Land and Water Link

September 2002

Efficient Water Use for Agriculture in Australia and China How can precious soil and water be managed efficiently for agriculture without depriving other aspects of the environment? And how do you achieve a balance between production and environmental impacts when drought or flood could be just around the corner?

These complex questions were addressed during a four-year Australian aid project with China (1997–2001) part-funded by the Australian Centre for International Agricultural Research (ACIAR). The research project, aimed at finding solutions to serious soil and water problems in major agricultural regions in Australia and China, brought together scientists from CSIRO Land and Water and the Chinese Academy of Sciences.

Together, they created a common language across cultures and scientific disciplines to develop an integrated understanding of the landscape. This understanding was used to create guidelines to minimise the negative effects of agriculture on soils and increase efficient water use – or maximise the kilograms of agricultural yield per hectare of land per millimetre of water. The results are expected to fine-tune agricultural practices in Australia and China.

According to Dr Tim McVicar from CSIRO Land and Water, 'The issues and environmental pressures in Australia and China have a lot of similarity – we all want to maintain agricultural activity without flogging the environment'. The ACIAR project focused on the development of a suite of models and information systems to help farmers. Researchers modified a water balance model called WAVES to estimate factors that contribute to water use efficiency. They also developed soil impact models to link an understanding of soil process with both the water in the soil and the underlying geology for sites in Australia and China. Spatial information systems were used to 'upscale' point measurements for water balance and soil impacts to regional areas.

'Technology transfer involved the exchange of skills between scientists', says Dr McVicar. 'Another outcome was a set of manuals written for farmers, which explained the underlying scientific concepts. These were distributed through existing extension networks.' In addition, policy makers now have access to a series of environmental indicators for water, soil, the atmosphere and the oceans, published in Chinese. These are aimed to assist planning efforts at local, regional and national levels. The project focused on three important agricultural regions in Australia and China:

• Murray-Darling Basin in southeast Australia, which has agricultural problems caused by salinisation, waterlogging and sodicity caused by rising saline groundwater
• North China Plain, which faces increased pressure to maintain agricultural production because of soil degradation (salinity, sodicty and seasonal water logging) and declining regional groundwater
• Loess Plateau, to the west of the North China Plain, which has agricultural problems due to a lack of water for crops, and soil erosion. (The Yellow River is named after the colour of the Loess Plateau sediment).

Aspects of this collaborative project are at the cutting edge of agricultural research. For example, methods were developed to map and monitor water and soil attributes across extensive regions for the first time. Regional water use efficiency – a concept of increasing importance to Australia's natural resource managers – was assessed for 60,000 km2 in China. 'We developed new methods to take information from detailed experimental plots where people make measurements the size of your lounge-room and 'upscale' it to tens of thousands of square kilometres across the North China Plain', observes Tim McVicar. 'The scientists we collaborated with in China now have the skills to routinely develop a measure of water use efficiency across vast geographic areas.' This was possible in China, as the researchers had access to a database with consistent crop yield data and irrigation levels (the amount of water that was pumped from the groundwater over the growing season at a county level).

Dr Rob Fitzpatrick and his group from CSIRO Land and Water were also involved in the design of guidelines for farmers. Having studied soil sodicity, salinity, and erosion and their impacts on water quality in the Adelaide Hills, these researchers have created a set of guidelines that can be easily applied elsewhere and are useful to all resource managers, whether they be farmers, catchment coordinators or policy makers. The findings from this collaborative project are now available in a book, Regional Water and Soil Assessment for Managing Sustainable Agriculture in Australia and China edited by Tim R McVicar, Li Rui, Joe Walker, Rob W Fitzpatrick and Liu Changming. Hard copies can be purchased from the previous link or from CSIRO Publishing.

For further information

Contact
Dr Tim McVicar
Ph: 02 6246 5741

Dr Rob Fitzpatrick
Ph: 08 8303 8511