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Coordination and administration of the priority programme SPP 1315 Biogeochemical Interfaces in Soil, Biotic and abiotic factors that dive the function of microbial communities at biogeochemical interfaces in different soils (BAMISO)

Biogeochemical interfaces shape microbial community function in soil. On the other hand microbial communities influence the properties of biogeochemical interfaces. Despite the importance of this interplay, basic understanding of the role of biogeochemical interfaces for microbial performance is still missing. We postulate that biogeochemical interfaces in soil are important for the formation of functional consortia of microorganisms, which are able to shape their own microenvironment and therefore influence the properties of interfaces in soil. Furthermore biogeochemical interfaces act as genetic memory of soils, as they can store DNA from dead microbes and protect it from degradation. We propose that for the formation of functional biogeochemical interfaces microbial dispersal (e.g. along fungal networks) in response to quality and quantity of bioavailable carbon and/or water availability plays a major role, as the development of functional guilds of microbes requires energy and depends on the redox state of the habitat.To address these questions, hexadecane degradation will be studied in differently developed artificial and natural soils. To answer the question on the role of carbon quantity and quality, experiments will be performed with and without litter material at different water contents of the soil. Experiments will be performed with intact soil columns as well as soil samples where the developed interface structure has been artificially destroyed. Molecular analysis of hexadecane degrading microbial communties will be done in vitro as well as in situ. The corresponding toolbox has been successfully developed in the first phase of the priority program including methods for genome, transcriptome and proteome analysis.

Flowering time, development and yield in oilseed rape (Brassica napus): Sequence diversity in regulatory genes

Flowering time (FTi) genes play a key role as regulators of complex gene expression networks, and the influence of these networks on other complex systems means that FTi gene expression triggers a cascade of regulatory effects with a broad global effect on plant development. Hence, allelic and expression differences in FTi genes can play a central role in phenotypic variation throughput the plant lifecycle. A prime example for this is found in Brassica napus, a phenotypically and genetically diverse species with enormous variation in vernalisation requirement and flowering traits. The species includes oilseed rape (canola), one of the most important oilseed crops worldwide. Previously we have identified QTL clusters related to plant development, seed yield and heterosis in winter oilseed rape that seem to be conserved in diverse genetic backgrounds. We suspect that these QTL are controlled by global regulatory genes that influence numerous traits at different developmental stages. Interestingly, many of the QTL clusters for yield and biomass heterosis appear to correspond to the positions of meta-QTL for FTi in spring-type and/or winter-type B. napus. Based on the hypothesis that diversity in FTi genes has a key influence on plant development and yield, the aim of this study is a detailed analysis of DNA sequence variation in regulatory FTi genes in B. napus, combined with an investigation of associations between FTi gene haplotypes, developmental traits, yield components and seed yield.

Late-Glacial and Holocene vegetational stability of southern South America

This project focuses on the long-term stability (or otherwise) of vegetation, based on a series of multi-proxy records in southern South America. We will build a network of sites suitable for high-resolution reconstructions of changes in vegetation since the Last Glacial Maximum, and use these to test a null hypothesis that changes in vegetation over the past 14,000 years are driven by internal dynamics rather than external forcing factors. The extent to which the null hypothesis can be falsified will reveal the degree to which we can expect to be able to predict how vegetation is affected by external events, including future climate change. The southern fringes of the South American landmass provide a rare opportunity to examine the development of moorland vegetation with sparse tree cover in a wet, cool temperate climate of the Southern Hemisphere. We present a record of changes in vegetation over the past 17,000 years, from a lake in extreme southern Chile (Isla Santa Inés, Magallanes region, 53°38.97S; 72°25.24W; Fontana, Bennett 2012: The Holocene), where human influence on vegetation is negligible. The western archipelago of Tierra del Fuego remained treeless for most of the Lateglacial period. Nothofagus may have survived the last glacial maximum at the eastern edge of the Magellan glaciers from where it spread southwestwards and established in the region at around 10,500 cal. yr BP. Nothofagus antarctica was likely the earlier colonizing tree in the western islands, followed shortly after by Nothofagus betuloides. At 9000 cal. yr BP moorland communities expanded at the expense of Nothofagus woodland. Simultaneously, Nothofagus species shifted to dominance of the evergreen Nothofagus betuloides and the Magellanic rain forest established in the region. Rapid and drastic vegetation changes occurred at 5200 cal. yr BP, after the Mt Burney MB2 eruption, including the expansion and establishment of Pilgerodendron uviferum and the development of mixed Nothofagus-Pilgerodendron-Drimys woodland. Scattered populations of Nothofagus, as they occur today in westernmost Tierra del Fuego may be a good analogue for Nothofagus populations during the Lateglacial in eastern sites. Climate, dispersal barriers and/or fire disturbance may have played a role controlling the postglacial spread of Nothofagus. Climate change during the Lateglacial and early Holocene was a prerequisite for the expansion of Nothofagus populations and may have controlled it at many sites in Tierra del Fuego. The delayed arrival at the site, with respect to the Holocene warming, may be due to dispersal barriers and/or fire disturbance at eastern sites, reducing the size of the source populations. The retreat of Nothofagus woodland after 9000 cal. yr BP may be due to competitive interactions with bog communities. Volcanic disturbance had a positive influence on the expansion of Pilgerodendron uviferum and facilitated the development of mixed Nothofagus-Pilgerodendron-Drimys woodland.

