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127 results on '"Allen, Deonie"'

6. Microplastics and nanoplastics in the marine-atmosphere environment

Author

Allen, Deonie, Allen, Steve, Abbasi, Sajjad, Baker, Alex, Bergmann, Melanie, Brahney, Janice, Butler, Tim, Duce, Robert A., Eckhardt, Sabine, Evangeliou, Nikolaos, Jickells, Tim, Kanakidou, Maria, Kershaw, Peter, Laj, Paolo, Levermore, Joseph, Li, Daoji, Liss, Peter, Liu, Kai, Mahowald, Natalie, Masque, Pere, Materić, Dušan, Mayes, Andrew G., McGinnity, Paul, Osvath, Iolanda, Prather, Kimberly A., Prospero, Joseph M., Revell, Laura E., Sander, Sylvia G., Shim, Won Joon, Slade, Jonathan, Stein, Ariel, Tarasova, Oksana, and Wright, Stephanie

Published
2022
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9. Beyond the design event : sediment pollution movement in SuDS

Author

Allen, Deonie, Haynes, Heather, and Arthur, Scott

Subjects
628
Abstract

Sustainable urban Drainage Systems (SuDS) present a ‘blue-green’ method of urban stormwater management that is increasingly implemented in the UK and worldwide. SuDS mimic natural vegetated flow paths and are designed to manage the increase in stormwater quantity and degradation of stormwater quality resulting from development (urbanisation). They have been widely implemented across the UK over the last 15 years, to aid compliance with the EU Water Framework Directive (2000) standards for river water quality. Given the increasing maturity of UK SuDS, there is growing concern over the long-term performance efficiencies of these assets/networks, particularly the variability of treatment efficiency over multiple flow events. Providing the field monitoring evidence base to address this concern forms the aim of the present thesis. Emphasis is placed upon understanding SuDS asset/network sediment detention efficiency, as the majority of urban pollution is adsorbed to sediment material rather than transported and treated as solute. A novel tracer method is, therefore, developed and employed to identify and quantify sediment processes for mature UK case study SuDS. SuDS design manuals (CIRIA 2015, Water by Design 2006, USEPA 2009) present expected or reported sediment detention and pollution mitigation levels for specific SuDS assets. For example, the expected Total Suspended Solids (TSS) removal for a swale has been defined as 90% in the WSUD (Water Sensitive Urban Design) technical manual (Leisenring et al. 2013). Yet, these treatment efficiencies are based on a single ‘design’ rainfall-runoff event through the system; hence, fail to consider the sensitivity of SuDS performance to non-design and multiple repeat events over the long term design life of the SuDS asset. As natural variability in rainfall affects pollutant washoff, shear stress for entrainment, conveyance, deposition, loss of treatment capacity etc., the research presented in the present thesis intensively monitored four established UK SuDS networks for 6-12 month timeframes. Bulk sampling data highlight that TSS treatment is highly variable, ranging from highly effective (>80%) to inefficient (< 20%). Similar variability is found in sediment deposition rates (on average: 0.4-1.1 kg/m2/yr), providing insight on temporal and asset dependency of fine sediment detention, including related treatment efficiency and long term loss of capacity. Wetlands illustrate the most effective (mass) sediment detention per area (>1kg/m2) while the swales detain the least (< 0.8kg/m2). To advance the volumetric data noted above, source-sink routing of diffuse fine sediment pollution required development of tracer methodology appropriate to use in SuDS. This dictated use of Rare Earth Oxides (REO) as fine sediment tags; although their use in an urban environment is new, it provides long term trace and experimental replicability results without loss of provenance, signature degradation or loss of tag material. Thus, unique time-stamped and source-specific identifiers have been used monitor their movement into and through each SuDS over a 6-12 month period. Use of REO tagged sediment data permits mass balance analysis of fine sediment through the monitored SuDS assets and networks. Data clearly illustrate that sediment is not fully detained (as assumed in SuDS design); rather, sediment is re-entrained and re-deposited multiple times over multiple flow events. Residence time of sediment within a full SuDS network is found to be as short as 12 weeks, raising concern over treatment capability. Reviewing this at finer asset-based resolution, detention efficiency and conveyance rates appear unique to each asset. Generally linear wetland and swale assets demonstrate the greatest (tagged) sediment detention efficiency (>70%) while (the monitored) wetland assets decline to below 50% efficiency over the first 12 months and ponds demonstrated negligible sediment detention efficiency (< 10%). As 80% of urban pollution is conveyed adsorbed to fine sediment, the sediment conveyance pattern through SuDS assets has been analysed to define the pollutant concentration levels and trends of detained sediment. Pollutant levels show no consistent trend across SuDS assets. Results illustrate that sediment pollutant contamination shows an influence from particle size distribution and mass deposition as well as asset design. Analysis shows the most numerous significantly elevated sediment pollutant concentrations within the linear wetland, with Fe, Ba, Cr, Cu, Zn, K and P demonstrating average concentrations above contaminated land thresholds. Enrichment and geoaccumulation indexing of pollutants illustrates Fe, Zn, Cr, Ba, Cu and P to be pollutants of concern, with Fe, Pb, Ni, Cr, Mn, Zn, Ba, Cu, Ni and P identified as hotspot pollutants in one or multiple SuDS assets. Cross-correlation of rainfall and flow characteristics with asset/network detention efficiencies were used to define key drivers of multi-event sediment conveyance. Outcomes highlight three variables of strong influence: the number of rainfall and flow occurrences; the antecedent dry days; rainfall clustering characteristics. Weaker correlations are found with flow characteristics (number of flow events, depth and velocity – leading to Fr and Re values) and modal particle size. These influential forcings have then been considered with respect to a selected standard SuDS pollution treatment process (MUSIC k-C*) to identify the compatibility for multiple rainfallrunoff event SuDS fine sediment and pollutant simulation. The research provides multiple event SuDS stormwater treatment efficiencies that can inform improved SuDS design and maintenance planning by engineering consultants, Local Authorities, environmental regulators and SuDS asset managers.

