Lynx Creek, a small intermittent creek in the Bradshaw Mountains of Arizona, is subjected to drainage from an abandoned copper mine. The mine‐drainage decreases the pH of the Creek about three units and greatly increases sulfate and heavy metal concentrations. Chemical recovery of the Creek occurs downstream through precipitation of metal hydroxides and dilution by tributaries. Changes in Creek chemistry are accompanied by changes in algal flora. Above the mine and downstream after substantial recovery, the flora is dominated by Tribonema affine4, Achnanthes spp., and Synedra ulna and several zygnematacean species. In the mine seep entering the Creek and in the Creek just below the seep the flora is reduced in species richness and dominated in abundance by Microthamnion kuetzingianum and Eunotia tenella.

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Drainage from an orphaned copper mine (Sheldon Mine Complex) contributes highly mineralized, acidic waters to Lynx Creek, a small intermittent, arid-climate stream . This results in localized elevation of major cations, silica, sulfate, and heavy metals (Cu, Fe, Mn, Zn), depression in pH, and complete neutralization of bicarbonate alkalinity . Levels of chloride, nitrogen and phosphorus are unaffected by mine-drainage . During stable flow, water quality of the creek improves downstream through precipitation of metal salts, dilution by less mineralized tributaries, and additional buffering from the creek channel and tributaries . Climatic aridity, via high evaporation, concentrates and precipitates metal salts during summertime periods of low flow. Creek sediments thus contain large amounts of heavy metals and phosphorus that are transported downstream in suspended particulates during spates . This reflects an annual cycle of temporary creek-bed storage followed by episodic mobilization toward Lynx Lake, a downstream reservoir . Although the influence of mine drainage is not overtly apparent in the dissolved chemistry of the Lake, high concentrations of metals and phosphorus occur in lake sediments .