The response of dissolved carbon dynamics to environmental change in upland shallow organic soils: a study of organic horizon responsiveness and soil horizon interactions

The response of dissolved carbon dynamics to environmental change in upland shallow organic soils: a study of organic horizon responsiveness. and soil horizon interactions Katherine L. Chadwick This thesis examined the relatively uncharted realm of dissolved C dynamics in upland shallow organic soils. Extensive preliminary investigations and preparatory experimental evaluations led - ~ to the successful deployment of sampling --strategies at a range of spatial scales in a climosequence of matched field sites in Wales, Scotland and Iceland. These sites provided the basis for investigation of climatic and mineralogical effects upon dissolved C transformation~ in upland shallow organic soils. Biological assessments including novel application of modified techniques identified the responsiveness of these soils to environmental perturbations at a range of experimental scales, and over varied temporal periods. As C loss from upland organic soils requires both degradation of SOM and export of degraded C via soluJion percolation and flushing or gaseous exchange, the capacity of the different mineral horizons to retain degraded C, and indeed the quality of the bound C, is of consequence to soil C source-sink understanding. The combined roles of organic and mineral horizons in C turnover potential and retention capability, indicate the in;tportance ofupland shallow organic soils in modelling soil C dynamics in response to climate change. This highlights the necessity of sustainable management of these upland areas within the northern hemisphere. KEYWORDS: Carbon; Upland; Organic soil; Climate; Latitude; Horizons; Phenol oxidase; Hydrolases, Turnover, Biodegradation.EThOS - Electronic Theses Online ServiceGBUnited Kingdo