University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Alya Allegra Kingsland-Mengi
(2022):
Carbon accumulation and fractionation in soils beneath hedge rows at early stages after conversion.
Master / Diploma Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 49.
UB BOKU
obvsg
- Abstract:
- Soil organic carbon (SOC) consists of different C fractions with differing stabilities, and plays an important role in terrestrial ecosystems. With the attention the SOC pool has attracted as a feasible strategy for climate change mitigation, it is important to understand the amount and composition of SOC in differing land use systems, and the underlying mechanisms that stabilize SOC. Re-establishment of native vegetation can facilitate SOC recovery, offering sinks for rising atmospheric CO2. Arable fields and adjacent recently converted hedgerow soils in Lower Austria were selected to explore the influence of management. With the 3 sites chosen, the objective was to investigate the changes in SOC fractions in arable soils and post hedgerow converted soils with particle size fractionation via ultrasonic aggregate dispersion and wet sieving. As SOC varies in persistence, relationships between SOC in the fine fraction (f<20 μm) and soil physico-chemical properties that are expected to influence C accumulation in soil were analyzed, such characteristics included oxalate-extractable aluminum (Alo) and iron (Feo), specific surface area (SSA), and cation exchange capacity (CEC). SOC enrichment under hedgerows was present in the coarse fractions f>20 μm, however such relationship was not significant in the fine fraction f<20 μm. Stepwise linear regression analysis was conducted to identify potentially important variables for predicting variations in SOC. While a positive relationship was evident between soil characteristics and SOC, Al/Fe oxides and exchangeable bivalent cations are determining to large extent the amount of C in the <20 μm fraction, highlighting their role in carbon stabilization. Saturation potential for mineral protected C was estimated utilizing boundary line (BL) regression, and revealed an unused storage potential of soils in terrestrial ecosystems, however, more sites and data are required to validate the detected trends.
- Beurteilende*r: Wenzel Walter