Development of an integrated forest carbon monitoring system with field sampling and remote sensing for tropical forests in Indonesia

Forests play a relevant role in mitigation of climate change. A major issue, however, is the scientifically well founded, transparent and verifyable monitoring of achievements in forest carbon sequestration through reduction of deforestation and forest degradation, and through fostering sustainable forest management. Monitoring is particularly difficult in diverse and inaccessible humid tropical forest areas. The proposed research will contribute to the improvement of forest carbon monitoring under the challenging conditions of humid tropical forests. Sample based field observations and model based biomass predictions will be linked to area-wide satellite remote sensing imagery (RapidEye) and to strip samples of LiDAR imagery. Techniques of linking these data sources will be further developed and analysed with respect to (1) precision of carbon estimation and (2) accuracy of carbon regionalization. The proposed project implies research on methodological improvements of both sample based forest inventories (resampling techniques for biomass, imputation of non-response) and remote sensing application to forest monitoring (regionalization, sample based application of LiDAR data). At the core of this research is the analysis of the error variance components that each data source brings into the system. Such error analysis will allow identifying optimal resource allocation for the efficient improvement of forest carbon monitoring systems.

Taxing Energy Use 2015

This report analyses the taxation of energy use in 41 countries, covering 80% of global energy use. It appears at a juncture when many countries struggle to sustain orreconnect with economic growth and face formidable fiscal consolidation challenges. At the same time, concerns over the very highhuman costs of air pollution are mounting and the urgency of acting to limit greenhouse gases isnow abundantly clear.Energy use is an important source of greenhouse gas emissions and of air pollution. It also is acritical input into production and consumption in modern economies. If deployed effectively, taxes onenergy use are a powerful tool to balance the benefits and costs of energy use. Energy use taxes canalso play a useful role in fiscal consolidation. What this report tells us, however, is that with currentpolicies energy taxes fail to live up to their potential.Taxes on energy use influence the price and use of energy. Ideally, end-user energy prices wouldreflect their environmental impacts to ensure that resources are used most productively and that thenegative side-effects of energy use are contained. Taxes can help to achieve this, while also providingincentives to seek alternative, cleaner technologies.To employ energy taxes more effectively, it is necessary to understand the signals they providein respect of energy use. This report systematically analyses the structure and level of energy taxesacross 41 countries: the OECD countries and seven selected partner economies (Argentina, Brazil,China, India, Indonesia, Russia and South Africa). Effective tax rates, expressed per unit of carbonand per unit of energy, are situated within the energy market structures and other pricing policies ineach country, allowing the price signals they send to be better understood.Our analysis highlights vastly different levels of energy use and taxation among these41 countries, but also some common patterns. Transport energy is typically taxed at higher ratesthan other forms of energy use whereas fuels for heating and process use or electricity generationare more likely to be untaxed or taxed at lower rates. Fuels used for similar purposes are often taxeddifferently, with low rates applying to some of the fuels most harmful for human health and theenvironment. Tax rates on coal are particularly low.The picture is not, however, entirely bleak. The awareness about the need to curb negative sideeffectsof energy use is rising on governments political agendas, with many, including the selectedpartner economies, reconsidering price signals and taxes on harmful forms of energy use andinvesting in renewable sources of energy. This report can serve as a reference for policy makers andanalysts to identify reform options to ensure that energy taxes are best adapted to their economic,social and environmental goals - that is, to develop better tax policies for better lives.

