The Lismore Salinity Province adjoins the north of the Lake Corangamite Province and has nearly 3% mapped salinity. It occurs mostly on the Pliocene sedimentary local Groundwater Flow Systems near the Derrinallum – Lismore area. The most at risk areas are depressions and drainage lines leading towards Lake Corangamite, as well as similar low-lying areas on the basalt plains in the east of the province.
Unlike other Salinity Provinces in the Lake Corangamite area, salinity in this province appears to be more secondary salinity than naturally occurring or primary salinity that resulted from raised groundwater levels that followed clearing for agriculture.
Management approaches should endeavour to increase plant water use in pasture and cropping areas near depressions and drainage lines where waterlogging and salinity have been mapped. Improved surface drainage may have exacerbated soil salinisation in some low-lying areas by removing seasonal freshwater ponding, but re-instatement of wetlands will be suitable in only limited circumstances.
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