«Staff present: Mr R Hansen (Research Director) Mr P Douglas (Principal Research Officer) Mr K Holden (Inquiry Secretary) PUBLIC HEARING—INQUIRY ...»
In the most recent figures carbon emissions from land clearing have increased to 35.8 million tonnes per year just in Queensland, so our ability to comply with our international obligations on climate protection, land degradation, biodiversity and World Heritage protection are all being compromised by Queensland’s land clearing. This bill restores many of the protections that were responsible for previously reducing land clearing in Queensland.
We are quite keen to answer your questions about our submission and about the science or any questions that may have arisen over the last few weeks. We will take on notice any questions that relate best to the expertise of members who are not present. We are aware of some confusion and misunderstanding around two particular scientific issues, and I would like my colleagues to perhaps quickly update you on those. I will turn first to Professor Catterall.
Prof. Catterall: I want to say a few things about wooded vegetation extent, which I understand has come up a bit in discussion. I will refer to the SLATS report. I presume everybody knows what that means. There is a question about whether the SLATS report shows that total wooded vegetation cover in Queensland has increased in recent years. Has it really increased?
On page 28 of the report, table 3 shows an estimated total wooded vegetation extent of
87.1 million hectares in 2011-12 and 87.6 million hectares in 2013-14. This would appear to be an increase of about 500,000 hectares of wooded vegetation. What I need to say is that scientifically this is spurious information. It does not necessarily represent any increase in the amount of wooded vegetation. The reason is that the way in which the SLATS data is obtained is through a very technical and complex process involving satellite imagery and its analysis, which is described in about 10 pages in the SLATS report in its full detail. The bottom line is that when you have some wet years you get an increase in the growth of grass and herbs and weeds as well as an increase in the foliage density of existing trees, so a little spindly tree can become a tree with lots of leaves. That gives what is essentially a false reading of increased vegetation cover. Without actually delving technically in much more detail than ever has been done into these data, it is really impossible to use the SLATS data to argue for an increase in vegetation extent.
Brisbane - 35 - 3 Jun 2016 Public Hearing—Inquiry into the Vegetation Management (Reinstatement) and Other Legislation Amendment Bill The second point is that there is of course likely to be some regrowth happening. There will be some young regrowth occurring. However, the clearing of that young regrowth is not restricted under the Vegetation Management Act or under the proposed amendments.
The third point relates to the idea of tree thickening in areas of land that are grazed. The question is has there been a recent increase in the number of trees in a sort of general sense due to vegetation thickening? There has been some research done in Central Queensland looking at that in the very long term, and that shows that when you have a series of wet years you get more trees coming into the system, but then when you have a series of drought years more trees die. Really it is just a long-term cycle of thickening and thinning that we are looking at over time. Essentially, that is irrelevant to the current act that is being discussed or its amendments. I believe the next issue will be tackled by Professor Bunn.
Prof. Bunn: One of the claims that is often made is if you clear vegetation and promote a good grass cover that is going to be beneficial in terms of reducing erosion. It is based on the observation that if people have a hill slope that has good grass cover, then that is going to yield less sediment from a run-off event than one that is bare, and that is certainly the case. But what we know is that in nearly every catchment that you look at, whether it is the Gulf of Carpentaria or from the Normanby all the way down to Brisbane, most of the sediment that gets into the channel, channel network and then out into the coastal zone comes from the channel network. Most of it is coming from channel erosion, gully erosion that is generated within that network. When I say ‘most’, in most of the catchments that we have looked at ‘most’ is greater than 90-95 per cent of the sediment load. Playing around with grass cover on hill slopes is tackling in some cases about one per cent of the sediment problem.
The problem, of course, is that when you clear vegetation you increase amount of surface run-off that gets concentrated down into the channel network and increase the power of the stream to cause erosion. That is exacerbated when the vegetation clearing goes into those gully networks and the riparian zones as well. Not only do you decrease what they call the roughness, the slowing down of water in those landscapes, but you also reduce the resistance of the ground to erosion from that event. Those two things work in unison to create a greater erosion potential. What we see then is the generation of increased channel erosion, further concentration of the flow into the channel network, deepening and widening of channels and the propagation of gullies, whether they be hill slope gullies or alluvial gullies. Certainly when you look at where the big erosion problems are across the Queensland coast, these are usually in places where those events, gullying and channel erosion, have occurred. That, of course, is a problem even right down here in South-East Queensland.
The other key thing is if we are really serious about tackling erosion and tackling the delivery of sediment and nutrients that are derived from that into our coastal zones and indeed into our water storages, then the solution to that is of course regrowing and revegetating up those sensitive areas.
That requires us to protect and restore and allow the regeneration of vegetation in those sensitive areas.
Dr Reside: I want to speak about the biodiversity aspects, particularly the biodiversity aspects of intact ecosystems. We heard this morning a query about thickening vegetation and what that means for biodiversity. The studies in Queensland’s savannah landscapes, the wooded landscapes, generally show that the thicker the vegetation the more bird species you get, the more mammals and reptiles. If you take it to the extreme, you end up with a rainforest. Rainforests are the most highly biodiverse systems we have. They are also the thickest and most densely vegetated areas that we have.
Queensland has remarkable biodiversity, as we are all well aware, and it has the highest number of endemic animals—animals found nowhere else on the planet—than any state in Australia.
Queensland’s biodiversity is just incredibly remarkable. What is also remarkable is that we do not know a lot of the species that are in Queensland. We are still describing new species every year— species not just that we think might be a bit different, but they have never been seen to science ever before and they are completely different—these are geckos and frogs and skinks and lizards—and this is happening every year. I know of several new species that have been described this year, 2016.
