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Nitrate sensor at the Frio River at Concan, Tex.

2017 (approx.)

Detailed Description

Back cover photo from
Opsahl, S.P., Musgrove, M., Mahler, B.J., and Lambert, R.B., 2018, Water-quality observations of the San Antonio segment of the Edwards aquifer, Texas, with an emphasis on processes influencing nutrient and pesticide geochemistry and factors affecting aquifer vulnerability, 2010–16: U.S. Geological Survey Scientific Investigations Report 2018–5060, 67 p.,


Public Domain.