TY  - THES
AU  - Busch, Franziska
TI  - Dynamics of greenhouse gas emissions and nitrogen availability asinfluenced by biochar particles during composting
PB  - University of Bonn
VL  - Masterarbeit
M1  - FZJ-2026-01594
SP  - 60
PY  - 2023
N1  - Masterarbeit, University of Bonn, 2023
AB  - In this study, a 148-day composting of vegetable waste, horse manure and wheat straw wasconducted to investigate the greenhouse gas (GHG) emissions and nitrogen (N) dynamics asinfluenced by the addition of biochar (bc). A special research focus has been placed on theretention of the N-forms by the bc. GHG (CO2, CH4, N2O) were measured with gas chromatographyand mineral N of the compost substrate was analyzed with standard methods (0.01 molL−1 CaCl2). In addition, N retained by bc particles was analyzed by a three-stage extraction procedureand bc particles were also analyzed by 13C NMR spectroscopy. These methods provideda comprehensive insight into the temporal dynamics of GHG emissions, the amount and availabilityof N retained by bc particles, and the change in chemical groups of bc during compostingwith bc amendment. The addition of bc (15%) did not significantly reduce or increase GHGemissions compared to the control (ctrl) compost. Cumulative emissions averaged at 4016(ctrl) and 3706 (bc) g CO2-C m−2, 2171 (ctrl) and 3332 (bc) mg CH4-C m−2 and 715 (ctrl) and562.8 (bc) mg N2O-N m−2. The concentrations of NH4+–N, NO3––N, NO2––N did not differ significantlybetween the treatments, but significantly higher (54%) total amounts of NO3––N (gpile−1) were measured for the whole compost pile in the bc treatment, indicating lower NO3–1losses throughout the composting. The retention of N forms by bc particles was not reflectedin significantly lower N2O emissions. However, N forms were effectively retained in varyingdegrees of strength by the bc particles. The NH4+–N concentrations that could be extractedfrom the bc particles decreased during the composting process. The percentage distributionshows a clear transition from predominantly plant-available (55%) at the beginning of compostingto predominantly tightly bound (75%) NH4+–N in the final compost. At the end of thecomposting process, the extractable NO3––N concentration from bc particles was 164 mg kg−1(easily extractable), 80 mg kg−1 (not available) and 194 mg kg−1 (strongly retained). Until thelast day of composting, these concentrations increased continuously with a distribution towardsrather strongly bound NO3––N. It can be concluded that the addition of bc tended toprotect against N losses.
LB  - PUB:(DE-HGF)19
DO  - DOI:10.34734/FZJ-2026-01594
UR  - https://juser.fz-juelich.de/record/1053896
ER  -