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Palaeo-Evo-Devo of Malacostraca - a key to the evolutionary history of 'higher' crustaceans

In my project I aim at a better understanding of the evolution of malacostracan crustaceans, which includes very different groups such as mantis shrimps, krill and lobsters. Previous studies on Malacostraca, on extant as well as on fossil representatives, focussed on adult morphology.In contrast to such approaches, I will apply a Palaeo-Evo-Devo approach to shed new light on the evolution of Malacostraca. Palaeo-Evo-Devo uses data of different developmental stages of fossil malacostracan crustaceans, such as larval and juvenile stages. With this approach I aim at bridging morphological gaps between the different diverse lineages of modern malacostracans by providing new insights into the character evolution in these lineages.An extensive number of larval and juvenile malacostracans is present in the fossil record, but which have only scarcely been studied. The backbone of this project will be on malacostracans from the Solnhofen Lithographic Limestones (ca. 150 million years old), which are especially well preserved and exhibit minute details. During previous studies, I developed new documentation methods for tiny fossils from these deposits, e.g., fluorescence composite microscopy, and also discovered the first fossil mantis shrimp larvae. For malcostracan groups that do not occur in Solnhofen, I will investigate fossils from other lagerstätten, e.g., Mazon Creek and Bear Gulch (USA), or Montceaules- Mines and La-Voulte-sur-Rhône (France). The main groups in focus are mantis shrimps and certain other shrimps (e.g., mysids, caridoids), as well as the bottom-living ten-footed crustaceans (reptantians). Examples for studied structures are leg details, including the feeding apparatus, but also eyes. The results will contribute to the reconstruction of 3D computer models.The data collected in this project will be used for evaluating the relationships within Malacostraca, but mainly for providing plausible evolutionary scenarios, how the modern malacostracan diversity evolved. With the Palaeo-Evo-Devo approach, I am also able to detect shifts in developmental timing, called heterochrony, which is interpreted as one of the major driving forces of evolution. Finally, the reconstructed evolutionary patterns can be compared between the different lineages for convergencies. These comparisons might help to explain the convergent adaptation to similar ecological niches in different malacostracan groups, e.g., life in the deep sea, life on the sea bottom, evolution of metamorphosis or of predatory larvae.As the project requires the investigation of a large number of specimens in different groups, I will assign distinct sub-projects to three doctoral researchers. The results of this project will not only be published in peer-reviewed journals, but will also be presented to the non-scientific public, e.g., during fossil fairs or museum exhibitions with 3D models engraved in glass blocks.

Forschergruppe (FOR) 1320: Crop Sequence and Nutrient Acquisition from the Subsoil, Plant induced weathering of minerals in the subsoil - release of 'non-exchangeable' potassium from 2:1 layer minerals (TransMinK)

The proposal addresses the potential of subsoil to contribute to K nutrition of crops. More specifically we will address the processes controlling release of K from interlayer of 2:1 clay minerals as this is expected to be the dominant K fraction in the subsoil. While it has been shown in the past that this so called 'non-exchangeable' K can be released due to root activity, there are controversial results concerning the role of soil solution K concentration in the rhizosphere required to trigger the process. Likewise little information is available about the concentration dynamics of other cations (NH4, Ca) in the rhizosphere and their impact on K release and vermiculitization supposed to be associated with this process. Model studies with substrate from the central field trial will be conducted in compartment systems equipped with micro suction cups. The measurement of dynamic changes of soil solution composition with increasing distance from the root surface will be combined with investigations of changes in mineralogy by XRD, TEM and SEM-EDX. Changes of mineralogy as a result of plant induced K release from interlayer will also be studied on bulk soil and rhizosphere samples collected within the central field and the central microcosm experiment and with mineral bags exposed in the field during a cropping cycle. Finally, X-ray CT will be used to access changes in soil texture, i.e. clay distribution around roots and the temporal spread of roots in biopores which is a prerequisite for K uptake from such structures.