Published
2017

17. FRAM POLLUTION OBSERVATORY - MONITORING LITTER AND MICROPLASTIC AT HAUSGARTEN.

Author

Aves, Alexandra, Allen, Deonie, Bergmann, Melanie, and Allen, Steve

Abstract

This document provides an overview of a research expedition focused on assessing the presence of microplastics in the Arctic environment. The researchers collected ice cores, snow, meltwater, and seawater samples, as well as deep-sea organisms, for analysis. Preliminary results indicate that samples were successfully collected and prepared for analysis, with chemical identification of particles planned. The researchers aim to gain detailed insight into the movement and role of microplastics in the Arctic. The data collected will be archived and published according to international standards. [Extracted from the article]

Published
2023

24. Microplastics in the ice algae Melosira arctica - plasticising a vector to planktonic grazers and benthos

Author

Bergmann, Melanie, Krumpen, Thomas, Allen, Steven, and Allen, Deonie

Subjects
sympagic, ice algae, Arctic, cryosphere, sea ice
Abstract

Plastic pollution has become ubiquitous even in remote polar ecosystems such as the Arctic. Previous research at HAUSGARTEN observatory with Fram infrastructure has shown that microplastic concentrations are particularly high in water and sediment samples taken close to the marginal ice zone and in sea ice cores and zooplankton grazers associated with sea ice. Here, we analysed samples of the ice algae Melosira arctica that attach to ice floes and often form long filaments, curtains, nets and other growth forms, which could capture microplastics released from melting sea ice. Samples and field and procedural blanks were taken opportunistically in Fram Strait during a helicopter-based ice sampling campaign in summer 2021 and analysed by µ-Raman. Microplastics were found in all samples in significant quantities across a variety of polymer types and particles sizes. Whilst more data are needed our results indicate that ice algae could be an important sink and also accelerate the transport of microplastics to the deep seafloor, since ice algae are known to form aggregates that accelerate their sinking rates. Ice algae could thus also be vectors for microplastics into benthic or zooplankton food webs. Also see: https://micro2022.sciencesconf.org/427180/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano

