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Franck Gilbert - One of the best experts on this subject based on the ideXlab platform.

  • Bioturbation effects on bioaccumulation of cadmium in the wetland plant Typha latifolia: A nature-based experiment
    Science of the Total Environment, 2018
    Co-Authors: Trung Kien Hoang, Franck Gilbert, Anne Probst, Didier Orange, Arnaud Elger, Jean Kallerhoff, Francois Laurent, Sabina Bassil, Thi Thuy Duong, Magali Gérino
    Abstract:

    The development of efficient bioremediation techniques to reduce aquatic pollutant load in natural sediment is one of the current challenges in ecological engineering. A nature-based solution for metal bioremediation is proposed through a combination of Bioturbation and phytoremediation processes in experimental indoor microcosms. The invertebrates Tubifex tubifex (Oligochaeta Tubificidae) was used as an active ecological engineer for Bioturbation enhancement. The riparian plant species Typha latifolia was selected for its efficiency in phyto-accumulating pollutants from sediment. Phytoremediation efficiency was estimated by using cadmium as a conservative pollutant known to bio-accumulate in plants, and initially introduced in the overlying water (20 μg Cd/L of cadmium nitrate – Cd(NO3)2·4H2O). Biological sediment reworking by invertebrates' activity was quantified using luminophores (inert particulates). Our results showed that Bioturbation caused by tubificid worms' activity followed the bio-conveying transport model with a downward vertical velocity (V) of luminophores ranging from 16.7 ± 4.5 to 18.5 ± 3.9 cm·year− 1. The biotransport changed the granulometric properties of the surface sediments, and this natural process was still efficient under cadmium contamination. The highest value of Cd enrichment coefficient for plant roots was observed in subsurface sediment layer (below 1 cm to 5 cm depth) with tubificids addition. We demonstrated that biotransport changed the distribution of cadmium across the sediment column as well as it enhanced the pumping of this metal from the surface to the anoxic sediment layers, thereby increasing the bioaccumulation of cadmium in the root system of Typha latifolia. This therefore highlights the potential of Bioturbation as a tool to be considered in future as integrated bioremediation strategies of metallic polluted sediment in aquatic ecosystems.

  • Impact of Oil on Bacterial Community Structure in Bioturbated Sediments
    2016
    Co-Authors: Magalie Stauffert, Franck Gilbert, Georges Stora, Cristiana Cravo-laureau, Ra Barantal, Christine Cagnon, David Amouroux, Fatima Mahdaoui, Brice Bouyssiere, Robert Duran
    Abstract:

    Oil spills threaten coastlines where biological processes supply essential ecosystem services. Therefore, it is crucial to understand how oil influences the microbial communities in sediments that play key roles in ecosystem functioning. Ecosystems such as sediments are characterized by intensive Bioturbation due to burrowing macrofauna that may modify the microbial metabolisms. It is thus essential to consider the Bioturbation when determining the impact of oil on microbial communities. In this study, an experimental laboratory device maintaining pristine collected mudflat sediments in microcosms closer to true environmental conditions – with tidal cycles and natural seawater – was used to simulate an oil spill under Bioturbation conditions. Different conditions were applied to the microcosms including an addition of: standardized oil (Blend Arabian Light crude oil, 25.6 mg.g21 wet sediment), the common burrowing organism Hediste (Nereis) diversicolor and both the oil and H. diversicolor. The addition of H. diversicolor and its associated Bioturbation did not affect the removal of petroleum hydrocarbons. After 270 days, 60 % of hydrocarbons had been removed in all microcosms irrespective of the H. diversicolor addition. However, 16S-rRNA gene and 16S-cDNA T-RFLP and RT-PCR-amplicon librarie

  • Quantification of sediment reworking by the Asiatic clam Corbicula fluminea Müller, 1774
    Hydrobiologia, 2014
    Co-Authors: Nabil Majdi, Léa Bardon, Franck Gilbert
    Abstract:

    Active organisms modify the substratum in which they dwell. This process, called "Bioturbation", affects the way that biogeochemical fluxes are mediated at the substratum-water interface. In the frame of this work, the Bioturbation potential of the Asiatic clam Corbicula fluminea was characterized and quantified. We measured the displacement of fluorescent particles by C. fluminea burying in a size-based experimental design in order to explore the effects of body-size on sediment reworking. Our results stress that C. fluminea belongs to the functional group of biodiffusors, and that C. fluminea can be considered as an intermediate sediment reworker. We suggest that Bioturbation was mainly induced by the pedal-feeding activity of the clams. Results also showed that, though large clams induced displacement of particles deeper into the sediment, small clams showed the highest net sediment reworking activity. This result was in contrast to the initial hypothesis of biovolume as the main driver for particle displacement by bioturbating organisms. Life-history traits and specific features of pedal-feeding could explain the observed pattern.

