Effekte der Agrarholzproduktion auf den Kohlenstoff- und Nährstoffhaushalt des Bodens im Bereich der Lausitzer Bergbaufolgelandschaft

Auf einem Rekultivierungsstandort des Lausitzer Braunkohlereviers wurde vor 4 Jahren die Baumart Robinie (Robinia pseudoacacia) angepflanzt und im Kurzumtriebverfahren bewirtschaftet. Es wurde untersucht, ob sich die Robinie positiv auf die Humusakkumulation im Boden auswirkt und welchen Einfluß die latente Nährstoffarmut (insbesondere im Hinblick auf Phosphor) des Substrates auf das Wuchspotential dieser Baumart ausübt. Die Ergebnisse zeigen, dass es unter Robinie innerhalb kurzer Zeit nach Flächenanlage zu einer Humus- bzw. Kohlenstoffakkumulation im Kippsubstrat kommt, worin ein Beitrag zur Erhöhung der Fruchtbarkeit des Standortes gesehen wird. Die durchschnittliche Zuwachsleistung der Robinie ist allerdings durch die geringe P Verfügbarkeit im Substrat deutlich eingeschränkt, wie durch eine versuchsweise P Düngung gezeigt werden konnte. Allerdings war die P-induzierte Wuchssteigerung von nur kurzer Dauer, da bereits eine Vegetationsperiode später der Düngeeffekt nicht mehr nachweisbar war

Blattstreu-Umsatz in Robinien-Kurzumtriebsplantagen auf Lausitzer Tagebau-Rekultivierungsflächen

Ein wichtiges Ziel der Flächenrekultivierung in der Lausitzer Braunkohlen-Tagebauregion ist die nachhaltige Bodenverbesserung durch Anreicherung von Humus in den sich auf den nährstoffarmen Kippsubstraten entwickelnden Böden. Mit Hilfe eines Streubeutel-Experiments wurde während der Vegetationsperiode 2010 die Abbaubarkeit von Laubstreu der Robinie (Robinia pseudoacacia L.) in vier unterschiedlich alten und verschieden bewirtschafteten Kurzumtriebsplantagen zur Biomasseproduktion auf Rekultivierungsflächen in der Region untersucht. Die Auswertung ergab, dass im Mittel nach einer Vegetationsperiode rund 40 % der Laubstreu abgebaut worden war, womit eine vergleichsweise gute Umsetzbarkeit der Robinien-Streu festgestellt werden konnte. Wird die vergleichsweise hohe Wuchsleistung auf den Rekultivierungsstandorten sowie der zusätzliche N-Eintrag durch die N2-fixierende Robinie berücksichtigt, kann demzufolge für Robinie ein nennenswertes Potential zur Bodenverbesserung auf den Rekultivierungsstandorten abgeleitet werden

Yield prediction of young black locust (Robinia pseudoacacia L.) plantations for woody biomass production using allometric relations

<span>Black locust (</span><em>Robinia pseudoacacia</em><span> L.) is an increasingly popular tree species for the production of woody biomass for bioenergy generation with short rotation coppices. Due to its potential to produce large amounts of biomass yields even under unfavourable growth conditions, this tree species is especially suitable for marginal sites, such as can be found in the post mining area of NE-Germany. Current research aims to reliably predict the yield potential of black locust short rotation coppices, but suffers from a lack of sufficient exact allometric functions until recently. This is especially true for the early growth years, which are of special importance for short rotation coppices. The objective of this study was to develop allometric equations based on tree height and shoot basal diameter (SBD) for estimating yields of young black locust plantations. Therefore, dendrometric data were collected in a two, three, four and fourteen years old black locust short rotation forest located in the reclamation area of an opencast-lignite mining area in the Lower Lusatian region (Germany) and used for equation developing. Until measurement, none of the plantations had been harvested. Closed correlations between SBD and tree height were observed, as well as between these parameters and single tree mass. The scattering of single tree masses could be explained slightly better by the SBD than by the tree height. In the year before a harvest an even better prediction probability of woody biomass was obtainable when both parameters were simultaneously interrelated with the single tree mass. The results illustrate that the woody above ground biomass of young black locust plantations can be estimated sufficiently precisely based on the easy determinable parameters tree height and particularly SBD.</span

Yield prediction of young black locust (Robinia pseudoacacia L.) plantations for woody biomass production using allometric relations

Black locust (Robinia pseudoacacia L.) is an increasingly popular tree species for the production of woody biomass for bioenergy generation with short rotation coppices. Due to its potential to produce large amounts of biomass yields even under unfavourable growth conditions, this tree species is especially suitable for marginal sites, such as can be found in the post mining area of NE-Germany. Current research aims to reliably predict the yield potential of black locust short rotation coppices, but suffers from a lack of sufficient exact allometric functions until recently. This is especially true for the early growth years, which are of special importance for short rotation coppices. The objective of this study was to develop allometric equations based on tree height and shoot basal diameter (SBD) for estimating yields of young black locust plantations. Therefore, dendrometric data were collected in a two, three, four and fourteen years old black locust short rotation forest located in the reclamation area of an opencast-lignite mining area in the Lower Lusatian region (Germany) and used for equation developing. Until measurement, none of the plantations had been harvested. Closed correlations between SBD and tree height were observed, as well as between these parameters and single tree mass. The scattering of single tree masses could be explained slightly better by the SBD than by the tree height. In the year before a harvest an even better prediction probability of woody biomass was obtainable when both parameters were simultaneously interrelated with the single tree mass. The results illustrate that the woody above ground biomass of young black locust plantations can be estimated sufficiently precisely based on the easy determinable parameters tree height and particularly SBD

Biomass, Carbon and Nitrogen Distribution in Living Woody Plant Parts of Robinia pseudoacacia

In the lignite mining region of Lower Lusatia (NE-Germany), Robinia pseudoacacia L. is an increasingly popular tree for the biomass production with short rotation coppices (SRCs) on reclamation sites. In order to evaluate biomass production, C and N allocation patterns in R. pseudoacacia stands between shoot, stump, coarse, and fine roots samples were collected from seedlings and three adjacent plantations and plants that were one, two and twelve years old. Results indicated that the summarized average dry matter production (DM) of the woody plant parts increased with plant age up to 7.45 t DM ha−1 yr−1 with a corresponding shoot increment of up to 4.77 t DM ha−1 yr−1 in the twelve-year-old stands. The shoot to root ratio changed from 0.2 for the one-year-old trees to 2.0 in the twelve-year-old plantation, whereby an average amount of 3.4 t C ha−1 yr−1 and 0.1 t N ha−1 yr−1 was annually bound in the living woody plant parts over the period of twelve years. Summing up, the results suggest a high potential for C and N storage of R. pseudoacacia what is also beneficial for land reclamation due to positive implications on soil humus and general site fertility