Mineral phosphate is a finite resource, so ways must be found to optimise the use of native soil P. We have used isotopic dilution to assess how acidification and the addition of citrate or oxalate modify the lability of soil P in four contrasting soils from the Mediterranean region. Acidification did not mobilise soil P, whereas both carboxylate anions promoted soil-P lability. This suggests that soil amendments and the choice of crops that exude carboxylates could optimise P nutrition.

Permafrost peatlands are large reservoirs of carbon. As frozen permafrost thaws, drier peat moisture conditions can arise, affecting the microbial production of climate-warming greenhouse gases like CO₂ and N₂O. Our study suggests that future peat CO₂ and N₂O production depends on whether drier peat plateaus thaw into wetter fens or bogs and on their diverging responses of peat respiration to more moisture-limited conditions.

To investigate how added nutrient nitrogen (N) and phosphorus (P) affect subarctic peatlands, we sampled peat soils from bog and fen type peatlands in the Northwest Territories, Canada, and measured CO₂ and CH₄ production rates by means of laboratory incubations. Our short-term experiments show that changes in nutrient concentrations in soil water can significantly affect microbial carbon cycling, suggesting the necessity of additional considerations of wildfire and permafrost thaw impacts on peatland carbon storage.

Here, we investigated how biochar, a potential C sequestration tool, affects early carbon storage in different soils. We created artificial soils to isolate the impact of soil texture. We found that biochar significantly reduces plant residue’s breakdown in all soil textures but mainly in sandy soils, which naturally hold less carbon. This suggests that biochar could be a valuable tool for improving soil health, especially in sandy soils.