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Sonderforschungsbereich (SFB) 607: Wachstum oder Parasitenabwehr? Wettbewerb um Ressourcen in Nutzpflanzen aus Land- und Forstwirtschaft, Teilprojekt B1: Allometrie und Raumbesetzung von krautigen und holzigen Pflanzen. Integration von Pflanzen- und Bestandesebene

Das Projekt B1 'Allometrie und Raumbesetzung von krautigen und holzigen Pflanzen' ist Teil des Sonderforschungsbereiches 607 Wachstum und Parasitenabwehr und befindet sich bereits in der vierten Phase des seit 1998 laufenden Forschungsprojektes. Bisher wurde im Projekt B1 die Allometrie als Resultat der pflanzeninternen Steuerung der Allokation untersucht. Auf Individuenebene wurden Allometrie und ihre Veränderung für verschiedene Baumarten in verschiedenen ontogenetischen Stadien untersucht. Auf Bestandesebene wurden die self-thinning-Linien von Yoda und Reineke für krautige bzw. holzige Pflanzenbestände analysiert. Bisherige Allometriebestimmungen erbrachten für diese Arten zwar ähnliche Größenordnung aber auch charakteristische Unterschiede, die Ausdruck spezifischer Strategien der Raumbesetzung und -ausbeutung widerspiegeln. Die bisher vereinzelten Auswertungen sollen in Phase IV in eine übergreifende Analyse (versch. Arten, ontogenetische Stadien, Konkurrenzsituationen, Störfaktoren) der Allometrie auf Pflanzen- und Bestandesebene münden.

Hydrogeological and hydrochemical modelling of density-driven flow in the Tiberias Basin, in particular between Ha'on and Tiberias Regions, Jordan Valley

The aim of the current research is to identify regional sources and trans-boundary flow leading to the observed salinity of Lake Tiberias (LT) -also known as the Sea of Galilee or Lake Kinneret-, and its surroundings, which is considered the only natural surface fresh water reservoir of the area. The current study will include all sources of brines in the Tiberias Basin (TB) with specific emphasis of the relationship between the brines from the Ha'on and Tiberias Regions (HTR).The tasks will be achieved by a multidisciplinary approach involving: (i) numerical modelling of density-driven flow processes (i.e., coupled heat and dissolution of evaporites), (ii) hydrochemical studies, supplemented by investigations of subsurface structures.(i) Numerical modelling will be carried out by applying the commercial software FEFLOW® (WASY, GmbH) complemented with the open source code OpenGeoSys developed at the UFZ of Leipzig (Wang et al., 2009). The final goal is to build a 3D regional-scale model of density-driven flow that will result in: (1) revealing the different interactions between fresh groundwater and natural salinity sources (2) elucidate the driving mechanisms of natural brines and brackish water body's movements.(ii) Hydrochemical study will include major, minor and, if possible, rare earth elements (REE) as well as isotope studies. The samples will be analysed at the FU Berlin and UFZ Halle laboratories. Geochemical data interpretation and inverse modelling will be supported by PHREEQC. Hydrochemical field investigations will be carried out in Tiberias basin and its enclosing heights, i.e. the Golan, Eastern Galilee and northern Ajloun in order to search for indications of the presence of deep, relic saline groundwater infested by the inferred Ha'on mother-brine. The current approaches will be supplemented by seismic and statistical data analysis as well as GIS software applications for the definition of the subsurface structures. The key research challenges are: building a 3D structural model of selected regions of TB, adapting both structural and hydrochemical data to the numerical requirements of the model; calibrating the 3D regional-scale model with observational data. The results of this work are expected to establish suitable water-management strategies for the exploitation of freshwater from the lake and from the adjacent aquifers while reducing salinization processes induced by both local and regional brines.

