Understanding the pressures on the marine environment and their change over time is an important part of developing and prioritising management actions.
IMAGE: Example of collated pressure data for Commonwealth waters. Image: CSIRO. Change in seismic surveys (red: pre-1996; blue: 2006─2010). The collated data show the extensive surveying done before 1996, and the reduced seismic footprint in later years.
In the past, however, pressure data have not been collated, nor provided in formats that made them easy to compare. In addition, commercially sensitive data have often not been available for general display. This project mapped environmental pressures in Commonwealth waters (such as fishing, shipping, seismic surveys and oil and gas infrastructure) on a national scale and identified the associated risks and impacts in relation to marine biodiversity. The resulting capacity to assess the impacts of human activities on the marine environment will help the Department of the Environment to assess cumulative and relative impact and risk, and support the implementation of marine bioregional plans.
Approach
Existing data and information on key threats were sourced from the Commonwealth Environment Research Fund Marine Biodiversity Hub (the forerunner of the NERP Hub), national bioregional planning, CSIRO marine indicator and threat mapping projects, the Integrated Marine Observing System and the Australian Fisheries Management Authority. The data were analysed or aggregated to improve interpretation. For example sea-surface-temperature data were analysed and presented as long-term change, and commercial fisheries data were aggregated to obscure individually-confidential data points.
The distribution of pressures was mapped, and options were explored for combining qualitative and quantitative analyses of impact. Approaches and statistical tools were developed to investigate interactions between biodiversity assets and pressures and between multiple pressures as a stage in the development of cumulative impact indices.
IMAGE: SHIPPING ACTIVITY AND SEISMIC SURVEYS: All shipping activity for shipping greater than 200 tonnes around Australia: 2006─2010 (green to red, low to high activity) and the sum of all the seismic surveys for the same period (blue).
IMAGE: SEA-SURFACE TEMPERATURE CHANGE: Estimated sea-surface temperature average long-term linear change, (°C per decade). Areas of orange and red indicate warming during 1993–2013 (south-western Australian and eastern Tasmania); areas of green and blue indicate cooling (eastern Australia and northern Australia).
ABOVE: Examples of collated pressure data for Commonwealth waters. Images: CSIRO.
New knowledge and opportunities
A simple data viewer was developed and deployed on the NERP Marine Biodiversity Hub website to provide simple access for Departmental staff to all the outputs of the Hub, including the pressure maps.
Pressure maps were aggregated and displayed in five-year bins to match the State of the Environment reporting interval and to allow straightforward assessment of whether the footprint for individual pressures had increased or decreased in the past few decades.
Outputs and outcomes
One hundred and twenty six different layers of pressure data, with associated metadata records, have been collated for the Commonwealth Marine Reserve network. They include summaries of the current status of oil and gas extraction and infrastructure, seismic surveys, shipping movements, aquaculture leases, pollution events, trends and variability in changes on ocean temperature. The data have been archived on the Australian Ocean Data Network to ensure their long-term availability to Departmental databases.
contact
Piers Dunstan
piers.dunstan@csiro.au
(03) 6232 5382