Title:
Degradation of Soil Amendments Produced from Municipal Organic Waste Digestate During a Two-Year Field Study
Author(s):
Knoop, C., Dietrich, N., Heinrich, M., Dornack, C., Raab, T.
Document(s):
Paper
Poster
Abstract:
The structural degradation of agricultural soils is an increasing problem of our times caused by intense land use. The treatment of soils with organic amendments shall maintain and improve long-term soil fertility. Solid residues from anaerobic digestion of municipal organic waste (MOW) are rich in nutrients and organic matter and have a promising potential to be used as soil amendment. Our research investigates the characteristics of differently treated amendments produced from MOW digestate. We want to know how long these amendments are present in the soil and which amendment type contributes most to nutrient provision after application. Results were obtained using four different MOW digestate amendments of one origin (loose, pelletized and agglomerated) during a 24-hours shaker-experiment and a bag-experiment on grassland, which was subsequently sampled over 21 months. Results show that short-term element leaching is higher from loose amendment and small agglomerates, probably caused by higher surface area und lower stability of these amendments. Biggest degradation effects can be seen 7 months after application to soil. However, all four amendments are still present after 21 months. Pelletized amendments are more degradation resistant than loose amendment, which may be advantageous regarding long-term effects e.g. on water holding capacity. In turn, loose material delivers a higher share of small organic particles to soil and may therefore have a higher contribution to humus development
Keywords:
anaerobic digestion, organic waste, soil fertility, pelletization, digestate recycling
Topic:
Biomass Policies, Markets and Sustainability
Subtopic:
Environmental impacts of bioenergy
Event:
25th European Biomass Conference and Exhibition
Session:
4AV.2.14
Pages:
1720 - 1723
ISBN:
978-88-89407-17-2
Paper DOI:
10.5071/25thEUBCE2017-4AV.2.14
Price:
FREE
