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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.

Flood risk in a changing climate (CEDIM)

Aims: Floods in small and medium-sized river catchments have often been a focus of attention in the past. In contrast to large rivers like the Rhine, the Elbe or the Danube, discharge can increase very rapidly in such catchments; we are thus confronted with a high damage potential combined with almost no time for advance warning. Since the heavy precipitation events causing such floods are often spatially very limited, they are difficult to forecast; long-term provision is therefore an important task, which makes it necessary to identify vulnerable regions and to develop prevention measures. For that purpose, one needs to know how the frequency and the intensity of floods will develop in the future, especially in the near future, i.e. the next few decades. Besides providing such prognoses, an important goal of this project was also to quantify their uncertainty. Method: These questions were studied by a team of meteorologists and hydrologists from KIT and GFZ. They simulated the natural chain 'large-scale weather - regional precipitation - catchment discharge' by a model chain 'global climate model (GCM) - regional climate model (RCM) - hydrological model (HM)'. As a novel feature, we performed so-called ensemble simulations in order to estimate the range of possible results, i.e. the uncertainty: we used two GCMs with different realizations, two RCMs and three HMs. The ensemble method, which is quite standard in physics, engineering and recently also in weather forecasting has hitherto rarely been used in regional climate modeling due to the very high computational demands. In our study, the demand was even higher due to the high spatial resolution (7 km by 7 km) we used; presently, regional studies use considerably larger grid boxes of about 100 km2. However, our study shows that a high resolution is necessary for a realistic simulation of the small-scale rainfall patterns and intensities. This combination of high resolution and an ensemble using results from global, regional and hydrological models is unique. Results: By way of example, we considered the low-mountain range rivers Mulde and Ruhr and the more alpine Ammer river in this study, all of which had severe flood events in the past. Our study confirms that heavy precipitation events will occur more frequently in the future. Does this also entail an increased flood risk? Our results indicate that in any case, the risk will not decrease. However, each catchment reacts differently, and different models may produce different precipitation and runoff regimes, emphasizing the need of ensemble studies. A statistically significant increase of floods is expected for the river Ruhr in winter and in summer. For the river Mulde, we observe a slight increase of floods during summer and autumn, and for the river Ammer a slight decrease in summer and a slight increase in winter.

Untersuchungen des Tagesgangs verschiedener Spurengase mit Hilfe der solaren Absorptionsspektroskopie im infraroten Spektralbereich im tropischen Westpazifik (TROPAC)

Der Ozean im Westpazifik ist mit Temperaturen von ganzjährig 30°C der wärmste Ozean der Welt. Im tropischen Westpazifik ist die Lufttemperatur der Grenzschicht weltweit am höchsten und die Ozonkonzentration am niedrigsten. Aufgrund der allgemeinen Advektion der Luftmassen in der unteren und mittleren Troposphäre aus dem Osten durch die Walker-Zirkulation über den Pazifik befindet sich die Luft über dem tropischen Westpazifik für längere Zeit in einer sauberen, warmen und feuchten Umgebung. Der Abbau von reaktiven Sauerstoff- und Ozonvorläufern wie NOx findet daher länger als anderswo in den Tropen, was zu sehr niedrigen Ozonkonzentrationen führte. Dies erhöht die Lebensdauer von kurzlebigen biogenen und anthropogenen Spurengasen. Darüber hinaus begünstigen hohe Meeresoberflächentemperaturen eine starke Konvektion im tropischen Westpazifik, was zu niedrigen Ozonmischungsverhältnissen in den konvektiven Ausflussgebieten in der oberen Troposphäre führen kann. Der Warmpool im Westpazifik ist auch eine wichtige Quellregion für stratosphärische Luft. Daher fallen die Region, in der die Lebensdauer kurzlebiger Spurengase erhöht ist, und die Quellregion der stratosphärischen Luft zusammen. Somit bestimmt die Zusammensetzung der troposphärischen Atmosphäre in dieser Region in hohem Maße auch die globale stratosphärische Zusammensetzung.Ozon ist aufgrund von Rückkopplungsprozessen zwischen Temperatur, Dynamik und Ozon ein wichtiges Spurengas in der Klimaforschung. Da der Warmpool im Westpazifik die Hauptquellenregion für stratosphärische Luft ist, ist die Kenntnis von Ozon und anderen kurzlebigen Spurengasen auch wichtig, um den Transport von Spurengasen in die Stratosphäre zu verstehen.Ziel unseres Projektes ist die Messung des Tagesgangs von Ozon und anderen Spurengasen mit Hilfe der hochauflösenden solaren Absorptions-FTIR-Spektroskopie. Die Messungen liefern die Gesamtsäulendichten von bis zu 20 Spurengasen. Für einige Spurengase erlaubt die Analyse der Spektrallinienform die Ableitung der Konzentrationsprofile in bis zu etwa vier atmosphärischen Höhenschichten. Ergänzt werden die Beobachtungen durch Ozonballonsondierungen, kontinuierliche Messungen der UV-Strahlung, und Modellrechnungen mit einem Chemie-Transport-Modell. Die Messungen sind für den Zeitraum August bis Oktober 2022 geplant, die Auswertung und Interpretation von November 2022 bis Januar 2023.

