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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.
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 (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.
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.
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.
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.
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.
Objective: The CONVERGE project will build from the concept of 'contraction and convergence' that informed the Kyoto process. C&C linked the key social concept of equal rights to emissions with the key ecological need for reduced emissions to issue a challenge to economic systems to develop fair processes for emissions reduction. CONVERGE aims to re-think globalisation by developing our understanding of convergence beyond emissions-trading across wider social, economic and ecological dimensions of sustainability. CONVERGE will research, develop and test the processes of contraction, convergence and divergence in current forms of globalisation. The research will be based on systems science to integrate social, scientific and economic disciplines in order to create coherent solutions to complex problems. Key to the success of this study is the interdisciplinary approach and working with stakeholders from civil society, government and business. CONVERGE seeks to explore convergent sustainability relationships across different scales from local, national, global-regional to global. CONVERGE will research current examples of convergence in communities, policies and indicators moving towards sustainability. The project will develop a convergence frame for understanding and development in civil society and policy communities; accessible publications providing guidance and tools for the use of this framework; a set of Convergence indicators, quantitative and qualitative, that will be used to test and model the processes of convergence including development of a Computer Programme; and recommendations to assist policy makers to integrate C&C into the decision making process. CONVERGE will play a significant role in achieving the strategic objective of EUs global partnership: 'to promote sustainable development actively worldwide and ensure that the European Union's internal and external policies are consistent with global sustainable development and its international commitments.'
The presence of endolithic growth of pro- and eukaryotic algae in light penetrated rock parts is a common phenomenon of arid/semi-arid landscapes world wide. While endolithic communities from Antarctic sandstones are well described, our knowledge of these communities inside granite and calcite is sparse. During the field campaign 2002/2003, we found that endolithic cyanobacterial growth is much more common than previously thought in the Dry Valleys of Antarctica. 41 and 50 mg chlorophyll a/m2 were determined in calcite and granite, respectively. Bonani et al. (1988) determined an age in Beacon sandstone in the order of magnitude of 103 years. However, we determined an age of ca70 years for the granite communities. Although age measurements can only be a guess, concluded from our results, productivity must be by far higher than expected. Water is the limiting factor and we hypothesize, that in addition to snow melt, condensation by temperature reversal of substratum and air is a frequent water supply. Reports about endolithic communities in the rocks of Arctic Greenland are, to our knowledge, limited to the fossil record. A first rock sample from Greenland revealed a luxuriantly growing cryptoendolithic community dominated by green algae. We will characterize them in detail in this project. Bioalkalization due to photosynthetic activity of cyanobacteria plays a major role in the weathering of silicate rocks in the tropics and shall be another major topic here.
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