Rehabilitation of Degraded Forests in Yunnan (German-Chinese Cooperation for Agrarian Research)

Background: An increasing frequency of massive flooding along the lower Yangtse River in China ended in a disastrous catastrophe in summer 1998 leaving several thousand people homeless, more than 3.600 dead and causing enormous economic damage. Inappropriate land-use techniques and large scale timber felling in the water catchment of the upper Yangtse and its feeder streams were stated to be the main causes. Immediate timber cutting bans were imposed and investigations on land use patterns were initiated by the Chinese Government. The Institute for World Forestry of the Federal Research Centre for Forestry and Forest Products was approached by the Yunnan Academy of Forestry in Kunming to exchange experiences and to cooperate scientifically in the design and application of appropriate afforestation and silvicultural management techniques in the water catchment area of the Yangtse. This cooperation was initiated in 1999 and is based on formal agreements in the fields of agrarian research between the German and Chinese Governments. Objectives: The cooperation was in the first step focussing on the identification of factors which caused the enormous floodings. After their identification measures of prevention were determined and put into practice. In this context experiences made in past centuries in the alpine region of central Europe served as an incentive and example for similar environmental problems and solutions under comparable conditions. Relevant key questions of the cooperation project were: - Analysis of forest related factors influencing the recent floodings of the Yangtse, - Analysis and evaluation of silvicultural management experiences from central Europe for know-how transfer, - Evaluation of rehabilitation measures for successful application in Yunnan, - Dissemination of knowledge through vocational training. Results: - Frequent wild grazing of husbandry is a key factor for forest degeneration beyond unsustainable timber harvests, forest fires and insect calamities leading to increased water run-off in the mountainous region of Yunnan; - Browsing of cattle interrupts succession thus avoiding natural regeneration and leaving a logging ban ineffective; - Mountain pasture in the Alps had similar effects in the past in central Europe. The introduction of controlled grazing has led to an ecologically compatible coexistence of pasture and ecology. Close-to-nature forestry can have positive effects in this sensitive environment. - Afforestation with site adopted broadleaves and coniferous tree species was implemented on demonstration level using advanced techniques in Yunnan.

Das Energiewende-Szenario 2020 - Ausstieg aus der Atomenergie, Einstieg in Klimaschutz und nachhaltige Entwicklung

Water use characteristics of bamboo (South China)

Bamboos (Poaceae) are widespread in tropical and subtropical forests. Particularly in Asia, bamboos are cultivated by smallholders and increasingly in large plantations. In contrast to trees, reliable assessments of water use characteristics for bamboo are very scarce. Recently we tested a set of methods for assessing bamboo water use and obtained first results. Objectives of the proposed project are (1) to further test and develop the methods, (2) to compare the water use of different bamboo species, (3) to analyze the water use to bamboo size relationship across species, and (4) to assess effects of bamboo culm density on the stand-level transpiration. The study shall be conducted in South China where bamboos are very abundant. It is planned to work in a common garden (method testing), a botanical garden (species comparison, water use to size relationship), and on-farm (effects of culm density). Method testing will include a variety of approaches (thermal dissipation probes, stem heat balance, deuterium tracing and gravimetry), whereas subsequent steps will be based on thermal methods. The results may contribute to an improved understanding of bamboo water use characteristics and a more appropriate management of bamboo with respect to water resources.

Beach sand deposits on the coast of southern Norway as a natural experimental setup to test hypotheses on soil development and luminescence dating

Beach sand deposits are widespread in the area around Sandefjord, at the western coast of the Oslofjord, southern Norway. The age of the deposits continuously increases with elevation, as the area has been subject to steady glacio-isostatic uplift throughout the Holocene. Existing local sea level curves provide age control related to elevation. Thus, the area offers excellent conditions to test hypotheses on soil formation and OSL dating. A chronosequence covering the last 10 000 years will be established. A preliminary study showed that soil formation leads to Podzols within 4300 - 6600 years. Micromorphological analyses suggest that clay illuviation takes place before and below podzolisation. It is hypothesised that clay translocation goes on contemporarily with podzolisation, but at greater soil depth, where the chemical conditions are suitable. This hypothesis will be proved by more detailed micromorphological investigation and chemical analyses. The factors controlling soil forming processes and their rates, will be determined by analyzing elemental composition, primary minerals and clay mineralogy. Preliminary OSL dating tests suggest that the beach sand deposits are OSL dateable despite the high latitude. This hypothesis will be checked by comparing OSL datings to ages derived from the 14C-based sea level curves.

