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B 2.3: Transport of agrochemicals in a watershed in Northern Thailand - Phase 3

Das Projekt "B 2.3: Transport of agrochemicals in a watershed in Northern Thailand - Phase 3" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre, Fachgebiet Biogeophysik durchgeführt. Land use changes of the last decades in the mountainous regions of Northern Thailand have been accompanied by an increased input of agrochemicals, which might be transferred to rivers by surface and/or subsurface flow. Where the river water is used for household consumption, irrigation and other purposes, agrochemical losses pose a serious risk to the environment and food safety. In the first and the second phase, subproject B2 collected data on and gained knowledge of the vertical and lateral transport processes that govern the environmental fate of selected agrochemicals at the plot and the hillslope scale (Ciglasch et al., 2005; Kahl et al., 2006). In the third phase, B2.3 will turn from the hillslope to the watershed scale. For simulation of water flow and pesticide transport the SWAT model (Neitsch et al., 2002b) will be adapted and used. The study area will be the Mae Sa watershed (138 km2), which includes the Mae Sa Noi subcatchment where B2 carried out detailed investigations during the last two phases. The specific focus of the subproject will be the parameterization and calibration of the SWAT model and its integration into the model network of the SFB. The SFB database has been established and can be used for model parameterization. In addition, high-quality geo-data are available from the Geoinformatic and Space Technology Development Agency (GISTDA) in Chiang Mai. For model calibration, discharge measurements are available for the Mae Sa Noi subcatchment (12 km2) and for the neighboring Mae Nai subcatchment (18 km2). To collect data on the Mae Sa watershed discharge, at the very beginning of the third phase gauging stations will be established in a midstream position and at the outlet of the watershed. Pesticide fluxes will be measured at each gauging station as well as in the Mae Sa Noi subcatchment, where B2.2 has operated two flumes equipped with automatic discharge-proportional water samplers since 2004. Rainfall distribution and intensity will be monitored with a net of automatic rain gauges. Hydrograph separation will be performed using soil and river temperatures (Kobayashi et al., 1999). Within the watershed temperature loggers will be installed at different soil depths to measure the temperature of the different discharge components. Already at the beginning of the second year of the third phase we will start to couple the SWAT model with land use and farm household models of the SFB and to use the model to assess the effect of land use and land management changes on the loss of pesticides to surface waters.

B 5.1: Fate of agrochemicals in integrated farming systems in Son-La province, Northern Vietnam

Das Projekt "B 5.1: Fate of agrochemicals in integrated farming systems in Son-La province, Northern Vietnam" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre, Fachgebiet Biogeophysik durchgeführt. In Son La province, Northern Vietnam, many irrigated farming systems include ponds in which small-scale farmers raise fish to produce additional food and income. The main field crops in this area are paddy rice and maize. Often, irrigation water is first used in paddy fields, before it flows to the fishponds. Because farmers regularly apply considerable amounts of agrochemicals, mainly insecticides, to field crops fish production suffers. Moreover, agrochemicals may enter the human food chain. Subproject B5.1 will study the fate of agrochemicals applied in two subcatchments near Yen Chau, Son La province. Investigations will be carried out in close collaboration with A1.3, B4.1, C4.1, D5.2, and G1.2. In the two subcatchments, fishponds have been investigated by D5.1 since 2003. We will carry out a survey of the subcatchments with special emphasis on the water distribution systems (fields, ponds, canals, brooks). The data will be linked to the GIS (Geographical Information System) set up by B4.1. In one subcatchment, B5.1 will install a weather station as well as five TDR (time do-main reflectometry) probes and tensiometers. Water flow through the system will be recorded by means of water meters and V-shaped (Thompson) weirs equipped with automatic pressure sensors. Soil and water samples from selected fields sites, pond inflows, and ponds will be regularly screened for agrochemicals using the procedure developed by B2.1 (Ciglasch et al., 2005; see below). Soil and sediment characteristics that determine water regime and soil-agrochemical interaction, e.g. texture, organic carbon content, hydraulic conductivity, partitioning coefficients, and half-life times will be measured in laboratory and field experiments in cooperation with B4.1. In preparation for the next phase, discharge will be assessed and agrochemical concentrations monitored in the main catchment.

