Land-Sea Linkages

Description

River mouths and estuaries can be highly productive habitats that support biodiversity and potentially targeted species for commercial, recreational, and cultural purposes. Productivity in the inshore environment is sensitive to terrestrial runoff that generates turbidity, deposits sediments, and subsidises marine carbon and nutrient pools. While the western Kimberley is among the most pristine environments in Australia, abundant water and energy resources will likely be developed in the near future with important implications for linked river, estuarine and inshore environments.

Aims

To develop catchment-based modelling tools that estimate freshwater discharge and the delivery of carbon and nutrients to inshore coastal environments that will provide an improved understanding of relationships between river flow and coastal ecology by:

• Estimating how much water flows from Kimberley rivers to the coasts;
• Estimating fluxes of organic carbon from Kimberley rivers to the coasts; and
• Developing models for important river and coastal processes.

Methods

• Rainfall records and current gauging stations were used to estimate freshwater flow from major Kimberley rivers into the coastal waters each year
• Samples of river and coastal water to measure water and sediment properties were collected.
• A coupled physical-biogeochemical model and a catchment carbon export model were developed to understand the link between exported material and coastal productivity
• Collaboration/partnerships were established with Indigenous communities to help understand annual cycles and to train indigenous rangers in sampling techniques

Outcomes

• Kimberley catchment responses are dominated by the seasonality of rainfall and the inter-annual climate variability
• Estimates of the annual freshwater run-off from rivers to coasts
• Estimates of the amount of organic matter supplied from the land to the coast and some understanding of what happens to it in the coastal zone
• Models of what role material from the land plays in coastal ecosystems

Project News

Kimberley coastal system: links from the land to the deep sea (WAMSI June 2016)

Reports

Jones NJ, Patten N, Krikke D, Lowe R, Waite A, Ivey G (2014) Biophysical characteristics of a morphologically-complex macrotidal tropical coastal system during a dry season. Estuar Coast Shelf Sci 149: 96–108. doi:10.1016/j.ecss.2014.07.01

Media

Presentations

Terrestrial-Ocean Linkages in the Kimberley (2017 WAMSI Research Conference)

Hydrodynamic and Biogeochemical Controls on Productivity in the Kimberley Coast. (Parks and Wildlife Lunch and Learn seminar).

Land-Sea Linkages in the Kimberley (2015 WAMSI Research Conference)