Anthropogenic sulfate loads in the Rio Grande, New Mexico (USA)

摘要: Abstract The sources of SO 4 along a ~ 550 km stretch the Rio Grande in New Mexico and western Texas were investigated using stable S isotopes. During 2007 2008, δ 34 dissolved surface water varied over narrow range from − 1.6 to + 0.9‰, which was consistent with local fertilizers (− 2.1 + 1.6‰) not Paleozoic evaporite regional bedrock (+ 7.6 + 12.9‰). This is likely due fact that major component N–P–K used Valley, constituting about half total by mass. /Cl ratios groundwater system are relatively low (0.06 3) compared fertilizer source, suggesting more Cl added geological as . In Mesilla Basin southern Mexico, we identified zones mixing between recharging irrigation within depth ~ 50–200 m below ground surface. For this aquifer, Principal Component Analysis (PCA) indicated Na–K–Cl concentrations largely attributable –Mg–Ca anthropogenic sources. Here, an additional source (with − 2.7‰) linked anaerobic decomposition manure on horse farm. case (800 mg/L) increased three times background ( 2 manufacturing, fluxes rivers shallow aquifers waters can be significant worldwide.