There are surprising grey areas in the precise quantification of pathways that produce nitrous oxide, a potent greenhouse gas, as influenced by soil moisture. Here, we take a new look at a classic study but use isotopomers as a powerful tool to determine the source pathways of nitrous oxide as regulated by soil moisture. Our results support earlier research, but we contribute scientific advancements by providing models that enable quantifying source partitioning rather than just inferencing.

Policy to conserve thinning arable soils relies on a balance between the rates of soil erosion and soil formation. Our knowledge of the latter is meagre. Here, we present soil formation rates for an arable hillslope, the first of their kind globally, and a woodland hillslope, the first of their kind in Europe. Rates range between 26 and 96 mm kyr⁻¹. On the arable site, erosion rates are 2 orders of magnitude greater, and in a worst-case scenario, bedrock exposure could occur in 212 years.

This paper is original research done in north-western Tunisia; it presents the impacts of the topography (slope and aspect) and the land use systems in the SOC storage in a Mediterranean area. It provides a soil spectral library, describes the variation of SOC under different conditions, and highlights the positive impact of agroforestry as good management in improving the SOC. Therefore this finding is very important to support decision making and inform sustainable land management in Tunisia.