|Präsentation: Tagung Agrarholz: C. Baum, P. Kahle, J. Köhn and P. Leinweber, Berlin 2013|
|Soil- and socio-ecological impacts of short rotation coppices |
– An evaluation report and a proposal for an integrated management scheme -
The use of biomass to produce energy (power, heat and fuel) is seen a carbon neu-tral and therefore climate impact neutral business. Cradle-to-grave life cycle analyses show that this not due for any kind of biomass. Hence, the analyses of agricultural soils cultivated with poplar or willow in short rotation coppices (SRC) have shown that SRC may increase the natural carbon sink in the soils. These might increase the soil fertility in the long term. Thus, the ecological and basic economic results have been evaluated by the use of integrated ecological and socio-ecological tools. Soil ecological results and the socio-economic frameworks in Sweden in Germany were compared and evaluated. Selected results from the former ERA Net project RATING-SRC and subsequent investigations on SRC sites in Germany and Sweden will be presented. Chemical, physical and biological soil properties were measured under SRC and adjacent arable sites with annual crops. The changed quality and quantity of leave and root litter and the lack of tillage under SRC can lead to an increased carbon accumulation and a changed soil organic matter quality, a decreased bulk density and a changed microbial activity and diversity. The soil ecological significance of SRC differs widely between different tree taxa and even on the clone-level. Therefore, bioindicators, like e.g. clone-specific concentrations of foliar waxes, were proposed for the selection of the most promising clones to improve the soil fertility of arable soils in the long term. These results may also explain why farmers observed a substantial increase of yields after the SRC has been turned again in arable land used for annual crops such as grain or rape seed.