Lakes water chemistry

It is roughly estimated that there are more than 1,200,000 water bodies in eastern North America that are currently affected by acid deposition. A subset of these lakes has been sampled since early 1980s in order to monitor the changes in lake water chemistry induced by the declining sulfur dioxide emissions and wet sulfate deposition... 

Mosello R, The MOLAR Water Chemistry Group et al (1999) The MOLAR project atmospheric deposition and lake water chemistry. J Limnol 58 88... 

Past lake-water chemistry changes can be determined by comparison of historical with current measurements hindcasts using empirical and dynamic computer models space-for-time substitutions (i.e., comparisons between the affected lakes and similar but unaffected lakes) and paleolimnological studies. Of these, paleolimnology is the only approach that does not require the existence of historical data or a thorough understanding of all important watershed and in-lake biogeochemical processes. 

The potential usefulness of the equation is indicated by the strength of the correlation between observed and inferred values characterized by the coefficient of determination (r2), as well as the standard error and the 95% confidence intervals associated with the regression. The overriding value of the relationship is that it can be used to infer past lake-water chemistry characteristics, with quantitative error estimates (e.g., The lake-water pH value, inferred from the sediment deposited at the 5.0-cm interval, is 6.3 with an estimated standard error of 0.3 pH units. ). To base inferred values only on the percent abundance of a limited number of categories is wasteful... 

Figure 6. Canonical correspondence analysis for surface sediments of 41 lakes in British Columbia, Canada, that encompass a broad range of trophic states. Circles represent lakes and triangles represent the 25 most abundant diatom taxa. Arrows indicate environmental variables that correlate most strongly with the distribution of diatom taxa and lake-water chemistry, as detected by forward selection. Maximum depth (Zntax) and total phosphorus (TP) were transformed by using the In (x + 1) function. This analysis is discussed in detail in reference 46.

Figure 7 shows the results of the calculations. Although temperature trends for lake water chemistry with respect to apatite have not been established yet, it appears that a similar situation may develop for apatite saturation as for the carbonates relative to PCo2 and temperature. 

Methe, B.A., and J. P. Zehr. 1999. Diversity of bacterial communities in Adirondack lakes Do species assemblages reflect lake water chemistry Hydrobiologia 401 77-96. 

The chemistry of lake waters is extremely variable in composition because of the diversity of the watershed lithology, the climatic water balance and the residence time of the water in the lacustrine basin. Therefore, the lake water chemistry is primarily determined by the watershed geology and atmospheric inputs (Campy and Macaire, 2003). Due to this origin, the major ions in lake waters are Ca2+, Mg2+, Na+, K+, Cl, S042, HC03 and C032. Various types... 

Dabakk, E., M. Nilsson, P. Geladi, S. Wold I. Renberg, 2000. Inferring lake water chemistry from filtered seston using NIR spectrometry. Water Research 34 1666-1672. 

In the above studies, lake water is regarded as perfectly mixing one box. However, lake water chemistry is heterogeneous. For instance, chemical composition of surface water differs from deep water. Two box (surface water, deep water) model was applied to the interpretation of P concentration in lake water by Brezonik (1994). 

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