Measuring the extent of coastal benthic habitats is an important indicator of biodiversity, and is essential for the assessment of environmental change. This project aims to; Assess the geomorphology and sediments in order to better identify the distributions of distinctive biological communities; Develop a standardised geomorphological classification system for benthic features that can be applied across the various study regions and nationally; Improve the accessibility to the new acoustic datasets and image products by housing them in a national database linked with OzEstuaries
Develop an improved representation of nutrient sources, transformation and fate in GBR Catchments to assist Regional Bodies with target setting and prioritisation. Outcomes: Knowledge of the sources, transformation and fate of sediment and nutrient in the GBR catchments to assist target setting
“This project will sample and assess the contemporary fertility of typical surface soils from sugar and horticultural lands in sensitive reef catchments. This information will be interpreted in the context of land use, resource condition and trend and current fertiliser and by-product use practices with the emphasis on evidence of need to improve nutrient management practices and avoidance of overuse. Outcomes: • Collation and circulation of soil test diagnostic criteria for levels separating fertiliser response from non-responsive sites
• Assessment of hillslope erosion risk
• Documentation of laboratory methodology for inclusion in to the Australian • Handbook of Soil Chemical Methods
• Survey of findings by crop, catchment and region
• Assessment of the usefulness of ‘traditional’ soil P tests and the Mehlich 3 for predicting soluble P”
“The objective of this program is to mitigate impacts from the GBR catchments in the reef without undermining regional economic and communities. The project will give:
• Integrated regional economic models based on hydrological, ecological and socio- economic data
• Predictive understanding of the functioning of the region’s ecosystem from the perspective of water use – benefits and disadvantages
• Informed policy and investment decisions arising from new analytical capacity
Quantifying of social and economic indicators for use in water benefits accounting derived by the community”
“This task addresses the issue of maintaining marine plant ecosystems and is integral to Program C – Maintaining ecosystem quality. The task will measure the health of marine plant species (productivity) and looking at causative factors influencing health.
This task is of significance to the 25 year Strategic Plan for the GBRWHA, as seagrasses are described as one of the biological communities which the GBRWHA ensures the persistence of (broad area 1. Conservation). This task is necessary to obtain and disseminate accurate and timely information on seagrasses (broad area 4. Research and Monitoring) which will help decision makers (broad area 2. Resource management; broad area 5. Integrated planning) and maximise community confidence (broad area 3. Education, communication, consultation and commitment) in decisions made regarding seagrasses in the GBRWHA.
An outcome will be maps of tropical seagrasses for management of the resource and assessment of possible impacts. Much of the seagrass mapping conducted in the GBRWHA is issue related (e.g. cyclone and flood events, dredging, coastal developments) and requires up-to-date maps for best practice management decisions.”
“Enhanced runoff of terrestrial nutrients (esp. N and P) into the Great Barrier Reef as a result of human land use in the GBR catchment is regarded as a threat to the health and status of reef and coastal benthic ecosystems. As external nutrients are rapidly and largely taken up by phytoplankton, concentrations of chlorophyll a, provide a robust and convenient index of nutrient availability and nutrient-related water quality status. An increase in chlorophyll concentration can be regarded as indicative of increased nutrient availability and eutrophication.
To maintain a watch on regional water quality status and trends within the Great Barrier Reef Marine Park, GBRMPA established water quality sampling sites throughout the park. Basic water quality parameters (temperature, salinity, surface chlorophyll, water transparency) have been sampled have been sampled since 1992 at regular intervals by tourism operators and the Queensland National Park & Wildlife Service. The chlorophyll analyses have been undertaken by AIMS. This task transfers the chlorophyll monitoring program from GBRMPA to the CRC to be managed by AIMS with the intention that the latter will develop a more cost-effective program including satellite remote sensing.”
Nitrogen management is a major challenge facing water quality managers in many parts of Australia. Recent research highlights the importance of nitrogen as the nutrient limiting primary production in some coastal waters and riverine systems. In these situations, an increased delivery of nitrogen is likely to boost algal growth to the detriment of ecosystem health. Increased stream loadings of nitrogen are now recognised as a significant impact of upstream land use in catchments. There is currently a recognised lack of reliable information available to managers to support their decision-making on nitrogen management issues. This is compromising the effectiveness of the very considerable investments now being made in riverine restoration to improve water quality. Riparian buffer zones, particularly those on low order streams, offer the potential for reducing nitrogen entry to waterways, from both surface runoff and shallow groundwater flows. While much of the nitrogen entering streams is attached to sediment in runoff, a significant proportion is often transported in a dissolved form as nitrate. Fluxes of nitrate through the riparian zone are intrinsically linked to water movement (both over and through the soil) and are also strongly influenced by biological processes occurring in that zone. The process of denitrification (microbial conversion of nitrate to nitrogen gas) is particularly important because it effectively removes nitrogen from the riparian zone to the atmosphere. Riparian zone denitrification can have an important impact on downstream water quality when significant amounts of nitrate-enriched groundwater are transported at shallow depths through carbon-rich, anoxic riparian soils, at flow rates that allow enough time for the denitrification process to occur. Outcomes: 1) A simple model for describing denitrification and associated processes in riparian zones; and 2) A methodology for identifying the locations within catchments where these processes may be important. This will enhance the utility of the CRC CH’s Toolkit by adding a new capability to catchment water quality models (such as LEMSS) that describes subsurface fluxes of nitrogen in riparian zones and predicts responses to management change. The research is also very relevant to urban stormwater management and will contribute to the better understanding and prediction of bioretention and subsurface wetland systems.
The objectives of this research are to:
– Make robust estimates of terrestrial inputs of nutrients and sediment to the Great Barrier Reef World Heritage Area (GBRWHA) which appropriately weight the relative contributions of wet, dry, pristine and modified catchments.
– Resolve short-term biological and chemical processes in Great Barrier Reef (GBR) waters which influence the biological availability and uptake of nutrient materials (carbon, nitrogen, phosphate) in river plumes.
– Develop an improved estimate of the fate of nutrient materials (C, N, and P) delivered to shelf sediments as a result of land runoff and related biological production, with emphasis on nutrient burial, recycling and denitrification in nearshore (terrestrial) sediments.
– Use the above information and other appropriate field and historical data, to develop robust, closed models and budgets of nutrient inputs, processing and fates as a basis for comparing human-influenced and pristine shelf regions in the GBRWHA.
– Provide environmental and water quality data essential to the companion task (18.104.22.168): effects of terrestrial run-off on coastal reefs.
– During the course of the above, to maintain long-term water quality monitoring activities in representative sections of the central GBR.
– To provide reef managers and users with timely and appropriate information to assist them in the management and conservation of nearshore reef systems, particularly with respect to the management of enhanced terrestrial run-off.
Monitoring of the intertidal seagrass beds will be carried out to ensure that any change in their status is identified.
Monitoring sites will be associated with the river mouth and inshore marine water quality-monitoring programs to enable correlation with concurrently collected water quality information. Outcomes: Information about current status and long-term (10 year) trends in water quality and marine ecosystem status in the GBRWHA.