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Natural Forest Management in Caracarai, Roraima, Brazil

Objectives: Sustainable management of tropical moist forests through private forest owners will become increasingly important. Media report that in Brazil, particularly in Amazonia, approx. 80 percent of the timber harvested is from illegal sources. Private management of forests according to internationally acknowledged standards offers an opportunity to significantly lower the portion of illegally cut timber. Moreover, it contributes significantly to the conservation of the Amazon forest. Private forest owners show a clear long-term commitment towards the implementation of management standards according that is ecologically compatible, socially acceptable and economically viable. The project area, a pristine forest in legal Amazonia in the transition zone between moist tropical forests and savannas (cerrado), is extremely diverse in floristic and faunistic terms. The institute cooperates with the private forest owner. Main tasks are to document the faunistic and floristic diversity, to calculate the Annual Allowable Cut and to elaborate concepts for site-specific silviculture. Results: To date (Oct. 2006) the following activities were started: - a comprehensive inventory system for planning at the FMU-level has been successfully introduced; - the inventory system for the annual coupe area has been designed and data for the first coupe are being processed; - the annual allowable cut is currently calculated based on the results of the above described inventories; - two fauna surveys are completed; one focusing on large mammals and one on the avi-fauna. A long-term monitoring concept to assess the influence of forest management on the faunistic diversity is currently under development; - forest zoning is completed applying terrestrial surveys and interpreting high-resolution satellite images; - a study on the use of Bethollethia excelsa-fruits (Brazil nuts) is currently implemented; - a study on timber properties of lesser known species is currently implemented.

Effect of agricultural intensification on cereal aphid-primary parasitoid-hyperparasitoid food web structures and interactions

Changes in agroecosystem management (e.g. landscape diversity, management intensity) affect the natural control of pests. The effects of agricultural change on this ecosystem service, however, are not universal and the mechanisms affecting it remain to be understood. As biological control is effectively the product of networks of interactions between pests and their natural enemies, food web analysis provides a versatile tool to address this gap of knowledge. The proposed project will utilize a molecular food web approach and examine, for the first time, how changes in plant fertilisation and landscape complexity affect quantitative aphid-parasitoid-hyperparasitoid food webs on a species-specific level to unravel how changes in food web interactions affect parasitoid aphid control. Based on the fieldderived data, cage experiments will be conducted to assess how parasitoid diversity and identity affect parasitoid interactions and pest control, complementing the field results. The work proposed here will take research on parasitoid aphid control one step further, as it will provide a clearer understanding of how plant fertilization affects whole aphid-parasitoid food webs in both simple and complex landscapes, allowing for further improvements in natural pest control.

Pollen and environmental reconstruction, Holocene dynamics of tropical rainforest, climate, fire, human impact and land use in Sulawesi and Sumatra, Indonesia

The present-day configuration of Indonesia and SE Asia is the results of a long history of tectonic movements, volcanisms and global eustatic sea-level changes. Not indifferent to these dynamics, fauna and flora have been evolving and dispersing following a complicate pattern of continent-sea changes to form what are today defined as Sundaland and Wallacea biogeographical regions. The modern intraannual climate of Indonesia is generally described as tropical, seasonally wet with seasonal reversals of prevailing low-level winds (Asian-Australian monsoon). However at the interannual scale a range of influences operating over varying time scales affect the local climate in respect of temporal and spatial distribution of rainfall. Vegetation generally reflects climate and to simplify it is possible to distinguish three main ecological elements in the flora of Malaysia: everwet tropical, seasonally dry tropical (monsoon) and montane. Within those major ecological groups, a wide range of specific local conditions caused a complex biogeography which has and still attract the attention of botanists and biogeographers worldwide. Being one of the richest regions in the Worlds in terms of species endemism and biodiversity, Indonesia has recently gone through intensive transformation of previously rural/natural lands for intensive agriculture (oil palm, rubber, cocoa plantations and rice fields). Climate change represents an additional stress. Projected climate changes in the region include strengthening of monsoon circulation and increase in the frequency and magnitude of extreme rainfall and drought events. The ecological consequences of these scenarios are hard to predict. Within the context of sustainable management of conservation areas and agro-landscapes, Holocene palaeoecological and palynological studies provide a valuable contribution by showing how the natural vegetation present at the location has changed as a consequence of climate variability in the long-term (e.g. the Mid-Holocene moisture maximum, the modern ENSO onset, Little Ice Age etc.). The final aim of my PhD research is to compare the Holocene history of Jambi province and Central Sulawesi. In particular: - Reconstructing past vegetation, plant diversity and climate dynamics in the two study areas Jambi (Sumatra) and Lore Lindu National Park (Sulawesi) - Comparing the ecological responses of lowland monsoon swampy rainforest (Sumatra) and everwet montane rainforests (Sulawesi) to environmental variability (vulnerability/resilience) - Investigating the history of human impact on the landscape (shifting cultivation, slash and burn, crop cultivation, rubber and palm oil plantation) - Assessing the impact and role of droughts (El Niño) and fires - Adding a historical perspective to the evaluation of current and future changes.

