Land-sea connectivity, ecohydrology and holistic management of the Great Barrier Reef and its catchments: time for a change

The Great Barrier Reef (GBR) is an iconic and highly valued ecosystem in Queensland, Australia that is recognised internationally for its natural and cultural values. The coastal and marine ecosystems of the GBR are interconnected with the adjacent catchment area through hydrological connections. However, many GBR ecosystems are in a poor state, driven by several factors including a highly modified catchment. Land use changes over the last 160 years have led to development of agricultural land uses, modification of the coastal floodplains and loss of freshwater wetlands, and disruption of drainage and hydrological connections. These ecohydrological changes have led to declining water quality in catchment waterways and increases in the loads of pollutants that are delivered to the GBR, which predominantly occurs in wet season rainfall events. The Australian and State governments have recognised the need to address water quality issues for the GBR through management of the catchments, however, the management strategies adopted to date are largely associated with improvement of agricultural management practices and are not likely to be enough to maintain or restore the health of the GBR ecosystems. Future management strategies need to take into the account the need to protect, maintain and restore coastal ecosystems, system functions and land-sea connectivity if the values of the GBR are to be retained in the long term.