The behavior of Fe and Mn is more complicated in that they GSK1349572 increase significantly in river water

downriver during storm flow, but not during baseflow conditions. While the reason for this is unclear, they may be preferential leached from soil profile during precipitation events due to interaction with lower pH waters. Zinc decreases in concentration in river water downriver during both stormflow and baseflow events suggesting the production of zinc hydroxide as the pH rises slightly downstream (Table 2, Fig. 3 and Fig. 4). All anions are found at greater concentrations in baseflow than stormflow river waters, except for nitrate. During storm flow positive correlation coefficients were found for NO2 (0.44) and CO3 (0.46) indicating downriver increases in concentration, while NO3 (−0.36) and PO4 (−0.45) decrease downriver (Table 2, Fig. 4). During baseflow negative correlation coefficients were found for F (−0.35), Cl (−0.18), and SO4 (−0.19), indicating a decrease in concentration downriver while the other anions increase, although much variability is seen between sampling sites. The concentration of virtually

all anions, except nitrate, and specific conductance were enriched during base flow conditions compared to stormflow (Table 2, Fig. 4). Nitrate was 3.64x more concentrated in river water during stormflow; compatible with an origin from precipitation. Aurora Kinase In contrast, mean sulfate concentrations in river water were the same during stormflow

and baseflow. Taken together with the element GW 572016 data presented above this data suggests the greater rock/water interaction during baseflow conditions enhances bedrock derived anion concentrations and the concentrations of divalent cations in Raquette River waters. Fig. 5 compares the concentration of select elements for three sampling events of varying discharge, including samples taken during low (143 cfs) and high (1990 cfs) flow conditions for this study. The intervening value of 1190 cfs, represents a flow duration percentile of 41.3% (“normal” flow) and was collected on June 5th, 2008. The normal flow samples compared in Fig. 5 were collected at the same sites as the stormflow and baseflow samples representing the Adirondack Highlands (JF), Adirondack Lowlands (FI), and St. Lawrence River Valley (SL) along the Raquette River. Fig. 5 shows the relatively insoluble trivalent (Al, Ce, Fe) elements generally have the least variation in concentration during periods of “normal” or near average flow (i.e. pinch inwards at 1190 cfs). In contrast, the more soluble divalent and monovalent (Ca, Mg, K, and Na) elements generally show the greatest variation in concentration during “normal” flow conditions (bulge outwards at 1190 cfs).