Description: Das Projekt "Sedimentation and erosion processes (WP EXPO 1)" wird vom Umweltbundesamt gefördert und von Universität Stuttgart, Institut für Wasserbau durchgeführt. All the data collected in BASIN 1 and SITE 1 on hydraulics and sediment, in particular at the hotspots must be evaluated to model the relationship between the flow field, erosion and sedimentation processes. Focusing on hotspots mobilized by erosive hydraulic conditions and their impact on the river ecosystem the critical flow parameters for the onset of erosion must be specified as well as the rate of contaminated sediment release (Witt, Westrich 2003). The sediment erosion mass flux plays an important role because it controls the source strength of pollutants and therefore, determines the concentration field not only of the resuspended particulate contaminants but also of the dissolved pollutants associated with the pore water. The erosion is the triggering mechanism followed up by the hydrodynamic transport, desorption and remobilization of sediment bound contaminants and, finally results in sedimentation of remaining polluted fractions downstream in headwaters and stagnant water bodies like groyne fields or harbors and flood plains. The combined effect of physical (grain size), chemical and biological (EPS) factors on the sediment erosion stability is not at all fully understood as to formulate the respective model terms (Haag, Westrich 2001). Therefore, a geostatistical evaluation of erosion relevant sediment parameters in terms of averaged values, spatial variance and uncertainty is required which allows to account for the probabilistic component of erosion and sedimentation processes and the resulting exposure (Li, Westrich 2001, Li 2004). Special interest will be given to the contaminated sediment depth profile which in combination with the duration of an erosive event and the rate of erosion controls the contaminant source strength. In addition, the hydraulic conditions at the hotspots will be derived from hydrological data for a rough erosion potential estimation. By multiple regression analysis of the hydraulic and sediment data a preliminary general parameterized description of erosion processes applicable to the three river basins (Elbe, Scheldt, Llobregat) can be delivered. This enables to describe different hydrological scenarios with variable flow field and site specific erosion related sediment parameters (Witt 2004). The modeling of sedimentation processes requires detailed information on suspended sediment parameters, in particular on the settling velocity of the contaminated fraction because of its model key function. Those parameters can only roughly be estimated from the existing data and hence, actual measurements in SITE 1 and particle size measurements must be performed (UfZ, Leipzig). Further gaps in the data set, e.g. partitioning coefficient Kd, will be identified and filled by the experiments in SITE 1. The model approach will be validated by targeted experiments performed in SITE 1. usw.
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Stuttgart ? Leipzig ? Hydrodynamik ? Messstation ? Schadstoffgehalt ? Biopharmazeutikum ? Wasserwirtschaftliche Daten ? Kombinationswirkung ? Rohwasser ? Schadstoffbelastung ? Sportanlage ? Stillgewässer ? Erosion ? Europäische Gemeinschaften ? Elbe ? Erosionsschutz ? Hydraulik ? Limnisches Ökosystem ? Partikelgrößenverteilung ? Porenwasser ? Regressionsanalyse ? Statistisches Modell ? Szenario ? Verfahrensparameter ? Hafen ? Flussaue ? Buhne ? Fließgewässerökosystem ? Schadstoffausbreitung ? Chemikalien ? Messverfahren ? Modellversuch ? Strömungsfeld ? Überschwemmungsgebiet ? Daten ? Wasserbau ? Wassergefährdende Stoffe ? Sediment ? In-Situ-Verfahren ? Flussgebiet ? Modellierung ? Korngröße ? Bewertung ? Messdaten ? Desorption ? Schadstoffmobilisierung ? Ökosystem ? Partikel ? Kenngröße ? Sedimenttransport ? Schadstoffakkumulation ? Mittelwert ? Schadstoffquelle ? Sedimentation ?
Region: Baden-Württemberg
Bounding boxes: 9° .. 9° x 48.5° .. 48.5°
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 2005-01-01 - 2009-03-30
Webseite zum Förderprojekt
http://www.modelkey.org/ (Webseite)Accessed 1 times.