Landschaftsveränderungsdienst - Laverdi

Die Erkennung von Veränderungen der Landbedeckung der Erdoberfläche auf der Basis von satellitengestützten Fernerkundungsdaten ist seit Jahrzehnten ein sehr aktives Forschungsfeld. Das Ziel des Landschaftsveränderungsdiensts ist es, freie Copernicus-Satellitendaten für eine automatische Ableitung von Landbedeckungsänderungen zu nutzen und diese Informationen regelmäßig für einzelne Landschaftselemente (z.B. für Waldgebiete, Wasserflächen, Landwirtschaftsflächen usw.) über einen Web Service bereitzustellen. Copernicus Daten eignen sich aufgrund der hohen zeitlichen (ca. 3-5 Tage, je nach Sensor) und mittleren räumlichen Auflösung (ab 10m) ideal für eine regelmäßige bundesweite flächendeckende Analyse der Landbedeckung. Um eine hohe Bearbeitungsleistung zu erreichen wird die 'Copernicus Data and Exploitation Platform - Deutschland' (CODE-DE) für die Datenverarbeitung und -analyse genutzt. Es können aktuelle und konsistenteste Informationen über Landdeckungsänderungen abgeleitet werden, um kontinuierlich Geodaten in einer einheitlichen Qualität zu pflegen (siehe Abbildung 1). Andererseits können die gewonnenen Informationen genutzt werden, um statistisch relevante Geoinformationen zur quantitativen Beschreibung der UN-SDG-Indikatoren zu extrahieren. Die 2015 verabschiedete Agenda 2030 mit 17 Entwicklungszielen (SDG) und 169 Unterzielen verknüpft das Prinzip der Nachhaltigkeit mit der ökonomischen, ökologischen und sozialen Entwicklung. Die Umsetzung erfordert einen soliden Überprüfungsmechanismus. Dieser soll durch eine regemäßige nationale Erfassung von ca. 200 definierten UN-SDG-Indikatoren erfolgen, mit dem Ziel Fortschritte zu monitoren und die Politik zu informieren.

Effects of nurse tree species on growth, environment and physiology of underplanted Toona ciliata (F. Muell.)

Toona ciliata (Australian red cedar) is highly valued for veneer and furniture production and endangered in its natural ecosystems due to exploitation. This work aims to improve the availability of this wood on the market and help reduce pressure on the species in its native environment. An afforestation project cultivating Toona ciliata was introduced to the study site in Misiones, Argentina. The local cultivation faces losses caused by drought and frost, because T. ciliata requires overstory protection when young. Consequently, Grevillea robusta, Pinus elliottii x Pinus caribaea, and Pinus taeda, nurse tree species which also produce sought-after wood were chosen to provide protection. One-year-old T. ciliata seedlings were planted underneath each of the six-year-old nurse species. An inventory after one year indicated that both survival and height increment were highest underneath G. robusta and lowest underneath P. elliottii x P. caribaea. In this study I am examining possible facilitation and competition mechanisms between the overstory and understory T. ciliata. Extensive empirical data collected over the course of 3 years will be utilized to project potential growth scenarios for several rotations using a computer based forest growth model.

Fire, climate change and human impact in tropical ecosystems: paleoecological insights from the East African region

Fire is an important ecological factor of disturbance in African tropical ecosystems, driving vegetation dynamics and regulating nutrient cycling and biomass. The significance of wildfires for future environmental processes is underlined by recent projections of global warming, which predict more frequent and more intense extremes of natural events. Particularly in East Africa, where population growth and natural resource exploitation are among the highest in the world, strategies for sustainable economic development will have to deal with environmental changes at regional to continental scales. Understanding such complex responses to global change requires long-term records, since only they provide a way to observe the response of ecosystems to large-magnitude environmental change on decadal and longer time scales. We use high-resolution charcoal data from lake-sediment cores to reconstruct past fire/climate/human interactions in East Africa, aiming in particular 1) to understand how the fire regime influenced vegetation dynamics during the last millennia in savannah-type and sub-humid tropical ecosystems, 2) to test whether changes in fire regime are coupled with episodes of past climatic extremes inferred from the available sedimentological data, and 3) to detect early human deforestation and the timing of increased fire frequencies beyond its natural variability. Additionally, we will apply novel techniques such as molecular markers (benzene polycarboxylic acids, BPCAs) to complement the standard sedimentary approaches to reconstruct Holocene fire history. The proposed research addresses new, highly relevant questions for today's key issue of sustainability (economic development, natural resource management, adaptation of vulnerable communities to global change). Additionally, it will contribute with new high-quality data to ongoing multi-proxy research concerning the magnitude, frequency, and rates of past climate change in equatorial East Africa. Finally, the project will contribute to our understanding of tropical ecosystem functioning and its interaction with regional, cultural, and economic systems.