Variabilität des Ostasiatischen Monsuns während der letzten 65.000 Jahre - laminierte Seesedimente aus dem Sihailongwan-Maarsee, NE-China

Laminierte Seesedimente sind unschätzbare Informationsquellen zur Geschichte der Umwelt und des Klimas direkt aus der Lebenssphäre des Menschen. Ein exzellentes Beispiel dafür ist der Sihailongwan-Maarsee aus NE-China. In einem immer noch dicht bewaldeten Vulkangebiet gelegen, bieten seine Sedimente ein ungestörtes Abbild der Monsunvariationen über zehntausende von Jahren. Nur die letzten ca. 200 Jahre zeigen einen deutlichen lokalen anthropogenen Einfluss. Das Monsunklima der Region mit Hauptniederschlägen während des Sommers und extrem kalten Wintern unter dem Einfluss des Sibirischen Hochdrucksystems bildet die Voraussetzung für die Bildung von saisonal deutlich geschichteten Sedimenten (Warven), die in dem tiefen Maarsee dann auch überwiegend ungestört erhalten bleiben. Insbesondere die Auftauphase im Frühjahr bringt einen regelmässigen Sedimenteintrag in den See, der das Gerüst für eine derzeit bis 65.000 Jahre vor heute zurückreichende Warvenchronologie bildet. Für das letzte Glazial zeigen Pollenspektren aus dem Sihailongwan-Profil Vegetationsvariationen im Gleichklang mit bekannten klimatischen Variationen des zirkum-nordatlantischen Raumes (Dansgaard-Oeschger-Zyklen) zu dieser Zeit. Der Einfluss dieser Warmphasen auf das Ökosystem See war jedoch sehr unterschiedlich. So sind die Warven aus den Dansgaard-Oeschger (D/O) Zyklen 14 bis 17 mit extrem dicken Diatomeenlagen (hauptsächlich Stephanodiscus parvus/minutulus) denen vom Beginn der spätglazialen Erwärmung zum Verwechseln ähnlich, während Warven aus dem D/O-Zyklus 8 kaum Unterschiede zu überwiegend klastischen Warven aus kalten Interstadialen aufweisen. Gradierte Ereignislagen mit umgelagertem Bodenmaterial sind deutliche Hinweise auf ein Permafrost-Regime während der Kaltphasen. Auch während des Spätglazials treten deutliche klimatische Schwankungen auf, die der in europäischen Sedimentarchiven definierten Gerzensee-Oszillation und der Jüngeren Dryas zeitlich exakt entsprechen. Das frühe Holozän ist von einer Vielzahl Chinesischer Paläoklima-Archive als Phase mit intensiverem Sommermonsun bekannt. Überraschenderweise sind die minerogenen Fluxraten im Sihailongwan-See während des frühen Holozäns trotz dichter Bewaldung des Einzugsgebietes sehr hoch. Sowohl Mikrofaziesanalysen der Sedimente als auch geochemische Untersuchungen deuten auf remoten Staub als Ursache dieses verstärkten klastischen Eintrags hin. Der insbesondere in den letzten Jahrzehnten zunehmende Einfluss des Menschen zeigt sich in den Sedimenten des Sihailongwan-Maarsees vor allem in einem wiederum zunehmenden Staubeintrag und einer Versauerung im Einzugsgebiet. Der anthropogene Einflusss auf die lokale Vegetation ist immer noch gering.

