Sound fields and sonic landscapes in rural environments

Abstract

The anthropocentric sonic landscape consists of the immediate soundscape extending to 20‑200 metres from the receiver; outside this is the distant soundscape, reaching out to 15‑20 kilometres. There is usually a great number of different abiotic and biotic sound sources, surrounded by their own sound fields in the anthropocentric soundscape.

Climatic and topographic elements cause considerable deformations of the theoretically calculated extension and shape of sound fields and soundscapes. Sound level measurements of wind‑generated sounds on wooded skerries in the archipelago of SW‑Finland show that there is an almost linear relation between wind velocity and the mean sound level at wind speeds between 5 and 20 m/s. Some biotic sounds from insects and birds have been measured and analyzed with respect to their sound level and octave‑band dispersion.

Besides measurements of the background sound level in rural landscapes, octave‑band analyses of some informative sounds, such as ringing church bells and fog signals from vessels, have also been made. Different kinds of disturbing noise in rural recreational environments are discussed. Attention is paid primarily to the traffic noise from small boats, ferries and snowmobiles.