Sustainability Indicator for Water and Land Resources

An indicator was designed to represent the sustainability of a reservoir water supply system, and a simulation procedure was established to evaluate the indicator. The indicator was defined by potential water supply and water demand. The simulation procedure includes potential water supply assessment, streamflow simulation, and designed water demand. The procedure was applied to the Tsengwen reservoir water supply system in Taiwan. Three upstream land use scenarios, three water demand cases, and four climate scenarios (current and three climate change conditions) were considered to evaluate their effects on sustainability. Simulation results indicate that the converting forest to agricultural land will reduce sustainability, and climate change will also have negative effects. Considering increase of water supply for coastal area will dramatically decrease sustainability. At the end of this paper, an idea for developing an integrated indicator was proposed for further study.