Landscape scale survey of indicators of soil health in grazing systems

In a broad-scale survey across pasture-based grazing systems in south-eastern Victoria, soil biological and chemical properties were measured in an effort to establish baseline levels for commonly used indicators of soil health. Although soil properties were highly variable among sites and biological properties were difficult to predict, total soil C was found to be closely associated with soil cation exchange capacity (CEC). Importantly, the strength and nature of relationships between soil properties differed among soil textural classes. We also measured a range of soil and vegetation properties in a small number of patches of remnant vegetation and their adjacent grazed pastures. This was done in an effort to assess the sensitivity of these measures when used on samples collected from strongly contrasting land-use types. Although some factors, such as mycorrhizal colonisation of roots and soil C, did differ between the two land-use types, other factors measured in this study did not. Together, the findings of this survey provide baseline information on the landscape scale for commonly used indicators of soil health. The study explores relationships between these soil properties and assesses how they differ between two strongly contrasting land-use types. The results are discussed in the context of monitoring soil and vegetation attributes relevant to soil health.