WiSSCy: Impact of Wind, Rain, and Surface Slicks on Air-Sea CO2 Transfer Velocity - Tank Experiments

Das Projekt "WiSSCy: Impact of Wind, Rain, and Surface Slicks on Air-Sea CO2 Transfer Velocity - Tank Experiments" wird vom Umweltbundesamt gefördert und von Universität Hamburg, Zentrum für Meeres- und Klimaforschung, Institut für Meereskunde (IfM) durchgeführt. The goal is to improve the understanding of the parameterization of air-sea gas exchange with emphasis on CO2. This is being done using the linear wind-wave tank facility of the University of Hamburg. Using this facility, gas exchange coefficients are inferred by measuring gas transfer under a wide variety of parameters such as wind, mechanically generated waves, rain, and surface films. Our emphasis is on the physical processes involved in the air-sea gas exchange and its quantitative measurement. Experiments are conducted with freshwater and with salt water to test the influence of salinity on the gas exchange parameters. All experiments are being performed for evasion and invasion to investigate if rain-induced gas transfer is symmetrical or asymmetrical. While these experiments do not address in great detail the small-scale processes that are involved in the transfer, they allow to determine parameterizations of the gas exchange as a function of parameters of the atmospheric boundary layers as they are needed in climate models and for the analysis of satellite data.

The role of turgor in rain-cracking of sweet cherry fruit

Das Projekt "The role of turgor in rain-cracking of sweet cherry fruit" wird vom Umweltbundesamt gefördert und von Leibniz Universität Hannover, Institut für Biologische Produktionssysteme, Fachgebiet Obstbau durchgeführt. Rain-cracking limits the production of many soft and fleshy fruit including sweet cherries world wide. Cracking is thought to result from increased water uptake through surface and pedicel. Water uptake increases fruit volume, and hence, turgor of cells (Pcell) and the pressure inside the fruit (Pfruit) and subjects the skin to tangential stress and hence, strain. When the strain exceeds the limits of extensibility the fruit cracks. This hypothesis is referred to as the Pfruit driven strain cracking. Based on this hypothesis cracking is related to two independent groups of factors: (1) water transport characteristics and (2) the intrinsic cracking susceptibility of the fruit defined as the amount of cracking per unit water uptake. The intrinsic cracking susceptibility thus reflects the mechanical constitution of the fruit. Most studies focussed on water transport through the fruit surface (factors 1), but only little information is available on the mechanical constitution (i.e., Pfruit and Pcell, tensile properties such as fracture strain, fracture pressure and modulus of elasticity of the exocarp; factors 2). The few published estimates of Pfruit in sweet cherry are all obtained indirectly (calculated from fruit water potential and osmotic potentials of juice extracts) and unrealistically high. They exceed those measured by pressure probe techniques in mature grape berry by several orders of magnitude. The objective of the proposed project is to test the hypothesis of the Pfruit driven strain cracking. Initially we will focus on establishing systems of widely differing intrinsic cracking susceptibility by varying species (sweet and sour cherry, Ribes and Vaccinium berries, plum, tomato), genotype (within sweet cherry), stage of development and temperature. These systems will then be used for testing the hypothesis of Pfruit driven strain cracking. We will quantify Pfruit und Pcell by pressure probe techniques and compression tests and the mechanical properties of the exocarp using biaxial tensile tests. When the presence of high Pfruit and Pcell is confirmed by direct measurements, subsequent studies will focus on the mode of failure of the exocarp (fracture along vs. across cell walls) and the relationship between failure thresholds and morphometric characteristics of the exocarp. However, when Pfruit und Pcell are low, the hypothesis of Pfruit driven strain cracking must be rejected and the mechanistic basis for low pressures (presence of apoplastic solutes) clarified on a temporal (in the course of development) and a spatial scale (exocarp vs. mesocarp). We focus on sweet cherry, because detailed information on this species and experience in extending the short harvest period is available. Where appropriate, other cracking susceptible species (sour cherry, plum, Vaccinium, Ribes, tomato) will be included to further extend the experimental period and to maximize the range in intrinsic cracking susceptibility.

Towards a Guideline for Digital Soil Mapping in Ecuador

Das Projekt "Towards a Guideline for Digital Soil Mapping in Ecuador" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Abteilung Bodenphysik durchgeführt. Research experience in digital soil mapping (DSM) shall be extended and deepened in two further research areas in order to develop a guideline for DSM in Ecuador. The guideline will give an overview: a) about the DSM approach, b) the different sampling designs developed according to the area size, accessibility and terrain complexity, c) the various methods from the field of supervised machine learning to develop digital soil maps, and d) the implementation with open source software. The soil-landscapes of the three investigation areas will be analysed and soil-landscape models will be developed by supervised machine learning techniques, in order to spatially predict soil properties from point data based on environmental prediction parameters. By using the so developed digital soil maps as principal input, a functional soil-landscape analysis is carried out to determine landslide, erosion and anthropogenic disturbance risk zones as well as estimate the soil organic carbon stocks and soil fertility.

