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Forest functions arrangement with the CBD's Ecosystem Approach - A study on the Bengawan Solo River Basin, Java, Indonesia

The natural capital of forests consists to a great extend of the forests environmental functions for human well-being, which not only include goods and services (source and sink functions) but also include life-support functions that reflect ecosystem performance (ecosystem functioning). Shifting the management approach from a traditional one to one that is more aware of the ecosystem complexity, the idea of 'ecosystem functioning is appearing to tackle gradual declines of ecosystem functions. Within CBDs framework, the Ecosystem Approach has been introduced on account of the necessity for open decision making with strong links between all stakeholders and the latest scientific knowledge due to uncertainty and unpredictability in nature. The Ecosystem Approach is still in need of further elaboration, even though as a concept Ecosystem Approach has been widely accepted. To aim forest enhancement, this approach has been regarded as the most feasible concept for the study area, the Bengawan Solo River Basin - Java, Indonesia. Therefore the principles and operational guidelines will be used to analyse and evaluate the current forest management in those areas of the Bengawan Solo River Basin, in which ecosystem function is the basis for forest development area. This research focuses on ecological functions of forests at various levels of ecosystem management planning, from the forestry sectors point of view.

International Collaboration in Chemistry: First Principles Multi-Lattice Kinetic Monte Carlo Simulations of NOx Storage Reduction Catalysts

The broad objective of the research is to gain a fundamental understanding of the surface reaction chemistry of exhaust catalysts operating under cycling conditions. Using an integrated theoretical approach we specifically target NOx abatement, with particular emphasis on the appearance and destruction of surface oxide phases as the reactor conditions cycle from oxidative to reductive during the operation of the NOx Storage Reduction (NSR) catalyst system. Methodologically this requires material-specific, quantitative and explicitly time-dependent simulation tools that can follow the evolution of the system over the macroscopic time-scales of NSR cycles, while simultaneously accounting for the atomic-scale site heterogeneity and spatial distributions at the evolving surface. To meet these challenging demands we will develop a novel multi-scale methodology relying on a multi-lattice first-principles kinetic Monte Carlo (kMC) approach. As representative example the simulations will be carried out on a PdO(101)/Pd(100) surface oxide model, but care will be taken to ensure a generalization of the multi-lattice first-principles kMC approach to other systems in which phase transformations may occur and result in a change in the surface lattice structure depending upon environmental variables.

First-principles kinetic modeling for solar hydrogen production

The development of sustainable and efficient energy conversion processes at interfaces is at the center of the rapidly growing field of basic energy science. How successful this challenge can be addressed will ultimately depend on the acquired degree of molecular-level understanding. In this respect, the severe knowledge gap in electro- or photocatalytic conversions compared to corresponding thermal processes in heterogeneous catalysis is staggering. This discrepancy is most blatant in the present status of predictive-quality, viz. first-principles based modelling in the two fields, which largely owes to multifactorial methodological issues connected with the treatment of the electrochemical environment and the description of the surface redox chemistry driven by the photo-excited charges or external potentials.Successfully tackling these complexities will advance modelling methodology in (photo)electrocatalysis to a similar level as already established in heterogeneous catalysis, with an impact that likely even supersedes the one seen there in the last decade. A corresponding method development is the core objective of the present proposal, with particular emphasis on numerically efficient approaches that will ultimately allow to reach comprehensive microkinetic formulations. Synergistically combining the methodological expertise of the two participating groups we specifically aim to implement and advance implicit and mixed implicit/explicit solvation models, as well as QM/MM approaches to describe energy-related processes at solid-liquid interfaces. With the clear objective to develop general-purpose methodology we will illustrate their use with applications to hydrogen generation through water splitting. Disentangling the electro- resp. photocatalytic effect with respect to the corresponding dark reaction, this concerns both the hydrogen evolution reaction at metal electrodes like Pt and direct water splitting at oxide photocatalysts like TiO2. Through this we expect to arrive at a detailed mechanistic understanding that will culminate in the formulation of comprehensive microkinetic models of the light- or potential-driven redox process. Evaluating these models with kinetic Monte Carlo simulations will unambiguously identify the rate-determining and overpotential-creating steps and therewith provide the basis for a rational optimization of the overall process. As such our study will provide a key example of how systematic method development in computational approaches to basic energy sciences leads to breakthrough progress and serves both fundamental understanding and cutting-edge application.

