Integrated analysis of the detoxification responses of two Euramerican poplar genotypes exposed to ozone and water deficit: Focus on the ascorbate-glutathione cycle.

Ozone (O) and drought increase tree oxidative stress. To protect forest health, we need to improve risk assessment, using metric model such as the phytotoxic O dose above a threshold of y nmol·m·s (PODy), while taking into account detoxification mechanisms and interacting stresses. The impact of drought events on the effect of O pollution deserves special attention.

Biotic and abiotic experimental identification of bacterial influence on calcium isotopic signatures.

In this study, we tested experimentally the influence of plant and bacterial activities on the calcium (Ca) isotope distribution between soil solutions and plant organs. Abiotic apatite weathering experiments were performed under two different pH conditions using mineral and organic acids. Biotic experiments were performed using either apatite or Ca-enriched biotite substrates in the presence of Scots pines, inoculated or not with the rhizosphere bacterial strain Bulkholderia glathei PML1(12), or the B.

Bacterial weathering and its contribution to nutrient cycling in temperate forest ecosystems.

Unlike farmland, forests growing on acidic soils are among the terrestrial ecosystems that are the least influenced or amended by man. Forests which developed on acidic soils are characterized by an important stock of inorganic nutrients entrapped in poorly weatherable soil minerals. In this context, the mineral-weathering process is of great importance, since such minerals are not easily accessible to tree roots.