Configuring tree planting and forest restoration for climate adaptation

Climate warming can threaten biodiversity and trigger warming-related disturbances. Increasing tree cover in a landscape is recognized as a measure for cooling and moisture retention under certain conditions, but the role of its configuration-the spatial pattern of tree cover for a given amount-remains poorly understood. Building on recent evidence, we propose that the configuration of planted trees or restored forest in the landscape can influence the effectiveness of warming adaptation measures. We hypothesize that planting trees or restoring forests in a more fragmented configuration increases microclimatic refugia, reduces warming exposure for open- and edge-habitat species, and limits warming-related disturbances. We also hypothesize that a less fragmented configuration creates fewer but cooler microclimatic refugia and mitigates negative warming effects on patch-interior species.