediated phosphorus and iron solubilization in tropical sediments

Kasper Elgetti Brodersen; Klaus Koren; Maria Mosshammer; Peter J. Ralph; Michael Kühl; Jakob Santner

doi:10.1021/acs.est.7b03878

Seagrass-mediated phosphorus and iron solubilization in tropical sediments

Kasper Elgetti Brodersen, Klaus Koren, Maria Mosshammer, Peter J. Ralph, Michael Kühl, Jakob Santner

Marine Biology

39 Citations (Scopus)

114 Downloads (Pure)

Abstract

Tropical seagrasses are nutrient-limited owing to the strong phosphorus fixation capacity of carbonate-rich sediments, yet they form densely vegetated, multispecies meadows in oligotrophic tropical waters. Using a novel combination of high-resolution, two-dimensional chemical imaging of O₂, pH, iron, sulfide, calcium, and phosphorus, we found that tropical seagrasses are able to mobilize the essential nutrients iron and phosphorus in their rhizosphere via multiple biogeochemical pathways. We show that tropical seagrasses mobilize phosphorus and iron within their rhizosphere via plant-induced local acidification, leading to dissolution of carbonates and release of phosphate, and via local stimulation of microbial sulfide production, causing reduction of insoluble Fe(III) oxyhydroxides to dissolved Fe(II) with concomitant phosphate release into the rhizosphere porewater. These nutrient mobilization mechanisms have a direct link to seagrass-derived radial O₂ loss and secretion of dissolved organic carbon from the below-ground tissue into the rhizosphere. Our demonstration of seagrass-derived rhizospheric phosphorus and iron mobilization explains why seagrasses are widely distributed in oligotrophic tropical waters.

Original language	English
Journal	Environmental Science & Technology
Volume	51
Issue number	24
Pages (from-to)	14155-14163
Number of pages	9
ISSN	0013-936X
DOIs	https://doi.org/10.1021/acs.est.7b03878
Publication status	Published - 19 Dec 2017

Access to Document

10.1021/acs.est.7b03878Licence: CC BY

Brodersen_2017_Seagrass_mediatedFinal published version, 6.71 MBLicence: CC BY

Cite this

@article{b52b7fb791fa460680afeb67abb251be,

title = "Seagrass-mediated phosphorus and iron solubilization in tropical sediments",

abstract = "Tropical seagrasses are nutrient-limited owing to the strong phosphorus fixation capacity of carbonate-rich sediments, yet they form densely vegetated, multispecies meadows in oligotrophic tropical waters. Using a novel combination of high-resolution, two-dimensional chemical imaging of O2, pH, iron, sulfide, calcium, and phosphorus, we found that tropical seagrasses are able to mobilize the essential nutrients iron and phosphorus in their rhizosphere via multiple biogeochemical pathways. We show that tropical seagrasses mobilize phosphorus and iron within their rhizosphere via plant-induced local acidification, leading to dissolution of carbonates and release of phosphate, and via local stimulation of microbial sulfide production, causing reduction of insoluble Fe(III) oxyhydroxides to dissolved Fe(II) with concomitant phosphate release into the rhizosphere porewater. These nutrient mobilization mechanisms have a direct link to seagrass-derived radial O2 loss and secretion of dissolved organic carbon from the below-ground tissue into the rhizosphere. Our demonstration of seagrass-derived rhizospheric phosphorus and iron mobilization explains why seagrasses are widely distributed in oligotrophic tropical waters.",

author = "Brodersen, {Kasper Elgetti} and Klaus Koren and Maria Mosshammer and Ralph, {Peter J.} and Michael K{\"u}hl and Jakob Santner",

year = "2017",

month = dec,

day = "19",

doi = "10.1021/acs.est.7b03878",

language = "English",

volume = "51",

pages = "14155--14163",

journal = "Environmental Science & Technology",

issn = "0013-936X",

publisher = "American Chemical Society",

number = "24",

}

TY - JOUR

T1 - Seagrass-mediated phosphorus and iron solubilization in tropical sediments

AU - Brodersen, Kasper Elgetti

AU - Koren, Klaus

AU - Mosshammer, Maria

AU - Ralph, Peter J.

AU - Kühl, Michael

AU - Santner, Jakob

PY - 2017/12/19

Y1 - 2017/12/19

N2 - Tropical seagrasses are nutrient-limited owing to the strong phosphorus fixation capacity of carbonate-rich sediments, yet they form densely vegetated, multispecies meadows in oligotrophic tropical waters. Using a novel combination of high-resolution, two-dimensional chemical imaging of O2, pH, iron, sulfide, calcium, and phosphorus, we found that tropical seagrasses are able to mobilize the essential nutrients iron and phosphorus in their rhizosphere via multiple biogeochemical pathways. We show that tropical seagrasses mobilize phosphorus and iron within their rhizosphere via plant-induced local acidification, leading to dissolution of carbonates and release of phosphate, and via local stimulation of microbial sulfide production, causing reduction of insoluble Fe(III) oxyhydroxides to dissolved Fe(II) with concomitant phosphate release into the rhizosphere porewater. These nutrient mobilization mechanisms have a direct link to seagrass-derived radial O2 loss and secretion of dissolved organic carbon from the below-ground tissue into the rhizosphere. Our demonstration of seagrass-derived rhizospheric phosphorus and iron mobilization explains why seagrasses are widely distributed in oligotrophic tropical waters.

AB - Tropical seagrasses are nutrient-limited owing to the strong phosphorus fixation capacity of carbonate-rich sediments, yet they form densely vegetated, multispecies meadows in oligotrophic tropical waters. Using a novel combination of high-resolution, two-dimensional chemical imaging of O2, pH, iron, sulfide, calcium, and phosphorus, we found that tropical seagrasses are able to mobilize the essential nutrients iron and phosphorus in their rhizosphere via multiple biogeochemical pathways. We show that tropical seagrasses mobilize phosphorus and iron within their rhizosphere via plant-induced local acidification, leading to dissolution of carbonates and release of phosphate, and via local stimulation of microbial sulfide production, causing reduction of insoluble Fe(III) oxyhydroxides to dissolved Fe(II) with concomitant phosphate release into the rhizosphere porewater. These nutrient mobilization mechanisms have a direct link to seagrass-derived radial O2 loss and secretion of dissolved organic carbon from the below-ground tissue into the rhizosphere. Our demonstration of seagrass-derived rhizospheric phosphorus and iron mobilization explains why seagrasses are widely distributed in oligotrophic tropical waters.

U2 - 10.1021/acs.est.7b03878

DO - 10.1021/acs.est.7b03878

M3 - Journal article

C2 - 29149570

SN - 0013-936X

VL - 51

SP - 14155

EP - 14163

JO - Environmental Science & Technology

JF - Environmental Science & Technology

IS - 24

ER -

Seagrass-mediated phosphorus and iron solubilization in tropical sediments

Abstract

Access to Document

Fingerprint

Cite this