Polygeneration through gasification utilising secondary fuels derived from MSW (POLYSTABILAT)

Objective: In Osnabruck, Germany, Herhof Recyclingcenter Osnabrueck GmbH (HRO) operates, under patented technology (biological drying), a 90.000 tons/a Municipal Solid Wastes (MSW) recycling plant, where appr. 50Prozent of incoming MSW (45.000 tons/a) is converted into a secondary fuel (marketed under the name Stabilat), currently used in cement plants. A portion of Stabilat (appr. 500 kg/h) will be converted to electricity and heat in a novel gasification plant. The producer gas (LCV 5 MJ/Nm3) will be cleaned in a novel high temperature gas filter and combusted in a gas boiler, the steam generated to run a 0,5 MWe steam turbine. The electricity produced will be fed in the Grid, while waste heat will be utilised in the recycling plant. The off-gases from gas boiler and the liquid effluents (tars and oxygenates) will be guided to the recycling plant waste treatmen systems, while the inert ash will be incorporated in the residues resulting from the operation of the recycling plant. The integrated facility (MSW recycling and energy exploitation of Stabilat) will provide a sustainable solution for the treatment of MSW and will generate renewable energy, and a high quality fuel while safeguarding the environment and the public health. This innovative integration of state-of-the-art technologies has a large potential for duplication in the EU and beyond, achieving the disposal not only of the MSW but also of the resulting by-product streams (such as RDF or SRF fuels). Moreover, the proposed project addresses several EU policies related to renewable energies, energy efficiency, environmental protection, recycling of MSW, etc. Moreover, the coupling of the MSW recycling and the subsequent energy exloitation of by-products streams to electricity and heat will result in significant economies of scale. This, in turn, will result in positive synergistic effects (lower emissions of pollutants, elimination of the need to transport secondary fuels over long distances, reduced capital and operating costs and increased competitiveness).

FP6-SUSTDEV, European Seas Observatory NETwork (ESONET)

The aim of ESONET is to create an organisation capable of implementing, operating and maintaining a network of ocean observatories in deep waters around Europe from the Arctic Ocean to the Black Sea connected to shore with data and power links via fibre optic cables. The fundamental scientific objective is to make continuous real-time observations of environmental variables over decadal, annual, seasonal, diel and tidal time scales. Constant vigilance will allow resolution of quasi-instantaneous hazardous events such as slides, earthquakes, tsunamis and benthic storms. ESONET will form a sub sea segment of the GMES (Global Monitoring for Environment and Security) with sensors extending from the sub sea floor, through the water column to sub-surface sensors providing calibration of satellite borne sensors. ESONET brings together leading oceanographic and geosciences institutes in Europe together with universities, industry and regional agencies. It will provide integration across disciplines from geosciences, through physical, chemical and biological oceanography to technologies of instrumentation, cables, data processing and archiving. Jointly executed research will demonstrate functioning observatories at several cabled and non-cabled sites around Europe. Existing deep-sea cables installed for neutrino telescopes will be utilised in the Mediterranean sea and shallower tests sites will be established elsewhere. Principles of sensor management, calibration, metadata and data quality will be established with real-time dissemination and generation of hazard warning. ESONET will run a training and education program through courses, scholarships, exchange of personnel between participating institutes, and outreach to the general public. Dissemination will also include a web portal, with links to the INSPIRE Geo-Portal, and with all sub sea observatory projects worldwide, enabling the widest possible access to information. Prime Contractor: Institut Francais de Recherche pour l'Exploitation de la Mer; Issy-les-Moulineaux; France.