Sustainable Water Resources Management in the Yanqi Basin, Sinkiang, China

Irrigation in the Yanqi Basin, Sinkiang, China has led to water table rise and soil salination. A model is used to assess management options. These include more irrigation with groundwater, water saving irrigation techniques and others. The model relies on input data from remote sensing.The Yanqi Basin is located in the north-western Chinese province of Xinjiang.This agriculturally highly productive region is heavily irrigated with water drawn from the Kaidu River. The Kaidu River itself is mainly fed by snow and glacier melt from the Tian Mountain surrounding the basin. A very poor drainage system and an overexploitation of surface water have lead to a series of environmental problems: 1. Seepage water under irrigated fields has raised the groundwater table during the last years, causing strongly increased groundwater evaporation. The salt dissolved in the groundwater accumulates at the soil surface as the groundwater evaporates. This soil salinization leads to degradation of vegetation as well as to a loss of arable farmland. 2. The runoff from the Bostan Lake to the downstream Corridor is limited since large amount of water is used for irrigation in the Yanqi Basin. Nowadays, the runoff is maintained by pumping water from the lake to the river. The environmental and ecological system is facing a serious threat.In order to improve the situation in the Yanqi Basin, a jointly funded cooperation has been set up by the Institute of Environmental Engineering, Swiss Federal Institute of Technology (ETH) , China Institute of Geological and Environmental Monitoring (CIGEM) and Xinjiang Agricultural University. The situation could in principle be improved by using groundwater for irrigation, thus lowering the groundwater table and saving unproductive evaporation. However, this is associated with higher cost as groundwater has to be pumped. The major decision variable to steer the system into a desirable state is thus the ratio of irrigation water pumped from the aquifer and irrigation water drawn from the river. The basis to evaluate the ideal ratio between river and groundwater - applied to irrigation - will be a groundwater model combined with models describing the processes of the unsaturated zone. The project will focus on the following aspects of research: (...)

Alternative Gases for dielectric insulation

Introduction: The United Nations Framework Convention on Climate Change classified SF6 as greenhouse gas, and the Annex I countries are obliged to publish the inventory of SF6 and to reduce emissions. However, survey data show an increasing concentration of SF6 (1), and recent evaluations demonstrate that only 30 Prozent of SF6 emissions are reported (2). Novel regulations and technical development must aim at decreasing SF6 emissions below the natural decomposition rate. For dielectric insulation applications, i.e. in situations where discharges are exceptional, it might be possible to replace SF6 by a different gas or gas mixture. No alternative gas is established, despite an extensive study of the dielectric strength of electron attaching gases in the past (3), (4). As many of the well investigated gases are covered by the Kyoto protocol, new options must be provided by fundamental research. In the present research project, the dielectric strength of alternative gases will be evaluated. There is general agreement, that mixtures of two or more gases are most suitable for replacing SF6 in dielectric insulation applications. Due to 'synergistic effects' the dielectric strength of a mixture can be higher than of pure gases (5), or at least the dielectric strength of a mixture can be higher than the linear combination of the strength of the constituents (6). Various types of synergistic effects have so far been described on the basis of the electron velocity distribution function or on the basis of ion-neutral collisions. Methods: The methods developed for investigating electron attaching gases may be classified to three groups: Phenomenological, macroscopic and microscopic methods. The research strategy of the project at hand is a combination of two established methods. In a Pulsed Townsend Discharge (PTD) experiment the macroscopic parameters of electron-ion swarms in attaching gases are measured. Synergistic effects in gas mixtures will be investigated microscopically by Monte Carlo (MC) simulations. The PTD is a traditional method and considerable experience has been gained at the HVL during the years 1980-1990 (7,8). The group of de Urquijo (Mexico) lately used a PTD for studying the alternative gas CF3I (9). In figure 1 the principle of the PTD setup is given. The swarm parameters are obtained from a fit of the analytical expression of the displacement current to the recorded current. Refer to (10) for more details on our swarm parameter experiment SParX. Recently satisfying agreement was achieved between MC simulations and data from PTD experiments (11, 12). The critical issue of these simulations is the availability of a consistent set of cross sections of electron-neutral and ion-neutral collisions. In the present study the output of SParX serves for calibrating the cross sections and the simulations. usw.

