Post-burning responses by vegetation on blanket bog peatland sites on a Scottish grouse moor

Abstract

Burning of ericaceous vegetation on moorland in the United Kingdom is a routine part of management for red grouse (Lagopus lagopus scotica) but its contribution to peatland degradation and loss of key ecosystem services is widely debated. Studies in the North Pennines, northern England, have shown that regular fires at approximately ten-year intervals can benefit Sphagnum mosses and cotton grass (Eriophorum) cover at the expense of ling heather (Calluna vulgaris). We repeated an assessment from a Pennine study of post-burning vegetation succession at a moor in south-west Scotland also managed for grouse. Here, GPS-mapped fires from 2009 to 14 were visited in 2019 to measure the vegetation response and compare it with unburned control plots. Heather cover, vegetation height and biomass increased linearly over time since burning, whereas cotton grass decreased during the first eight years. Sphagnum cover in plots burnt eight to ten years earlier averaged five times higher than that in the no-burn control plots and was positively correlated with peat depth. These results support earlier studies in northern England, showing that prescribed burning at regular intervals can increase Sphagnum cover by reducing heather cover and canopy vegetation biomass. We discuss the repercussions of this for management of blanket peat habitat, including reducing wildfire risk across UK moorlands.

Keywords

• Grouse moor
• Blanket peat
• Burning
• Sphagnum
• Remote sensing