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Impact of Landscape Level Land Use Changes with Study Sites in Nicaragua

Das Projekt "Impact of Landscape Level Land Use Changes with Study Sites in Nicaragua" wird vom Umweltbundesamt gefördert und von Universität Göttingen, Burckhardt-Institut, Abteilung Waldinventur und Fernerkundung durchgeführt. The main cause of loss of natural resources in Central America is the advance of the agricultural border (UICN, 2001), demanding more land area to produce the same amount of food, as a consequence of the loss of the productive capacity of the ground and the decrease sources (García 2003), the traditional farming practices as crop in the zones of greater slopes, exaggerated use of agrochemical substances and overpasturing have caused negative impacts on the ecosystems (Córdoba, 2002). At the moment livestock is one of the activities of production that have the biggest share of the regions economy (ILRI, 2004), although at the same time it has been announced one of the main causes of the natural ecosystems transformation, provocing the loss of the agrosystems sustainability (Kaimowitz 1996). Taking into account that the systems of extensive production are coming along with the degradation of natural ressources that exist in the forest, an approach of new technics, that are compatible with livestock production and the conservation of natural ressources become necessary. One of these approaches is the introduction of Silvopastoral technologies (Ibrahim et al. 1999). SilvoPastoral Systems (SPS) constitute an alternative for cattle production, where wooded perennial (trees and/or shrubs) interact with the traditional components (herbaceous covers and animals) under a system of integral handling (Ibrahim, 1996). This is a system of sustainable production that, through transformations that improve the performance in production, generates environmental services when protecting and conserving the sources (Ibrahim et al. 2003). Objectives: Identify land use of SPS by analysing satellite imagery (Lansat TM/ ETM+ and Quickbird). Identify the contribution of SPS to the recovery of forestal coverage and the cabon stock in Nicaragua by the application of GIS (Geographic Informatic Systems). Determine the duration of the carbon fixation in SPS.

Effects of canopy structure on salinity stress in cucumber (Cucumis sativus L.)

Das Projekt "Effects of canopy structure on salinity stress in cucumber (Cucumis sativus L.)" wird vom Umweltbundesamt gefördert und von Hochschule Geisenheim University, Zentrum für Wein- und Gartenbau, Institut für Gemüsebau durchgeführt. Salinity reduces the productivity of cucumber (Cucumis sativus L.) through osmotic and ionic effects. For given atmospheric conditions we hypothesize the existence of an optimal canopy structure at which water use efficiency is maximal and salt accumulation per unit of dry matter production is minimal. This canopy structure optimum can be predicted by integrating physiological processes over the canopy using a functional-structural plant model (FSPM). This model needs to represent the influence of osmotic stress on plant morphology and stomatal conductance, the accumulation of toxic ions and their dynamics in the different compartments of the system, and their toxic effects in the leaf. Experiments will be conducted to parameterize an extended cucumber FSPM. In in-silico experiments with the FSPM we attempt to identify which canopy structure could lead to maximum long-term water use efficiency with minimum ionic stress. The results from in-silico experiments will be evaluated by comparing different canopy structures in greenhouses. Finally, the FSPM will be used to investigate to which extent the improvement of individual mechanisms of salt tolerance like reduced sensitivity of stomatal conductance or leaf expansion can contribute to whole-plant salt tolerance.

Effects of biochar amendment on plant growth, microbial communities and biochar decomposition in agricultural soils

Das Projekt "Effects of biochar amendment on plant growth, microbial communities and biochar decomposition in agricultural soils" wird vom Umweltbundesamt gefördert und von Forschungsinstitut für biologischen Landbau Deutschland e.V. durchgeführt. Biochar has a great potential to ameliorate arable soils, especially those that are low in organic matter due to intensive use or erosion. Biochar is carbonised organic material with high porosity that brings about changes in physical, chemical and biological soil functions. Biochar amended soils show a higher water and cation exchange capacity with reduced leaching and enhanced availability of plant nutrients. The microbial biomass in biochar amended soils is enhanced and more diverse. Biochar is stabilised organic material, which is likely to remain for hundreds of years in the soil. Photosynthetically fixed atmospheric CO2 stabilised in biochar may thus act as a direct carbon sink and help to mitigate climate change. As feedstock and production conditions produce different biochar qualities predictions of effects in soil need to consider biochar and soil properties case by case. To date biochar has been approved to ameliorate highly weathered tropical soils with positive effects on crop growth and yield. Distinct microbial groups were reported to be enhanced in soils but if this depends on the particular soil or biochar or a combination of both is an open question, especially in temperate climates. Likewise, it is not known if microorganisms colonising biochar surfaces are responsible for its mineralization or if they just use the new niches provided. The aim of the proposed project is to investigate the influence of two biochar types on soil-plant systems by determining i) soil nutrient availability, plant growth and nutrient uptake, ii) structure and function of soil microbial communities, iv) the decomposition and fate of biochar in soils. We will use two loessial soils from the well-known DOK-trial with different soil organic matter content. Other soils from the region will be selected to provide a wider range of soil quality, in particular pH. The biochars will be produced by pyrolysis and hydrothermal carbonization (HTC) from the C4-plant Miscanthus gigantea. Pyrolysis derived material has bigger pore sizes due to the evaporating gasses and is commonly alkaline, whereas the HTC derived biochar has a finer pore size, a much higher oxygen content and more acidic functional groups.

