Farm revegetation has substantial potential to improve biodiversity outcomes.

Abstract

Agricultural expansion and intensification has caused habitat loss, contributing to the current biodiversity crisis. Reliable, efficient and consistent information at the farm-scale is critical to understand the magnitude of recent changes in biodiversity and to inform future management actions aimed at reversing historical declines. We apply a habitat-based biodiversity assessment approach to examine the potential for grazing farms across Australia to improve outcomes for biodiversity by revegetating 10 % of the farm area. Fourteen case-study farms distributed across Australia with diverse attributes were assessed, including an analysis of likely benefits for biodiversity 30 years after commencing a hypothetical revegetation scenario, within the context of estimates of recent historical changes. From 2004 to 2020, the three biodiversity indicators considered decreased for the majority of farms. The scenario for revegetating 10 % of the farm area was estimated to substantially increase the biodiversity indicators, with half of the farms estimated to achieve recovery for all 3 indicators to greater than 2004 levels by 2050. Smaller farms with lower average ecosystem condition in 2020 were estimated to achieve the greatest gains in biodiversity from the revegetation scenario, relative to their indicator values in 2020. Farm revegetation actions have substantial potential to improve outcomes for biodiversity, though such gains may be difficult and time consuming to achieve, emphasising the importance of avoiding further habitat loss through removal or degradation of native vegetation.