University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
André Wittmann
(2020):
„Biological drivers of soil aggregate stability under different tillage intensities”.
Master / Diploma Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 63.
UB BOKU
obvsg
FullText
- Abstract:
- Soil tillage systems are in the focus of sustainable agricultural practices. Two different systems are often compared, conventional and conservation tillage. The mechanical disturbance during tillage has detrimental effects on soil organisms, like earthworms and fungal hyphae and hence reduces soil aggregate stability (SAS). Conservation tillage practices can reduce soil erosion and, hence, mitigate soil organic carbon (SOC) losses. This study aims to determine the effects of long-term soil management on SOC concentration, SAS as well as fungal biomarkers and microbial necromass and potential relationships therein in bulk and rhizosphere soil and earthworm casts. To elucidate tillage effects an experimental field that was subject to four different tillage intensities, (i) conventional tillage (CT), (ii) reduced tillage (RT), (iii) minimum tillage (MT) and (iv) no-tillage (NT) since 2006, was sampled summer 2019. On each of the three replicate plots per treatment earthworm enriched sub-plots were set up by installing fences and 15 Lumbricus terrestris were added. Soil samples were taken from bulk and rhizosphere soil of each plot and from earthworm sub-plots. SAS analysis was negatively related with tillage intensity. Further, conservation tillage plots (NT and MT) showed highest amounts of SOC and DOC as well as ergosterol, glomalin and amino sugars. The highest values of the biological parameters were observed in MT, while SAS was highest in NT. This indicates stimulation of microbial growth by minor soil disturbance. Short term application of earthworms did not affect SOC but showed higher DOC concentrations than bulk and rhizosphere soils. We conclude that conservation tillage practices such as MT are beneficial for SOC likely via soil biological parameters compared to CT.
- Beurteilende(r): Keiblinger Katharina
- 1.Mitwirkender: Bodner Gernot
- 2.Mitwirkender: Euteneuer Pia