A lot of these in North Queensland are on Cape York in the desert uplands, and most of these that I am aware of are on private land. We have the highest number of species found nowhere else on the planet and we have one of the highest rates of discovery of new species still in 2016.
Queensland also has a lot of threatened species. We have nearly 400 threatened species in Queensland, and over 90 per cent of those are at threat from land clearing. This remarkable biodiversity is at threat from land clearing, and it occurs on private land. We need to regulate the clearing. We are not necessarily saying ‘do not clear’; we are saying we need to regulate this so we Brisbane - 36 - 3 Jun 2016 Public Hearing—Inquiry into the Vegetation Management (Reinstatement) and Other Legislation Amendment Bill protect our biodiversity. Some of the species that occur solely on private land and are vulnerable to land clearing include: the black-throated finch, a species that I have worked a fair bit on; Coxen’s fig parrot; the golden-shouldered parrot; and of course koalas, which we have heard a bit about today.
The southern black-throated finch has lost over 80 per cent of its extent, and that is all from land clearing. If any more of its habitat is cleared that species is very likely to go extinct, so we really need to look after that biodiversity and we need to regulate habitat use.
Intact ecosystems, the systems that are most likely to withstand any kind of perturbations in the system, are going to be the ecosystems most likely to withstand climate change, cyclones and they tend to be less flammable if there are more trees and less grass, so keeping ecosystems intact is really important. For species that need to shift as the climate shifts, they need to have that habitat so that they can do that. Intact ecosystems are absolutely the most important that we need to protect, but high-value regrowth is also really important and also supports a lot of species, endemic species and threatened species.
I just want to quickly touch on the fact that Queensland’s biodiversity has a lot of economic opportunities but most of which is unrealised. Believe it or not, there are a lot of people in the world who really like birdwatching and pay a lot of money to come to Queensland to see Queensland’s birds, and they are going to need to go to intact landscapes to see most of those bird species. It is a huge tourism opportunity and it happens elsewhere in the world. Queensland’s biodiversity is economically important for carbon farming opportunities, ecosystem regulation and many other things. Reinstating this bill is really important for saving Queensland’s biodiversity.
Prof. Possingham: My colleagues have covered much of what I would like to say, so I will just underline a couple of points. The first one, I suppose, is do not underestimate your environmental scientists. There are three global ranking schemes, and remarkably the University of Queensland is ranked fifth, 10th and 12th in the entire planet in environmental science. There are over 10,000 universities in the world, and we are ranked fifth, 10th and 12th ahead of places like Yale, Oxford and
Cambridge. The only two centres of excellence in the environment in Australia are in Queensland:
one hosted at UQ and one hosted at James Cook University, so by any measure this is the best and highest concentration of conservation biologists and environmental scientists basically on the entire planet. We have visitors from all over the world seeking advice. Some of the expertise is very relevant, for example, to the recent discussion from Jen from the Property Council of Australia, strategic assessment work and offsetting work. Martine is probably the world expert on world biodiversity offsets. We have worked for 10 years with the federal government and state governments on strategic assessments. Strategic assessments are almost certainly the way to go for South-East Queensland if you really want to have koalas here for the next 20 years, so I agree entirely with what Jen said.
There is an enormous depth of talent and breadth, and the science we do is highly multidisciplinary.
We are economists, an honours mathematician, hydrologists and we are water scientists. We are not just a whole heap of ecologists; we are very diverse.
I would just to underline a couple of things. It is a fact that extinction rates are 100 to 1,000 times the background rate. Triple-bottom-line sustainable eco-systems would mean that ultimately everything should be stable—the economy, social issues and the environment—and they should all be going flat or up. That is what I consider to be triple-bottom-line accounting. At the moment we are losing on the biodiversity side. The fact is that we are losing species at 100 to 1,000 times the normal historical rates.
I will finish by saying that I consider in some senses—and this may surprise you—land clearing is a big threat to rural communities and a big threat to agricultural profitability. A month ago I was in China and I met the richest man in mainland China, Jack Ma, and his colleagues who are very interested in the environment. They have formed a land trust and they are doing a lot of conservation.
In that conversation with those people—wealthy and important people in China—they talked about food all the time. They talked about clean food, which you know all about, and they talked about sustainable clean food. I am very, very worried that many of our buyers will be saying, ‘We just don’t want clean food,’ which I know we can produce and the Chinese love. They want to know that the food we produce is being done in a sustainable way and that it does not cause extinction, does not cause increased threats to the Great Barrier Reef and all the things in these documents. I think we need to think about that from an economic and social side as well.
CHAIR: Thank you very much for your statements; they are very informative. My first question is about the regeneration and repair of land, particularly in riparian areas. I note your comment, Professor Bunn. You say we need to look after those areas, and doing that is to ensure that they are locked in as riparian areas. How do the people who own land within these areas manage it, particularly Brisbane - 37 - 3 Jun 2016 Public Hearing—Inquiry into the Vegetation Management (Reinstatement) and Other Legislation Amendment Bill with the really bad weeds that generate 10 to one to any other plant and strangle the trees and kill them? The question is if we lock these areas away and the farmers do not look after them, who is going to do it?
Prof. Bunn: I guess it comes down to the issue of whether we are locking it away or we are managing it. I think the key thing to riparian management, and certainly all the guidelines that were developed 20 years ago in the national riparian program that was undertaken, is the recognition that these are important parts of the landscape that need to be managed differently.