Published
2022
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25. Global plastic treaty should address chemicals

Author

Dey, Tridibesh, primary, Trasande, Leonardo, additional, Altman, Rebecca, additional, Wang, Zhanyun, additional, Krieger, Anja, additional, Bergmann, Melanie, additional, Allen, Deonie, additional, Allen, Steve, additional, Walker, Tony R., additional, Wagner, Martin, additional, Syberg, Kristian, additional, Brander, Susanne M., additional, and Almroth, Bethanie Carney, additional

Published
2022
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29. Identifying hidden sinks of Arctic plastic pollution: Fram Pollution Observatory

Author

Bergmann, Melanie, Tekman, Mine Banu, Allen, Deonie, Gerdts, Gunnar, Gutow, Lars, Meyer, Anna Natalie, Peeken, Ilka, Primpke, Sebastian, Bergmann, Melanie, Tekman, Mine Banu, Allen, Deonie, Gerdts, Gunnar, Gutow, Lars, Meyer, Anna Natalie, Peeken, Ilka, and Primpke, Sebastian

Abstract

In 1999 the AWI established the HAUSGARTEN observatory, to assess the impact of climate change on Arctic ecosystems in Fram Strait (Arctic), which included repeated camera transects to assess changes on the deep Arctic seafloor. A first analysis of the footage highlighted that marine debris increased over time. Plastic debris was also sighted during sea surface observations for seabird surveys. This prompted us to add a pollution observatory to the ongoing research programme FRAM, aiming to quantify plastic pollution in different ecosystem compartments to identify hidden sinks. Here, we summarise the results of this work encompassing matrices such as snow, sea ice, surface waters, water column, deep seafloor, biota and Arctic beaches. Images from the deep seafloor taken since 2002 showed a marine debris concentration of 4,571 ± 1,628 items km-2, which is in range with polluted oceanic regions. Visual surveys of floating debris from the same region revealed 500 times lower concentrations (9 items km-2), showing that the deep Arctic seafloor constitutes a sink for marine debris. Quantities of 9–483 g m-2 were reported from 15 beach surveys on Svalbard by citizen scientists. Plastics accounted for >80% of the mass, primarily from fisheries. Microplastics in samples from the sea surface, water column, sediment, sea ice and snow were analysed by combining state-of–the-art sampling technology with µFT-IR analyses. Using the same analysis for samples from different ecosystem compartments enabled us to determine the vertical distribution of microplastics, as sea ice entrains extremely high microplastic concentrations, which are released to the underlying waters during ice melts. In-situ pump-filtrations throughout the water column revealed that microplastics prevail at all depths in Fram Strait (0–1,287 items m–3). Microplastic concentrations in sediments ranged from 239–13,331 N kg–1. Highest microplastics concentrations in sediments and the water column were measured clos

Published
2022

31. Source activation or fluvial transport – dynamic controls on spatial patterns and temporal dynamics of plastic pollution in river corridors

Author

Krause, Stefan, primary, Nel, Holly, additional, Schneidewind, Uwe, additional, Kukkola, Anna, additional, Drummond, Jennifer, additional, Kelleher, Liam, additional, Lynch, Iseult, additional, Sambrook Smith, Greg, additional, Runkel, Rob, additional, Allen, Deonie, additional, Allen, Steve, additional, Wazne, Mohammad, additional, Dendievel, Andre-Marie, additional, Simon, Laurent, additional, Mermillod-Blondin, Florian, additional, Haverson, Lee, additional, Yonan, Yasmin, additional, Mourier, Brice, additional, Piegay, Herve, additional, and Gomez-Velez, Jesus, additional

