Measurement of biological diversity of arthropods and respiration in soils managed under time-controlled and set-stocked grazing practices in central-west New South Wales, Australia

In this study we compare the effects of two contrasting grazing regimes (time-controlled grazing (TCG) vs set-stocked grazing (SSG)) on selected parameters of soil biological health. The purpose of the study was to evaluate these soil parameters as potential indicators of soil health and thence sustainable soil management. Two parameters, viz., arthropod biological diversity and soil respiration were chosen as reliable indicators of soil health. Samples of pasture cover, arthropod populations, and soil from varied depths were obtained in spring (September-November 2010) and autumn (March-May 2011). Results from the autumn showed a strong effect of time-controlled grazing with increased arthropod abundance and enhanced soil biological respiration while in spring the differences were not significant. It was concluded that a change to short-duration rotational grazing can be beneficial to soil biological health in the longer term and that the measurement of arthropods present in the litter and topsoil can be a simple yet effective indicator of the impact of grazing regime on soil health.