B 1.2: Efficient water use in limestone areas - Phase 2

Das Projekt "B 1.2: Efficient water use in limestone areas - Phase 2" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre durchgeführt. The elevated areas of Northern Thailand highlands are inhabited by ethnic minorities. On the other hand, the Thai majority prefers the valley bottoms. Population growth of all groups, reforestation and commercialisation of agriculture lead to an increasing pressure on land and water resources. Therefore, intensified land and water use systems are desired which are resource conserving at the same time. Here, special problem areas are the karstic limestone catchments due to the limited of surface waters.Own pre-investigations together with subproject A1 have shown, that land use systems there are subsistence oriented and local farmers do not use irrigation. But they would like to develop such technology, especially in order to increase staple crop production (highland rice, maize). But lack of irrigation possibilities is also responsible for the lack of diversification of land use systems with respect to orchards. One possibility to increase staple crop yields is to prolong the vegetation period by use of water harvesting technologies. Aim of this project is to develop such low cost water harvesting technologies (together with subproject B3.1) based on a participatory approach and to model the effect of these on the water balance at the catchments scale. This will be done on the basis of the previous variability studies and should lead to model tools, which allow to evaluate ex ante SFB innovation effects on the water balance. The project area is the Bor Krai catchments. Here, weirs will be installed to quantify surface water availability. An investigation plot will be situated near the village of Bor Krai which serves for water balance measurements (TDR/densitometry) and at the same time as demonstration plot for the local community. Here water harvesting by means of filling the soils field capacity at the end of the rainy season by gravity irrigation in order to prolong the vegetation period will be researched. Through cropping of participatory evaluated varieties the crop yield should be increased. The water consumption of traditionally managed and dominant crops (including orchards) will be measured at three further sites in the catchment (TDR, tensiometer). The water balance of the soil cover in the karst catchment will be based on the coupling of a SOTER map with a water transport model. The data base will be completed by soil type mapping, spatially randomised collection of soil physical properties (texture, bulk density, infiltration, water retention curve) and determination of the ku-function at two representative sites. As project results the available water amount for irrigation purposes will be quantified. The effective use of this water reserve will lead to increased productivity of the dominant crops and limitations to orchard productivity will be reduced. (abridged text)

C-STAR: Coastal Sediment Transport Assessment Using SAR Imagery

Das Projekt "C-STAR: Coastal Sediment Transport Assessment Using SAR Imagery" wird vom Umweltbundesamt gefördert und von Universität Hamburg, Zentrum für Meeres- und Klimaforschung, Institut für Meereskunde (IfM) durchgeführt. C-STAR was a joint European project, carried out by ten partner institutions in the Netherlands, Belgium, Great Britain, and Germany; financially supported by the Commission of the European Community as a part of the Marine Science and Technology (MAST) program under contract no. MAS3-CT95-0035.. C-STAR was devoted to an improved theoretical understanding of the radar imaging of underwater bottom topography in tidal waters and to an investigation of the potential of inverse models which retrieve topographic maps from radar images, for morphological research and monitoring applications. C-STAR included a major field experiment off the Dutch coast, which was carried out in April, 1996. The activities of the Satellite Oceanography group of the University of Hamburg within C-STAR focused on the improvement of theoretical models for the hydrodynamic wave-current interaction and for the radar backscattering at the sea surface, which appears to be described relatively well by the existing composite surface model.

High density power electronics for FC- and ICE-Hybrid Electric Vehicle Powertrains (HOPE)

Das Projekt "High density power electronics for FC- and ICE-Hybrid Electric Vehicle Powertrains (HOPE)" wird vom Umweltbundesamt gefördert und von Siemens AG durchgeführt. Objective: The project HOPE is addressing power electronics. It is based on previous EU research projects like the recently finished FW5 HIMRATE (high-temperature power modules), FW5 PROCURE (high-temperature passive components), and MEDEA+ HOTCAR (high-temperature control electronics) and other EU and national research projects. The general objectives of HOPE are: Cost reduction; meet reliability requirements; reduction of volume and weight. This is a necessity to bring the FC- and ICE-hybrid vehicles to success. WP1 defines specifications common to OEM for FC- and ICE-hybrid vehicle drive systems; Identification of common key parameters (power, voltage, size) that allows consequent standardisation; developing a scalability matrix for power electronic building blocks PEBBs. The power ranges will be much higher than those of e.g. HIMRATE and will go beyond 100 kW electric power. WP2 works out one reference mission profile, which will be taken as the basis for the very extensive reliability tests planned. WP3 is investigating key technologies for PEBBs in every respect: materials, components (active Si- and SiC switches, passive devices, sensors), new solders and alternative joinings, cooling, and EMI shielding. In WP4 three PEBBs will be developed: HDPM (high density power module) which is based on double side liquid cooling of the power semiconductor devices; IML (power mechatronics module), which is based on a lead-frame technology; and SiC-PEBB inverter (silicon carbide semiconductor JFET devices instead of Si devices). WP5 develops a control unit for high-temperature control electronics for the SiC-PEBBs. Finally WP6 works on integrating the new technologies invented in HOPE into powertrain systems and carries out a benchmark tests. All the results achieved in HOPE will be discussed intensively with the proposed Integrated Project HYSIS where the integration work will take place. It is clear from the start that many innovations are necessary to meet the overall goal.