  • Impact of oil on bacterial community structure in bioturbated sediments
    PLoS ONE, 2013
    Co-Authors: Magalie Stauffert, Franck Gilbert, Cristiana Cravo-laureau, Christine Cagnon, David Amouroux, Ronan Jezequel, Sandra Barantal, Philippe Cuny, Cécile Militon, Fatima Mahdaoui
    Abstract:

    Oil spills threaten coastlines where biological processes supply essential ecosystem services. Therefore, it is crucial to understand how oil influences the microbial communities in sediments that play key roles in ecosystem functioning. Ecosystems such as sediments are characterized by intensive Bioturbation due to burrowing macrofauna that may modify the microbial metabolisms. It is thus essential to consider the Bioturbation when determining the impact of oil on microbial communities. In this study, an experimental laboratory device maintaining pristine collected mudflat sediments in microcosms closer to true environmental conditions - with tidal cycles and natural seawater - was used to simulate an oil spill under Bioturbation conditions. Different conditions were applied to the microcosms including an addition of: standardized oil (Blend Arabian Light crude oil, 25.6 mg.g21 wet sediment), the common burrowing organism Hediste (Nereis) diversicolor and both the oil and H. diversicolor. The addition of H. diversicolor and its associated Bioturbation did not affect the removal of petroleum hydrocarbons. After 270 days, 60% of hydrocarbons had been removed in all microcosms irrespective of the H. diversicolor addition. However, 16S-rRNA gene and 16S-cDNA T-RFLP and RT-PCR-amplicon libraries analysis showed an effect of the condition on the bacterial community structure, composition, and dynamics, supported by PerMANOVA analysis. The 16S-cDNA libraries from microcosms where H. diversicolor was added (oiled and un-oiled) showed a marked dominance of sequences related to Gammaproteobacteria. However, in the oiled-library sequences associated to Deltaproteobacteria and Bacteroidetes were also highly represented. The 16S-cDNA libraries from oiled-microcosms (with and without H. diversicolor addition) revealed two distinct microbial communities characterized by different phylotypes associated to known hydrocarbonoclastic bacteria and dominated by Gammaproteobacteria and Deltaproteobacteria. In the oiled-microcosms, the addition of H. diversicolor reduced the phylotype-richness, sequences associated to Actinobacteria, Firmicutes and Plantomycetes were not detected. These observations highlight the influence of the Bioturbation on the bacterial community structure without affecting the biodegradation capacities.

  • Influence of Chironomus riparius (Diptera, Chironomidae) and Tubifex tubifex (Annelida, Oligochaeta) on oxygen uptake by sediments. Consequences of uranium contamination
    Environmental pollution (Barking Essex : 1987), 2009
    Co-Authors: Sandra Lagauzere, Franck Gilbert, Georges Stora, Philippe Cuny, Laura Pischedda, Jean Marc Bonzom
    Abstract:

    The diffusive oxygen uptake (DOU) of sediments inhabited by Chironomus riparius and Tubifex tubifex was investigated using a planar oxygen optode device, and complemented by measurements of Bioturbation activity. Additional experiments were performed within contaminated sediments to assess the impact of uranium on these processes. After 72 h, the two invertebrate species significantly increased the DOU of sediments (13–14%), and no temporal variation occurred afterwards. Within contaminated sediments, it was already 24% higher before the introduction of the organisms, suggesting that uranium modified the sediment biogeochemistry. Although the two species firstly reacted by avoidance of contaminated sediment, they finally colonized it. Their Bioturbation activity was reduced but, for T. tubifex, it remained sufficient to induce a release of uranium to the water column and an increase of the DOU (53%). These results highlight the necessity of further investigations to take into account the interactions between Bioturbation, microbial metabolism and pollutants.

Bo Li - One of the best experts on this subject based on the ideXlab platform.

  • Bioturbation of burrowing crabs promotes sediment turnover and carbon and nitrogen movements in an estuarine salt marsh
    Ecosystems, 2010
    Co-Authors: Jin Qing Wang, Chang Ming Fang, Mark D Bertness, Lifen Jiang, Toshihiko Hara, Bo Li, Jiakuan Chen, Xiaodong Zhang
    Abstract:

