The Northern and Yorke NRM Region

This NRM region extends from the southern tip of Yorke Peninsula, northward along the western coast of Gulf St Vincent, incorporating Ports Wakefield and Pirie and up to Quorn in the southern Flinders ranges. The region has a climate of mild wet winters and hot dry summers. Average annual rainfall ranges from 630mm in the Clare Valley to 500mm at Maitland and 330mm at Quorn in the north. Agriculture is the principal industry across the region and thus the soil is the critical asset. The primary crops are wheat, barley, canola and a range of legumes (field pea, chickpea, lentil, faba bean). Lucerne and oaten hay production is also an important industry along with meat and wool. The Clare Valley hosts an important grape and wine production industry.

The region is made up of three major landforms. Yorke Peninsula is a gently undulating plain with central rises and low hills. Soils are largely loam over clay, shallow calcrete or calcareous loams with some areas of dunefields and saline land. Wind and water erosion, soil fertility and salinity are the main degradation issues. On the coastal plain, shallow calcrete and calcareous loams over highly calcareous unconsolidated deposits, and dune-swale and sand spread complexes also occur. Wind erosion is a major issue on these plains, as well as the broad occurrence of saline surface soils. Subsoils are commonly moderately saline, sodic and alkaline, reducing plant root depth and water use efficiency. In the hill and valley landscapes of the northern Mount Lofty Ranges and Southern Flinders Ranges, the neutral loamy soils over red clay subsoils are highly susceptible to water erosion. There are also numerous small areas of dryland salinity across the region in the higher rainfall areas, reflecting shallow local watertables. Many of the valley flats, particularly those with a history of lucerne, and other areas of high productivity and intensive use, require regular lime application to prevent loss of productivity and permanent soil damage from acidification. Subsoil salinity, alkalinity, sodicity and boron are widespread, restricting root growth and water use efficiency. Some parts of the region have inherently low soil fertility, and parts of the Yorke Peninsula and coastal plains are susceptible to wind erosion.