Research team including Göttingen University identifies limit based on microbiology functions
The Tibetan plateau is of particular importance for a number of reasons: as a grazing ecosystem, as a carbon store, to initiate the monsoon climate, and to ensure a supply of drinking water. With low to moderate grazing, dead and living roots of the wild sedge plants that are widespread there protect the soil from degradation, meaning the gradual loss of ecosystem functions due to erosion. An international research team led by the Universities of Kiel, Göttingen and Hannover has now identified for the first time on a microbiological basis the critical threshold of grazing. Going past this point results in irreversible degradation. The results were published .
In the course of increasing degradation, the microbiome composition of the soil changes greatly. "At first, it-s just the residues of root system that can be easily degraded that are hydrolytically degraded. Then a stage follows characterised by an abrupt switch to the dominance of oxidising enzymes," says one of the two first authors Andreas Breidenbach from the Department of Biogeochemistry of Agroecosystems at Göttingen University. "At this -point of no return-, stabilising root residues are so completely degraded that erosion then increases significantly and the remaining topsoil is completely removed."
Original publication: Andreas Breidenbach et al., Microbial functional changes mark irreversible course of Tibetan grassland degradation, Nature Communications, https://doi.org/10.1038/s41467’022 -30047-7