Dataset Information

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.

SUBMITTER: Brodersen KE

PROVIDER: S-EPMC5738630 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Publications

Seagrass-Mediated Phosphorus and Iron Solubilization in Tropical Sediments.

Brodersen Kasper Elgetti KE Koren Klaus K Moßhammer Maria M Ralph Peter J PJ Kühl Michael M Santner Jakob J

Environmental science & technology 20171206 24

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 O<sub>2</sub>, 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 pathw ...[more]

PMID: 29149570

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Dataset Information

Seagrass-Mediated Phosphorus and Iron Solubilization in Tropical Sediments.

Publications

Seagrass-Mediated Phosphorus and Iron Solubilization in Tropical Sediments.

Similar Datasets

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