University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Simon Reiter
(2016):
KOMPOSTIERUNG VON FUTTERLEGUMINOSEN-STROH-GEMENGEN
Nährstoffbilanzierung und Wirkung von Zusätzen.
Master / Diploma Thesis - Institut für Ökologischer Landbau (IFÖL),
BOKU-Universität für Bodenkultur,
pp 131.
UB BOKU
obvsg
- Abstract:
- As stockless farming becomes more important in organic agriculture composting of fodder legumes instead of mulching is discussed to avoid negative effects regarding N-supply to crop rotations. There’s little knowledge about losses of nutrients during composting. Losses of organic carbon (C), nitrogen (N), phosphorus (P) and potassium (K) were investigated when composting grass-clover (GC) and straw (S) with some mature compost (MC) for 10 weeks at an organic farm in Austria. Rock powder and biochar were tested as amendments. Four windrows were formed (% by mass): I: GC+S+MC, C/N=34; II: GC+ S+MC, C/N=48; III: GC+S+MC+rock powder (5 %), C/N=30; IV: GC+S+MC+biochar (13 %), C/N=43. I/III/IV contained similar amounts of GC and S; II contained more S. Leachates were collected via plastic film pools filled with wood chips. To calculate losses of nutrients calculations based on the relative changes of nutrient contents and two types of mass balances were applied. Various analyses were used to characterize the composting process: Temperature (T), moisture, pH, organic matter and nutrient contents etc. By the most reliable method (mass balance): I (standard) lost 56 % C, 26 % N (ca. one third got lost gaseous), 20 % K, 42 % P. Losses of K and P might be overestimated. High variations of the data must be taken into account, especially for K and P. II showed lower losses of N, which probably took place only via leachates. Rock powder didn’t change losses of C or N and the proportion of gaseous N-losses. Biochar (IV) didn’t reduce N-losses, but reduced C-losses and might have increased gaseous losses of N. If C-losses were referred to windrow-C without biochar-C, IV would show higher C-losses than I. The effect of rock powder and biochar on losses of K and P is unclear. Rock powder just slightly increased T; biochar increased T, CO₂-formation and resulted in higher pH-values during first weeks of composting. Further investigations are needed for statistical verification.
- Beurteilende(r): Friedel Jürgen Kurt
- 1.Mitwirkender: Binner Erwin