Biogeochemical interface formation in soils as controlled by different components

We consider clay minerals, iron oxides and charcoal as major components controlling the formation of interfaces relevant for sorption of organic chemicals, as they control the assemblage of organic matter and mineral particles. We studied the formation of interfaces in batch incubation experiments with inoculated artificial soils consisting of model compounds (clay minerals, iron oxide, char) and natural soil samples. Results show a relevant contribution of both iron oxides and clay minerals to the formation of organic matter as sorptive interfaces for hydrophobic compounds. Thus, we intend to focus our work in the second phase on the characterization of the interface as formed by organic matter associated with clay minerals and iron oxides. The interfaces will be characterized by the BET-N2 and ethylene glycol monoethyl ether (EGME) methods and 129Xe and 13C NMR spectroscopy for determination of specific surface area, sorptive domains in the organic matter and microporosity. A major step forward is expected by the analysis of the composition of the interface at different resolution by reflected-light microscopy (mm scale), SEM (scanning electron microscopy, micrometer scale) and secondary ion mass spectrometry at the nanometer scale (nanoSIMS). The outcomes obtained in combination with findings from cooperation partners will help to unravel the contribution of different types of soil components on the formation and characteristics of the biogeochemical interfaces and their effect on organic chemical sorption.

Forschergruppe (FOR) 1806: The Forgotten Part of Carbon Cycling: Organic Matter Storage and Turnover in Subsoils (SUBSOM), Biological Regulation of Subsoil C-cycling under Field Conditions

The nature of the microbial communities inhabiting the deeper soil horizons is largely unknown. It is also not clear why subsurface microorganisms do not make faster use of organic compounds under field conditions. The answer could be provided by a reciprocal soil transfer experiment studying the response of transferred soils to fluctuations in microclimate, organic inputs, and soil biota. The subproject P9 will be responsible for the establishment of reciprocal transfer experiments offering a strong link between subgroups interested in organic matter quality, transport of organic substances, as well as functions of the soil microbial community. A single, high molecular weight substrate (13C labelled cellulose) will be applied at two different levels in the pre-experiment to understand the dose-dependent reaction of soil microorganisms in transferred surface and sub-soils. Uniformly 13C labelled beech roots - representing complex substrates - will be used for the main reciprocal soil transfer experiment. We hypothesize that transferring soil cores between subsoil and surface soil as well as addition of labelled cellulose or roots will allow us to evaluate the relative impact of surface/subsurface habitat conditions and resource availability on abundance, function, and diversity of the soil microbial community. The second objective of the subproject is to understand whether minerals buried within different soil compartments (topsoil vs. subsoil) in the field contribute to creation of hot spots of microbial abundance and activity within a period of two to five years. We hypothesize that soil microorganisms colonize organo-mineral complexes depending on their nutritional composition and substrate availability. The existence of micro-habitat specific microbial communities could be important for short term carbon storage (1 to 6 years). The third objective is to understand the biogeography and function of soil microorganisms in different subsoils. Parent material as well as mineral composition might control niche differentiation during soil development. Depending on size and interconnectedness of niches, colonization and survival of soil microbial communities might be different in soils derived from loess, sand, terra fusca, or sandstone. From the methodological point of view, our specific interest is to place community composition into context with soil microbial functions in subsoils. Our subgroup will be responsible for determining the abundance, diversity, und function of soil microorganisms (13C microbial biomass, 13C PLFA, enzyme activities, DNA extraction followed by quantitative PCR). Quantitative PCR will be used to estimate total abundances of bacteria, archaea and fungi as well as abundances of specific groups of bacteria at high taxonomic levels. We will apply taxa specific bacterial primers because classes or phyla might be differentiated into ecological categories on the basis of their life strategies.