EcoTopTen 2.0 - promotion of energy efficient products and energy savings with market overviews, social-media activities and campaigns

Goal of the project EcoTopTen 2.0 is increasing the supply and demand for highly energy-efficient ecological products and to motivate consumers through targeted Actions, to reduce greenhouse gas emissions and to relieve the environment. Importantelements are the regular update of EcoTopTen market overviews, cooperations with retailers, the action 'Save 1000 kWh', as well as accompanying social media activities.

Vegetation dynamics following forest stand destruction by snow avalange in the Berchtesgaden National Park

On 18 Januar 1986 at the east-looking slope of the Kleiner Watzmann in the Berchtesgaden National Park a snow avalanche came down from an elevation of about 2.000 m to the Königssee near St. Bartholomae (610 m above see level). It destroyed 12 to 15 ha of old growth forests dominated by beech (Fagus sylvatica); about 2.000 m3 of wood were thrown down. The soil survace was not intensively effected by the snow avalange. Because the area is situated in the central protection zone of the national park no clearing procedure was done, and a free stand develeopment without any direct impact of man is allowed to take place. In 1989 permanent plots (3 transects, each starting in the surrounding forest and crossing to avalanche area) were established. Vegetation and stand structure records were carried out in 1989, 1994 and 1999. Vegetation development in the first place is characterised by (1) a re-establishment of the tree layer by the (beech) trees, which were bent to the ground but not killed by the avalanche, (2) by seedling and sapling establishment (especially Acer and Fraxinus, but not by pioneer trees) and (3) by continuing floristic composition of the ground vegetation (coverage increasing or decresing depending on the light conditions).

Informationen zur Beschreibung des Genmaterials, zur Langzeitlagerung und Vermehrung der eingelagerten Muster, zur Vermittlung und zum Austausch des Genmaterials einschl. Kartoffeln

a) Erfassung, Speicherung und Wiedergewinnung der relevanten Informationen aus den unter 130 genannten Arbeitsbereichen der Genbank. b) Bereitstellung von Informationen, um die Vermittlung gewuenschten Genmaterials zu ermoeglichen bzw. zu erleichtern sowie die Unterlagen fuer die Arbeitsablaeufe der anderen Genbankabteilungen verfuegbar zu machen. c) Eingabe und Speichern der gesammelten und aufbereiteten Informationen ueber das elektronische Datenbanksystem. Ausdrucken der nach den entsprechenden Deskriptoren mit Deskriptorwerten abgerufenen Genmateriallisten. Herausgabe entsprechender Publikationen (Genbank-Informationsdienst); langfristig.

Brutbiologische Untersuchungen und Bestandsaufnahme an Singvoegeln an der dem MPIV Seewiesen angeschlossenen Vogelwarte Radolfzell

Mit Hilfe der Nestersuche werden auf Probeflaechen brutbiologische und populationsdynamische Daten erfasst, die in sogenannte Nestkarten eingetragen werden.

Gefrierkonservierung von Fischsperma

Gefrierkonservierungen wurden bisher nur bei wenigen Fischarten erfolgreich durchgefuehrt. Weiterentwicklung der Methoden ist notwendig. Ziel: Schaffung praxisreifer Methoden zur Anwendung bei der kontrollierten Vermehrung von Fischen. Methoden: Konservierung in Fluessigstickstoff.

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

Linking soil architecture formation with changing permafrost regime to carbon turnover in high latitude soils at multiple spatial scales

Most soils develop distinct soil architecture during pedogenesis and soil organic carbon (SOC) is sequestered within a hierarchical system of mineral-organic associations and aggregates. Permafrost soils store large amounts of carbon due to their permanently frozen subsoil and a lack of oxygen in the active layer, but they lack complex soil structure. With permafrost thaw more oxidative conditions and increasing soil temperature presumably enhance the build-up of more complex units of soil architecture and may counterbalance, at least partly, SOC mineralization. We aim to explore the development of mineral-organic associations and aggregates under different permafrost impact with respect to SOC stabilization. This information will be linked to environmental control factors relevant for SOC turnover at the pedon and stand scale to bridge processes occurring at the aggregate scale to larger spatial dimensions. We will combine in situ spectroscopic techniques with fractionation approaches and identify mechanisms relevant for SOC turnover at different scales by multivariate statistics and variogram analyses. From this we expect a deeper knowledge about soil architecture formation in the transition of permafrost soils to terrestrial soils and a scale-spanning mechanistic understanding of SOC cycling in permafrost regions.

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