Investigating best management practices to reduce selenium and nitrate contamination in a regional scale irrigated agricultural groundwater system : Lower Arkansas River Valley, southeastern Colorado
The Lower Arkansas River Valley (LARV) is well known for its rich agricultural production, with 109,000 ha of irrigated area. Due to agricultural production extending for more than 100 years, the LARV now faces challenges of soil salinity, water logging from shallow groundwater tables, and a high concentration of selenium (Se, both within the alluvial aquifer system and within the Arkansas River and its tributaries). Se originates primarily from bedrock and outcropped marine shale, released due to chemical oxidation in the presence of dissolved oxygen and nitrate. Se is a dynamic element that ...