The University of Bonn (UBO) is working in plant/atmosphere exchange, identifying and investigating fundamentals of aerosol impacts on plants. Our activities, e.g. within the ECLAIRE project, have taken this forward to a point where we could show that aerosols formed from NH3 can reduce the drought tolerance of plants, indicating a so far unknown, serious threat of NH3 to ecosystems. Our present funding largely comes from fundamentally oriented organizations (DFG), and we are interested to make the results suitable and useful in the interdisciplinary INMS environment, e.g. for the implementation in dynamic global models.