Monitoring changes in biodiversity at regional and continental scales over the past three decades using a dynamic habitat index derived from historical satellite data

Understanding the drivers behind the loss of biodiversity currently observed is of major importance in the context of the global change discussion. For studies of biodiversity at broad spatial scales, satellite remote sensing is the premier source of information, as it is uniquely capable of covering large areas of the Earth at high temporal resolution. The underlying assumption is that satellite-derived geophysical surface parameters, such as vegetation greenness, are related to biodiversity. For that purpose, concepts such as the Dynamic Habitat Index (DHI) were recently developed. The DHI combines information on the overall greenness, the base level of vegetation cover, and vegetation seasonality at a certain location. By comparing the annual DHI with a long term mean, areas undergoing disturbances or recovery events can be delineated, which are indicative of changes in species composition and diversity. The concept of the DHI was developed for data obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) post-2000. However, for climate change impact studies a longer time series is desirable. The only sensor system suitable for such applications is the Advanced Very High Resolution Radiometer (AVHRR), which has been in orbit on various platforms since the early 1980ies. The purpose of this project was to develop a methodology to derive long term information on habitat conditions at continental scales based on historical satellite data. In particular, the goal was to adopt the principle of the DHI as developed for the MODIS sensor to an AVHRR archive at 1 km spatial resolution over Canada and to analyze long term variations in the DHI. In a first project phase, an AVHRR data set of vegetation greenness, generated in the framework of the project, was validated against the reference MODIS product. The results demonstrated a very good agreement between both data sets for a wide range of vegetation types and on various spatial and temporal scales. A historical baseline of habitat conditions post-1987 based on the DHI was subsequently generated based on the long term AVHRR data. The analysis of the DHI showed that certain areas, particularly northern parts of the Province of Quebec as well as southwestern Canada, experienced significant changes over the past two decades, which may have had significant impacts on species diversity and abundance in these areas. In the future, the methods developed in the framework of this project may be used to obtain information on long term variations in habitat conditions in areas covered by other historical satellite archives, e.g., for Europe based on an AVHRR archive hosted at the University of Bern.

Calcium cycle for efficient and low cost CO2 capture in fluidized bed systems (C3-CAPTURE)

Objectives: The project aims on developing a dry CO2 capture system for atmospheric and pressurized fluidized bed boilers. The atmospheric option will be developed towards a pilot plant application. For the pressurized option the project seeks for a proof of principle to determine if the advantages of a pressurized capture system can balance the problems known from existing PFBC systems. The quantifiable objectives are: - Low CO2 capture costs (less than 20 Euro/t for atmospheric, less than 12 Euro/t for pressurized sy stems) - Acceptable efficiency penalty for CO2 capture (less than about equal to 6 percent nel). - greater than 90 percent carbon capture for new power plants and greater than 60 percent for retrofitted existing plants - A purge gas stream containing greater than 95 percent CO2 - A solid purge usable for cement production - Sim ultaneous sulphur and CO2 removal with sulphur recovery option Approach: Limestone is a CO2 carrier. The CO2 can be released easily in a conventional calcination process, well known in the cement and lime industry. By integrating a closed carbonation/calc ination loop in the flue gas of a conventional CFB-boiler, the CO2 in the flue gas can be removed. The heat required for calcination is released during carbonation and can be utilised efficiently (high temperature) in the steam cycle of the boiler. Concent rated CO2 can be generated when using oxygen blown calcination. Because the fuel required for supplying heat for calcination is only a fraction of the total fuel requirements, the required oxygen is only about 1/3 of the oxygen required for oxyfuel process es. The work programme: 1.Definition of the technical and economic boundary conditions 2.Selection and improvement of sorbent materials 3.Lab scale and semi-technical scale process development (experimental work) 4.Technical and economic evaluation 5.Des ign of a 1 MWth Pilot plant.

