The push for tougher tree-clearing laws in Queensland is not supported by evidence, according to one of the State’s most experienced and longest serving Government ecologists.
Dr Bill Burrows is a former senior principal scientist with the Queensland Department of Primary Industries (now Department of Agriculture) and served the State Government for more than 40 years.
Now retired, he has spoken out against the Queensland Government’s stated plans to reintroduce stricter controls on the clearing of trees, shrubs and woody regrowth on rural land.
Dr Burrows says the science does not support claims that tree clearing on rural properties poses a significant threat to above-ground biomass in the State.
Satellite and on-ground data shows that woody vegetation in Queensland is in fact increasing, he said, and reintroducing strict restraints on clearing trees and shrubs will achieve little more than threaten the viability of many rural enterprises.
Dr Burrows said satellite based sensors can now reliably detect changes in the above ground biomass of vegetation, as well as carbon dioxide levels in the air column above the earth’s land mass and oceans.
Contrary to claims suggesting tree clearing has rampantly diminished the State’s tree coverage, Dr Burrows said satellite data shows that above-ground biomass increased in Queensland over a 20 year observation period from 1993-2012.
This occurred even though the same period included different years of well below or well above average rainfall, along with the period of extensive so-called panic clearing that occurred in the highly publicized lead-up to the passing of the State’s Vegetation Management Act in 1999.
The satellite sensor observations are further validated by a myriad of ground-based and aerial-photo interpretation studies, Dr Burrows said.
“This research confirms that uncleared woody vegetation is “thickening” (increasing in stem density, stem size/basal area and/or canopy cover) on the State’s rural landholdings.
“This results in increased woody plant biomass and carbon storage, as well as providing strong competition that limits the growth of associated pasture.”
A “net sink” for CO2
Dr Burrows says independent sensors on Japanese and US owned satellites also now show that Queensland is a net annual sink for Carbon Dioxide.
“In other words, vegetation is currently removing more Carbon Dioxide from the air above this state than is being added to it from the combined impacts of land clearing, plant respiration, fire, fossil fuel use, adjacent ocean outgassing etc.”
Those who proposed the reimposition of strict tree clearing bans on agricultural holdings did so with scant regard for vegetation history, the welfare of rural landholders, sustainable management of rural resources and many desirable conservation outcomes, he said.
A more in-depth summary of Dr Burrow’s position on proposals to increase tree clearing controls in Queensland can be viewed by clicking here.