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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.

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.

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.

Light in - Light out

Mankind is approaching a crisis in energy generation and utilization. Traditional fossil fuel reserves are diminishing and legislative issues regarding CO2 emission will make use of existing lower grade reserves unattractive. New technologies have to be developed to satisfy the ever-increasing energy demand and to maximize efficient energy usage. The materials chemist, through the design of new materials with novel properties and by controlling interfacial interactions between materials, will play a crucial role in these endeavours and in enabling the paradigm shift that is required. This project is centred around two core and inter-related issues (i) energy generation from photovoltaics using sunlight and (ii) efficient lighting devices based on light-emitting electrochemical cells (LECs) and organic light emitting diodes (OLEDs). Both of these topics are areas of intense activity world-wide. Within Europe the PIs research group is one of the leaders in the field. However, as research efforts in these areas are proving successful and proof-ofprinciple systems are being established and optimized, a new factor needs to be addressed. State of the art photovoltaic devices based upon the dye-sensitized solar cell (DSC) most frequently utilize inorganic dyes comprising ruthenium complexes of oligopyridine ligands. The projected next generation mass market OLEDs and prototype LECs are based upon iridium complexes containing cyclometallated pyridine ligands. A traditional criticism of these approaches related to the costs of the raw materials although this is in reality low compared to the costs of other components. However, the price reflects in part the availability of these metals and in this respect devices based upon ruthenium (1 ppb by atom in Earth crust) or iridium (0.05 ppb by atom in Earth crust) are unsustainable. This project is concerned with the development of complexes based upon abundant and sustainable first row transition metals to replace second and third row transition metals in these devices. Initial efforts will centre upon complexes of copper(I) and zinc(II) which have well-established photochemistry and photophysics making them suitable for such applications. The PI has already established proof-of-principle for the replacement of ruthenium by copper in DSCs and is a world leader in this technology. The work on the two projects will involve (i) materials synthesis and characterization (ii) computational modelling (iii) device construction and testing and (iv) property optimization.

Assessment of satellite constellations for monitoring the variations in earth s gravity field

More than a decade has passed since the launch of the GRACE satellite mission. Although designed for a nominal mission lifetime of 5 years, it still provides valuable science data. An eventual systems failure and, thus, mission termination is expected any time soon, though. Despite a relative low spatial and temporal resolution, the monthly gravity fields have proved an invaluable and novel parameter set in several geoscience disciplines, allowing new research venues in the study of Global Change phenomena. The hydrological cycle is now subject to quantification at continental scales; the state of the cryosphere, particularly ice sheet melting over Greenland and Antarctica, can be monitored; and steric effects of sea-level change have become separable from non-steric ones. The enormous success of the mission has driven the need for continuation of monitoring mass changes in the Earth system. Indeed, a GRACE Follow-On (GFO) mission has been approved for launch in August 2017. Like its predecessor it will consist of two satellites flying en echelon with intersatellite K-Band ranging as the main gravitational sensor. Despite a number of planned technological improvements, including a laser link as demonstrator, GFO will mostly be based on GRACE heritage. Given a similar orbit configuration and a similar systems setup, the quality of eventual gravity field products can be expected to be in the same range as the current GRACE products. To guarantee the continuation of such successful gravity field time series ESA has embarked several years ago on a long term strategy for future gravity field satellite missions, both in terms of technology development and in terms of consolidating the user community. Scientists from academia and industry held a workshop on The Future of Satellite Gravimetry at ESTEC premises, 12-13 April 2007, (RD-9). Similar workshops have been organized by other organizations, e.g. the joint GGOS/IGCP565 workshop Towards a Roadmap for Future Satellite Gravity Missions in Graz, September 30 - October 2, 2009. ESA furthermore played a key role in consolidating the international user community by funding a series of study projects, cf. (RD-1) to (RD-5). Similar projects have been funded and conducted at national level, e.g. the German BMBF-funded Geotechnologies III project Concepts for future gravity field satellite missions (PI: N. Sneeuw). These studies, together with GRACE experience, have provided a clear understanding of the current limitations of a GRACE-type mission. In particular the limitations in sampling and sensitivity of a single pair of satellites with in-orbit in-line sensitivity are well documented. At the same time, these studies have shown the design options and a roadmap towards a next generation gravity field mission.

FP6-SUSTDEV, Global Earth Observation - Benefit Estimation: Now, Next and Emerging (GEO-BENE): Conceptual Models for the Role and Benefits of EO and Modelling

Background: We investigate the role of future learning about the climate system (by global earth observation and modelling) and about climate thresholds in timing abatement policies. Learning plays a crucial role when irreversibilities or rigidities and large uncertainties are present in the system as in the case of climate change. For computational reasons most multi-stage models have simplified the learning process to an autonomous, perfect one-time learning. We focus on the implications of sequential, potentially active resolution of uncertainty in a simple multi-stage model with a climate threshold. Thereby, the concept of 'value of information' and 'future value of information' can be extended to the value of different sequential learning processes. Thereby, it is hoped to gain qualitative insights into questions like: How do first period optimal decisions with anticipated sequential learning compare to decisions for one-time learning? What is the benefit from resolving uncertainties over time in terms of improved abatement policy? What would the value of tipping point early warning systems be? How does this value depend on the flexibility in abatement and on other system properties? When is anticipation of learning essential? Method: (Approximate) stochastic dynamic programming. Results: In a first step, the probably simplest sequential decision model possible representing irreversibility, time-lags and a threshold (modified version of the model presented in Maddison(1995)) was used to gain first insights into the questions above. Learning was represented in a simple parametrized form taken from Kolstad (1996) and modified to represent active learning. Besides the sunk-cost - climate-irreversibility trade-off well known from the literature, additional tradeoffs are observed between learning velocity and threshold location and impacts, and between learning velocity and flexibility in abatement. Whether there is a clear correspondence between one-time learning and sequential learning in terms of first period recommendations is yet to be determined.

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.

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.(...)

The sustainable freight railway: Designing the freight vehicle track system for higher delivered tonnage with improved availability at reduced cost (SUSTRAIL)

A sustainable and efficient freight transport in Europe plays a vital role in having a successful and competitive economy. Freight transport is expected to grow by some 50 % (in tonne-kilometres) by 2020. However rail has, in many areas, been displaced from a dominant position as road transport services have grown and developed in capability and levels of sophistication that have not been matched by rail service providers. SUSTRAIL aims to contribute to the rail freight system to allow it to regain position and market and the proposed solution is based on a combined improvement in both freight vehicle and track components in a holistic approach aimed at achieving a higher reliability and increased performance of the rail freight system as a whole and profitability for all the stakeholders. The SUSTRAIL integrated approach is based on innovations in rolling stock and freight vehicles (with a targeted increased in speed and axle-load) combined with innovations in the track components (for higher reliability and reduced maintenance), whose benefits to freight and passenger users (since mixed routes are considered) are quantified through the development of an appropriate business case with estimation of cost savings on a life cycle basis. In fact, a holistic approach to vehicle and track sustainability has to be taken, since improvements in track design and materials alone are not enough as demands on the rail system increase. Contributions from the different topic areas (vehicles, track, operations) will be demonstrated on real routes, offering geographic dispersion as well as differences in type, speed, and frequency of traffic. A strong multidisciplinary consortium committed to concrete actions aligned toward a common outcome has been grouped for the achievement of the challenging objectives of the project with a balanced combination of Infrastructure managers, freight operators and Industry, including Large and Small enterprises, with support from Academia.

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