All human activities, including rice farming, have some impact on the physical environment. All rice farms using irrigation have changed the physical environment in some way. For example, dams, rice bays and rice fields change the natural landscape as the natural flow of water is interrupted. Careful water management of rice farms is needed to ensure both environmental sustainability and rice productivity.

Rice products

A healthy farm is a productive farm. Together with the Rice Growers' Association of Australia Inc, rice farmers work hard to maintain an efficient, sustainable and profitable farm. Rice farmers manage their land to be viable in the long term and ensure that the use of natural resources, including water, is sustainable. Rice farmers are also faced with of the following issues:

• rising costs of production
• increased global competition for markets
• changing values of the community with respect to the use and conservation of natural resources, including water
• increased competition for water from other irrigators and urban and recreational water users.

Land and Water Management Plans (LWMP) have been developed by farmers, the wider community and government agencies to minimise the impact of irrigation on environments. Similarly, the Rice Environment Policy is a policy which complements the Land and Water Management Plan with a specific focus on rice production. The policy and its associated programs provide strategies and actions for the rice industry to identify and meet environmental challenges and implement appropriate change.

The future of the rice growing regions and the surrounding physical environments depend on farmers and the wider community implementing strategies at the farm, regional and national levels.

Strategies for efficient water management

The Australian rice industry has improved its water use efficiency (WUE) by 60% in the last ten years. Examples of issues of farming rice and the strategies rice farmers have used to ensure that water is used effectively and efficiently include:

1. Soil suitability
   
• Australian rice farmers carefully plan and prepare their rice fields to make sure that water flows across the fields evenly. Rice farmers and companies make sure rice is grown in soils of low permeability and also carefully plan drainage.
  
• Before a farmer can grow rice they must have their soils tested using both EM31 and physical assessments. If soils are not deemed suitable then rice cannot be grown.
  
• A requirement of the Rice Environmental Policy is that only one third of rice growing land is used at one time. This policy assists in the even distribution of water on the farms, and therefore limits the amount of water permeating the water table. This limited amount of water applied to the farm is called hydraulic loading.
  
• Rice production is also allowed only on heavy, impermeable clay soils, ensuring that it is difficult for water to permeate the water table.
  
2. Water use
   
• Water management on the rice farm is essential for improved water use efficiency. Research, technology, and the implementation of the Land and Water Management Plans (LWMP) have led to improved irrigation farm design and the improved water control, recycling and drainage.
  
• Water use efficiency has also improved as a result of the development of higher yielding, shorter season rice varieties. In early 2003, a new variety of rice was launched that is designed to reduce water use by a further 10%. This assists rice farmers in achieving the greatest rice yield possible with the least amount of water usage.
  
• Australian rice farmers must also adhere to a target water use. This is set each year using a calculation that measures Evapotranspiration (ET) less total rainfall with an allowance of 4 megalitres per hectare for filling and any losses. The average rice farm uses 12 Mega Litres/hectare. Should a rice farmer exceed their target use (i.e. using the above calculation of ET – rain + 4ML) then they are required to attend an interview with the relevant company/authority and face significant penalties.

1. Drainage water quality

Reducing the impacts of rice growing on the natural environment includes programs to minimise the pollution of drainage waters from rice farms. The Australian rice industry is fortunate in that it is free of major foreign pests and diseases and therefore has lower chemical use than many of its competitors. Notwithstanding this, insecticide and herbicide residues and fertiliser from the growing of rice must be monitored very carefully by the rice farmers. Environmental guidelines have been set to limit the amount of contaminants allowed in drainage water from rice farms. For example, for up to 28 days after the application of pesticides or fertiliser to a rice field, rice farmers are not allowed to drain water off the farm. Rice farmers are fined for any breaches of the guidelines.

2. Wetlands

Wetlands within areas surrounding rice farms are important sites for the conservation of flora and fauna. Through the Land and Water Management Plan and the Rice Environmental Policy, there is an aim to monitor and improve the health of existing wetlands and to sustain the biodiversity of the flora and fauna within them.

3. Salinity

The critical salinity issue in rice growing areas is irrigation salinity. Irrigation salinity is caused by rising groundwater which allows salt to rise to the soil surface. The Rice Environmental Policy sets strict guidelines for rice growing. It aims to minimise water leaching into the water table, and resulting soil salinity. To ensure that this happens.

To work with the environment and control salinity, rice farmers use a rotation system of farming and grow other crops or animals as well as rice.

Further Internet resources:

Environment
Water issues
Salinity
National dryland salinity
Department of Land and Water Conservation the Murray river