Representative measurement of two-dimensional reactive phosphate distributions and co-distributed iron(II) and sulfide in seagrass sediment porewaters

Pagès, Anaïs; Teasdale, Peter R.; Robertson, D.E.; Bennett, William W.; Schäfer, Jörg; Welsh, David T.

doi:10.1016/j.chemosphere.2011.07.020

Cited by 80 publications

(81 citation statements)

References 33 publications

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“…However, such high porewater ammonium concentrations (1000 up to 7000 M) have been observed before in eutrophic coastal sediments (Fourqurean et al, 1992;Murray et al, 1978;Pages et al, 2012). And the high porewater ammonium concentrations in our experiment enabled us to investigate the effects of this wide range of ammonium concentrations, which has been observed in natural coastal sediments.…”

Section: Ammonium Toxicitymentioning

confidence: 90%

Toxic effects of increased sediment nutrient and organic matter loading on the seagrass Zostera noltii

et al. 2014

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As a result of anthropogenic disturbances and natural stressors, seagrass beds are often patchy and heterogeneous. The effects of high loads of nutrients and organic matter in patch development and expansion in heterogeneous seagrass beds have, however, poorly been studied. We experimentally assessed the in situ effects of sediment quality on seagrass (Zostera noltii) patch dynamics by studying patch (0.35 m diameter) development and expansion for 4 sediment treatments: control, nutrient addition (NPK), organic matter addition (OM) and a combination (NPK+OM).OM addition strongly increased porewater sulfide concentrations whereas NPK increased porewater ammonium, nitrate and phosphate concentrations. As high nitrate concentrations suppressed sulfide production in NPK+OM, this treatment was biogeochemically comparable to NPK. Sulfide and ammonium concentrations differed within treatments, but over a 77 days period, seagrass patch survival and expansion were impaired by all additions compared to the control treatment.Expansion decreased at porewater ammonium concentrations >2000 mol L -1 .Mother patch biomass was not affected by high porewater ammonium concentrations as a result of its detoxification by higher seagrass densities. Sulfide 2 concentrations >1000 mol L -1 were toxic to both patch expansion and mother patch. We conclude that patch survival and expansion are constrained at high loads of nutrients or organic matter as a result of porewater ammonium or sulfide toxicity.

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Section: Ammonium Toxicitymentioning

confidence: 90%

Toxic effects of increased sediment nutrient and organic matter loading on the seagrass Zostera noltii

et al. 2014

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“…iron (II) and sulphide). Two-dimensional zonations of these reduced compounds have been shown to be highly heterogeneous in bioturbated sediments, particularly in the vicinity of burrows and roots (Robertson et al, 2009;Pagès et al, 2011), which could potentially drive variable fluxes of both reduced compounds and oxygen in the different part of the burrows.…”

Section: Oxygen Spatial Heterogeneitymentioning

confidence: 99%

Spatial oxygen heterogeneity in a Hediste diversicolor irrigated burrow

et al. 2011

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International audienceThe heterogeneity of oxygen distribution in a Hediste diversicolor burrow environment was investigated in a laboratory experiment using a 6-mm thick tank equipped with oxygen planar optodes. The twodimensional oxygen distribution in a complete burrow was monitored every 2 min for 4 h. Oxygen concentrations fluctuated over a scale of minutes in the burrow lumen and wall (up to 2 mm) reflecting the balance between worm ventilation activity and oxygen consumption. The magnitude of the three surrounding micro-horizons (oxic, oscillating and anoxic) induced by the intermittent worm ventilation was spatially and temporally variable within the structure. Oxygen variations appeared to be controlled by distance from the sedimentâwater interface and the direction of water circulation. Moreover, there was an apparent âbuffer effectâ, induced by the proximity to the overlyingwater, which reduced the variations of lumen and wall oxygen in the upper part of the structure. These results highlight the heterogeneous distribution and dynamics of oxygen associated with H. diversicolor burrows and ventilation activity. They also highlight the necessity of integrating this complexity into the current burrow-base models in order to estimate the ecological importance of burrowing species in coastal ecosystems

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“…The most recent developments in 2D imaging include simple colorimetric DET techniques for measuring Fe(II) and phosphate [15,16,[35][36][37][38] as well as a 2D DET technique for the measurement of NO 3 À and N 2 isotopic composition [39]. These approaches are discussed in more detail below.…”

Section: Detmentioning

confidence: 99%

“…The DGT technique has since been adopted as an analytical tool for the determination of the availability of nutrients and contaminants to terrestrial [42,43] and aquatic organisms [44], complex dissociation kinetics [45] and also for 2D chemical imaging of the distribution of labile chemical species in both, soils and sediments [11][12][13]15,36,[46][47][48][49][50][51][52][53][54][55][56][57][58][59].…”

Section: Dgtmentioning

confidence: 99%

Two decades of chemical imaging of solutes in sediments and soils – a review

Santner

Larsen

Kreuzeder

et al. 2015

Analytica Chimica Acta

162

130

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The increasing appreciation of the small-scale (sub-mm) heterogeneity of biogeochemical processes in sediments, wetlands and soils has led to the development of several methods for high-resolution two-dimensional imaging of solute distribution in porewaters. Over the past decades, localised sampling of solutes (diffusive equilibration in thin films, diffusive gradients in thin films) followed by planar luminescent sensors (planar optodes) have been used as analytical tools for studies on solute distribution and dynamics. These approaches have provided new conceptual and quantitative understanding of biogeochemical processes regulating the distribution of key elements and solutes including O2, CO2, pH, redox conditions as well as nutrient and contaminant ion species in structurally complex soils and sediments. Recently these methods have been applied in parallel or integrated as so-called sandwich sensors for multianalyte measurements. Here we review the capabilities and limitations of the chemical imaging methods that are currently at hand, using a number of case studies, and provide an outlook on potential future developments for two-dimensional solute imaging in soils and sediments.

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Representative measurement of two-dimensional reactive phosphate distributions and co-distributed iron(II) and sulfide in seagrass sediment porewaters

Cited by 80 publications

References 33 publications

Toxic effects of increased sediment nutrient and organic matter loading on the seagrass Zostera noltii

Toxic effects of increased sediment nutrient and organic matter loading on the seagrass Zostera noltii

Spatial oxygen heterogeneity in a Hediste diversicolor irrigated burrow

Two decades of chemical imaging of solutes in sediments and soils – a review

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