TY - GEN A1 - Küppers, Manfred A1 - Schmitt, Dieter A1 - Liner, Susanne A1 - Böhm, Christian A1 - Kanzler, Michael A1 - Veste, Maik T1 - Photosynthetic characteristics and simulation of annual leaf carbon gains of hybrid poplar (Populus nigra L. x P. maximowiczii Henry) and black locust (Robinia pseudoacacia L.) in a temperate agroforestry system T2 - Agroforestry Systems N2 - A leaf net photosynthesis model is presented driven by light and modulated by temperature and air humidity. From this the seasonal variation of CO2 uptake and release could be modelled to estimate the annual carbon fluxes of sun and shade leaves. In fully expanded leaves light is the major factor determining daily carbon balances, and highest observed daily carbon gains in sun leaves amounted to 748.9 mmol CO2 m-2 day-1 in poplar and to 536.3 mmol CO2 m-2 day-1 in black locust, while the annual carbon gains amounted to 46,824 mol CO2 m-2 in black locust and 66,803 mol CO2 m-2 in hybrid poplar. Results obtained via gas exchange measurements and from the leaf model clearly indicate a potentially better growth performance of the poplar compared to black locust on the investigated site. The presented photosynthesis model provides a good and realistic estimation for seasonal carbon balances on the leaf level for both species. Y1 - 2018 U6 - https://doi.org/10.1007/s10457-017-0071-z SN - 0167-4366 SN - 1572-9680 VL - 92 IS - 5 SP - 1267 EP - 1286 ER -