Purpose We evaluated the importance of dry season (summer) sunlight on carbon (C) turnover in a Mediterranean-type climate ecosystem in the context of spatially heterogenous distribution of vegetation. Methods We manipulated summer sunlight exposure of litter and soil at the ecosystem scale in a natural Patagonian woodland over two years and evaluated its effect on C turnover in litter and surface soil. We measured decomposition of standing dead litter of dominant grass and shrub species, changes in labile C pools in soil microsites with and without plant litter, and potential enzyme activity of litter and both soil microsites, evaluating seasonal and legacy effects of summer sunlight exposure. Results Summer sunlight exposure significantly increased standing litter decomposition for both shrub and grass litter (p