Wildflower and native grasses role in revegetation
Murdoch University researchers have identified that wildflowers and native grasses may be the missing element to achieve success in revegetation of northern wheatbelt sites once used for cropping and grazing.
Such areas are often difficult to restore due to the extensive modification of soil properties and vegetation communities following cultivation, resulting in the degradation of these key ecosystem components.
Results from a study led by PhD candidate, Tina Parkhurst , from the Centre for Terrestrial Ecosystem Science and Sustainability at the university’s Harry Butler Institute found herbaceous plants – those without a woody stem – were the missing component.
“Ecological restoration is extremely important for maintaining our biodiversity, especially the unique species we have here in Western Australia,” Ms Parkhurst said.
“However, our research has shown that sites of unproductive agricultural land aren’t recovering to their native eucalypt woodlands and woody shrublands in semi-arid Western Australia, even ten years after restoration.
“Major barriers to restoration are elevated soil nutrients and limited native seed availability due to undeveloped soil seed banks, limited seed dispersal, and seed and seedling predation from ants and agricultural pests.
“Most revegetation projects focus on planting mid- and overstorey vegetation such as trees and shrubs, which increases native plant diversity,” Ms Parkhurst said, “but they’re missing the smaller, yet significant components of these ecosystems like everlastings, native herbs and grasses.”
“To date very few restoration projects have attempted to include native everlastings and other annuals in standard revegetation methods, but we are hoping to change this in the near future.”
The next phase of the research will see the development and testing of revegetation methods that include herbaceous species to see if abandoned agricultural land can bereturned to its original, species rich and resilient woodland state.