Upwind: Development of Improved Wind Turbine Noise Prediction Tools for Low Noise Airfoil Design

Das Projekt "Upwind: Development of Improved Wind Turbine Noise Prediction Tools for Low Noise Airfoil Design" wird vom Umweltbundesamt gefördert und von Universität Stuttgart, Institut für Aerodynamik und Gasdynamik durchgeführt. The noise regulations of various countries urge wind turbine manufacturers to reduce the aerodynamical noise emission of their turbines. To reduce the greenhouse gas emission, wind energy has been put in a very front position. EWEA estimates 12percent of worlds energy may come from wind turbines by the year 2020 (approx. 1,260,000 MW). This means wider deployment of wind turbines, at lower wind speed sites i.e. close to people & transmission lines. To reduce the transmission cost between production site and customer, onshore installations are still a cheaper solution. One of the biggest barriers for developing onshore turbines is the noise which has a negative impact on people's daily life. Thus, the goal of developing onshore wind turbines is to design silent wind turbines and silent wind farms and at the same time have a good aerodynamic efficiency. Noise emitted from an operating wind turbine can be divided into two parts, mechanical noise and flow induced noise. Mechanical noise can sufficiently be reduced by conventional engineering approaches but flow-induced noise is more complex and need more focus. The noise mechanisms associated with flow-induced noise emission have different sources. These are, inflow turbulence noise, tip noise, laminar boundary layer separation noise, blunt trailing-edge noise (BTE) and for turbulent boundary-layer trailing-edge interaction noise (TBL-TE). Acoustic field measurements within the European research project SIROCCO showed that the TBL-TE noise is the most dominant noise mechanism for modern wind turbines. Thus, accurate prediction and reduction of the TBL-TE noise is the main focus of the acoustics airfoil design methods for wind turbine rotor blade. For developing 'silent' airfoils, a routinely design fast, less expensive and accurate prediction methodology is desired. In this respect, simplified theoretical model would be the first candidate, and therefore the main goal is development of an accurate and efficient noise prediction model for the low noise wind turbine blade design.

Towards improved properties of biodegradable polymers made from Sugar Cane, PLA

Das Projekt "Towards improved properties of biodegradable polymers made from Sugar Cane, PLA" wird vom Umweltbundesamt gefördert und von Universität Halle-Wittenberg, Institut für Physik durchgeführt. In daily life, construction polymers play an important role. Most of products are not reusable for different reasons (cost, hygiene, ) so the need of an environment saving production and disposal is evident. To besides from the obvious task on saving resources and environment, there is also a growing economical interest in this issue. On of the most promising candidates for a thermoplastic construction polymer that can be manufactured from bio-renewable resources and is biodegradable is Polylactic acid (PLA), for which Corn starch (in the U.S.) or sugarcanes (rest of world) are the common feedstock. Polylactic acid can be processed like most thermoplastics into fiber (for example using conventional melt spinning processes) and film. However, the low glass transition temperature prohibits many applications, like usage for coffee cups that will simply soften and flow away upon filling with hot drinks. One popular option to cope with this is the modification with other polymers, either conventional product or even enantiomers of PLA itself. For example, the melting temperature can be increased 40-50 C and the Heat Deflection temperature of PLLA can be increased from approximately 60 C to up to 190 C for by physically blending the polymer with PDLA (poly-D-lactide). PDLA and PLLA are known to form a highly regular stereocomplex with increased crystallinity. The maximum effect in temperature stability is achieved when a 50-50 blend is used, but even at lower concentrations of 3-10Prozent of PDLA a substantial effect is achieved. In the latter case PDLA is used as a nucleating agent, thereby increasing the crystallization rate. Due to the higher crystallinity of this stereo-complex, the biodegradability will become slower. The interesting feature is that the polymer blend remains transparent, which is one to the desirable properties that must be kept upon modification.

