Craigiebuckler, Aberdeen, AB15 8QH, UK RECIPE Final Aberdeen Progress meeting 29-31/05/2006 WP02 – Carbon sequestration by peatland vegetation UK progress Rebekka Artz Stephen Chapman

I. WP1 UK Field site data D5 Identification of key species successfully occupying abandoned sites and their potential for restoring peat accumulation 1) vegetation surveys – completed. Stats completed. All four sites have significantly different vegetation structure (by PCACVA). 2) net biomass data at end of growth period, but no LAI data 3) gaseous flux datasets from 13/11/03-14/10/04 (14 points)

Dark CO 2 production -modelling Bare peat, total respiration models (r2 = 0.6 (WT), cm). D6 Rates of carbon return from key species used in the restoration of sites

CO 2 fluxes 2 – PGCO 2 E. angustifolium + S. auric. Collars (site B), r2 = 0.72

D7 Rates of C fixation on an area basis etc……major modelling problems Not enough data to model per collar, trying to overcome this by pooling data from replicate collars (Mika found that this doesn’t always work well…) Rtot modelling produces very low r2 values – a lot of data had to be excluded as either missed dark measurements or negative dark fluxes PGCO2 modelling ok, but lack of LAI data forces use of other seasonality index, both air and -5 cm temps seem to work ok Will try using the Finnish model to see if this simulates our data reasonably well after this meeting…..

II. WP2 …. Problems with negative dark fluxes (i.e. CO2 uptake) probably caused by our large chambers and an overly sensitive IRGA system (when checking data all these fluxes had low r2 values, i.e <0.8), later data (post 02/05) much better but not enough data (only 3 time points) for modelling! CO 2 flux (mg CO 2 m-2 d-1)

CH 4 flux (mg CH 4 m-2 d-1)