Omongwa Pan, Namibia (June 2015) - an EnMAP Preparatory Flight Campaign

The dataset is composed of Neo HySpex (VNIR/SWIR) hyperspectral imagery acquired during airplane overflights on June 6th, 2015 covering the Omongwa Pan located in the South-West Kalahari, Namibia. The dataset includes three cloud-free flight lines with 408 spectral bands ranging from VNIR to SWIR wavelength regions (0.4-2.5 µm). The dataset also includes Level 2A EnMAP-like imagery simulated using the end-to-end Simulation tool (EeteS). The overall goal of the campaign was to acquire imagery over the Omongwa Pan and use the spectral reflectance for the analyses of surface sediments, specifically the mineralogical composition of exposed surface evaporites / salts on the airborne and spaceborne scale. The data are highly novel and can be used to test estimation of surface sediment properties in a highly saline and dynamic environment.

Water Harvesting for Rainfed Africa: investing in dryland agriculture for growth and resilience (WAHARA)

Objective: WAHARA will take a transdisciplinary approach to develop innovative, locally adapted water harvesting solutions with wider relevance for rain-fed Africa. Water harvesting technologies play a key role in bringing about an urgently needed increase in agricultural productivity, and to improve food and water security in rural areas. Water harvesting technologies enhance water buffering capacity, contributing to the resilience of African dry lands to climate variability and climate change, as well as to socio-economic changes such as population growth and urbanisation. To ensure the continental relevance of project results, research will concentrate on four geographically dispersed study sites in Tunisia, Burkina Faso, Ethiopia and Zambia, covering diverse socio-economic conditions and a range from arid to sub-humid climates. The project emphasizes: i) participatory technology design, i.e. selecting and adapting technologies that have synergies with existing farming systems and that are preferred by local stakeholders, yet tap from a global repertoire of innovative options; ii) sustainable impact, i.e. technologies that combine multiple uses of water, green and blue water management, and integrated water and nutrient management. Using models, water harvesting systems will be designed for maximum impact without compromising downstream water-users, contributing to sustainable regional development; iii) integration and adaptability, i.e. paying attention to the generic lessons to be learned from local experiences, and developing guidelines on how technologies can be adapted to different conditions; and iv) learning and action, i.e. a strategy will be developed to enable learning and action from successes achieved locally: a. within a region, to upscale from water harvesting technologies to water harvesting systems, and b. across regions, promoting knowledge exchange at continental scale.

Hydrologic Prediction in Alpine Environments II

Proposed research: This research programme proposes to analyze the predictability of the hydrologic behaviour of Alpine ecosystems at the spatio-temporal scales relevant for water management, i.e. at spatial scales of between 200 km2 (e.g. a hydropower production catchment) and around 5000 km2 (e.g. flood management of the Swiss Rhone catchment) and at temporal scales ranging from hours to seasons. Research context: Quantitative stream flow predictions are essential for the sustainable management of our natural and man-made environment and for the prevention of natural hazards. Despite of ever better insights into the involved physical processes at the point scale, many existing catchment scale runoff prediction models still show a lack of reliability for stream flow prediction. The present research programme addresses this foremost issue in Alpine environments, which are the source of many major European rivers and play a dominant role for hydropower production and flood protection. Stream flow prediction in such environments is particularly challenging due to the high spatial variability of the meteorological driving forces opposed to notorious data scarcity in remote and high elevation areas. Project context: The present proposal is a follow-up proposal of the Ambizione project Hydrologic Prediction in Alpine Environments. During the main phase of the project (3 years), certain essential research objectives could not be reached, due namely to the maternity leave of the principal investigator (PI), but also due to additional research questions that emerged at the very beginning of this research. The present follow-up project proposes to complete the research programme during a complementary project phase (2 years). Objectives: The main objective of this research programme is to assess under which conditions simple hydrological models can give reliable stream flow predictions in Alpine environments. This objective will be reached based on an analysis of the variability of natural flow generation processes and of the variability of corresponding state-of-the-art hydrological model outputs. During the main phase of the project, the research was concentrated on the analysis of flow generation processes related to snowmelt, which in Alpine areas dominate the hydrological response over a large part of the year. The achieved results include a new hourly snowmelt model combined to a spatially-explicit precipitation-runoff model, an improved snowfall-limit prediction method for hydrological models and a weather generator that produces coupled temperature and prediction scenarios to analyze how these two meteorological variables integrate to the snow-hydrological response.(...)