MYFISH - Maximising yield of fisheries while balancing ecosystem, economic and social concerns

Das Projekt "MYFISH - Maximising yield of fisheries while balancing ecosystem, economic and social concerns" wird vom Umweltbundesamt gefördert und von Universität zu Kiel, Institut für Volkswirtschaftslehre, Lehrstuhl für Umwelt-, Ressourcen- und Ökologische Ökonomik durchgeführt. The MSY concept was included as a principle in the 2009 Green Paper on the reform of the Common Fisheries Policy (CFP) in accordance with the global imperative to manage fish stocks according to the maximum sustainable yield (MSY). This implies a commitment to direct management of fish stocks towards achieving MSY by 2015. Attaining this goal is complicated by the lack of common agreement on the interpretation of 'sustainability' and 'yield' and by the effects that achieving MSY for one stock may have on other stocks and broader ecosystem, economic, or social aspects. MYFISH will provide definitions of MSY variants which maximize other measures of 'yield' than biomass and which account for the fact that single species rarely exist in isolation. Further, MYFISH will redefine the term 'sustainable' to signify that Good Environmental Status (MSFD) is achieved and economically and socially unacceptable situations are avoided, all with acceptable levels of risk. In short, MYFISH aims at integrating the MSY concept with the overarching principals of the CFP: the precautionary and the ecosystem approach. MYFISH will achieve this objective through addressing fisheries in all RAC areas and integrating stakeholders (the fishing industry, NGOs and managers) throughout the project. Existing ecosystem and fisheries models will be modified to perform maximization of stakeholder approved yield measures while ensuring acceptable impact levels on ecosystem, economic and social aspects. Implementation plans are proposed and social aspects addressed through active involvement of stakeholders. Finally, effects of changes in environment, economy and society on MSY variants are considered, aiming at procedures rendering the MSY approach robust to such changes. The expertise of 26 partners from relevant disciplines including fisheries, ecosystem, economic and social science are involved in all aspects of the project. Global experience is engaged from North America and the South Pacific.

Late-Glacial and Holocene vegetational stability of southern South America

Das Projekt "Late-Glacial and Holocene vegetational stability of southern South America" wird vom Umweltbundesamt gefördert und von Universität Göttingen, Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Abteilung für Palynologie und Klimadynamik durchgeführt. 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.

Support to Member States in improving waste management based on assessment of Member States' performance

Das Projekt "Support to Member States in improving waste management based on assessment of Member States' performance" wird vom Umweltbundesamt gefördert und von BIPRO Beratungsgesellschaft für integrierte Problemlösungen GmbH durchgeführt. Implementation of EU waste legislation shows large differences in the EU Member States especially with regard to municipal waste management. Major discrepancies prevail particularly in the implementation and application of the Waste Framework Directive and proper transposition of EU requirements into national legislation. The waste management performance of all EU Member States was subject to screening to identify those Member States with the largest implementation gaps, in particular in relation to municipal waste management. For screening the main elements and legal requirements stemming from EU waste directives (mainly from the Waste Framework and the Landfill Directive) were considered for the design of suitable criteria. These core elements comprise the practical implementation of the waste management hierarchy, application of economic and legal instruments to move up the waste hierarchy, sufficiency of treatment infrastructure and quality of waste management planning, the fulfilment of targets and infringement procedures. These elements were assessed by 18 criteria for each Member State taking into account information sources at EU, national or regional level. Latest available statistical data and data of former years for comparison of development within a country were extracted from the EUROSTAT database. References comprised reports published by the European Commission, the European Topic Centre on Sustainable Consumption and Production, internal working documents of EUROSTAT and the EU Commission as well as national/regional Waste Management Plans. Where available also Waste Prevention Programmes were screened. The screening results confirmed the assumption of large differences within the EU-27 with regard to treatment of municipal waste, compliance with the WFD and Landfill Directives and application of legal or economic instruments as well as planning quality. For each criterion two, one or zero points could be achieved, leading to maximum points of 42 for all criteria. The methodology includes weighting of results for three selected criteria related to the application of the treatment options recycling, energy recovery and disposal of municipal waste.

Formation of mega-glendonites in the aftermath of the Paleocene-Eocene thermal maximum

Das Projekt "Formation of mega-glendonites in the aftermath of the Paleocene-Eocene thermal maximum" wird vom Umweltbundesamt gefördert und von Universität Münster, Institut für Geologie und Paläontologie durchgeführt. Glendonites are pseudomorphs after the mineral ikaite (CaCO3 x 6H2O) and composed of calcite (CaCO3). In the past, they have been used as a paleo-thermometer because the primary mineral ikaite, according to observations and experiments, seems to be formed at temperatures near freezing, high alkalinity and high phosphate concentrations in marine sediments. An enigmatic occurrence of the largest glendonites known world-wide, in the Early Eocene Fur Formation of northwestern Denmark offers the unique possibility to shed more light on the actual mechanism and controlling parameters of ikaite formation. Right in the aftermath of the Paleocene-Eocene thermal maximum, a time known for its global pertubation in the global carbon cycle, the formation of authigenic calcium carbonate concretions start in the Fur Formation. In a specific stratigraphic interval inbetween these concretions, the glendonites can be found. We will investigate if termperature changes or changes in geochemical parameters of the Danish Basin caused the sudden formation of ikaite during a time interval that was based on known paleoclimatic reconstructions (semi tropic) not favorable for ikaite formation.

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

Das Projekt "Holocene dynamics of tropical rainforest, climate, fire, human impact and land use in Sulawesi and Sumatra, Indonesia" wird vom Umweltbundesamt gefördert und von Universität Göttingen, Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Abteilung für Palynologie und Klimadynamik durchgeführt. 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.

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