Climate change is exposing terrestrial ecosystems to warmer temperatures, increased CO₂ levels, and more frequent and intense drought and rainfall events. How different ecosystems respond to changing climatic conditions depends on a multitude of biological and geochemical processes which interact at different temporal and spatial scales.

On the one hand, plants assimilate carbon from the atmosphere and control carbon inputs into soil via plant detritus and rhizodeposition. On the other hand, soil fauna and microorganisms govern the decomposition of plant detritus and soil organic matter, which determines the cycling of carbon and of the nutrients necessary for plant growth. These interactions are further shaped by local environmental properties, such as vegetation type, relief, soil mineralogy, and physical structure, as well as the composition of plants and soil biota. Since soils represent the largest stock of organic carbon in terrestrial ecosystems and regulate carbon fluxes for about 10 times the current anthropogenic emissions, changes in the above-mentioned processes can have strong implications for global carbon cycling. Furthermore, the understanding of soil functioning is critical for improving predictions on the resistance and resilience of terrestrial ecosystems to climate change.

In this special issue, we seek to highlight research on biotic and abiotic interactions underlying terrestrial biogeochemical responses to climate, with a specific emphasis on elevated atmospheric CO₂, warming, drought, and drying–rewetting events. We invite contributions covering field and laboratory experiments, conceptual development, and modelling studies.