Abstract. Since 70 % of global forests are managed and forests impact the global carbon cycle and the energy exchange with the overlying atmosphere, forest management has the potential to mitigate climate change. Yet, none of the land-surface models used in Earth system models, and therefore none of today's predictions of future climate, accounts for the interactions between climate and forest management. We addressed this gap in modelling capability by developing and parametrising a version of the ORCHIDEE land-surface model to simulate the biogeochemical and biophysical effects of forest management. The most significant changes between the new branch called ORCHIDEE-CAN (SVN r2290) and the trunk version of ORCHIDEE (SVN r2243) are the allometric-based allocation of carbon to leaf, root, wood, fruit and reserve pools; the transmittance, absorbance and reflectance of radiation within the canopy; and the vertical discretisation of the energy budget calculations. In addition, conceptual changes were introduced towards a better process representation for the interaction of radiation with snow, the hydraulic architecture of plants, the representation of forest management and a numerical solution for the photosynthesis formalism of Farquhar, von Caemmerer and Berry. For consistency reasons, these changes were extensively linked throughout the code. Parametrisation was revisited after introducing 12 new parameter sets that represent specific tree species or genera rather than a group of often distantly related or even unrelated species, as is the case in widely used plant functional types. Performance of the new model was compared against the trunk and validated against independent spatially explicit data for basal area, tree height, canopy structure, gross primary production (GPP), albedo and evapotranspiration over Europe. For all tested variables, Published by Copernicus Publications on behalf of the European Geosciences Union. K. Naudts et al.: A vertically discretised canopy description for ORCHIDEEORCHIDEE-CAN outperformed the trunk regarding its ability to reproduce large-scale spatial patterns as well as their inter-annual variability over Europe. Depending on the data stream, ORCHIDEE-CAN had a 67 to 92 % chance to reproduce the spatial and temporal variability of the validation data.

Spatial self‐organisation of ecosystems is the process by which large‐scale ordered spatial patterns emerge from disordered initial conditions through local feedbacks between organisms and their environment. Such process is considered important for ecosystem functioning, providing increased productivity, resistance and resilience against environmental change. Although spatial self‐organisation has been found for an increasing number of ecosystems, it has never been shown so far for aquatic river vegetation. Here we explore the existence of spatial self‐organisation of freshwater macrophyte patches in a typical lowland river (Belgium), showing that the underlying mechanisms for pattern formation are scale‐dependent feedbacks between plant growth, water flow and local river bed erosion and sedimentation. The mapping of vegetation patches showed that the frequency distribution of patch sizes is governed by a power‐law function, suggesting that the patches are self‐organised. Scale‐dependent feedbacks, likely to lead to this self‐organised pattern, were demonstrated with a mimic experiment. Both positive and negative feedbacks on plants were confirmed by a transplantation experiment. Placing vegetation patch mimics in the river showed experimentally that on a short range (within and behind the mimics) flow reduction and increased sedimentation occurred, while on a larger range (next to patches) the flow was accelerated and decreased sedimentation took place. By transplanting macrophytes within, next to and further away from existing patches, it was proven that the conditions within the patches favoured the survival and growth of transplants (i.e. short‐range positive feedback), while the conditions just next to patches led to decreased survival and growth (i.e. long‐range negative feedback).

Summary• Climate manipulation experiments are of key importance in identifying possible responses of plant communities and ecosystems to climate change. Experiments for warming the air under sunlit conditions are carried out in (partial) enclosures. These inevitably alter the energy balance inside, potentially altering tissue temperatures which affect metabolism and growth.• Using an empirically validated energy balance model, we investigate effects of two widely used warming methods, climate-controlled glasshouses and passively warmed open-top chambers (OTCs), on leaf temperatures. The model applies standard energy balance formulas, supplemented with data on optical properties of glasshouse materials and wind conditions inside OTCs.• Results show that the different radiation environment inside glasshouses did not produce large leaf temperature deviations compared with outside. Poor glasshouse design with significant radiation blockage by the structure or with insufficient ventilation did affect tissue temperatures more significantly. The drastic wind speed reduction inside OTCs approximately doubled the actual (canopy) warming compared with earlier reported increases in air temperature provided by this technique -an effect that was inflated if the plants' stomates closed.• These results demonstrate that leaf temperatures were higher than previously considered in OTCs but not in climate-controlled glasshouses.

Abstract. Since 70% of global forests are managed and forests impact the global carbon cycle and the energy exchange with the overlying atmosphere, forest management has the potential to mitigate climate change. Yet, none of the land surface models used in Earth system models, and therefore none of today's predictions of future climate, account for the interactions between climate and forest management. We addressed this gap in modelling capability by developing and parametrizing a version of the land surface model ORCHIDEE to simulate the biogeochemical and biophysical effects of forest management. The most significant changes between the new branch called ORCHIDEE-CAN (SVN r2290) and the trunk version of ORCHIDEE (SVN r2243) are the allometric-based allocation of carbon to leaf, root, wood, fruit and reserve pools; the transmittance, absorbance and reflectance of radiation within the canopy; and the vertical discretisation of the energy budget calculations. In addition, conceptual changes towards a~better process representation occurred for the interaction of radiation with snow, the hydraulic architecture of plants, the representation of forest management and a~numerical solution for the photosynthesis formalism of Farquhar, von Caemmerer and Berry. For consistency reasons, these changes were extensively linked throughout the code. Parametrization was revisited after introducing twelve new parameter sets that represent specific tree species or genera rather than a group of unrelated species, as is the case in widely used plant functional types. Performance of the new model was compared against the trunk and validated against independent spatially explicit data for basal area, tree height, canopy strucure, GPP, albedo and evapotranspiration over Europe. For all tested variables ORCHIDEE-CAN outperformed the trunk regarding its ability to reproduce large-scale spatial patterns as well as their inter-annual variability over Europe. Depending on the data stream, ORCHIDEE-CAN had a 67 to 92% chance to reproduce the spatial and temporal variability of the validation data.