Is there really less pasture under the tree? Using an Active Optical Sensor (AOS) to measure changes in pasture around trees in grazing landscapes

Abstract

Scattered trees are a valuable natural resource, for both above- and below-ground services. However, it has been estimated that within 40 to 185 years, these trees could be lost from the landscape. Without these trees there will be many environmental and agricultural consequences, as is evident by the current degradation in landscapes from where they have already disappeared. With the continual decline of scattered trees across Australia it is a critical national issue to determine the most advantageous way to sustain them in grazed pastures, in ways that contribute to both agricultural production and environmental enhancement. To date many of these functional attributes have not been examined and consequently stakeholders are unable to make informed decisions about the positive and negative effects of incorporating native vegetation in pasture landscapes. This research aims to fill these knowledge gaps for the grazing industries on the Northern Tablelands of NSW, helping landholders improve production and profitability in the changing climate of the 21st century. The specific aim of this investigation was to determine how native eucalypt species on different soil types altered pasture biomass around them, as pasture productivity and quality is the single most important attribute for graziers, as it drives the level of attainable production.