Das Projekt "Plant-soil interactions in changing rice cropping systems and their influence on C and N dynamics" wird vom Umweltbundesamt gefördert und von Universität Bonn, Institut für Nutzpflanzenwissenschaften und Ressourcenschutz - Pflanzenernährung (Prof. Werner) durchgeführt. Plant-soil interactions drive the input, cycling and losses of C and N in soil. This subproject aims at elucidating the input and fate of C in the soil-plant systems and its effect of N retention in soil under different paddy management (continuous vs. alternating with maize cropping). In particular we will investigate (i) how much of the assimilate C is released by the plants into the rhizosphere soil, and how this rhizodeposition is affected by N supply, soil density and crop variety during plant development, (ii) how the exudation of C and N responds to land use change, (iii) how C released into the rhizosphere affects the turnover of soil C and utilization of fertilizer N, and (iv) to what degree leaching contributes to the loss of C and N from the rooted surface soil. To answer these questions, we will combine the use of isotopic 13C and 15N labeling in laboratory and field experiments with a sophisticated characterization of root exudates, root border cells, and compound-specific isotope tracing in the residues of bacteria and fungi in rhizosphere, bulk soil as well as within different dissolved organic and inorganic carbon species in soil leachates. In this way and in collaboration with SP 2, 5, 6, and 7 of this research unit, our project links the cycling of C and N in paddy soils to one of its most prominent drivers, the release of organic compounds by roots.
Das Projekt "Improvement of oil palm wood by bio resin application" wird vom Umweltbundesamt gefördert und von Technische Universität Dresden, Fachrichtung Forstwissenschaften, Institut für Forstnutzung und Forsttechnik, Professur für Forstnutzung durchgeführt. Reinforcement of oil palm wood by using Bioresin to improve its physical, mechanical and machinery properties. Concerning the utilization of oil palm wood, which is available in large number throughout the year, especially when the mature plants has reached its economic life span (approx. 25 years). Normally, this mature plant should be replanting. According to the projection of oil palm plantation development in Indonesia, there are more than 16 million cubic meter of this bulky material starting 2010. This large amount of biomass, if no real effort, will become a serious problem. Unfortunately, the current replanting method (push-felled) sounds risky and in several companies follow by burning method, which is really not solve problem, but creating the other serious problem, such as air pollution. The oil palm wood characteristics as a monocotyledons species is naturally quite different compare to the common wood (dicotyledonous). Originally the oil palm tree has various densities along the trunk and its density decreased linearly with trunk height and towards the centre of the trunk. Green oil palm trunk is also very susceptible to fungal and insect attack due to the high sugar and starch content. Hence, the utilization of this material is not fully utilized yet and still poses a serious environmental problem. Yet, compared to the various intensive researches and the economically important of the oil palm, processing technology and diversification of palm oil based products mainly from CPO and PKO, the oil palm solid waste, particularly the oil palm wood, has received relatively little research attention. This might be due to lack or insufficient the scientific information and Know-How of this material and might be also due to the difficulties of using with the OPT. Although several investigations have already conducted in the field of OPT, but a sufficient knowledge shall be achieved in order to design and establish the new tailor-made wood products based on oil palm wood. Hence, this study was directed to focus the characteristics of OPT including anatomical, physical, mechanical and machinery properties, and in order to use the OPT for structural purposes, the wood properties of OPT were improved and reinforced with Bioresin through the development of wood modification techniques.
Das Projekt "D 1.3: Regulation of flowering in tropical fruit crops on erosion prone sites in Northern Thailand" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Kulturpflanzenwissenschaften, Fachgebiet Ertragsphysiologie der Sonderkulturen (340f) durchgeführt. NRCT component: Assoc.Prof.Dr. Sruamsiri, Pittaya - Development of Clean Technology for Off-season Fruit Production: A Case Study of Mango, Longan, Litchi and Tangerine. Specific basic and applied science activities for each crop will be carried out in an attempt to solve the following issues. Longan: Previous research work has shown that flower induction can successfully be manipulated by application of KClO3. This crop is therefore an ideal model plant to investigate the regulatory mechanisms of flowering by: 1. determining acquisition and distribution of KClO3 using isotope labelling techniques and measuring enzyme activities in leaves to decide whether nitrate reductase is involved in the conversion and flower inducing activity of KClO3; 2. identifying mutual influences between hormones including their time-dependent changes brought about by manipulation of hormone biosynthesis through exogenously applied plant growth regulators (PGRs); 3. investigating the effect of off-season production systems on carbohydrate distribution and reserves. Mango: Paclobutrazol (PBZ) is already commercially used to manipulated flower induction in mango, however, the technique may not be sustainable due to its persistence in plant and soil. Prohexadione-Ca (Pro-Ca), another gibberellin biosynthesis inhibiting compound, and specific crop management techniques may prove to be successful and more sustainable alternatives to PBZ and warrant detailed investigation by: 1. evaluating appropriate time-of-season, concentration and application procedure (injection or spray) of Pro-Ca as possible alternative of PBZ and subsequent effects on hormonal status; 2. pruning or defoliation techniques which may induce a secondary flower through an altered hormonal status in the bud tissue. Litchi: There are still no proven orchard management practices for inducing off-season flowering in litchi. The main research objective is to study the significance of plant stress (pruning, girdling shoot tipping techniques, water and nutrient deficiency) on flowering signals by determining carbohydrate changes and hormonal status.
