System for Measuring Fluxes of Trace Gases to and from Soil and Vegetation with a Chamber Technique

摘要

A mobile system for measuring gaseous fluxes of SO2 NOx, O3 and water vapor between the atmosphere and the vegetation/soil system using a chamber technique is described. Equipment, instruments and instrumental sensitivities are listed. A gas handling system, including calibration procedures and information on the chamber construction, is also presented. With this system it is possible to make measurements using a wide range of concentrations including subambient levels. The environment in the chamber can be kept very close to ambient conditions. The mechanisms regulating the flux can be studied. A limitation of this system is the problem of extrapolating the fluxes obtained to larger areas.