Continuous monitoring of gas exchange in open‐top chambers in pollution experiments: methodological aspects

Abstract

As part of an experiment on effects of atmospheric pollution on the physiology of spruce trees (Picea abies (L.) Karsten), a method for continuous monitoring of gas exchange of young trees grown in Open Top Chambers (OTC) was developed. The basic principles and feasibility of this method are first presented in detail. The installation of a fine perforated polyethylene net over the top of the OTC, in order to reduce ingress of outer air, made it possible satisfactorily to monitor the gas exchange of the trees over long periods. Examples are given of typical measurements of net assimilation and transpiration fluxes for an experimental canopy of 15 young spruce trees to show diurnal and seasonal variation. Copyright © 1995, Wiley Blackwell. All rights reserved