Effects of fire on the hydrology, biogeochemistry, and ecology of peatland river systems

AbstractPeatlands are found around the world and cover ∼3.4% of the Earth’s surface. In the UK, peatlands cover 17.2% or ∼1.58 Mha of the land surface and occur mainly in upland areas covering the headwaters of most major British rivers. However, large areas are now subject to prescribed vegetation burning despite policy guidance that recommends a strong presumption against burning on deep blanket peat. Wildfires occur sporadically but are forecast to increase in frequency in the future. This paper provides a synthesis of current knowledge about how UK peatland-dominated river catchments respond to fires caused by prescribed vegetation burning and uncontrolled wildfire. We provide insight into the effects of fire on the hydrology, biogeochemistry, and biota of peatland river ecosystems, and the peatland-soil-driven controls on these effects at the catchment scale. Burning increases the depth to water table and water-table variability, although some small-scale studies indicate shallower water table in som...