Drivers and mechanisms of 13C discrimination in Cleistogenes squarrosa (C4) - reducing uncertainties on bundle sheath leakiness

The energetic efficiency of C4 photosynthesis is strongly affected by bundle sheath leakiness, which is commonly assessed with the 'linear version' of the Farquhar model of 13C discrimination, and leaf gas exchange and 13C composition data. But, the linear Farquhar model is a simplification of the full mechanistic theory of ? in C4 plants, potentially generating errors in the estimation of leakiness. In particular, post-photosynthetic C isotope fractionation could cause large errors, but has not been studied in any detail. The present project aims to improve the understanding of the ecological and developmental/physiological factors controlling discrimination and leakiness of the perennial grass Cleistogenes squarrosa. C. squarrosa is the most important member of the C4 community which has spread significantly in the Mongolia grasslands in the last decades. It has an unusually high and variable discrimination, which suggests very high (and potentially highly variable) leakiness. Specifically, we will conduct the first systematic study of respiratory 13C fractionation in light and dark at leaf- and stand-scale in this C4 species, and assess its effect on discrimination and estimates of leakiness. These experiments are conducted in specialized 13CO2/12CO2 gas exchange mesocosms using ecologically relevant scenarios, testing specific hypotheses on effects of environmental drivers and plant and leaf developmental stage on discrimination and leakiness.

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.

Species discrimination of plant roots by Fourier transform infrared (FTIR) spectroscopy

Comprehension of belowground competition between plant species is a central part in understanding the complex interactions in intercropped agricultural systems, between crops and weeds as well as in natural ecosystems. So far, no simple and rapid method for species discrimination of roots in the soil exists. We will be developing a method for root discrimination of various species based on Fourier Transform Infrared (FTIR)-Attenuated Total Reflexion (ATR) Spectroscopy and expanding its application to the field. The absorbance patterns of FTIR-ATR spectra represent the chemical sample composition like an individual fingerprint. By means of multivariate methods, spectra will be grouped according to spectral and chemical similarity in order to achieve species discrimination. We will investigate pea and oat roots as well as maize and barnyard grass roots using various cultivars/proveniences grown in the greenhouse. Pea and oat are recommendable species for intercropping to achieve superior grain and protein yields in an environmentally sustainable manner. To evaluate the effects of intercropping on root distribution in the field, root segments will be measured directly at the soil profile wall using a mobile FTIR spectrometer. By extracting the main root compounds (lipids, proteins, carbohydrates) and recording their FTIR-ATR spectra as references, we will elucidate the chemical basis of species-specific differences.

Molecular determinants of host specificity of maize-, rice- and mango-pathogenic species of the genus Fusarium

Fusarium species of the Gibberella fujikuroi species complex cause serious diseases on different crops such as rice, wheat and maize. An important group of plant pathogens is the Gibberella fujikuroi species complex (GFC) of closely related Fusarium species which are associated with specific hosts; F. verticillioides and F. proliferatum are particularly associated with maize where they can cause serious ear-, root-, and stalk rot diseases. Two other closely related species of the GFC, F. mangiferae and F. fujikuroi, which share about 90Prozent sequence identity with F. verticillioides, are pathogens on mango and rice, respectively. All of these species produce a broad spectrum of secondary metabolites such as phytohormones (gibberellins, auxins, and cytokinins), and harmful mycotoxins, such as fumonisin, fusarin C, or fusaric acid in large quantities. However, the spectrum of those mycotoxins might differ between closely related species suggesting that secondary metabolites might be determinants for host specificity. In this project, we will study the potential impact of secondary metabolites (i.e. phytohormones and certain mycotoxins) and some other species-specific factors (e.g. species-specific transcription factors) on host specificity. The recently sequenced genomes of F. mangiferae and F. fujikuroi by our groups and the planned sequencing of F. proliferatum will help to identify such determinants by genetic manipulation of the appropriate metabolic pathway(s).

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

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