Fate of native plants could depend on individual landholders
THE FATE of entire plant species endemic to the Gladstone region may be dependent on individual landholders, according to University of Queensland associate professor Dr Rod Fensham.
In December Dr Fensham authored an Australian Journal of Botany report identifying priority regions and threats for threatened plants in Australia, including six species in the Gladstone region.
These were the narrow-leaved malletwood (rhodamnia angustifolia), oldenlandia herb (oldenlandia gibsonii), cossinia (cossinia australiana), Yarwun whitewood (atalaya collina), apatophyllum olsenii and bulberin nut tree (macadamia jansenii).
Dr Fensham said the plants existed in small populations within and close to the Gladstone region.
"For some reason that we probably can't explain very well, in your part of the world around Gladstone there's a bunch of species that just locally occur,” Dr Fensham said.
"It's probably something to do with a long-term history of past climates and environments that allowed these species to either evolve there or survive there.”
He said while some including the apatophyllum olsenii and the bulberin nut tree were in protected areas, the atalaya collina was "only known from one property”.
"Its extinction or survival is totally dependent on one or two landholders,” Dr Fensham said.
He said the plants existed in "dry rainforest” environments, which often had threatened species due to high plant biodiversity "in coincidence with intensive land use”.
"While it doesn't rain all that much around Gladstone, you still have these fire-protected ecosystems that retard fire,” Dr Fensham said.
"The rainforests are tiny little pockets and the fires burn the surrounding eucalypt forests and tend to stop at the edge of the rainforests.”
He said the main threats to the endangered species included extensive clearing of land, fires, inbreeding and the "extremely common” lantana weed.
"Lantana is resisted by the shade but if you can open rainforests up with fire or cyclones it can get in,” Dr Fensham said.
"The lantana has made these fire-retardant rainforests flammable because it creates this layer of fuel near the ground.”
He said it was hard to identify what impact an extinction would have on humans and the region's ecosystems.
"You can kind of look at it from a human-centric view point and go 'what is humanity going to lose if these things go extinct?',” Dr Fensham said.
"The macadamia jansenii may well have genetic information that can be used for breeding a better macadamia nut.
"The other thing that can happen is there's a network of food webs between individual species ... and if you lose parts of that network there are good examples around the world where the whole network has collapsed.
"But for me it's more just a philosophical and spiritual responsibility of humanity to look after biodiversity.
"Species evolve over millions of years and that depth of time is pretty profound and something we should look after.”