Published
2022
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36. Microplastics and nanoplastics in the marine-atmosphere environment

Author

Allen, Deonie, Allen, Steve, Abbassi, Sajjad, Baker, Alex, Bergmann, Melanie, Brahney, Janice, Butler, Tim, Duce, Robert A., Eckhardt, Sabine, Evangeliou, Nikolaos, Jickells, Tim, Kanakidou, Maria, Kershaw, P., Lai, Paolo, Levermore, Joseph, Li, Daoji, Liss, Peter, Liu, Kai, Mahowald, Natalie, Masque, Pere, Materić, Dušan, Mayes, Andrew, McGinnity, Paul, Osvath, Iolanda, Prather, Kimberly A., Prospero, Joseph, Revell, Laura E., Sander, Sylvia G., Shim, Won Joon, Slade, Jonathan, Stein, Ariel, Tarasova, Oksana, Wright, Stephanie, Allen, Deonie, Allen, Steve, Abbassi, Sajjad, Baker, Alex, Bergmann, Melanie, Brahney, Janice, Butler, Tim, Duce, Robert A., Eckhardt, Sabine, Evangeliou, Nikolaos, Jickells, Tim, Kanakidou, Maria, Kershaw, P., Lai, Paolo, Levermore, Joseph, Li, Daoji, Liss, Peter, Liu, Kai, Mahowald, Natalie, Masque, Pere, Materić, Dušan, Mayes, Andrew, McGinnity, Paul, Osvath, Iolanda, Prather, Kimberly A., Prospero, Joseph, Revell, Laura E., Sander, Sylvia G., Shim, Won Joon, Slade, Jonathan, Stein, Ariel, Tarasova, Oksana, and Wright, Stephanie

Abstract

The discovery of atmospheric micro(nano)plastic transport and ocean–atmosphere exchange points to a highly complex marine plastic cycle, with negative implications for human and ecosystem health. Yet, observations are currently limited. In this Perspective, we quantify the processes and fluxes of the marine-atmospheric micro(nano)plastic cycle, with the aim of highlighting the remaining unknowns in atmospheric micro(nano)plastic transport. Between 0.013 and 25 million metric tons per year of micro(nano)plastics are potentially being transported within the marine atmosphere and deposited in the oceans. However, the high uncertainty in these marine-atmospheric fluxes is related to data limitations and a lack of study intercomparability. To address the uncertainties and remaining knowledge gaps in the marine-atmospheric micro(nano)plastic cycle, we propose a future global marine-atmospheric micro(nano)plastic observation strategy, incorporating novel sampling methods and the creation of a comparable, harmonized and global data set. Together with long-term observations and intensive investigations, this strategy will help to define the trends in marine-atmospheric pollution and any responses to future policy and management actions.

Published
2021

39. Small but essential in hydrogeochemical cycles: headwater mountain catchments

Author

Le Roux, Gaël, primary, Haver, Marilen, additional, Rosset, Thomas, additional, Schmeller, Dirk, additional, Gandois, Laure, additional, Allen, Deonie, additional, Binet, Stéphane, additional, Simonneau, Anaelle, additional, Grusson, Youen, additional, Camboulives, Thierry, additional, Sauvage, Sabine, additional, Galop, Didier, additional, Gascoin, Simon, additional, and Sánchez Pérez, José Miguel, additional

Published
2020
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40. A Pilot Assessment of a 'Plastic Free Community' Initiative, Respective Community Actions and Residents' Behavior.

