Swiss Lakes

The majority of published data in fish samples expressed PBDE levels in ng/g lipid weight (lw), making difficult the comparison with our results expressed in ng/g ww. However, some works also used the same unities of this study. Zennegg et al. [34] analyzed whitefish from different Swiss lakes, and reported PBDE levels between 1.6 and 7.4 ng/g ww. Carps from Detroit river and Des Plaines river [35] presented PBDE concentration levels around 5 ng/g ww and 12 ng/g ww, respectively. All these values were in accordance with our results in sites out of industrial impact (sites Cl and C2). 

Buser, H.-R., Muller, M. D. and Theobald, N. (1998). Occurrence of the pharmaceutical drug clofibric acid and the herbicide mecoprop in various Swiss lakes and in the North Sea, Environ. Sci. Technol., 32, 188-192. 

Cadmium in the Greifensee Lake (Stumm and Morgan, 1981). This Swiss lake has a volume V of 1.25 x 108 m3, water input is (2 = 9 x 107 m3 a"1, sedimentation rate is P=4x 107kga 1. Cd has a sediment-water partition coefficient DCd = 65m3kg1. Calculate the Cd residence time in the lake. 

The distribution of LAS in continental sediments has been studied [55], and the vertical profiles of LAS concentrations with depth in several lake sediments have been established [56,57]. In Swiss lakes, the concentration of LAS increases with depth and this is due to the efficiency of the wastewater treatment plants. Amano et al. [56] have, however, observed a decrease in the concentration of LAS with depth, and detected seasonal variations in the profile of LAS in the uppermost surface layer. 

Experimental evidence obtained from Swiss lakes were compared with model simulations so as to evaluate effects that coagulation can have in lakes. In the course of this study special attention was directed towards the chemical factors that influence colloidal stability in natural waters. 

Poiger, T. Buser, H.-R. Balmer, M.E. Bergqvist, P.-A. Muller, M.D. 2004, Occurrence of UV filter compounds from sunscreens in surface waters Regional mass balance in two Swiss lakes. Chemosphere 55 951—963. 

One of the next big realizations came with the publication of a paper by Buser [4]. These researchers had been analyzing samples from Swiss lakes and the North... 

Figure 15.11 Decadic beam attenuation coefficients calculated per milligram of DOC as a function of wavelength for a series of water samples from various Swiss lakes and rivers (data from Haag and Hoigne, 1986).

In Table 15.6, a(24 h) is calculated for PNAP for the well-mixed epilimnion of a small eutrophic lake (our example is Greifensee in Switzerland zmjx = 5 m, [DOC] = 4 mg C-L 1 a(A) values are given in Table 15.6) on a clear midsummer day at 47.5°N latitude. The result is a(24 h) = 22.5 einstein (mol PNAP)-1 day1. This absorption rate implies that each PNAP molecule is excited only about once an hour in this opaque water case, much less than once a minute in the transparent extreme (see above). Before we can be sure that our assumption that mixing (typical vertical mixing rates in the epilimnion of Swiss lakes are, for example, between 1 and 10 day-1) is fast as compared to the photolytic transformation of PNAP in the epilimnion of this lake is correct, we must discuss quantum yields. 

Ulrich et al. (1994) reported that the kbio values necessary to explain the mass balance of nitrilotriacetic acid (NTA) present in a Swiss lake at 1 to 10 nM ranged from 0.02 to 0.05 d 1. In another study, Bartholomew et al. (1983) tested an estuarine water for NTA biodegradation as a function NTA concentration, and they found Vmsx between 0.3 and 3 nmol-L-1 h 1 and KiMM between 300 and 600 nM. Are the results of these two investigations consistent Identify any assumptions you must make. 

Figure 22.7 Vertical turbulent diffu-sivity Ez versus square of stability frequency V2 in two Swiss lakes (see Eq. 22-32). (a) For Umersee (maximum depth 196 m), a basin of Lake Lucerne, the data refer to 10-100 m depth and indicate shear-produced turbulence. (b) For Zugersee (maximum depth 198 m) the values are calculated for an extreme storm of about two days duration. The data refer to the depth interval between 10 and 70 m they show a mixture between turbulence production by local shear and large-scale motion. (Fromlmboden and Wuest., 1995.)...

