Ecophysiology of pioneer trees

photosynthesis measurment with Li-Cor 6400 Porometer systemRobinia stands on reclaimed post-mining sitesInvestigation of light environment in Robinia standsImpact of soil water content on grwoth of hybrid-poplars

  • Modelling photosynthesis and biomass allocation of hybrid-poplar and black locust

For a better understanding of biomass production of fast-growing trees in agroforestry systems more detailed ecophysiological informations and their annual carbon balances are required. Carbon gain by photosynthesis is a predominant factor for plant growth and to estimate biomass allocation at the tree, stand and landscape level. Hence, biochemical photosynthesis models are widely used to estimate diurnal and annual carbon uptake on the leaf level and scaling up to predict carbon fluxes on the canopy level. However, biochemical parameters are often difficult to determine under field conditions, and therefore we develop an empirical photosynthesis model based on gas exchange parameters and their dependence from microclimatic parameters, which can be easily obtained in the field. For up-scaling from leaf photosynthesis to annual tree carbon balance the structure of hedgerow, which is influencing the physiological functions and interactions must be taken into account. Our specific objectives are, therefore, to developed a leaf carbon model driven by light and modulated by temperature and air humidity. The seasonal variation of CO2 uptake and release can be then modeled and up-scaled to estimate the annual carbon fluxes of sun and shade leaves.

  • Water use and growth of black locust in post-mining areas in Lower Lusatia

The high ecological plasticity makes Robinia an alternative tree species for reclamation of post-mining sites in the Lusatia region (Brandenburg, Germany), especially in areas, where agricultural crop production comes to its limits. Aftermaths in those areas include nutrients scarcity and water limitation due to relatively low soil water holding capacity and deep groundwater table, which magnified the drought effect on the primary production and plant survival during drought periods in late-spring and summer. Therefore, the establishment of forests, short-rotation copices and agroforestry systems instead of conventional agricultural production with annual crops is an alternative land-use form for this area. Hereby, black locust becomes a key species on such recultivated areas, for enanching the soil fertility due its capability of symbiotic biological nitrogen fixation. Further the importance of Rhizobia association on the resilience of the species to overcome unfavorable edaphic condition is an additional advantage in such degraded ecosystems. Read more..

Further cooperations

Simulating of the growth performance of poplar and black locust trees in an alley-cropping system in southern Brandenburg and Lower Saxony (Germany)

In cooperation with Diana Seserman (PhD project), Dirk Freese (BTU Cottbus-Senftenberg), Ina Pohle (The James Hutton Institute, Environmental and Biochemical Sciences, Aberdeen, UK).

Growth and intra-specific competition of Robinia pseudoacacia in southern Brandenburg (Lower Lusatia, NE Germany)

In cooperation with Christin Carl (PhD project), Peter Biber, Hans Pretsch (TU München, Insititute of Forestry and Resoource Management), Dirk Landgraf (FH Erfurt)

 © Maik Veste 2018 - Update 18JUNE2018                                          Impressum