Erosion and run-off of fertilised urban and agricultural land, and discharges from Sewage Treatment Plants (STPs) can result in increase in nutrient loads to waterbodies. Nitrogen and phosphorus are the nutrients of greatest concern. Some species of algae and algae-like bacteria are particularly good at utilising nutrients and form ‘bloom’ when nutrient levels and other conditions are favourable. Blooms can have human health, amenity and odour risks. Blooms can also result in fish kills and threaten aquatic plants by reducing light penetration.
View a conceptual model of potential causes of a change to nutrients and the condition responses observed as a result of this change.
Potential indicators
There are a number of causes and symptoms related to this stressor. The following indicators are recommended for the stressor ‘Nutrients’:
Pressure indicators
Indicators of nutrient sources:
- Catchment land-use
- Percentage length of river system with no riparian vegetation
- Percentage of catchment with intensive agriculture on steep slopes
- Nutrient concentration of sewage treatment plant wastewater
- Frequency of sewage overflow events
- Number of point sources (excluding STPs) per km estuary
- Percentage of catchment with less than 70% ground cover
- Number of stormwater inflows per km estuary
Indicators of direct pressure:
- Percentage difference between pre-European total phosphorus load and current load
- Percentage difference between pre-European total nitrogen load and current load
- Total nitrogen load
Vulnerability indicators
- Flushing rate and water clarity
Condition indicators
Physical-chemical condition indicators:
- Ammonia
- Organic nitrogen
- Oxidised nitrogen
- Total nitrogen
- Filterable reactive phosphorus
- Total phosphorus
Biological condition indicators:
- Chlorophyll-a
- Percentage epiphytic cover on seagrass
Possible causes | Possible symptoms |
The actions/events/situations that might induce this stress: | The actions/events/situations that might arise from a change to the stressor: |
Background science
Other information on nutrients
International
Global Environment Monitoring System (GEMStat) is designed to share surface and ground water quality data sets collected from the GEMS/Water Global Network, including over 1,400 stations, two million records, and over 100 parameters.
Australia
Australian Natural Resources Atlas. One of the key information delivery mechanisms for the National Land and Water Resources Audit. Search the Australian Natural Resource Atlas for information about surface water quality monitoring programs in Australia
Australian Natural Resources Data Library. You can search for metadata (data about data) here
Simple Estuarine Response Model II (SERM) website contains summary statistics of coupled biological – physical estuarine models as applied to over 700 Australian estuaries. The results of these simulations, along with the original ‘generic’ SERM simulations, can be accessed interactively using the SERM II interface
ACT Waterwatch.The Waterwatch database program allows you to enter your Waterwatch data and store it as a record or file; develop graphs and produce short reports about your data; and perform simple analyses on the Waterwatch data you have collected from your catchment. It can be downloaded from this site.
New South Wales
Streamwatch – Australian Museum. This site has water quality data available from different regions throughout New South Wales are available for most Streamwatch sites.
Waterwatch NSW. Choose a Waterwatch site from an interactive map of New South Wales. Water quality data are available for most Waterwatch sites.
Waterinfo. The NSW Department of Infrastructure, Planning and Natural Resources has over 200 datasets of water quality results from discrete samples. This page provides a list of stations with links to discrete water quality data available for each station. Data is updated weekdays overnight.
Queensland
Coastal Habitat Resources Information System (CHRIS). Interactive maps showing coastal habitats, with options for showing water quality monitoring data.
Department of Natural Resources and Mines. Data on the ambient quantity and quality of the State’s freshwater resources in streams and aquifers is available to the public in digital format under a range of fee and access arrangements
Ecosystem Health Monitoring Program (EHMP) have water quality maps of Moreton Bay and its river estuaries. Choose to view monthly water quality maps, seasonal medians or animations for each month.
Queensland Government – Water Monitoring Information Portal. This web site provides access to gauging station information, streamflow data summaries and chemical analyses of water samples from the surface water data archive.
Waterwatch Gold Coast. This site provides some water quality data from the Waterwatch program, from a number of creeks in the Gold Coast Region ( Gold Coast Waterwatch )
Tasmania
Water Information Resources & Electronic Data (WIRED) is a joint State and Federally funded system providing on-line access to a range of water information products including water management policies, current river levels and flows, catchment reports, and data summaries for individual sampling/flow sites.
Waterways monitoring reports from Tasmania’s rivers and streams provide current data on streamflow, water quality and riverine health for 2004. They can be downloaded from this page.
Victoria
Catchment Indicators Online Provides current information about the management and changing condition of Victoria’s land and water resources.
Murray-Darling Basin Commission’s Water Quality Monitoring Program Information about this program can be found on this site. It has water quality data from the Murray Darling Basin for the years 1994-1995
Water Measurement Information System. This site combines data from a number of community and scientific based monitoring programs into one easily accessible resource. Data includes suspended solids and turbidity.
Western Australia
State-wide assessment of river water quality. Click on a drainage basin to access water quality data. Data is presented on maps.
Models
Australia
Computational Aquatic Ecosystem Dynamics Model (CAEDYM) consists of a series of mathematical equations representing the major biogeochemical processes influencing water quality, including primary production, secondary production, nutrient and metal cycling, and oxygen dynamics and the movement of sediment.
Catchment Modelling Toolkit is a repository of software and supporting documentation intended to improve the efficiency and standard of catchment modelling.
International
US EPA Water Quality Models. The U.S. Environmental Protection Agency provides links to a number of water quality models for simulating the movement of precipitation and pollutants from the ground surface through pipe and channel networks, storage treatment units and finally to receiving waters.
USGS Hydrologic and Geochemical Models are widely used to predict responses of hydrologic systems to changing stresses, such as increases in precipitation or ground-water pumping rates, as well as to predict the fate and movement of solutes and contaminants in water.