Tech boost to soil analysis

Management of gravel soils to optimise grain production will receive a boost, with new research to develop rapid and cost-effective technology to measure gravel soil properties.

Crop yields can be limited by soils with more than 20 per cent gravel, which affect nutrient supply, acidification rates, water flow and compaction.

Gravel soils spread across about 3.45 million hectares of the State’s grainbelt and are most prevalent in the high rainfall area.

The Department of Agriculture and Food has started a new project with the University of Western Australia to provide vital knowledge about the composition and influence of gravel soils.

The research is part of a suite of flagship projects under the department’s $20 million Boosting Grains Research and Development initiative, made possible by the Royalties for Regions program.

Project manager, research officer Craig Scanlan said there were three components to the project, which together would provide a better understanding of soil gravels to improve fertiliser strategies and optimise crop potential and profitability.

Dr Scanlan said the first component would marry computer science with agronomic science to improve soil analysis techniques.

“Current methods for measuring the amount and classifying the type of gravel in a sample can be labour intensive and expensive,” he said.

“We intend to use digital image analysis technology, like that used in traffic monitoring and facial recognition, to measure gravel size and distribution and predict the mineralogy in a sample, based on colour, shape and surface roughness.

“The aim is to develop a computerised rapid assessment laboratory technique to classify gravel soils, including the physical, chemical and visual attributes of the sample.”

Another component of the project will develop an in-field method to rapidly measure soil bulk density — the weight-to-volume ratio of a sample, which is a key indicator of soil fertility.

“Existing methods for measuring soil bulk density in gravel soils are time-consuming,” Dr Scanlan said.

“The method we are working on will allow more measurements of bulk density in gravel soils in a day and to more accurately measure compaction in these soils.

“This will also aid future research to improve our understanding of how nutrient and water flow is affected by compaction.”

A third project output will use imaging technology, in association with Professor Mohammed Bennamoun from UWA, to develop a rapid field method that can construct a 3D digital image of the soil profile, after it has been inverted by tillage.

“This project seeks to develop an image analysis technique that will construct a 3D image of the inverted soil structure, which will provide an insight into the vertical and horizontal redistribution of soils during inversion tillage,” Dr Scanlan said.

For more information, visit agric.wa.gov.au and search for “royalties for regions”.