Das Projekt "Storage of hydrogen in hydrides" wird vom Umweltbundesamt gefördert und von Weierstraß-Institut für Angewandte Analysis und Stochastik durchgeführt. Hydrogen is the ideal synthetic fuel to convert chemical energy into electrical energy or into motive power because it is light weight, highly abundant and its oxidation product is vapor of water. Thus its usage helps to reduce the greenhouse gases and it conserves fossile resources. There is even a clean way to produce hydrogen by electrolysis of water by means of photo voltaics (SvW06, VSM05, PMM05). There are various possibilities to store the hydrogen for later use: Liquid and gaseous hydrogen can be stored in a pressure vessel, hydrogen can be adsorped on large surface areas of solids, and finally crystal lattices of metals or other compounds can be used as the storage system, where hydrogen is dissolved either on interstitial or on regular lattice sites by substitution (SvW06, San99). The latter process and its reversal is called hydriding respectively dehydriding. The subject of this proposal is the modeling and simulation of that process. The main problem of a rechargeable lithium-ion battery is likewise a storage problem, because in a rechargeable battery, both the anode and cathode do not directly take part in the electrochemical process that converts chemical energy into electrical energy, rather they act as host systems for the electron spending element, which is here lithium (Li). During the last month the applicant developed and exploited a mathematical model that is capable to capture the storage problem of an iron phosphate (FePO4) cathode, where the Li atoms are stored on interstitial lattice sites (DGJ07).
Das Projekt "Origin and fate of dissolved organic matter in the subsoil" wird vom Umweltbundesamt gefördert und von Leibniz Universität Hannover, Institut für Bodenkunde durchgeführt. Dissolved organic matter (DOM) is one major source of subsoil organic matter (OM). P5 aims at quantifying the impact of DOM input, transport, and transformation to the OC storage in the subsoil environment. The central hypotheses of this proposal are that in matric soil the increasing 14C age of organic carbon (OC) with soil depth is due to a cascade effect, thus, leading to old OC in young subsoil, whereas within preferential flowpaths sorptive stabilization is weak, and young and bioa-vailable DOM is translocated to the subsoil at high quantities. These hypotheses will be tested by a combination of DOC flux measurements with the comparative analysis of the composition and the turnover of DOM and mineral-associated OM. The work programme utilizes a DOM monitoring at the Grinderwald subsoil observatory, supplemented by defined experiments under field and labora-tory conditions, and laboratory DOM leaching experiments on soils of regional variability. A central aspect of the experiments is the link of a 13C-leaf litter labelling experiment to the 14C age of DOM and OM. With that P5 contributes to the grand goal of the research unit and addresses the general hypotheses that subsoil OM largely consists of displaced and old OM from overlying horizons, the sorption capacity of DOM and the pool size of mineral-associated OM are controlled by interaction with minerals, and that preferential flowpaths represent 'hot spots' of high substrate availability.
