Localized Water Quality Improvement in the Choptank Estuary, a Tributary of Chesapeake Bay

摘要: Chesapeake Bay has a long history of nutrient pollution resulting in degraded water quality. However, we report improvements chlorophyll surface waters and dissolved oxygen bottom at one three estuarine stations the Choptank tributary Bay. We updated previous budget for estuary constructed reference year 1998 using rates atmospheric deposition, inputs watershed diffuse sources (primarily agriculture), discharges point human waste) 2017. Parallel trends suggest that quality station were likely due to 20% reductions direct deposition on estuary’s 78–95% wastewater N P installation tertiary treatment. The agricultural sector, dominant source P, appeared provide little contribution improved during this period. Although efforts reduce losses from agriculture are common throughout basin, widespread could make large contributions all estuary. response is similar those observed elsewhere USA, Europe, Australia, New Zealand Similar our findings, upper Potomac River saw driven by deposition. Unfortunately, few studies have shown management. data presented here indicate public industrial investments emissions upgrades treatment plants Choptank.