treelab

Excerpt from the installation video (1 screen)

treelab
Spatial audio/stereo sound installations
2014 - 2018
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The link between trees and various climatic processes is usually not immediately apparent. Trees and plants do not live merely on moisture from rain, sunlight (which drives gas exchange) and nutrients from the soil: they absorb carbon dioxide from the air and produce the oxygen that we breathe, maintaining our climate and biosphere. Gathering ecophysiological data by measuring the local climatic and environmental variables and the physiological processes within a plant in response to changes in these variables has become an important method of researching climate change and vegetation dynamics. It helps to determine physiological thresholds of plants in terms of increasing temperature and consequently drought stress.

Plant physiologists have known that plants emit sounds for several decades now. Many of these sounds are of transpiratory/hydraulic origin and are therefore related to the circulation of water and air within the plant as part of the transpiration process. Each plant species – in fact each plant individual – has its own acoustic signature, related to its anatomical structure and to the local climatic conditions. Investigating the acoustic emissions of a tree in response to dynamically changing climatic conditions might reveal biological or physical properties that place these emissions in a broader ecophysiological context and enable us to explain processes that are not yet fully understood.

In our observation system «treelab» we combine recordings of acoustic emissions of a tree with sonic representations (sonifications) of ecophysiological data in one single auditory expe-rience, enabling the visitor to experience and comprehend cause and effect of the plant-atmosphere relationship. The installation replays measurement data from early summer 2015, the peak of the growth period of a Scots pine (Pinus sylvestris) located in the central Swiss Alps in Salgesch in the canton of Valais.

Scots pines in Valais have experienced high mortality rates for some decades now: this phenomenon is believed to be caused by the effects of climate change, e.g. longer drought periods. A downy oak (Quercus pubescens), for example, is able to better withstand the current climatic conditions whereas a Scots pine is pushed beyond its physiological limits despite the fact that both tree species have coexisted there for thousands of years. Consequently, shifts in the abundance of tree species are observed. The ecophysiological knowledge acquired is used to explain the underlying processes: Hence the cooperation between a biologist and an artist opens up new ways to study the complex relationship between tree physiology and climatic conditions on the one hand and to explore the possibilities of acoustic and artistic representations of ecophysiological processes in trees on the other.