FerryBox: Using automated water measurement systems to monitor water quality: Perspectives for the Yangtze river and Three Gorges Dam

The building of the Three Gorges Dam (Hubei (湖北) Province, China) has transformed a region with an economy based on sustainable agriculture for millennia into an entirely different environment within an exceptionally short time. This disrupts the natural biogeochemical cycles of carbon, nutrients, and metals and possibly will affect the whole catchment including downstream ecosystems, such as wetlands, estuaries, deltas, and adjacent sea areas. Starting from changes that have already been documented, this article concentrates on the possible use of a “FerryBox”, which is an automated water quality measurement system on board a ship or on shore, to monitor the short and long term development of the quality of the river water in the backwater area and downstream of the dam. While there are already research programmes running to monitor the water quality of the river and the backwater area, these programs are limited to ship campaigns with sampling and laboratory analysis. The spatial and temporal resolution of such measurements is not sufficient for an overall assessment of the water quality and for prognoses in the context of anthropogenic and climate change. Therefore, a concept of applying regular automated observations by a FerryBox is presented. It is shown that such systems are very well suited to give feedback for the assessment of measures to improve the water quality.