How does the future climate affects water quality in lake geneva? from understanding to predicting phytoplankton and nutrients trough an integrative modeling approach

Lakes can be considered as sentinels and thus indicators and integrators of environmental pressures such as climate change. To maintain lakes in a healthy ecological state is nowadays a major task for water management authorities, and will be increasingly so under climate change which is believed to negatively affect lake ecosystem functioning. Phytoplankton plays a key role in lake dynamics as it is at the base of the food web, and changes in its community have potential to affect the entire lake ecosystem. In addition, Cyanobacteria, the only freshwater phytoplankton group that is able to produce cyanotoxins, are capable of inflicting considerable harm to lake ecosystems and to human health through contamination of drinking water supply and toxin accumulation in fishes. Phytoplankton is thus a common indicator to assess the ecological status of lakes. Without understanding the complex mechanisms and processes that underlay a lake ecosystem in a changing climate, planning for future lake management and adaptation will be compromised. Numerical deterministic modelling is today the most appropriate approach to address these global and complex mechanistic features of lake ecosystems. Modeling studies play a key role in exploring the processes responsible for changes since they can be used to test the sensitivity of lakes to both observed and projected changes in climate. The aim of this project is to apply an ecological model to Lake Geneva, which has not been undertaken yet. Lake Geneva, a deep sub-Alpine lake, is the largest lake in central Europe and an essential source of drinking water, having not only a high ecological value, but also economic and social values. Due to its considerable environmental importance, it is crucial to assess, through numerical modeling techniques applied, how the Lakes water quality may be impaired; especially in view of the fact the observed rate of warming since 1900 is more than double that of the observed global average. Moreover, the hydrodynamic characteristics of Lake Geneva, the watershed of its most important inflow river Rhône, as well as the regional climate, have already been modeled. In coupling these models together, we will close the essential gaps, through which we will be able to understand the links between climate, watersheds, and lakes and provide a whole, integrated ecosystem perspective. This integrative model will provide an accurate predictive management tool to help take decisions and response strategies in a timely manner. It is generally recognized that future climate change will have an important impact on Lake Geneva, with a likely deterioration of its water quality. This will be manifested by high phosphorus concentrations, by phytoplankton biomass increase, by a change in phytoplankton composition, by an asynchronous phenology and by an emergence of potentially toxic Cyanobacteria.(...)

Production of activated clays for low-cost building materials in developing countries

Building Materials are a basic need, which is often difficult to meet in developing countries. Concrete is the building material best suited to meet these demands, although cement, the central ingredient is often disproportionately expensive in developing counties. The most promising option to lower costs (and environmental impact) is to blend conventional Portland cement with pozzolanic materials. The aim of this project is to develop technologies appropriate for the small scale, local production of pozzolans from clay (a material widely available) in conjunction with the exploitation of waste biomass for combined heat and power production. The modular concept of a clay activation unit, CAU to be coupled with a biomass boiler, will give the flexibility to adapt the solution to local conditions. We have already demonstrated that relatively common (low grade) clayey soils can be activated to give a pozzolan similar in performance to fly ash (from coal fired electricity production) widely used in the developed world. Results also indicate that it is possible to improve their reactivity by using and optimizing flash calcination, to allow high levels of substitution and very significant improvements in cost/performance ratio. To achieve this we need also to look at the performance of the activated clays in concrete from the point of view of rheology, hardening and durability to enable optimum cost/performance to be achieved according to local materials and applications. The partnership between LMC, EPFL and two academic groups in Cuba has already been established in a previous project. Furthermore, one of the Cuban partners plays a leading role in ECOSUR (a Swiss NGO) which has established workshops, producing low cost building materials, in many developing countries. In the first part of the project significant scientific advances were made, which enabled a huge acceleration in progress, relative to previous work by the Cuban partners alone. In addition, 3 Cuban PhD students spent several months working in the Swiss laboratory and have now returned to Cuba to continue their research. In this project, funding is requested for one PhD student to be based in Switzerland, who will work closely with 3 Cuban PhD Student (funded be the Cuban government). On the Cuban side, funds are requested for essential equipment and to fund the stays of the students at EPFL. Each of the Cuban students will spend 4-8 months working at EPFL during the course of the project.

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