Rest-grazing before soil thawing alters the below-ground distribution and extent of rooting in Carex subalpine meadows

Livestock activities impact plant rhizomes and roots in the topsoil, particularly in the early stages of spring for a Carex subalpine meadow. Rest-grazing during critical periods can prevent harm to these roots and rhizomes caused by livestock, thereby enhancing the ecological performance of grasslands. In accordance with soil thawing and plant re-greening, we designated five rest-grazing periods during the spring in a Carex subalpine meadows. The findings demonstrate that the topsoil of 0-10 cm, largely consisting of Carex roots, housed over 70% of root volume and root mass. After the plant had regained its greenery for a certain duration, rest-grazing resulted in higher vertical root length distribution index. With earlier rest-grazing, root growth in deeper soil was promoted, consequently transporting more organic material to the deeper soil. Deferred rest-grazing time has the potential to enhance lateral rooting extent, root resistance to vertical uprooting, and root accumulation in topsoil. It follows that increased root accumulation in the topsoil leads to greater loss of soil nutrients and carbon. Consequently, we recommend rest-grazing prior to soil thawing for Carex subalpine meadows, which encourages Carex root growth and fosters greater biomass accumulation in deeper soils. Avoiding "running for the green" and "trampling tillage" has a positive effect on both productivity and long-term soil nutrients and carbon pool management in pastures.