Belowground niche separation and competition in tree species mixtures

Root competition for water and nutrient among species is an ubiquitous feature of terrestrial plant communities influencing abundance and distribution of plants and the dynamics of their communities. The relationship between biodiversity and ecosystem functioning has emerged as a central issue in ecological and environmental sciences. It is commonly believed that increasing species richness increases the stability of communities. Higher plant species diversity might lead to increased exploitation of spatially heterogeneous resources by spatial niche complementarity. Tree species mixtures are generally believed to enhance ecosystem functioning in forests by niche partitioning and complementary resource exploitation due to differences in tree height, crown form, root depth and/ or phenology. In the past, however, most studies focused on the aboveground interaction and coexistence of the tree species, while factors controlling belowground species interactions remain less clear. There is experimental evidence to suggest that below-ground competition in herbaceous communities is size-symmetric in homogeneous soil. However, recent studies in tree communities indicate that fine-root competition may be asymmetric. The main purpose of this project is to characterize the underground niche separation and competition in relation to tree species diversity in mixtures comprising spruce, beech, oak and Douglas fir. Structural traits and spatial distribution of fine roots were investigated using a soil core method and fine-root growth is being assessed using the ingrowth core technique at a site in Kaltenborn, which is part of the long-term biodiversity-ecosystem functioning experiment with tree species of temperate forests (BIOTREE). The objectives of this study were to test the following hypotheses: (1) overall level of soil exploitation increases with the tree species diversity; (2) competitive ability belowground is size-symmetric, and (3) the below-ground competitive ability is species specific. As part of this investigation, we will explore the potential of using Near-infrared reflectance spectroscopy to identify the species identity of fine roots of the different tree species and to quantify the contribution of different fine roots in mixed root samples.

Developing strategies for application of resampling techniques in QTL mapping experiments with non-random populations

The dissection of complex traits into their underlying genetic components has become a major research area in plant breeding. As a consequence, significant progress has been made in the development of biometric methods for quantitative trait locus (QTL) analysis. Experimental studies on detection, mapping and unbiased estimation of QTL effects are generally performed on randomly derived progenies. For efficient integration of marker-assisted selection into classical breeding programs it seems indispensable to minimize expenditures by using selected populations for QTL detection. Thus, the development of new theoretical concepts for unbiased estimation of QTL effects in non-random populations is the focus of this study. Combining available QTL mapping methods, quantitative genetics, computer simulations, and analysis of experimental data, our goals are to develop biometric methods to apply QTL mapping and resampling techniques to non-random breeding populations such as Advanced-Backcross-populations (AB-QTL) or populations subjected to selection to obtain unbiased estimates of QTL effects and to allow full exploitation of the potential of marker-assisted selection. Our investigations will provide valuable analysis tools for optimizing marker-assisted selection programs. Furthermore, we aim to make recommendations on the integration of QTL analyses into practical breeding programs. Owing to the cooperative effort of research groups from Germany, Australia and the USA we expect that our results will be broadly distributed to the scientific community and practical plant breeding.

6. RP Aquaterra - Understanding river-sediment-soil-groundwater interactions for support of management of waterbodies (river basin & catchment areas) (AQUATERRA)

Objective: Changes in climatic conditions, land use practices and soil and sediment pollution have large-scale adverse impacts on water quantity and quality. The current knowledge base in river basin management is not adequate to deal with these impacts. Austere is both integrating and developing knowledge to resolve this and disseminating it to stakeholders. In the water cycle, soil is a key element affecting groundwater recharge and the chemical composition of both subsurface and surface waters (the latter is additionally affected by sediments). The proper functioning of the river-sediment-soil-groundwater system is linked to key biogeochemical processes determining the filter, buffer and transformation capacity of soils and sediments. Austere aims at a better understanding of the system as a whole by identifying relevant processes, quantifying the associated parameters and developing numerical models of the groundwater-soil-sediment-river system to identify adverse trends in soil functioning, water quantity and quality. The modelling addresses all relevant scales starting from micro-scale water/solid interactions, the transport of dissolved species, pollutants as well as suspended matter in soil and groundwater systems at the catchments scale, and finally the regional scale, with case studies located in major river basins in Europe. With this integrated modelling system, Austere provides the basis for improved river basin management, enhanced soil and groundwater monitoring programs and the early identification and forecasting of impacts on water quantity and quality during this century. Austere is committed to the dissemination and exploitation of project results through structured workshops, dedicated short courses, and the active participation of consortium partners in national and international conferences. A peer review panel supervises the quality and direction of the project.

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