By Abbas Nazil
Upland sheep grazing plays a critical role in protecting stable soil carbon and may be essential for long-term climate mitigation, according to a new UK study that warns removing grazers could weaken carbon storage in grassland ecosystems.
Researchers from the University of Manchester examined 12 upland grassland sites stretching across an 800-kilometre south-to-north corridor from Dartmoor in southwest England to Glensaugh in Aberdeenshire, Scotland.
The team compared areas that had been ungrazed for more than a decade with nearby grasslands that had continued to support sheep grazing over the same period.
While ungrazed fields tended to accumulate larger amounts of short-lived carbon in plant material and surface litter, they consistently showed lower levels of long-lasting organic carbon stored within the soil.
This more durable form of carbon is bound to soil minerals and is considered far more resistant to decomposition caused by rising temperatures.
Lead author Dr Luhong Zhou explained that although removing grazing allows vegetation to build up above ground, it reduces the formation of mineral-protected soil carbon that provides long-term climate benefits.
The researchers linked this decline in stable soil carbon to shifts in plant communities that occur when sheep are removed from upland landscapes.
Co-author Dr Shangshi Liu cautioned against treating grazer removal as a universal climate solution, noting that not all carbon gains offer the same durability or long-term mitigation value.
The findings come as governments review land-use strategies to meet net-zero targets, with upland grasslands covering vast areas of the UK and playing a significant role in national carbon budgets.
Professor Richard Bardgett of Lancaster University, who initiated the research, said maintaining low-intensity grazing appears vital for safeguarding the most resilient forms of soil carbon in these ecosystems.
He stressed that careful livestock management, rather than blanket grazing bans, could better support both environmental health and climate goals.
The National Sheep Association also welcomed the research, saying it highlights alternative approaches to emissions reduction that deserve greater attention in future environmental policy.
Chief executive Phil Stocker said the evidence suggests balanced land management strategies can protect carbon stores while sustaining rural livelihoods.
The study challenges assumptions that removing livestock automatically benefits the climate and points instead to the ecological value of traditional grazing in maintaining long-term soil carbon stability.