Search results for "Soil contamination"

2021

Abstract Contaminated soils are lands in Europe deemed less favourable for conventional agriculture. To overcome the problem of their poor fertility, bio-fertilization could be a promising approach. Soil inoculation with a choice of biological species (e.g. earthworm, mycorrhizal fungi, diazotroph bacteria) can be performed in order to improve soil properties and promote nutrients recycling. However, questions arise concerning the dynamics of the contaminants in an inoculated soil. The aim of this study was to highlight the soil-plant-earthworm interactions in the case of a slightly contaminated soil. For this purpose, a pot experiment in controlled conditions was carried out during 2 month…

Anthropogenic lead distribution in soils under arable land and permanent grassland estimated by Pb isotopic compositions

2008

International audience; The role of land use on fate of metals in soils is poorly understood. In this work, we studied the incorporation of lead in two neighboring soils with comparable pedogenesis but under long-term different agricultural management. Distributions of anthropogenic Pb were assessed from concentrations and isotopic compositions determined on bulk horizon samples, systematical 5–10 cm increment samples, and on 24-h EDTA extracts. Minor amounts of anthropogenic lead were detected until 1-m depth under permanent grassland, linked to high earthworm activity. In arable land, exogenous Pb predominantly accumulated at depths <60 cm. Although the proximity between the two sites ens…

Evidence of organic contamination in urban soils of Cotonou town (Benin).

2012

14 pages; International audience; In Cotonou (Benin), growth of the population leads to an excessive use of natural resources, inducing organic contaminations. Surface soils collected in the town, were extracted and fractionated by liquid chromatography in three families: aliphatic, aromatic hydrocarbons and polar fractions. Each fraction was characterized by gas chromatography-mass spectrometry. All the results show that an anthropogenic input exists (waste oils). Indeed, aliphatic hydrocarbons have specific markers emphasizing the presence of petrogenic products: UCM (unresolved complex mixture), specific distribution of pentacyclic triterpane. However, specific molecular biomarkers revea…

The asexual enchytraeid worm Cognettia sphagnetorum (Oligochaeta) has increased Cu resistance in polluted soil

2001

We studied Cu resistance in the asexual (reproduction through fragmentation) enchytraeid worms (Cognettia sphagnetorum, Oligochaeta) originating from two sites: one uncontaminated, and another contaminated by heavy metals. Adult worms were smaller and population density was lower at the polluted site. However, adults from the contaminated site had better survival in Cu-contaminated soil, but lower survival as juveniles (fragments). As we do not know the genetic basis of Cu resistance of the worms, it may have been reached by acclimatization via induced Cu regulation. Because fragmentation is the only mode of reproduction, all phenotypic properties (including resistance) of a parental genera…

Life history and spatial distribution of the enchytraeid wormCognettia sphagnetorum(Oligochaeta) in metal-polluted soil: Below-ground sink-source pop…

2001

We studied the life history, metal-avoidance behavior, spatial distribution, and population growth of enchytraeid worms (Cognettia sphagnetorum [Oligochaeta]) originating from two sites: one uncontaminated, and another patchily polluted by heavy metals. Effects of patchy soil contamination on populations were studied in microcosms. In uncontaminated soil, worms from the polluted site had lower viability and reduced growth rate as juveniles but higher growth rate as adults compared to worms from the unpolluted site. They were also smaller in size at fragmentation (reproduction). Worms from the polluted site reached a larger population size than worms from the unpolluted site. Hence, worms fr…

Unconventional yeast in the degradation of hydrocarbons in contaminated soil

2018

The influence of Yarrowia lipolytica inoculum on biodegradation of hydrocarbons, and changes in microbiota composition in the soil contaminated with petroleum have been investigated. The material under study was contaminated clay soil, containing petroleum-derived substances at approximately 17 000 [mg/kg d. m.]. Microbiological analysis was carried out by the cultivation method and the content of individual hydrocarbons (n-aliphatic, BTEX and PAHs) was determined by the GC/MS method. The largest decrease of oil-derived substances, versus the control sample, was recorded at the beginning of the process. During the first 30 days, the yeast inoculation caused most effectively removal of n-ali…

Biostimulation proved to be the most efficient method in the comparison of in situ soil remediation treatments after a simulated oil spill accident

2016

The use of in situ techniques in soil remediation is still rare in Finland and most other European countries due to the uncertainty of the effectiveness of the techniques especially in cold regions and also due to their potential side effects on the environment. In this study, we compared the biostimulation, chemical oxidation, and natural attenuation treatments in natural conditions and pilot scale during a 16-month experiment. A real fuel spill accident was used as a model for experiment setup and soil contamination. We found that biostimulation significantly decreased the contaminant leachate into the water, including also the non-aqueous phase liquid (NAPL). The total NAPL leachate was …

Effects of Apirolio Addition and Alfalfa and Compost Treatments on the Natural Microbial Community of a Historically PCB-Contaminated Soil

2018

Abstract Polychlorinated biphenyls (PCBs) are ubiquitous and persistent organic pollutants generated exclusively from human sources and found in the environment as several congeners (e.g. Apirolio, produced in Italy and used for electrical transformers). To evaluate the ability of the natural microbial community of historically PCB-contaminated soil to transform or degrade PCBs after fresh contamination through the addition of Apirolio, a microcosm experiment was conducted in a greenhouse for approximately 8 months. Compost and Medicago sativa (alfalfa) were additionally used in the microcosms to stimulate microbial PCB degradation. Chemical analyses were performed to evaluate PCB concentra…

atzgene expressions during atrazine degradation in the soil drilosphere

2010

One of the various ecosystemic services sustained by soil is pollutant degradation mediated by adapted soil bacteria. The pathways of atrazine biodegradation have been elucidated but in situ expression of the genes involved in atrazine degradation has yet to be demonstrated in soil. Expression of the atzA and atzD genes involved in atrazine dechlorination and s-triazine ring cleavage, respectively, was investigated during in situ degradation of atrazine in the soil drilosphere and bulked samples from two agricultural soils that differed in their ability to mineralize atrazine. Interestingly, expression of the atzA gene, although present in both soils, was not detected. Atrazine mineralizati…

Poplar biomass production at phytomanagement sites is significantly enhanced by mycorrhizal inoculation

2017

Abstract Afforestation of trace element (TE)-contaminated soil, notably with fast growing trees producing large biomass has been demonstrated to be an attractive option for their bioremediation. Mycorrhizal fungi can form symbiotic associations with plants, contributing to TE tolerance and participating actively in bioremediation processes. We studied the effects of mycorrhizal inoculation on the growth of two poplar clones (Skado and I214), to large-scale. Two TE-contaminated sites of ca . 1 ha (Pierrelaye and Fresnes-sur-Escaut, France) were planted with 2200 trees, and were either inoculated with a mixed commercial inoculum or not-inoculated and allometric parameters were determined afte…