Groundwater resources in the southwestern United States are finite and riparian and wetland areas are vulnerable to aquifer overdraft and unregulated groundwater use. Environmental isotopes and water chemistry were used to distinguish water types, recharge mechanisms, and residence time along several reaches of the Sonoyta River and Quitobaquito Springs located near the U.S.-Mexico border. Areas located upgradient from the Sonoyta River, such as the Puerto Blanco Mountains and La Abra Plain, are supported by local recharge which corresponds to water from the largest 30% of rain events mainly occurring during winter. For Quitobaquito Springs, the δ18O and δ2H values are too low to be derived from local recharge. Stable isotope data and Cl/SO4 mass ratios indicate that the Sonoyta River supplied Quitobaquito Springs through flow along a suggested fault system. Based on these results, Quitobaquito Springs flow could be diminished by any activity resulting in increased groundwater extraction and lowering of water elevations in the Sonoyta River regional aquifer.

中文翻译：

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美国-墨西哥索诺伊塔河流域的地下水同位素：对基多巴基多泉的补给源和管理的影响

美国西南部的地下水资源有限，河岸和湿地地区容易受到含水层透支和地下水使用不规范的影响。环境同位素和水化学被用来区分位于美国和墨西哥边境附近的索诺伊塔河和基多巴基多泉的几个河段的水类型、补给机制和停留时间。位于索诺伊塔河上游的地区，如波多黎各布兰科山脉和拉阿布拉平原，由当地补给支持，相当于主要发生在冬季的 30% 的最大降雨事件的水。对于 Quitobaquito Springs，δ18O 和 δ2H 值太低，无法从当地补给中推导出来。稳定同位素数据和 Cl/SO4 质量比表明，索诺伊塔河沿着建议的断层系统通过水流供应基多巴基多泉。根据这些结果，任何导致地下水开采增加和索诺伊塔河区域含水层水位降低的活动都可能减少基多巴基多泉的流量。