Understanding the impacts of catchment characteristics on spatial variability in water quality: a case study in the Great Barrier Reef catchments

Water quality monitoring programs often collect large amounts of data with limited attention given to the assessment of the dominant drivers of spatial and temporal water quality variations at the catchment scale. This study aims to: a) identify the influential catchment characteristics affecting spatial variability in water quality, and b) develop predictive models to estimate average concentration of water quality constituents. Tropical catchments in the Great Barrier Reef area, Australia were used as a case study. Water quality monitoring data (i.e. sediments, nutrients and salinity) from 32 sites together with 58 candidate catchment characteristics were used to construct statistical models. This data set contains 58 catchment characteristics and 9 time-averaged water quality constituents' concentration at 32 GBR catchments.