    Ecological functions of Bioturbation in ecosystems have received increasing attention over the recent decades, and crab burrowing has been considered as one of the major Bioturbations affecting the physical and chemical processes in salt marshes. This study assessed the integrated effects of crab excavating and burrow mimic trapping on sediment turnover and vertical C and N distributions in a Chinese salt marsh in the Yangtze River estuary. Crab burrowing increased soil water content and the turnover of carbon and nitrogen and decreased bulk soil density. Vertical movement of materials, nutrient cycling and reuse driven by crab burrowing might be obstructed by vegetation (Phragmitesaustralis and Spartinaalterniflora communities). The amount of soil excavated by crab burrowing was higher than that deposited into burrow mimics. In Phragmites marshes, Spartina marshes and unvegetated mudflats, net transport of soil to the marsh surface was 171.73, 109.54, and 374.95 g m−2 d−1, respectively; and the corresponding estimated soil turnover time was 2.89, 4.07 and 1.83 years, respectively. Crab burrowing in salt marshes can mix surface and deeper soil over a period of years, accelerating litter decomposition and promoting the efficient reuse of nutrients by plants. Therefore, Bioturbation affects soil physical processes and functioning of ecosystems, and needs to be addressed in ecosystem management.

Femke H. Tonneijck - One of the best experts on this subject based on the ideXlab platform.

  • UvA-DARE (Digital Academic Repository) The influence of Bioturbation on the vertical distribution of soil organic matter in volcanic ash soils: a case study in northern Ecuador
    2020
    Co-Authors: Femke H. Tonneijck
    Abstract:

    Summary Soil faunal Bioturbation ('Bioturbation') is often cited as a major process influencing the vertical distribution of soil organic matter (SOM). The influence of Bioturbation on vertical SOM transport is complex because it is the result of interaction between different groups of soil faunal species that redistribute SOM through the soil profile in distinct ways. We performed a semi-quantitative micromorphological analysis of soil faunal pedofeatures and related their occurrence to the vertical distribution of SOM and highresolution radiocarbon dating in volcanic ash soils under montane forest and grassland (pa´ramo) vegetation in the northern Ecuadorian Andes. The pa´ramo soil data suggest that Bioturbation was largely responsible for the vertical distribution of SOM, while illuviation and root input were of minor importance. Bioturbation was caused by endogeic species, which typically mix the soil only over short vertical distances. Short vertical distance mixing was apparently enhanced by the upward shifting of Bioturbation as a result of soil thickening due to SOM accumulation. A change from pa´ramo to forest vegetation was accompanied by a change from endogeic to epigeic species. As these latter species do not redistribute material vertically, this eventually resulted in the formation of thick ectorganic horizons in the forest

  • The effect of change in soil volume on organic matter distribution in a volcanic ash soil
    European Journal of Soil Science, 2016
    Co-Authors: Femke H. Tonneijck, M. Velthuis, Willem Bouten, E.e. Van Loon, Jan Sevink, Jacobus M. Verstraten
    Abstract:

    Volcanic ash soil contains large stocks of organic matter per unit area. A large proportion of organic matter is stored in the subsoil; therefore, a thorough understanding of its vertical distribution is needed to predict the effects of change in climate and land use. Faunal Bioturbation is often cited as the dominant process that affects the vertical distribution of organic matter. An additional but often overlooked process is change in the volume of the soil. Such change might affect the vertical distribution of organic matter by changing the position of the soil surface, which can affect the soil-forming processes related to depth, such as weathering, decomposition, Bioturbation and rooting. We calculated the change in volume with geochemical mass balance equations, and showed the effect of change in soil volume on the vertical distribution of organic matter using a dynamic model. Then we evaluated the plausibility of the model concept with an independent model for parameter identification and through a model sensitivity analysis. Results show that volume change is a major soil-forming process that determines the vertical distribution of organic matter in volcanic ash soil as the active Bioturbation zone moves upwards in response to soil thickening.

  • the influence of Bioturbation on the vertical distribution of soil organic matter in volcanic ash soils a case study in northern ecuador
    European Journal of Soil Science, 2008
    Co-Authors: Femke H. Tonneijck, A G Jongmans
    Abstract:

    Soil faunal Bioturbation ('Bioturbation') is often cited as a major process influencing the vertical distribution of soil organic matter (SOM). The influence of Bioturbation on vertical SOM transport is complex because it is the result of interaction between different groups of soil faunal species that redistribute SOM through the soil profile in distinct ways. We performed a semi-quantitative micromorphological analysis of soil faunal pedofeatures and related their occurrence to the vertical distribution of SOM and high-resolution radiocarbon dating in volcanic ash soils under montane forest and grassland (paramo) vegetation in the northern Ecuadorian Andes. The paramo soil data suggest that Bioturbation was largely responsible for the vertical distribution of SOM, while illuviation and root input were of minor importance. Bioturbation was caused by endogeic species, which typically mix the soil only over short vertical distances. Short vertical distance mixing was apparently enhanced by the upward shifting of Bioturbation as a result of soil thickening due to SOM accumulation. A change from paramo to forest vegetation was accompanied by a change from endogeic to epigeic species. As these latter species do not redistribute material vertically, this eventually resulted in the formation of thick ectorganic horizons in the forest.