Author

MacDonald, Anna, Allen, Deonie, and João, Elsa

Subjects
*MICROPLASTICS, *MARINE pollution, *PUBLIC health, *SUSTAINABILITY, *MARINE ecology
Abstract

The problems of plastic pollution are increasing and have been linked to sustainability efforts. Some communities have tried to tackle this issue by implementing 'plastic free' initiatives, such as the 'Plastic Free Community'. Community initiatives foster change and encourage improved environmental outcomes; however, it is unclear if 'plastic free' initiatives have the capacity to 'snowball' into further sustainable behaviors or if they are a 'distraction' from more pressing environmental issues. This study presents the behavioral changes, snowball and distraction effects from the first Scottish mainland 'plastic free community' initiative. The pilot study of 'Plastic Free Anstruther' (Scotland) identifies self-transcending values and locus of control as important drivers for change, but adoption of single-use plastic alternatives and a 'single use' mindset resulted in a limited 'snowball' effect. Future 'Plastic Free Community' initiatives should focus on encouraging more circular approaches and individual behavior change to reduce waste and improve environmental outcomes. While the initiative resulted in greater awareness of wider environmental issues, additional incentives for individual and business pro-environmental behavior could further improve economic, social and environmental sustainability. [ABSTRACT FROM AUTHOR]

Published
2022
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43. Des contaminants venus d'ailleurs

Author

Simonneau, Anaëlle, Allen, Deonie, Le Roux, Gaël, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Biogéosystèmes Continentaux - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université de Toulouse (UT)

Subjects
microplastiques, [SDU]Sciences of the Universe [physics]
Abstract

National audience; C’est presque par hasard que des chercheurs ont trouvé des microplastiques dans les hautes montagnes pyrénéennes. Si lanouvelle est de prime abord déconcertante, elle apporte aux scientifiques de nouvelles données pour identifier les pollutionsissues de nos modes de vie.

Published
2019

44. Trace Metal Legacy in Mountain Environments

Author

Le Roux, Gaël, primary, Hansson, Sophia V., additional, Claustres, Adrien, additional, Binet, Stéphane, additional, Vleeschouwer, François, additional, Gandois, Laure, additional, Mazier, Florence, additional, Simonneau, Anaelle, additional, Teisserenc, Roman, additional, Allen, Deonie, additional, Rosset, Thomas, additional, Haver, Marilen, additional, Ros, Luca, additional, Galop, Didier, additional, Durantez, Pilar, additional, Probst, Anne, additional, Sánchez‐Pérez, Jose Miguel, additional, Sauvage, Sabine, additional, Laffaille, Pascal, additional, Jean, Séverine, additional, Schmeller, Dirk S., additional, Camarero, Lluis, additional, Marquer, Laurent, additional, and Lofts, Stephen, additional

Published
2020
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45. The short-term influence of cumulative, sequential rainfall-runoff flows on sediment retention and transport in selected SuDS devices

Author

Allen, Deonie, Haynes, Heather, Olive, Valerie, Allen, Steve, and Arthur, Scott

Subjects
TA
Abstract

It is necessary to understand Sustainable urban Drainage Systems (SuDS) sediment retention efficiencies to fully comprehend SuDS pollution removal properties and urban sediment movement from source-to sink. This research presents the detention and transport of a single tagged sediment release through four SuDS devices over 12 months, with the aim of quasi-quantifying these selected SuDS devices sediment detention efficiencies. Field monitoring and mass balance analysis of deposited sediment shows that tagged sediment from the single sediment release moves through the monitored SuDS, with deposition declining over the 12-month monitoring period. Initial retention is high (>80% during the first week of monitoring) but falls below 80% after multiple consecutive rainfall-runoff events (events ≤50% ARI). The field monitoring illustrates retention to generally remain above 50%, suggesting that SuDS are highly efficient at retaining urban sediment pollution but that deposition of a single sediment release may resuspend due to cumulative rainfall-runoff events.