Development of guidance for establishing Integrated Pest Management (IPM) principles

Integratives nachhaltiges Wildtier-management im Biosphärenpark Wienerwald

Wildtiere (Arten, Populationen, Individuen, Lebensräume, genetische Vielfalt) werden neben der Jagd von vielen anderen Landnutzungsaktivitäten beeinflusst, die sich im Wildlebensraum vielfach überlagern und oftmals miteinander konkurrieren. Insbesondere in Mehrfachnutzungs-Kulturlandschaften, wie dem Biosphärenpark Wienerwald, können die resultierenden Wechselwirkungen zwischen den Lebensraumansprüchen von Wildtieren, jagdlichen Nutzungsinteressen und anderen Landnutzungsansprüchen oftmals zu Konflikten führen, die der nachhaltigen Erhaltung heimischer Wildtierarten und ihrer Lebensräume, der Nachhaltigkeit der beteiligten Landnutzungen und einer nachhaltigen regionalen Entwicklung insgesamt abträglich sein können. Sektorale Nachhaltigkeitsansätze alleine sind unzureichend und können sogar unbeabsichtigte negative Auswirkungen auf andere Landnutzungen und auf das betreffende Ökosystem haben. Der nachhaltige Umgang mit Wildtieren kann letztlich nur gelingen, wenn alle im Wildlebensraum agierenden Nutzergruppen sich der Auswirkungen ihrer Tätigkeiten auf die Ressource 'Wildtier' sowie auf die jeweils anderen Nutzergruppen bewusst sind. Am Beispiel von 'Wildtieren und Jagd' wurden daher im Biosphärenpark Wienerwald modellhaft Konzepte, Inhalte und Instrumente für eine integrative, d. h. sektorübergreifend abgestimmte Nachhaltigkeitsbeurteilung mehrerer Landnutzergruppen entwickelt. Mittels angewandter und partizipativer Forschungsmethoden (Experteninterviews, breite Nutzerbefragungen, projektbegleitende Partizipation) wurden zentrale Schnittstellen (Antagonismen, Synergiepotenziale) zwischen Wildtieren, Jagd und weiteren regionalen Landnutzungen identifiziert, analysiert und bewertet. Als zentrales Ergebnis liegen sektorübergreifend abgestimmte Sets von Prinzipien, Kriterien und Indikatoren für ein integratives nachhaltiges Wildtiermanagement im Biosphärenpark Wienerwald vor. Die Bewertungssets dienen der Selbstbewertung wesentlicher regionaler Nutzergruppen (Forstwirtschaft, Landwirtschaft, Jagd, Freizeit- und Erholungsmanagement) und ermöglichen es diesen, jeweils eigene Einflussmöglichkeiten auf die nachhaltige Erhaltung von Wildtierarten, deren Lebensräumen und eine nachhaltige Jagd selbst zu überprüfen. Nachhaltigkeitsanforderungen anderer Nutzergruppen wurden dabei jeweils berücksichtigt. Somit wurde am Beispiel der stark vernetzten Thematik 'Umgang mit Wildtieren' erstmals der Schritt von der rein sektorbezogenen hin zu einer sektorübergreifend abgestimmten Erfassung der Nachhaltigkeit vollzogen. Weiters wurden Empfehlungen für ein integratives nachhaltiges Wildtiermanagement sowie für ein diesbezügliches Monitoring ausgearbeitet. Die Projektergebnisse sollen dazu beitragen, Wildtiere und deren Management möglichst konfliktfrei in eine nachhaltige Landnutzung im Biosphärenpark Wienerwald zu integrieren. Die Vollversion des Endberichtes samt Anhängen ist als Download-Publikation auf der Homepage der Österreichischen Akademie der Wissenschaften

Energy and Water Fluxes at the Soil Atmosphere Interface of Water Repellent soils

Water repellency (WR) plays a significant role in a large number of soils all over the world. In many regions global warming will lead to drier land surfaces and thus, increasing the likeliness of actual water repellency for such soils. The hydrological effects of WR (surface runoff, water erosion, preferential flow) have been relatively well investigated in the last decades. However, its effect on the energy balance between soil and atmosphere has not been studied yet. We postulate that global warming does not only lead to an increase in WR of soils, but WR has an impact on the energy balance and thus, will lead to a feedback on global warming. In order to test our hypothesis, we want to determine all components of the energy- and water balance between soil and atmosphere for a strongly water repellent soil. As a reference we want to repeat the same measurements for the same soil, at which the WR has been suspended by application of a surfactants. While the laboratory studies aim to give insight into more principle processes, the lysimeter (bare and with plants) and field scale studies shall give information about integrated complex natural processes. The gained knowledge shall be implemented into a numerical simulation tool for modeling water and energy balances in order to predict the effects of WR under different atmospheric conditions and physical soil properties.

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