Das Projekt "Work Package II - Material processing at Haean Basin scale: The role of hyporheic exchange and the riparian zone in NO3 and DOC export from catchments" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Fachgruppe Geowissenschaften, Bayreuther Zentrum für Ökologie und Umweltforschung (BayCEER), Lehrstuhl für Hydrologie durchgeführt. The hydrogeochemical dynamics in mountainous areas of the Korean Peninsula are mainly driven by a monsoon-type climate. To examine the interplay between hydrological processes and the mobilization and subsequent transport and export of nitrate and DOC from catchments, a field study was initiated in the Haean catchment in north-eastern South Korea under highly variable hydrologic conditions. In order to identify nitrate and DOC source areas, a subcatchment (blue dragon river) within the Haean basin, which includes different types of landuses (forest, dry land farming, and rice paddies), was selected. In 2009, high frequency surface water samples were collected at several locations during summer storm events. A similar but more comprehensive sampling routine was completed in 2010. In order to investigate the groundwater level fluctuations relative to the hydraulic potentials, a piezometer transect was installed across a second order stream of the subcatchment. The results so far suggest deep groundwater seepage to the aquifer with practically no base flow contributions to the stream in the mid-elevation range of the catchment. In 2009 the focus of research was within the subcatchment, in 2010 additionally a second piezometer transect was installed at a third order stream in the lower part of the catchment (main stem of the Mandae River) where more dynamic groundwater/surface water interactions are assumed due to expected higher groundwater levels in this part of the basin. In order to investigate these interactions piezometers equipped with temperature sensors and pressure transducers were installed directly into the river bed. Based on the observed temperature time series and the hydraulic potentials the water fluxes between the groundwater and the river can be calculated using the finite-difference numerical code, VS2DH. VS2DH solves Richard s equation for variably-saturated water flow, and the advection-conduction equation for energy transport. The field data collected at the second piezometer transect suggest that the investigated river reach exhibits primarily losing surface conditions throughout most of the year. Gaining groundwater conditions at the river reach are evident after monsoonal extreme precipitation events. At the transect streambed aggradation and degradation due to bedload transport was observed. Significant erosion has been reported throughout the catchment after extreme events. Results indicate that the event-based changes in streambed elevation, is an additional control on groundwater and surface water exchange. The streambed flux reversals were found to occur in conjunction with cooler in-stream temperatures at potential GW discharge locations. The export of nitrate and DOC were found to be variable in time and strongly correlated to the hydrologic dynamics, i.e. the monsoon and pre- and post-monsoon hydrological conditions. usw.
Das Projekt "Establishment and exploration of a gas ion source for micro-scale radiocarbon dating of glaciers and groundwater" wird vom Umweltbundesamt gefördert und von Universität Heidelberg, Institut für Umweltphysik durchgeführt. Recent progress in the operation of CO2 gas ion sources for accelerator mass spectrometer (AMS) 14C analysis on microgram-size samples opens a wide range of new applications in dating studies, e.g. for environmental and archeological applications. This proposal aims at implementing a gas ion source at the AMS system MICADAS at the Klaus-Tschira Laboratory of the Curt-Engelhorn-Zentrum für Archäometrie (CEZA) in Mannheim and to use this new capability for cutting-edge applications in environmental studies, namely the dating of small amounts of organic carbon contained in glacier ice and of specific organic compounds in ground water. Cold glaciers hold unique records on past climate and atmospheric composition. Mid-latitude ice cores furthermore enable reconstructions of recent ice chemistry changes, but cannot be dated by stratigraphic methods. For such ice bodies, only radiometric dating based on 14C analysis of organic matter contained in the ice matrix presently offers a reasonable dating potential in the late Holocene and beyond. The challenge of this approach lies in the very restricted availability of this matter, but the ability to analyse microgram samples of organic carbon from ice via a gas ion source should now enable reliable 14C dating of ice. Ground water constitutes an important water resource worldwide, especially in semi-arid regions, and in addition constitutes a useful climate archive. Dating of ground water by 14C in the dissolved inorganic carbon (DIC) is standard but problematic due to the complex carbonate geochemistry. Dating of ground water based on dissolved organic carbon (DOC) has been attempted with mixed success, but now the new analytical developments enable compound-specific 14C analyses of the various DOC components, offering the chance to identify compounds suitable for dating. This project is based on the extensive experience of the collaborating scientists in 14C analytics and applications as well as in the use of glacier ice and ground water as archives, including the development and application of 14C dating methods for these systems. It will establish 14C-measurements at the MICADAS AMS of the CEZA via a gas ion source on a routine base to analyse CO2-samples in the range of 5 to 40 microgram C at a precision down to 0,5 Prozent. By improving existing sample preparation techniques for glacier ice samples, reliable 14C values of the particulate and dissolved organic fractions from small (some 100 g) ice samples shall be obtained. This capability will be applied to constrain ages of cold, sedimentary glaciers as well as of small scale, cold Alpine congelation ice bodies. The project will further develop and test the tools required for micro-scale, compound-specific radiocarbon dating of ground water via its organic fraction. For this purpose, ground water samples from the Upper Rhine Graben area will be analysed, where extensive isotopic data, including DIC 14C values, are available for comparison.