Published
2018

47. An investigation into Holocene and Anthropocene pleolimnology records to identify driving forces of erosion and runoff in mountainous catchment areas (Pyrenees, France)

Author

Allen, Deonie, Simonneau, Anaëlle, Binet, Stéphane, Galop, Didier, Le Roux, Gael, Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Biogéosystèmes Continentaux - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Géographie de l'environnement (GEODE), Université Toulouse - Jean Jaurès (UT2J)-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), and Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)

Subjects
Holocene, [SDE.MCG]Environmental Sciences/Global Changes, Anthropocene, [SDE]Environmental Sciences, French Alps and Pyrenees, runoff, Paleolimnology, [SHS.GEO]Humanities and Social Sciences/Geography, erosion
Abstract

International audience; Significant research has been undertaken over the past two decades to identify and delineate flood event and long-term runoff erosion during the Holocene period. Recent published work focused in the French Alps and Pyrenees has illustrated capacity to use lacustrine sedimentary infill, reconstituted form dated lake core samples, to discuss Holocene (and earlier) runoff and flood occurrences within alpine catchments. Lake sediments trap various paleolimnology proxies, which can be examined to paint a detalied petrography, in combination with age-depth modelling, gives us the possibility to estimate the amount of soil eorded within the catchment through time. In mountainous areas, such erosion fluxes are expected to be essentially driven bt rainfall and runoff (energy and climate divers). The work-package 5 from the TRAM research project proposes to study the sedimentary infill form Lake Arbu, a small high-attitude system of glacial origin located into the French Pyrenees, in order to investigate the potential of paleo-limnological dataset to provide clear runoff and erosion proxies potentially capable of long-term semi-quantitative catchment erosion analysis. Combining sediment accumulation rates with quantitative organic petrography,andhydrological dynamics (rainfall and runoff characteristics) longer-term sediment mass balance analysis can be completed. De Ploey's Cumulative Erosion Potential (CEP) presents one such simple mass balance model. Similar to the earlier USLE, CEP provides a mass balance analysis based on rainfall (and discharge) datasets, providing consideration of soil moisture capacity and erosion susceptibility (Es) for a selected catchment. Correlation analysis of sediment accumulation rates with mass balance expected deposition, keymass balance parameters (including CEP, Es and the RUSLE K), sediment land use and climate characteristics is a first step in identification of possible paleo-limnological contributing catchment erosion rate proxy definition. Where no single parameter has indicatively been found to effectively represent fine sediment deposition in the investigated mountain catchment sinks (lakes and peat), use of multiple regression and principal compoent/canonical correspondance analysis (PCA/CCA) is implemented to identiy key forcing parameters. The correlation and statistical analysis initially undertaken is the first step towards long-term sediment transport modelling to represent alpine catchment runoff and erosion over the Holocene time period, with the potential to consider future long-term or rapid climate change impacts on the mountain critical zone.

Published
2017

48. Effects of soil redox potential (Eh) and pH on growth of sunflower and wheat.

Author

Cottes, Jérémy, Saquet, Alix, Palayret, Ludovic, Husson, Olivier, Beghin, Robin, Allen, Deonie, Scheiner, Javier, Cabanes, Cédric, and Guiresse, Maritxu

Subjects
REDUCTION potential, WHEAT, SOILS, PLANT growth, SUNFLOWER seeds, TIME measurements, SUNFLOWERS
Abstract

Soil redox potential (Eh) and pH are fundamentals parameters for plants growth. Measuring soil Eh is essential but complex due to the lack of measurement reliability resulting from high temporal variability and metrological challenges. This paper proposes practical advancements for measuring Eh in aerobic soils using combined electrodes (improvements in methodology specific to cleaning electrodes, measurement time, cleaning the dataset). The study of soil Eh and pH on sunflower and wheat in pot experiments has highlighted the relationship between Ehcumul (Eh associated with a dimension of time) and the portion of porosity that is accessible to air. For reduced soil conditions, sunflower positively reacts to better aeration. Strong correlations exist between the duration of each potential range and the growth of sunflower. The study of sunflower growth in soil reveals extremely harmful impact resulting from too high and/or too low Eh values. [ABSTRACT FROM AUTHOR]

Published
2020
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