Erik J. Joner
Head of Department/Head of Research
Biography
Abstract
Heavy metals in soil pose a constant risk for animals and humans when entering their food chains, and limited means are available to reduce plant accumulation from more or less polluted soils. Biochar, which is made by pyrolysis of organic residues and sees increasing use as a soil amendment to mitigate anthropogenic C emissions and improve agronomic soil properties, has also been shown to reduce plant availability of heavy metals in soils. The cause for the reduction of metal uptake in plants when grown in soils enriched with biochar has generally been researched in terms of increased pH and alkalinity, while other potential mechanisms have been less studied. We conducted a pot experiment with barley using three soils differing in metal content and amended or not with 2% biochar made from Miscanthus x giganteus, and assessed plant contents and changes in bioavailability in bulk and rhizosphere soil by measuring extractability in acetic acid or ammonium nitrate. In spite of negligible pH changes upon biochar amendment, the results showed that biochar reduced extractability of Cu, Pb and Zn, but not of Cd. Rhizosphere soil contained more easily extractable Cu, Pb and Zn than bulk soil, while for Cd it did not. Generally, reduced plant uptake due to biochar was reflected in the amounts of metals extractable with ammonium nitrate, but not acetic acid.
Abstract
We investigated dissipation, earthworm and plant accumulation of organic contaminants in soil amended with three types of sewage sludge in the presence and absence of plants. After 3 months, soil, plants and earthworms were analyzed for their content of organic contaminants. The results showed that the presence of plant roots did not affect dissipation rates, except for galaxolide. Transfer of galaxolide and triclosan to earthworms was significant, with transfer factors of 10–60 for galaxolide and 140–620 for triclosan in the presence of plants. In the absence of plants, transfer factors were 2–9 times higher. The reduced transfer to worms in the presence of plants was most likely due to roots serving as an alternative food source. Nonylphenol monoethoxylate rapidly dissipated in soil, but initial exposure resulted in uptake in worms, which was detected even 3 months after sewage sludge application. These values were higher than the soil concentration at the start of the exposure period. This indicates that a chemical's short half-life in soil is no guarantee that it poses a minimal environmental risk, as even short-term exposure may cause bioaccumulation and risks for chronic or even transgenerational effects.
Authors
Nanna B. Svenningsen Stephanie J Watts-Williams Erik J. Joner Fabio Battini Aikaterini Efthymiou Carla Cruz-Paredes Ole Nybroe Iver JakobsenAbstract
Arbuscular mycorrhizal fungi (AMF) colonise roots of most plants; their extra-radical mycelium (ERM) extends into the soil and acquires nutrients for the plant. The ERM coexists with soil microbial communities and it is unresolved whether these communities stimulate or suppress the ERM activity. This work studied the prevalence of suppressed ERM activity and identified main components behind the suppression. ERM activity was determined by quantifying ERM-mediated P uptake from radioisotope-labelled unsterile soil into plants, and compared to soil physicochemical characteristics and soil microbiome composition. ERM activity varied considerably and was greatly suppressed in 4 of 21 soils. Suppression was mitigated by soil pasteurisation and had a dominating biotic component. AMF-suppressive soils had high abundances of Acidobacteria, and other bacterial taxa being putative fungal antagonists. Suppression was also associated with low soil pH, but this effect was likely indirect, as the relative abundance of, e.g., Acidobacteria decreased after liming. Suppression could not be transferred by adding small amounts of suppressive soil to conducive soil, and thus appeared to involve the common action of several taxa. The presence of AMF antagonists resembles the phenomenon of disease-suppressive soils and implies that ecosystem services of AMF will depend strongly on the specific soil microbiome.
Authors
Erik J. JonerAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Gunhild Bødtker Claire Coutris Eva Marie-Louise Denison Åsa Frostegård Erik J. Joner Bjørn Tore Lunestad Elisabeth Henie Madslien Kaare Magne Nielsen Pål TrosvikAbstract
In this self-tasking scoping review, VKM will map research about the environmental impacts of biodegradable plastics, including biodegradation rates and material persistence in different environments and geographical regions, the influence on microbial ecology and activity, and ecotoxicological effects of materials and associated chemical substances. Related to this is also research associated with the development of methodology, standards, environmental risk assessment, life cycle impact analyses, material sources and properties of biodegradable plastics and products. The aim is to 1) determine the extent of evidence summarised in reviews and original research papers within this emerging research area and 2) map the evidence according to the materials and chemicals studied, types of environments and geographical regions covered, the hypotheses addressed, the type of endpoints assessed and the reported key findings. Systematic literature searches will be performed to identify the summarised evidence, applying APRIO to develop a tailored search protocol that addresses the multi- and cross-disciplinary nature of the research area. We will select and map the identified publications applying Rayyan and sort them into three categories based on their main scientific focus and aim of study: 1) material properties and application, 2) biodegradation and microbial ecology, and 3) ecotoxicology. There will be no geographical restrictions on the search and study selection, but in the data charting process we will highlight findings relevant to Norway and other Nordic countries. The current project adheres to the “Preferred Reporting Items for Systematic Reviews and MetaAnalyses extension for Scoping Reviews (PRISMA-ScR) Checklist” for protocol development and reporting. We will address uncertainties associated with research studies applying EFSA guidelines and their generic list of common types of uncertainty affecting scientific studies and assessments.
Division of Environment and Natural Resources
PROLAND – Protecting agricultural lands from plastic pollution
PROLAND addresses the sources of plastic pollution in agricultural soils: sewage sludge, compost, biogas digestate, agricultural plastics, and atmospheric deposition. The project unfolds pressures of plastic and associated chemical hazards by analyzing their levels in soils and conducting fate and impact studies. It deploys cutting edge “design thinking” methods to co-develop measures for pollution prevention.
Division of Environment and Natural Resources
PREPSOIL
PREPSOIL facilitates the implementation of Mission Soil in Europe. This is done through co-creating and launching tools and venues for communication and learning, as well as through mapping and dialogue to understand how regional soil needs assessments, supported by harmonized monitoring mechanisms, can lead to action in Living Labs and Lighthouses.
Division of Environment and Natural Resources
TerraNordica: Nordic Partnership for Soil Health and Agroecology
Soil health and Ecosystem Services (ES) are assessed through measuring carefully selected physical, chemical, and biological soil indicators related to dynamic soil properties, and compare these to thresholds or standard values that separate healthy from unhealthy conditions.