Das Projekt "The Water, Energy and Food Security Nexus" wird vom Umweltbundesamt gefördert und von Fachhochschule Köln, Institut für Technologie- und Ressourcenmanagement in den Tropen und Subtropen (ITT) durchgeführt. In order to understand the interlinked problems in the Nexus (Latin = connection, linkage, interrelation) of water, energy and food security, close cooperation between scientists and practitioners from different fields is necessary. The present and future challenge of a reliable supply with water, energy and food is an example, where isolated considerations do not lead to viable solutions. Sustainable action and meaningful research in these highly interconnected fields require a holistic and comprehensive perspective and a new approach. In this sense, a collaborative research structure with a holistic view on the Nexus of Water, Energy and Food security was established in 2013 at the Cologne University of Applied Sciences. The project bundles some of the research efforts of 11 professors from different faculties and institutes. The researchers jointly work on initiating new cooperation projects with partners from industry, academia and civil society. Together they aim at exploring new technologies and applying new approaches to solve major issues of efficiency and sustainability in resource use.
Das Projekt "Culture experiments on the gamma 13C values recorded in tests of benthic foraminifera from methane sources at high latitudes" wird vom Umweltbundesamt gefördert und von Stiftung Alfred-Wegener-Institut für Polar- und Meeresforschung e.V. in der Helmholtz-Gemeinschaft (AWI) durchgeführt. Since methane is a powerful greenhouse gas, significant releases of methane from instable submarine CH4 clathrates into the atmosphere have been hypothesized as a cause of past and possibly future climate changes (IPCC, 2007). The carbon isotope signature of benthic foraminifers, especially that of Fontbotia wuellerstorfi, has been considered a proxy to detect such clathrate dissociation induced climate changes. However, it has never been experimentally verified to what extent the foraminiferal ä13C signature reflects the release of methane. This is the goal of this project. The necessary experimental preconditions were successfully achieved during the current grant: (1) We established a unique 'high-pressure deep-sea cultivation laboratory' that allows culturing living benthic foraminifers in their original surrounding environment under in-situ (high-pressure) conditions using a newly developed autoclave system. (2) For the first time, this enabled both methane-related high-pressure cultivation experiments and successful reproduction of barophilic F. wuellerstorfi, one of the most important signal-carrier in palaeoceanography. Our future experiments are designed to (1) improve our understanding about the process of ä13C signal transfer from the methane source into the foraminiferal shell; (2) document to what extent the foraminiferal ä13C reflects the biological conversion from the CH4 source into the bottom water, which is measured by the ä13C of the dissolved inorganic carbon; and (3) examine the importance of the food source on the ä13C shell signature.
Das Projekt "Effekte von Nickel auf eine aquatische Lebensgemeinschaft in Mikrokosmen" wird vom Umweltbundesamt gefördert und von Fraunhofer-Institut für Molekularbiologie und Angewandte Oekologie durchgeführt. Quality standards to assess the chemical status of water bodies under the Water Framework Directive are often based on a few standardized laboratory tests and fixed assessment factors for extrapolation to the field situation. If larger data sets including tests with non-standard species are available, a statistical extrapolation approach, the Species Sensitivity Distribution approach (SSD) is applied. For assessing the remaining uncertainty on the SSD, the threshold concentration derived can be compared with data from field monitoring or model ecosystem studies. Taking the priority substance Ni as an example we present the use of microcosms to test the protectiveness of the quality standard derived from laboratory toxicity tests. The study was conducted in 14 microcosms including a natural sediment layer and an overlaying water volume of 750 L located in a greenhouse. After a pre-treatment period for establishing a diverse aquatic community of phytoplankton, zooplankton, periphyton and snails, Ni solution was added to reach concentrations of 6, 12, 24, 48 and 96 micro g Ni/L in two microcosms each. Four microcosms served as untreated controls. To achieve the intended constant exposure over the test period of four months, Ni concentrations were frequently determined in the microcosms and appropriate amounts of nickel solution were added mostly on a daily basis. Parameters known to affect Ni toxicity, i.e. water hardness, pH, and dissolved organic carbon, were also measured. Population abundance and community structure were analysed for difference to the dynamics in the controls. In the microcosms with 48 and 96 micro g Ni/L long-term effects on phytoplankton, rotifers, snails and, due to reduced grazing by snails, indirectly on the periphyton biomass were observed. Only minor, and/or temporary deviations from controls, i.e., for single sampling dates, were found for a few algae taxa at lower concentrations. Because these deviations showed no clear dose-response and were not found at the end of the study they were not seen as adverse effects. However, for the snail (Lymnaea stagnalis), effects on the trend of population development could not be excluded at 24 micro g/L. Thus, the overall No Observed Effect Concentration (NOEC) for a chronic exposure to nickel in this microcosm study was considered to be 12 micro g Ni/L. This NOEC confirms the protectiveness of the quality standard derived from the laboratory single species tests.
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