The influence of system heterogeneity on peat-surface temperature dynamics

Abstract Temperatures at the soil–atmosphere interface influence ecosystem function by driving nonlinear terrestrial biogeochemical, ecohydrological, and micrometeorological processes. Whilst climate, soil vegetation controls on spatially average temperatures are recognised, how interacting heterogeneous layers create spatio-temporal complex thermal ecosystems has not been determined. Such hot spots moments may underpin capability of to support biological biogeochemical diversity control likelihood tipping points in system-regulating feedbacks being locally exceeded. This is notable importance peatlands, where storage their associated globally important carbon stocks. Here, through application high resolution surface temperature data peat modelling, we assess impact system heterogeneity (spatio-temporal following layers: tree, shrubs, microtopography, groundcover species sub-surface ice) regimes. We show (a) that peat-surface hotspot intensity longevity linked (b) all have an equal over regime extreme temperatures; increases up a maximum five decreases thereafter. The results crucially demonstrate such changes dynamics extremes occur without significant median temperatures. conceptual understanding peatland responses resilience disturbance. It emphasises need determine potential for transitions magnitude, locality small-scale induce functional propagate given ecosystems, characterise complexity scale ecohydrological function.