Das Projekt "Fine Structure of the Stably Stratified Atmospheric Boundary Layer in Antarctica" wird vom Umweltbundesamt gefördert und von Technische Universität Braunschweig, Institut für Luft- und Raumfahrtsysteme durchgeführt. As element of the cooperation between the Inst. f. Luft- und Raumfahrtsysteme, Techn. Univ. Braunschweig (ILR), and the British Antarctic Survey (HAS) in total three small meteorological flight robots (M2AV) are sent to Halley station. There the fully autonomously operating aircraft (developed at the ILR) are going to measure the turbulent characteristics of the stable atmospheric boundary layer (SBL) above the ice shelf. These in situ measurements are then used to verify, support and complete the already installed BAS sodar systems and the meteorological tower. Main research goal is the fine structure of the SBL especially regarding thin layers, intermittent and fossil turbulence, and (solitary) waves. The use of structure functions, multi-resolution co-spectra and wavelet analysis give information on the spectral characteristics of turbulent structure and transport within the layered SBL. Applying inverse models to the observed data, gradients, divergence and energy fluxes are calculated in order to quantify the turbulent energy transfer between SBL and surface, and between individual layers. Furthermore the horizontal representativeness of the installed remote sensing systems is validated. In the preceding project PSBL a large quality-controlled database from Helipod flights over Arctic sea ice (Polarstern campaigns ARK-XI, ARK-XII and ARK-XIX) was already created. This data base is now used to analyse the resemblance and difference between the SBL over shelf ice (Antarctic) and sea ice (Arctic). The project will contribute to the understanding of specific elements and processes of the SBL particularly under polar conditions. At the beginning of the project all experiments and journals will be already completed. Thus we apply only for man power to analyse the unique data sets from Halley station and M2AVs.
Das Projekt "Entwicklung von low input Systemen wie z.B. Ökologischer Landbau über einen optimierten Einsatz von Leguminosen in einer Trockenregion in Nicaragua mit dem Ziel der Verbesserung der Bodenfruchtbarkeit, des Ertrages, der Ernährung sowie dem Einkommen" wird vom Umweltbundesamt gefördert und von Universität für Bodenkultur Wien, Institut für Ökologischen Landbau durchgeführt. The overall purpose of the research is to investigate low input legume - maize cropping systems under dry climate conditions. Research area is San Dionisio, which is located in the central hillsides region of Nicaragua in the Departamento of Matagalpa. The research targets are:(a) On station trials: 1. To find out the impact of different legume species / varieties, planted in the dry season, on soil organic matter after a four year crop rotation. 2. To study the performance of different legume species / varieties about root biomass, above ground biomass, nitrogen fixation and the effects on subsequent maize performance. (b) On Farm trials: 3. To investigate the impact of cover crops/green manure (CCGM) improved residue grazing in the dry season on subsequent maize performance in comparison with non-grazed cover crops/green manure (CCGM) rotations, as well as their labour and economic impacts. 4. To analyse the impact of cover crops/green manure (CCGM) species / varieties on soil fertility and subsequent maize performance, as well as their labour and economic impacts. 5. To implement support strategies for farmer/researcher to farmer training / knowledge transfer, experience exchance - combining on station trial knowlegde with farmer specific knowledge (site specific techniques) accompanied by BSC / MSC students and local farmer organizations (Campos verdes / Suenos realizados)All trials are managed without any fertilizer nor herbicides nor pesticides following the guidelines of IFOAM. The research is carried out by Universidad National Agraria, Managua, University of BOKU, Vienna and CIAT.