Rapeseed straw
Rapeseed straw is the term used to describe the plant residues that remain on the field after the rapeseed has been harvested, which arise as organic deposits in agriculture as by-products or harvest residues as stalk-like biomass . The straw consists mainly of the dried stalk and pod remains. It is usually worked into the soil after the harvest and thus serves to return nutrients and humus .
Emergence and recovery
The grain-to-straw ratio of rapeseed is around 1: 2.9, so that with an average grain yield of around 3.5 t per hectare and year, theoretically 10 t of harvest residues in the form of rapeseed straw remain in the field. As with other straw fractions, especially maize and cereal straw, a large part of the amount of straw that accumulates in rape remains chopped on the field as a humus-forming substrate. The maximum recovery rate is around 50 to 80% of the total plant remains, i.e. around 5 to 8 t / ha of rapeseed straw per year. In Germany, rapeseed is grown on around 1.4 million hectares per year, resulting in a usable volume of around 7 million t of rapeseed straw for Germany alone.
Rapeseed straw is rarely used for material or energy purposes. However, it can also be used as insulation or bedding in stables , and it can also be burned to generate bioenergy . Rapeseed straw has a calorific value of 18.1 MJ / kg and at the time of harvest it has a water content of 45–60 percent, which means that it has to be re-dried in the field.
supporting documents
- ↑ Martin Kaltschmitt, Hans Hartmann and Hermann Hofbauer (eds.), 2009: Energy from biomass. Basics, techniques and procedures. Springer Verlag, 2nd edition, p. 360, ISBN 978-3-540-85094-6 .
literature
- Stalk-like biomass: Oilseed straw In: Martin Kaltschmitt, Hans Hartmann, Hermann Hofbauer (Hrsg.): Energy from biomass. Basics, techniques and procedures. Springer Verlag, Berlin and Heidelberg 2009; P. 153. ISBN 978-3-540-85094-6 .