CFK-Recycling in der Kompetenzregion Augsburg

The increasing proportion of carbon fibre reinforced plastics (CFRP) in different branches of industry will result in an increasingly larger quantity of CFRP wastes in future. With regard to improved management of natural resources, it is necessary to add these fibres that require energy-intensive production to effective recycling management. But high-quality material recycling is only ecoefficient if the recycled fibres can be used to produce new high-quality and marketable products. Tests carried out up to now indicate that very good results can be expected for large-scale recycling of carbon fibres by means of pyrolysis. The waste pyrolysis plant (WPP) operated in Burgau is the only large-scale pyrolysis plant for municipal wastes in Germany. Use of this plant to treat CFRP wastes represents a unique opportunity for the whole Southern German economy and in particular the Augsburg economic region. In a study funded by the Bavarian State Ministry of the Environment and Health ('Bayerisches Staatsministerium für Umwelt und Gesundheit'), the specific implementation options for the recovery of carbon fibres from composites by means of large-scale pyrolysis have been under investigation since November 2010. To this end, in the first step a development study was carried out, which in particular examined the options for modifying the Burgau WPP for the recycling of CFRP. The knowledge acquired from the pyrolysis tests, the fibre tests and the economic feasibility study confirmed the positive assessment of the overall concept of CFRP recycling in Burgau. As an overall result, unlimited profitability was found for all scenarios with regard to investments in CFRP recycling in Burgau WPP. The work on the development study was carried out by bifa Umweltinstitut GmbH together with the Augsburg-based 'function integrated lightweight construction project group ('Funktionsintegrierter Leichtbau' - FIL) of the Fraunhofer Institute for Chemical Technology (ICT). Methods: analysis and moderation of social processes, economy and management consulting, process engineering

The importance of peripheral oceanic processes in the Labrador Sea for the Atlantic meridional overturning circulation

The Labrador Sea is one of the few places in the world ocean, where deep water formation takes place. This water is exported from the Labrador Sea to become part of the southward branch of the meridional overturning circulation. Previous observational work has largely focused on the role of deep convection in the interior of the Labrador Sea. Recent evidence from observations and numerical ocean models specifically indicate that processes near the ocean boundaries might be most relevant for both Eulerian downwelling of waters in the Labrador Sea and the fast export of newly transformed waters. We propose to analyze mooring based observations at the western margin of the Labrador Sea together with high resolution numerical model simulations to understand the role both processes play for the meridional overturning circulation in the subpolar North Atlantic. Specifically, we want to test (i) if (and where) downwelling occurs along the margins of the Labrador Sea, (ii) how downwelling relates to the seasonal evolution of convection and eddy activity, (iii) how fast waters newly transformed near the western margin of the Labrador Sea are exported, and (iv) how the two processes (downwelling, fast export) affect the temporal variability of the Atlantic meridional overturning circulation.

Identification of groundwater nitrogen point source contribution through combined distribute temperature sensing and in-situ UV photometry

Agriculture is the major contributor of nitrogen to ecosystems, both by organic and inorganic fertilizers. Percolation of nitrate to groundwater and further transport to surface waters is assumed to be one of the major pathways in the fate of this nitrogen. The quantification of groundwater and associated nitrate flux to streams is still challenging. In particular because we lack understanding of the spatial distribution and temporal variability of groundwater and associated NO3- fluxes. In this preliminary study we will focus on the identification and quantification of groundwater and associated nitrate fluxes by combining high resolution distributed fiber-optic temperature sensing (DTS) with in situ UV photometry (ProPS). DTS is a new technique that is capable to measure temperature over distances of km with a spatial resolution of ca1 m and an accuracy of 0.01 K. It has been applied successfully to identify and quantify sources of groundwater discharge to streams. ProPS is a submersible UV process photometer, which uses high precision spectral analyses to provide single substance concentrations, in our case NO3-, at minute intervals and a detection limit of less than 0.05 mg l-1 (ca.0.01 mg NO3--Nl-1). We will conduct field experiments using artificial point sources of lateral inflow to test DTS and ProPS based quantification approaches and estimate their uncertainty. The selected study area is the Schwingbach catchment in Hessen, Germany, which has a good monitoring infrastructure. Preliminary research on hydrological fluxes and field observations indicate that the catchment favors the intended study.

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