Soil N dynamics as affected by different land use in Western and Southern China

Das Projekt "Soil N dynamics as affected by different land use in Western and Southern China" wird vom Umweltbundesamt gefördert und von Technische Universität Dresden, Institut für Bodenkunde und Standortslehre durchgeführt. The aim of the research project is to quantify the stocks and turnover of soil nitrogen in Western and Southern China as dependent from soil structure and land use. Key soil characteristics are determined at representative sites with regional specific land use and degradation status. The investigations will follow a land use gradient of natural forests, arable and pasture soils, the latter ones considering different degradation and rehabilitation status. The actual and potential soil nitrogen turnover will be horizon-wise quantified and related to soil structure and land use impacts. Beside mineral nitrogen, also preliminary organic N compounds using physical and chemical extraction will be detected. Parameters for the investigations are, beside total C and N stocks and distribution, gross and net N mineralization, nitrification, microbial biomass C and N and microbial respiration and indicators for soil N turnover like active N pools and light fraction of organic matter. In the last phase the structure of the soil microbial microbial community will be determined and related to indicators of nitrogen status and efficiency. The research activities will be carried out in close co-operation with the Institute for Soil and Water Conservation/ Yangling University at loess soils and the Nanjing Institute for Soil Science/ Chinese Academy for Science in Nanjing at red soil sites.

Palaeo-Evo-Devo of Malacostraca - a key to the evolutionary history of 'higher' crustaceans

Das Projekt "Palaeo-Evo-Devo of Malacostraca - a key to the evolutionary history of 'higher' crustaceans" wird vom Umweltbundesamt gefördert und von Universität Greifswald, Zoologisches Institut und Museum, Abteilung Cytologie und Evolutionsbiologie durchgeführt. In my project I aim at a better understanding of the evolution of malacostracan crustaceans, which includes very different groups such as mantis shrimps, krill and lobsters. Previous studies on Malacostraca, on extant as well as on fossil representatives, focussed on adult morphology.In contrast to such approaches, I will apply a Palaeo-Evo-Devo approach to shed new light on the evolution of Malacostraca. Palaeo-Evo-Devo uses data of different developmental stages of fossil malacostracan crustaceans, such as larval and juvenile stages. With this approach I aim at bridging morphological gaps between the different diverse lineages of modern malacostracans by providing new insights into the character evolution in these lineages.An extensive number of larval and juvenile malacostracans is present in the fossil record, but which have only scarcely been studied. The backbone of this project will be on malacostracans from the Solnhofen Lithographic Limestones (ca. 150 million years old), which are especially well preserved and exhibit minute details. During previous studies, I developed new documentation methods for tiny fossils from these deposits, e.g., fluorescence composite microscopy, and also discovered the first fossil mantis shrimp larvae. For malcostracan groups that do not occur in Solnhofen, I will investigate fossils from other lagerstätten, e.g., Mazon Creek and Bear Gulch (USA), or Montceaules- Mines and La-Voulte-sur-Rhône (France). The main groups in focus are mantis shrimps and certain other shrimps (e.g., mysids, caridoids), as well as the bottom-living ten-footed crustaceans (reptantians). Examples for studied structures are leg details, including the feeding apparatus, but also eyes. The results will contribute to the reconstruction of 3D computer models.The data collected in this project will be used for evaluating the relationships within Malacostraca, but mainly for providing plausible evolutionary scenarios, how the modern malacostracan diversity evolved. With the Palaeo-Evo-Devo approach, I am also able to detect shifts in developmental timing, called heterochrony, which is interpreted as one of the major driving forces of evolution. Finally, the reconstructed evolutionary patterns can be compared between the different lineages for convergencies. These comparisons might help to explain the convergent adaptation to similar ecological niches in different malacostracan groups, e.g., life in the deep sea, life on the sea bottom, evolution of metamorphosis or of predatory larvae.As the project requires the investigation of a large number of specimens in different groups, I will assign distinct sub-projects to three doctoral researchers. The results of this project will not only be published in peer-reviewed journals, but will also be presented to the non-scientific public, e.g., during fossil fairs or museum exhibitions with 3D models engraved in glass blocks.

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