Farm community involvement in acid soil management in southwest NSW

September 2003

Twenty four Landcare groups and 600 farmers in south west NSW combined to demonstrate the extent and severity of soil acidification in their area and advance acid soils as an environmental issue with farmers and government. The project was conducted by the SW Slopes Community Acid Soils Group made up of farmers from the Landcare Groups.

The project had three objectives:-

1. To inform farmers about their soil, acid soil management and acid tolerance of their crops as well as assist them to decide on individual liming programs.

2. To inform Landcare groups about soil fertility in their area.

3. To highlight the issue of soil acidification within the community and governments.

The project commenced in 1997 with farmers collecting samples from the 0 - 10 cm and 10 - 20 cm soil layers from over 5500 paddocks in an area ranging from Tumbarumba in the east to Urana in the west.

Sample analysis showed that the average surface soil pH(Ca) was 4.6 and declining. The 10 - 20 cm soil layers were equally if not more acid than the surface layers across most of the sampled area.

The soil pH, exchangeable aluminium and cation exchange capacity for both the 0 - 10 cm and 10 - 20 cm soil layers were mapped for the project area. Other original and derived data such as Soil P and stocking rates were also mapped.

As a result of this project the Murray and Murrumbidgee Catchment Management Boards have included better management of acid soils in their Soils Health Targets.

Soil Club Visit to Young

2003

Fifty people attended a seminar in Young, NSW recently, to further their knowledge on the importance of biological fertility to soils and the physical, chemical and biological indicators of soil health. Professor Lyn Abbott, from The University of Western Australia presented the seminar in response to a request by ASC member Mrs Rhonda Daly.

Professor Abbott's research in the field of soil science and plant nutrition spans 30 years. Much of her research has been about arbuscular mycorrhizal fungi.

More recently, soil biology research at the University of Western Australia has been focusing on how best to use information about soil organisms for soil management on farms and in vineyards. Various research projects are funded by GRDC, RIRDC and GWRDC and the overall aims are to convert complex scientific information into practical information for use by land managers.

Information about soil organisms is only relevant in the context of soil physical and chemical processes and one of the purposes of the Australian Soil Club is to attempt to clarify the interconnections between these components of soil fertility. Soil texture has a great impact on the habitat of soil organisms. Therefore, understanding how the textures of different soils influence soil biological activity is an important research area. Any factor that affects soil texture will affect soil organisms to some extent. However, soil organisms can also have an effect on the arrangement of some soil particles through the exudates produced by fungi and bacteria and also by activities of soil animals.