Long-term trends of Great Lakes major ion chemistry

Lake Michigan: Nearshore variability and a nearshore–offshore distinction in water quality

“…The change has been occurring in synchrony ( Fig. 6) with the long-term changes observed in offshore waters (Barbiero et al, 2002(Barbiero et al, , 2012Mida et al, 2010;Chapra et al, 2012). Past management decisions (De Pinto et al, 1986) appear to have reduced some of the loading going to Lake Michigan as observed in long-term decrease in nearshore and offshore water quality parameters such as TP and chlorophyll a.…”

“…Oscillatory exchange of Lake Michigan with Lake Huron through the Straits of Mackinac may provide a dilution effect to specific conductivity (and other parameters) and extend up to 70 km into the northeastern part of Lake Michigan (Saylor and Sloss, 1976;Anderson and Schwab, 2013). Dilute water consisting of a mixture from Lake Huron and Lake Superior (St. Mary's River) is likely exchanged through the straits and results in lower specific conductivity (Chapra et al, 2012).…”

The Potential for CO2-Induced Acidification in Freshwater: A Great Lakes Case Study

“…They can be performed using laboratory manipulations, mesocosms, and in situ CO 2 perturbation experiments (Fabry et al, 2008). For the Laurentian Great Lakes, one particular genus that should be studied across its life stages is the dreissenid mussel, as these mollusks have significantly shaped the ecosystem since their invasion (Fahnenstiel et al, 2010;Nalepa et al, 2010;Chapra et al, 2012), greatly stress the already-declining native mussels, and make their shells out of aragonite.…”

A science plan for carbon cycle research in North American coastal waters. Report of the Coastal CARbon Synthesis (CCARS) community workshop, August 19-21, 2014

“…Biogeochemical differences among the lakes are large. For example, Table 2 shows that mean alkalinity varies by more than a factor of two among the lakes, which is largely a reflection of different geologic settings (Chapra et al, 2012). Consistent with their huge economic impact, the LGL have a long history of anthropogenic impacts followed by remediation and degrees of recovery.…”

“…Successful management of phosphorus inputs has decreased primary production (PP) in the open waters of all of the lakes (e.g., Chapra et al, 2012;Mida et al, 2010;Bunnell et al, 2014). Nitrate has risen in response to atmospheric deposition, as well as in-lake cycling (e.g., Sterner et al 2007;Chapra et al, 2012).…”