The large Lake Wellington Salinity Province has significant areas of high watertables and salinity associated with the low elevation land adjoining the lake and the coastal fringe. An underlying regional scale Groundwater Flow System (GFS) probably plays little part in salinisation processes, with the overlying local to intermediate scale GFSs of the top-most alluvial deposits providing hydraulic connection between the lake and coastal groundwater systems and the adjoining land.
Recharge - discharge processes in combination with land-use choices have influenced local salinity outcomes, particularly where the natural vegetation has been cleared. The indigenous vegetation cover was adapted to the prevailing groundwater conditions, but replacement with pasture species resulted in land and soil degradation due to the combination of low elevation land, brackish groundwater and a high watertable.
Suggested management actions include improving irrigation efficiency in the adjoining Macalister province, increasing perennial pasture use in grazing farms and treating salinised areas with fencing and salt tolerant vegetation. Severely degraded areas should be returned to tidal wetlands and revegetated.
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