Wenjia Deng - One of the best experts on this subject based on the ideXlab platform.

  • effects of chironomid larvae and limnodrilus hoffmeisteri Bioturbation on the distribution and flux of chromium at the sediment water interface
    Journal of Environmental Management, 2019
    Co-Authors: Dandong Cheng, Jinxi Song, Xiaotian Zhao, Shaoqing Wang, Qidong Lin, Jianglin Peng, Wenjia Deng
    Abstract:

    The impacts of chironomid larvae and the tubificid worm Limnodrilus hoffmeisteri on the distribution and flux of the heavy metal chromium (Cr) across the sediment-water interface were investigated with a 21-day laboratory microcosm experiment. The two studied species feature different Bioturbation modes involving bioirrigation and upward bioconveyance. The Cr concentrations in the overlying water and pore water were measured and compared using treatments with Bioturbation by a single species and by combinations of both species and a treatment with no organisms. The results indicated that both Bioturbation modes significantly increased the Cr concentrations in the overlying water and pore water. The overlying water had lower Cr concentrations than the pore water. Little variation in the Cr concentrations was observed in the treatment without organisms. Both species enhanced the Cr flux from the pore water to the overlying water. The worm treatments had a great impact on the Cr concentration in the overlying water through intensive upward conveyance activity, while the chironomid larvae treatments exerted significant effects on the Cr variation in the pore water and Cr flux across the interface via bioirrigation activity. These findings reveal the importance of Bioturbation in biogeochemical processes in freshwater ecosystems.

Dongsheng Wang - One of the best experts on this subject based on the ideXlab platform.

  • investigation of heavy metals release from sediment with Bioturbation bioirrigation
    Chemosphere, 2017
    Co-Authors: Bin Men, Xiaofang Yang, Dongsheng Wang
    Abstract:

    Bioturbation/bioirrigation can affect the remobilization of metals from sediments. In this study, experiments were performed to examine the effect of Bioturbation/bioirrigation by different organisms on cadmium (Cd), copper (Cu), zinc (Zn) and lead (Pb) releasing from the spiked sediment. The diffusive gradient in thin films technique (DGT) revealed that at the end of exposure time, the labile heavy metals concentrations in the pore water for all metal and organisms combinations except Cu and chironomid larvae were much lower than that in the control group. However, the concentrations of heavy metals detected by the DGT were virtually indistinguishable among the treatments with tubificid, chironomid larvae and loach. The correlation analysis of heavy metals with iron (Fe) and manganese (Mn) suggested that Cd, Zn and Pb were most likely bound as Fe-Mn oxidation form in the pore water, but Cu was in other forms. After 28 d of exposure, Bioturbation/bioirrigation produced a significant release of particulate heavy metals into the overlying water, especially in the treatment with loach. The Bioturbation/bioirrigation impact on the Pb remobilization was less than the other three heavy metals. The effects of bioturbaiton/bioirrigation on the heavy metals remobilization in the sediment were complex that with studying the heavy metals remobilization in the sediment and water interface, the biological indicators should be recommended.

  • Bioturbation bioirrigation effect on thallium released from reservoir sediment by different organism types
    Science of The Total Environment, 2015
    Co-Authors: Bin Men, Xiaofang Yang, Dongsheng Wang
    Abstract:

    Bioturbation can remobilize heavy metal in the sediments and may pose a risk for aquatic biota. The effects of Bioturbation/bioirrigation by three different riverine organism types (Tubificid, Chironomid larvae, and Loach) on thallium release from contaminated sediment (10.0 ± 1.1 mg Tl/kg sediment, dry wt.) were evaluated in this study. The Bioturbation by the epibenthos clearly caused an increased turbidity in the overlying water, and the effect was in the order of Loach > Chironomid larvae > Tubificid. A significant release of Tl into the water column via the resuspended sediment particles was observed, especially for Loach. During the first few days, the leaching of dissolved Tl from sediment into water was fast, and the dissolved Tl under Bioturbation/bioirrigation was much higher than the control group. However, after 14 days, the Bioturbation/bioirrigation process seemed to suppress the release of Tl from the sediment particles to water, especially for sediment with Loach. This may partly be due to the sorption or coprecipitation of Tl simultaneous with the formation of iron and manganese hydrous oxides with increased pH values as a consequence of phytoplankton growth. Linear regression analysis confirmed that both the total and particulate Tl concentrations had good correlations with particulate Fe and Mn concentrations as well as turbidity in the overlying water. Additionally, planktonic bacteria may oxidize the Tl(I) to Tl(III), resulting in a reduced solubility of Tl by which Tl(OH)3 becomes the predominant form of Tl.