Viable pasture and cropping agronomic packages for mildly/periodically saline land
This project aims to assess production options for mildly saline land, as well as areas affected by the invasive slenderleaf iceplant (Mesembryanthemum nodiflorum) for implementation or expansion of future pasture and cropping enterprises.
National Landcare Program (NLP) Community Support Component
Project lead organisation
Department of Agriculture and Food Western Australia (DAFWA)
In 2006, the Liebe Group, in partnership with DAFWA, was successful in obtaining funding from the NLP Community Support Component to implement a project aimed at assessing production options for mildly saline and slenderleaf iceplant affected land.
Within the shires of Morawa, Perenjori, and Dalwallinu, there is currently 190,000 hectare of salt affected land, with a further 530,000 hectare considered 'at risk' of salinification in the next ten years. This land is regarded as a poor option for grazing, principally due to the high infestations of slenderleaf iceplants. These are highly toxic to stock and have caused considerable sheep deaths.
Landholder perceptions remain that all salt affected land is unproductive purely due to the high salt concentrations. Increasing amounts of land are being continuously lost, particularly after high rainfall years. Many farmers cease cropping and discontinue any farming management practices in these paddocks once they notice salinity levels rising.
As a result, these areas are rapidly colonized by iceplants and rendered unproductive, unsuitable for grazing due to the monoculture of toxic plants. These out-compete most good pasture and other saltland species, allowing little else to grow. This species is suspected of mobilising salts within the soil profile to the surface, through its abiliy to uptake and store salts.
Several key objectives of this project include:
Investigating the ability of iceplants to draw salt from depth to surface soils (i.e. plant tissues analysis).
Development of benchmarks and diagnostic processes allowing landholders to undertake paddock-based tests that accurately determine the salinity status of a given area. Benchmarks will be developed through field investigation of site salinity characteristics and stored in a database.
Research cultural or herbicidal control methods for the toxic exotic weed slenderleaf iceplant (M. nodiflorum). Develop complete weed control packages that include saltland species on current herbicide registrations.
Trial/demonstration of existing soil ameliorant technologies, such as gypsum application and deep ripping, to alleviate soil structure decline due to salinification and/or sodification.
Extend project information to growers in the aim of developing a more positive mindset about how moderately affected saline land can be managed. This will be carried out through the provision of pamphlets, field days, articles in local newspapers, and other methods. Published results will also be extended to the wider agricultural community through the support that has been shown by the various grower and NRM groups.
This issue of inhibited agricultural production on mildly saline land has become increasingly important in light of the recent data regarding water table declines due to global warming and/or reduced rainfalls. Potentially, much of the land that has become saline in the past 50 years may well be returned to production as saline water tables decline. This does rely on good weed control and specific agronomic development for this land class.
Results and Reports
This project was funded by the National Landcare Program Community Support Component.