<div class="htmlview paragraph">For botanical experiments with durations of several months (EURECA BOTANY FACILITY and COLUMBUS GRAVITATIONAL BIOLOGY FACILITY) consumables like water, carbondioxide, oxygen and phytotoxin removal gas may contribute significantly to the weight of a Life Support Subsystem (LSS).</div> <div class="htmlview paragraph">Since the amount of such consumables has a significant influence on the optimum choice of the LSS, a literature survey has been performed to obtain realistic values which may be used for preliminary design purposes.</div> <div class="htmlview paragraph">Based on a comparison of the likely performance requirements the LSS of Orbital Botanical Facilities (OBF) and the Environmental Control and Life Support Subsystem (ECLSS) of the carrier, various LSS concepts are discussed which interact to a varying degree with the ECLSS. Interaction means in this case that the ECLSS is used as a resource for the consumables needed by the LSS.</div> <div class="htmlview paragraph">Advantages and disadvantages of such interaction, in particular weight savings and technical complexity are addressed.</div>