Critically, although restored soil showed many improvements over soil from unrestored areas, it still wasn’t as healthy as the soil profile in the intact native vegetation.
I found no such trends for invertebrates. Sometimes invertebrate health was better on the degraded site because the habitat was better suited for them, for example: pastured areas can provide better food sources for beetles as well as denser grass which suits their habitat needs.
There are very few studies that have looked at how invertebrates respond to restoration in an agricultural setting, so we need more research into this topic. My PhD on York Gum woodlands examines this in greater detail, so stay tuned for another blog later this year.
Ultimately, restoration is a long game.
My research compared 10-year old sites with 50- to 100-year-old sites and showed that even after a century, restored ecosystems showed some improvements but they don’t achieve full recovery to conditions prior to clearing. Another study has suggested it might take up to 700 years to reach the health of areas with intact native vegetation.
It’s a sobering thought that emphasises how our efforts should focus on protecting the intact bushland we have left around Australia and the world, and how important it is to support organisations like Bush Heritage.