Peeters et al. (1996) have made a series of experiments with artificial tracers added to the upper hypolimnion of several Swiss lakes or basins of lakes (basin size between 5 and 220 km2). They always found elongated cloud shapes which they approximated by ellipses. The principal axes grew with time as ... 

The meaning and typical sizes of the coefficients Ax and A2 are discussed in Box 22.4. From Eq. 22-44 we note that for small times t, c2(t) grows as f, whereas for large times it grows as i2. The critical time, crit, defined in Eq. 3 of Box 22.4 separates the two regimes. Figure 22.10 shows a2(() curves from different experiments conducted in Swiss lakes. In Illustrative Example 22.3 the shear diffusion model is applied to the case of an accident in which a pollutant is added to the thermocline of a lake. 

Figure 8A. Rates of sulfur and carbon accumulation are highly correlated in surface sediments of 11 Swiss lakes (23). The solid line is the regression line and the dotted lines represent 95% confidence intervals. Variations in the carbon accumulation rates represent differences in trophic status and...

Total S content cannot indicate whether increased carbon inputs to sediments cause increased diffusion of sulfate into sediments or restrict reoxidation and release of S from sediments, because the net effect is the same. In a survey of 14 lakes, Rudd et al. (80) did not observe a strong correlation between organic matter content per volume and net diffusive flux of sulfate. However, in English lakes the lowest C S ratios occur in the most productive lakes (24) whether this represents enhanced influx or retarded release is not clear. Among 11 Swiss lakes, ratios of C to S sedimentation rates are relatively constant and substantially below C S ratios in seston net S fluxes... 

Emmenegger, L., D. W. King, L. Sigg, and B. Sulzberger. 1998. Oxidation kinetics of Fe(II) in a eutrophic Swiss lake. Environmental Science and Technology 32 2990-2996. 

Zennegg, M., Kohler, M., Gerecke, A.C., Schmid, P., 2002. Polybrominated diphenyl ethers in whitefish from Swiss Lakes and farmed rainbow trout. Chemosphere 51, 545-553. 

Czuczwa JM, Niessen F, Hites RA (1985), Chemosphere 14 1175-1179.. .Historical record of polychlorinated dibenzo-p-dioxins and dibenzofurans in Swiss lake sediments"... 

In addition, although most abiotic processes are nonenantioselective, not aU are indeed the case. Nucleophilic 5 jv2-substitution reactions at a chiral center will result in chiral inversion to the antipodal enantiomer. While such processes are often biologically mediated, as for the nonsteroidal anti-inflammatory drugs [328], they can also be abiotic. Appropriate sterile controls should be used for experiments with such compounds, as was done in the demonstration of microbial chiral inversion of ibuprofen in Swiss lake water [329]. Photolysis of a-HCH [114], /3-PCCH [114], and chlordane compounds [116] was demonstrated not to be enantioselective, as expected for an abiotic process. However, this may not be the case for some pyrethroids, known to isomerize photolytically. 

Balmer, M.E., Buser, H.R., Muller, M.D., Poiger, T. Occurrence of some organic UV filters in wastewater, in surface waters, and in fish from Swiss Lakes. Environ. Sci. Technol. 39, 953-962(2005)... 

P.J. Neale, E. Litchman, C. Sobrino, C. Callieri, G. Morabito, V. Montecino, Y. Huot, P. Bossard, D. Steiner, C. Lehmann (2001). Quantifying the response of phytoplankton photosynthesis to ultraviolet radiation Biological weighting functions versus in situ measurements in two Swiss lakes. Aquat. Sci., 63,265-285. 

Uehlinger, U., and J. Bloesch (1989), Primary Production of Different Phytoplankton Size Classes in an Oligo-mesotrophic Swiss Lake, Arch. Hydrobiol. 116, 1-21. 

Nutrients (Phosphorous, Nitrogen, Carbon-BOD) in Lacustrine Sediments" (Swiss Lakes Swedish Lakes Lakes in Wisconsin, Illinois and Michigan)... 

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