As an extension of the Atmosphere-Simulation Chamber SAPHIR, we developed an environmentally-controlled dynamic (flow-through) Plant Unit for Simulation (PLUS) chamber. This facility allows feeding a natural blend of biogenic trace gases into SAPHIR. Plants emit a vast number of individual volatile organic compounds (VOC). The emission strength and emission pattern depends on plant type and environmental conditions. The exact effects of climate change and associated stress conditions on VOC emissions are currently unknown. PLUS will be utilized to characterize the atmospheric chemistry of natural VOC mixtures at close to ambient concentration levels. Beside temperature control (panel heating/cooling), light control (LED panels), and soil water control (irrigation system), special emphasis is put on the use of inert non-emitting materials as inner surfaces of the chamber.
SAPHIR-PLUS will advance the capability to study the exchange of biogenic volatile compounds and their influence on the atmospheric oxidant cycle and secondary organic aerosols, among others.