Emissions of volatile organic compounds from aboveground and belowground parts of rapeseed (Brassica napus L.) and tomato (Solanum lycopersicum L.).

Root systems represent a source of Volatile Organic Compounds (VOCs) that may significantly contribute to the atmospheric VOC emissions from agroecosystems and shape soil microbial activity. To gain deeper insights into the role of roots in the VOC emissions from crops, we developed a dynamic chamber with isolated aboveground and belowground compartments, allowing for simultaneous measurements of VOC fluxes from both compartments in controlled conditions. We continuously monitored VOC emissions from intact plants of rapeseed (Brassica napus L.

Current controversies on mechanisms controlling soil carbon storage: implications for interactions with practitioners and policy-makers. A review.

There is currently an intense debate about the potential for additional organic carbon storage in soil, the strategies by which it may be accomplished and what the actual benefits might be for agriculture and the climate. Controversy forms an essential part of the scientific process, but on the topic of soil carbon storage, it may confuse the agricultural community and the general public and may delay actions to fight climate change. In an attempt to shed light on this topic, the originality of this article lies in its intention to provide a balanced description of contradictory scientific opinions on soil carbon storage and to examine how the scientific community can support decision-making despite the controversy.

Can N O emissions offset the benefits from soil organic carbon storage?

To respect the Paris agreement targeting a limitation of global warming below 2°C by 2100, and possibly below 1.5°C, drastic reductions of greenhouse gas emissions are mandatory but not sufficient. Large-scale deployment of other climate mitigation strategies is also necessary.

Biochar-assisted phytoextraction of Cd and Zn by Noccaea caerulescens on a contaminated soil: A four-year lysimeter study.

Amendments of biochar, the residual solid of biomass pyrolysis, have been shown to enhance metal phytoextraction from contaminated soils with hyperaccumulating plants in specific situations. In order to investigate this phenomenon over successive harvests in field conditions, two identical undisturbed soil cylinders (1-m section × 1.85-m height) were excavated from a contaminated agricultural plot and monitored with instrumented lysimeters.

Metal Immobilization on Wood-Derived Biochars: Distribution and Reactivity of Carbonate Phases.

Metals can be immobilized on biochars by precipitation with carbonate. The distribution of metal-carbonate phases at the surface of biochars and the conditions of their formation, however, are unknown. Electron microscopy and X-photon spectroscopy were used to characterize carbonate phases in various morphological groups of particles of a wood-derived biochar, both before and after a metal-sorption experiment.

Decrease in the genotoxicity of metal-contaminated soils with biochar amendments.

Biochar amendments, i.e., the solid product of biomass pyrolysis, reduce soil metal availability, which may lower the toxicity of metal-contaminated soils.

Metal immobilization by sludge-derived biochar: roles of mineral oxides and carbonized organic compartment.

Pyrolyzing sludge into biochar is a potentially promising recycling/disposal solution for municipal wastewater sludge, and the sludge-derived biochar (SDBC) presents an excellent sorbent for metal immobilization. As SDBC is composed of both mineral oxides and carbonized organic compartment, this study therefore compared the sorption behaviour of Pb and Zn on SDBC to those of individual and mixture of activated carbon (AC) and amorphous aluminium oxide (AlO). Batch experiments were conducted at 25 and 45 °C, and the metal-loaded sorbents were artificially aged in the atmosphere for 1-60 days followed by additional sorption experiments.

Toward the Standardization of Biochar Analysis: The COST Action TD1107 Interlaboratory Comparison.

Biochar produced by pyrolysis of organic residues is increasingly used for soil amendment and many other applications. However, analytical methods for its physical and chemical characterization are yet far from being specifically adapted, optimized, and standardized. Therefore, COST Action TD1107 conducted an interlaboratory comparison in which 22 laboratories from 12 countries analyzed three different types of biochar for 38 physical-chemical parameters (macro- and microelements, heavy metals, polycyclic aromatic hydrocarbons, pH, electrical conductivity, and specific surface area) with their preferential methods.

Root development of non-accumulating and hyperaccumulating plants in metal-contaminated soils amended with biochar.

Biochar may be used as an amendment in contaminated soils in phytoremediation processes. The mechanisms controlling plant metal uptake in biochar-amended soils remain however unclear. This work aimed at evaluating the influence of biochar on root development and its consequence on plant metal uptake, for two non-hyperaccumulating plants (Zea mays and Lolium perenne) and one hyperaccumulator of Cd and Zn (Noccaea caerulescens).