The large West Dundas Tablelands Salinity Province is underlain by a variety of bedrock geologies, covered by a deeply weathered regolith that has resulted in a complex landscape of local Groundwater Flow Systems (GFSs) overlying a little known regional GFS. Historical mapping identified some saline waterways and lakes as primary salinity features in parts of the province and high watertables were naturally present in some low-lying parts of the landscape. Many of these were expanded by secondary salinity following the loss of perennial native vegetation, which resulted in brackish groundwater emergence along many drainage lines.
The mapped dryland salinity is predominantly found along the many shallow drainage depressions that dissect the tableland, where it has sometimes resulted in an important ecological vegetation class identified in the Regional Vegetation Management Plan.
Treatment of saline discharge areas with suitable waterlogging and salt tolerant perennial plants should aim to reduce soil structure damage and erosion, especially in areas with sodic soils. Recharge treatment cannot be targeted to specific areas so any general increase in plant water use across cropping, grazing and forestry recharge areas will help in wet years.
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