Neckar River

Neckar River, FRG Max. 320 Pigment factory Fdrstner and Muller (1974)... 

Song, Y., Muller, G., 1995. Biogeochemical cycling of nutrients and trace metals in anoxic freshwater sediments of the Neckar river, Germany. Mar. Freshwater Res. 46, 237-243. 

It is assumed that the aquifer is confined and hydraulically homogeneous (average hydraulic transmissivity T= 10 m /s, gradient of the natural uniform flow field /= 0.2 %) and composed of Neckar river alluvial (NRA). The lithological composition and grain size distribution of NRA (Tab. 7.1), as determined by Riigner et al. (1997), is... 

Table 7.1 Lithological composition and grain size distribution of Neckar river alluvial (NRA).

KYPKE-HUTTER K, VOGELGESANG J, MALISCH R, BINNEMAN P and WETZLAR H The origin of contamination of fish from the River Neckar with hexachlorobenzene octachlorostyrene and pentachlorobenzene formation in an industrial process. 1. The course of the contamination in the upper section of the River Neckar , Z. Lehensm. Enters. Forsch., 1986 182 464-470. 

Figure 10.3. Size exclusion chromatogram obtained by UV and OC detection (SEC/UV-DOC) for a river sample (river Neckar, Heidelberg, 22.03.2007, DOC = 2.3 mg liter 1, chromatographable organic carbon (COC = 75%). Column TSK HW50S (250 x 20mm). Eluent phosphate buffer, 26.8mmol liter 1, UV (254nm) and organic carbon (OC) detection, exclusion volume V0, permeation volume Vp).

Hollert, H., Durr, M., Olsman, H., Halldin, K., van Bavel, B., Brack, W., Tysklind, M., Engwall, M. and Braunbeck, T. (2002a) Biological and chemical determination of dioxin-like compounds in sediments by means of a Sediment Triad approach in the catchment area of the River Neckar, Ecotoxicology 11, 323-336. 

Gerbersdorf, S., Jancke, T. and Westrich, B. (2005) Physico-chemical and biological sediment properties determining erosion resistance of contaminated riverine sediments temporal and vertical pattern at the Lauffen reservoir. River Neckar, Germany, Limnologica, 35, pp. 132-144. 

In situ data from the River Neckar were likewise juxtaposed to model data, assuming that the river can be represented initially as a one-dimensional system. Here again the concept of a critical settling velocity, determined by particle and flow system characteristics (leading to a transport capacity Ceq/Co), leads to a satisfactory reproduction of the observed data. 

Validity. To prove the applicability of the model, the first in situ measurements were performed in the Neckar, an impounded river, under almost stationary flow conditions. A tracer (Rhodamine B) was dosed into the eflluent of a sewage treatment plant. The outlet of the channel was situated at the right bank of the river with an angle of 35° between the river axis and the channel. The concentration proflles in a transverse direction were measured with a fluorometer installed on a boat. Preliminary measurements showed that the river is well-mixed along the depth, so that a sample taken at a depth of 1 m could be considered representative. The discharge of the river was 51 m /sec and the discharge of the treatment plant was 1.2 m /sec. 

Figure 5. Observed and computed concentration profiles (lateral) for an inert substance discharged into the River Neckar. Data are from an in situ investigation of a Rhodamine B plume in the Neckar. Rhodamine was...

Next, the distribution of particulates was measured in the same section of the River Neckar under conditions similar to those just described the concentration of the particulates at the discharge was ten times as high as in the river. Observed data were then compared to data computed with the model (that is, Equations 1-4, 6, and 12). Figure 6 shows the results of the computation. Part A (one-dimensional consideration) testifies to the reasonable agreement between observed and calculated data and Part B (two-dimensional consideration) exemplifies the type... 

Figure 6A. Observed and computed paniculate profiles in a sedimenting environment (River Neckar). Data stem from an in situ analysis of suspended particles in the River Neckar, downstream from a wastewater discharge with relatively high particle concentration. (- - -) aggregation only (- -) sedimentation only (-----) aggregation and sedimenta-...

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