TY - GEN A1 - Mantovani, Dario A1 - Veste, Maik A1 - Boldt-Burisch, Katja A1 - Fritsch, Simone A1 - Koning, Laurie Anne A1 - Freese, Dirk T1 - Carbon allocation, nodulation, and biological nitrogen fixation of black locust (Robinia pseudoacacia L.) under soil water limitation T2 - Annals of Forest Research N2 - The pioneer tree black locust (Robinia pseudoacacia L.) is a drought-resistant tree and, in symbiosis with Rhizobium, able to fix dinitrogen from the atmosphere. It is, therefore, an interesting species for marginal lands where soil amelioration is sought in addition to economic gain. However, the interaction between soil water availability, carbon allocation and nitrogen fixation is important for a successful establishment of trees on marginal lands and has not yet been investigated for black locust. Twoyear-old trees were grown under various soil water conditions and drought cycles. The stable isotopic composition of C (δ 13C) and N (δ 15N) of the leaves was used to identify i) the effective drought condition of the treatments and ii) the portion N accrued from the atmosphere by the biological nitrogen fixation. Drought-stressed plants significantly reduced their total aboveground biomass production, which was linearly linked to tree transpiration. The shoot:root ratio values changed from 2.2 for the drought-stressed to 4.3 for the well-watered plants. Our investigation shows that drought stress increases the nodule biomass of black locust in order to maintain biological nitrogen fixation and to counteract the lower soil nitrogen availability. The biological nitrogen fixation of drought-stressed trees could be maintained at relatively higher values compared to the well-watered trees. The average leaf nitrogen content varied between 2.8% and 3.0% and was not influenced by the drought stress. Carbon fixation, carbon allocation, and biological nitrogen fixation are to some extent balanced at low irrigation and allow Robinia to cope with long-term water constraints. The combination of black locust’s ecophysiological and morphological plasticity make it interesting as a biomass source for bioenergy and timber production, even in nutrient-limited and drought-affected areas of Europe. Y1 - 2015 U6 - https://doi.org/10.15287/afr.2015.420 SN - 2065-2445 VL - 58 IS - 2 SP - 259 EP - 274 ER - TY - CHAP A1 - Mantovani, Dario A1 - Veste, Maik A1 - Boldt-Burisch, Katja A1 - Fritsch, Simone ED - Jeltsch, Florian ED - Joshi, Jasmin T1 - Black locust (Robinia pseudoacacia L.) root growth response to different irrigation regimes T2 - GfÖ 43rd Annual Meeting, Building bridges in ecology, linking systems, scales and disciplines, September 9 to 13, 2013, Potsdam, Germany N2 - Robinia pseudoacacia L. is a pioneer tree species native from North America. Its original range is a climatic region classified as humid to sub-humid, with a mean annual precipitation of 1020 to 1830 mm. However, it grows under a wide range of edaphic and climatic conditions and the species has proven to be relatively drought tolerant. In central Europe, with a continental climate, the species has been successfully cropped for biomass production also on marginal land, even in post-­‐mining areas characterized by water limitation and harsh edaphic conditions. Due its drought tolerance, fast resprouting rate and its ability to live in symbiosis with Rhizobia and thus fix atmospheric nitrogen, black locust could become a key species for short-­‐rotation plantation on marginal land. Several studies have been already carried out to quantify the black locust above ground production and its water use efficiency. However, the relation between the black locust biomass allocation, root system development and plant water use has still to be examined. In our study we evaluated the drought stress effect on black locust below ground biomass production, root distribution, and the root and rhizobial association. Different irrigation regimes were chosen to test the plant’s performance in a lysimeter experiment, under semi-­‐controlled environmental conditions, for the duration of two vegetation periods. From the results obtained we determined the root biomass allocation under different irrigation regimes and identified the close relation between the soil water condition and the rhizobial association. Y1 - 2013 UR - http://www.gfoe-2013.de/download/130905_GFOe_2013_Abstracts.small.pdf SP - 33 EP - 34 ER -