BSc. Project (BS303)

Duncan Hull (1996) Bachelor of Science Project (BS303). Supervisors: John H. Tallis and Jac A. Potter

The regulation of CO₂ efflux from a sub-arctic heathland

Abstract

The effects of climatic changes on CO₂ efflux from a sub-arctic heathland in Swedish Lappland (Abisko Naturvetenskapliga) were studied using Infra-Red Gas Analysis (IRGA). Climatic changes of increased precipitation and soil temperatures were simulated with open-topped polythene tents and an external water supply. Two complete diel cycles of simulated climatic change and were recorded showing increased CO₂ efflux of up to 20% over the control. The results provide evidence to support the hypothesis that increased soil temperature and precipitation could lead to increased CO₂ emissions from arctic and sub-arctic ecosystems.

The results are discussed with reference to the availability of soil nutrients as a regulatory factor of CO₂ efflux from sub-arctic heathlands.

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