Sound Absorption Properties of Tropical Plants

The paper presents the experimental results of sound absorption coefficient measurements of several tropical plants, including fern, baby tears, begonia, maidenhair fern and ivy. All these plants live in tropical underbrush in conditions of low lighting, warm temperature and high relative humidity, conditions that can be often found inside common buildings. A vertically mounted impedance tube with a diameter of 100 mm is used in accordance with ISO 10534-2 method to determine the absorption coefficient spectra. A substrate made of coconut and per- lite soil for hydroponics is used with all the samples. It is chosen because of its high porosity and, as a result, good sound absorption properties. The paper also presents the random inci- dence absorption coefficient spectra which were measured in a reverberating room in accord- ance with ISO 354. The aim of this research is to investigate the feasibility of introducing ab- sorptive panels made of living plants as a replacement for conventional man-made acoustic treatment of surface used to improve the acoustic quality of indoor spaces.