The Northern and Yorke region’s soil is a critical asset to agricultural productivity and natural biodiversity. The characteristics of soil are one of the key factors that determine where different crops may be grown and the natural distribution of native plant species. The soil also provides habitat for a range of plants and animals: burrowing mammals, marsupials and reptiles, invertebrates and microbial organisms.
The Northern and Yorke region is made up of three major landforms:
- Yorke Peninsula – a plain of 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 soil degradation issues.
- Coastal plain – shallow calcrete and calcareous loams with some areas of dune-swale and sand. Wind erosion and saline soils are the main issues.
- Northern Mount Lofty Ranges and Southern Flinders Ranges – neutral loamy soils over red clay subsoils. Water erosion, dryland salinity and soil acidification are the main issues.
The importance of soil
Soil is important because it:
- is one of the primary features that determine vegetation types and land suitability for primary production uses
- is home to fungi, bacteria, burrowing animals, invertebrates and other animals that provide ecosystem services, such as recycling nutrients and binding soil particles
- has physical, biological and chemical properties that affect the moisture, nutrient and biota levels on which plants depend.
Causes of soil degradation
Soil degradation can be caused by:
- clearance of vegetation
- disturbance by cultivation for the sowing of crops and pastures
- soil disturbance for weed control
- stubble removal practices such as burning
- over-grazing by domestic stock
- crop failure or poor growth
- grazing, burrowing and hoof impacts of pest animals such as rabbits, deer and goats
- use of the land that causes inadequate protection.
Results of soil degradation
Degradation of soil can result in:
- reduced soil fertility
- poor plant establishment
- reduced productivity of crops and pastures
- loss of native plant species that cannot grow under altered conditions
- susceptibility to invasion by weeds tolerant of degraded soils
- increased recharge of groundwater
- increased acidification of soils
- increased dryland salinity
- susceptibility to erosion by wind and water
- wind erosion can smother plants and seed reserves
- wind erosion can be a health hazard to people, causing breathing difficulties and reducing visibility for traffic
- water erosion can lead to soil deposition in creeks, rivers and the marine environment which can smother aquatic plants and life forms and alter the hydrology.
Managing soil health
Healthy management of soils involves:
- managing the risk of wind and water erosion through sustainable management practices, particularly the occurrence, intensity and timing of tilling and the quantity and nature of surface cover
- managing the impact of water erosion through contour banking and flood control dams
- managing soil acidification through the application of lime
- modern agricultural weed management practices that are selective and integrated.
How we can help
Information is available on soil management, including:
- Healthy soils
- Land class
- Contour banking
- Direct seeding
- Protecting soils
- Managing soil acidity
- Liming acid soils
- Dry land salinity
- Soils in the region
- Clay spreading on sandy soils
- Delving sandy soils
- Clay spreading report
- Soil Smart Booklet
- Soil carbon and your farm - Yorke Peninsula
For more information, contact us.