Changes over time in organic matter dynamics and copper solubility in a vineyard soil after incorporation of cover crop residues: Insights from a batch experiment.

Cover crops (CCs) are increasingly used in viticulture because they benefit the soil and the environment in many ways. This study investigated the extent to which the incorporation of CC residues altered organic matter (OM) and Cu dynamics in a Cu-contaminated vineyard topsoil. A 92-day incubation period was used to monitor changes over time in carbon mineralization, carbon hydrolytic enzyme activity, concentration and optical properties of dissolved organic matter (DOM), and Cu solubility after the addition (or not) of two CC residues, oat or faba bean.

Estimating the Acid-Base Properties and Electrical Charge of Organic Matter Using Spectrophotometry.

Spectrophotometric acid-base titration is a simple and powerful technique to evaluate the properties of proton binding sites of natural organic matter (NOM) at environmentally relevant concentrations. However, it is challenging to quantify the chemical charges () carried by NOM at these concentrations. Based on a previous work, which relates the variation of with the specific UV-vis differential absorbance (Δ) at a given wavelength (λ) and pH of a dissolved NOM sample, the present work proposes a method to investigate any NOM sample.

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.

Do DOM optical parameters improve the prediction of copper availability in vineyard soils?

Accumulation of copper (Cu) in soils due to the application of fungicides may be toxic for organisms and hence affect winegrowing sustainability. Soil parameters such as pH and dissolved organic matter (DOM) are known to affect the availability of Cu. In this study, we investigated the contribution of chromophoric and fluorescent DOM properties to the prediction of Cu availability in 18 organic vineyard soils in the Bordeaux winegrowing area (France).

Redox Controls over the Stability of U(IV) in Floodplains of the Upper Colorado River Basin.

Aquifers in the Upper Colorado River Basin (UCRB) exhibit persistent uranium (U) groundwater contamination plumes originating from former ore processing operations. Previous observations at Rifle, Colorado, have shown that fine grained, sulfidic, organic-enriched sediments accumulate U in its reduced form, U(IV), which is less mobile than oxidized U(VI). These reduced sediment bodies can subsequently act as secondary sources, releasing U back to the aquifer.