ConservationBytes.com

I’ve had a busy weekend entertaining visiting colleagues and participating in WOMADelaide‘s first-ever ‘The Planet Talks‘. If you haven’t heard of WOMADelaide, you’re truly missing out in one of the best music festivals going (and this is from a decidedly non-festival-going sort). Planet Talks this year was a bit of an experiment after the only partially successful Earth Station festival held last year (it was well-attended, but apparently wasn’t as financially successful as they had hoped). So this year they mixed a bit of science with a bit of music – hence ‘Planet Talks’. Paul Ehrlich was one of the star attractions, and I had the honour of going onstage with him yesterday to discuss a little bit about human population growth and sustainability. It was also great to see Robyn Williams again. All the Talks were packed out – indeed, I was surprised they were so popular, especially in the 39-degree heat. Rob Brookman, WOMADelaide’s founder and principal organiser, told me afterward that they’d definitely be doing it again.

But my post really isn’t about WOMADelaide or The Planet Talks (even though I got the bonus of meeting one of my favourite latin bands, Novalima, creators of one of my favourite songs). It’s instead about a paper I heralded last year that’s finally been accepted.

In early 2012 at the Terrestrial Ecosystem Research Network (TERN) symposium in Adelaide, the Australian Centre for Ecological Analysis and Synthesis (ACEAS) put on what they called the ‘Grand Challenges’ workshop. I really didn’t get the joke at the time, but apparently the ‘grand challenge’ was locking 30 scientists with completely different backgrounds in a room for two days to see if they could do anything other than argue and bullshit. Well, we rose to that challenge and produced something that I think is rather useful.

I therefore proudly introduce the paper entitled Brave new green world: consequences of a carbon economy for the conservation of Australian biodiversity just accepted in Biological Conservation. The online version isn’t quite ready yet (should be in the next few weeks), but you are welcome to request a preprint from me now. If you attended (the surprisingly excellent) TERN symposium in Canberra last month, you might have seen me give a brief synopsis of our results.

The paper is a rather  in-depth review of how we, 30 fire, animal, plant, soil, landscape, agricultural and freshwater biologists, believe Australia’s new carbon-influenced economy (i.e., carbon price) will impact the country’s biodiversity.

Before I summarise the main themes, a little background is warranted. Most people have heard of the Kyoto Protocol established in 1997 that set binding targets to reduce greenhouse gas (GHG) emissions by 5 % (2008-2012) relative to 1990 (first commitment period) for signatory countries. Most might know too that Australia was a non-signatory until 2007 when Kevin Rudd famously allowed climate change into Australian politics. Kyoto has just entered the second commitment period (2013-2020) to which Australia has also signed-up.

The Kyoto Protocol has three main GHG emissions-reduction mechanisms:

1. emissions trading (i.e., the carbon market);
2. a Clean Development Mechanism (which aims to reduce emissions in developing nations); and
3. joint implementation (specific agreements between countries)

The first commitment period didn’t allow forest management to be included in emissions-reductions mechanisms, but the second now does. However, there are many other activities that are not covered under Protocol that need to be considered for effective emissions reductions.

Enter Australia’s 2011 Carbon Farming Initiative (CFI), which is a financial incentive to land managers and farmers to reduce GHG emissions from business-as-usual activities or to sequester (store) carbon on (or in) the land – this is known as an ‘offset scheme’. How is this funded? Well, the country’s biggest industrial emitters of GHG now have to buy Australian Carbon Credit Units (ACCU) for AU$23 per tonne of carbon dioxide equivalents (CO2-e) emitted. This is otherwise known as a ‘carbon price’, or quite unfortunately for political reasons, a ‘carbon tax’.

As much as I disagree with letting the market set the price, the ACCU is destined to rise 2.5 % per year until 2014/2015, after which it will be set by the market.

From a landscape and biodiversity perspective, the CFI includes the following mechanisms for emissions reductions:

• agricultural,
• introduced animal and
• legacy landfill emissions

It also has what are known as ‘sequestration offsets’. These are:

• sequestering carbon in plants as they grow,
• increasing soil organic matter,
• avoided vegetation loss,
• afforestation,
• reforestation,
• revegetation,
• rangeland restoration and
• native forest protection

All mechanisms must be additional, have no leakage, and be ‘permanent’ as defined under current Australian legislation (a horrible set of minimum standards that we’ve previously called the ‘unholy trinity‘). If you want more detail on the CFI, visit the official website here.

Ok, enough of the boring legislation stuff. On to the biodiversity. We broke down our assessment into 6 themes where we believed the CFI would have the greatest impact on Australian biodiversity:

1. Environmental plantings
2. Policies and practices to deal with native regrowth
3. Fire management
4. Forestry management
5. Agricultural practices (including cropping and grazing)
6. Feral animal control

1. Environmental Plantings

I’ve discussed before how about 40 % of Australia’s forests have been destroyed since European colonisation, and how much of our remaining forest cover is highly fragmented. As such, any investment that encourages tree planting is largely a good thing if it leads to increasing native forest cover. This is in fact where the largest biodiversity bang for our carbon buck will come, but there are some potentially frightening ‘bioperversities’ as well. For example, we need to be careful not to plant just the fast-growing, simplest and (universe forbid) non-native plantation species only to ‘farm’ carbon. If we’re clever and plant with ecological restoration in mind as we go, we should be able to avoid the worst of these possible bioperversities. Second, planting trees often changes the landscape’s hydrology, which could inadvertently lead to drying out in some places, more fires, and perversely, more carbon released.

2. Native Regrowth

Most broad-scale clearing in Australia now illegal, so regrowth vegetation in once-cleared areas is a substantial element of Australia’s future biomass carbon. As such, we need to manage this regrowth optimally, by which we mean the action of keeping (not clearing) existing, human-modifed vegetation, or avoiding cropping/continuous grazing. Interestingly, vegetation retention under Australian legislation defaults to regrowth, and most young regrowth can be legally re-cleared for agriculture. Thus, if we can encourage ecologically healthy regrowth, we can get a large carbon-sequestration and biodiversity benefit simultaneously. The problem is that regrowth management legislation differs among the states, thus seriously impeding the implementation of an efficient national management system. For example, in some states like NSW and Queensland, native regrowth in over-cleared landscapes might already be protected for biodiversity as the only remaining habitat, whereas some regrowth can be declared ‘invasive native species’ in NSW, and so may be replaced with more productive vegetation cover, or re-cleared for agriculture. Some states even prevent thinning of dense regrowth, which seriously hampers its capacity to sequester carbon and become suitable habitat for native species.

3. Fire

In a dry country whose vegetation dynamics are largely driven by moisture gradients and fire, fire management is a big player in the Australian carbon game. By applying fire at the right time, one  can potentially increase carbon storage indirectly and abate non-GHG emissions via the reduction in intensity and frequency of  high-intensity fires, thus minimising the total fuel burnt. This is already happening in the Northern Territory where clever fire management has already prevented  the emissions of 100,000 t CO2-e (non-CO2 GHG only) per year over the last few years. However, such approaches are unlikely to work in southern Australia because of the completely different fire dynamics and human complications involved.

4. Forestry

Australia is currently undergoing an historic transition from old-growth forest to plantation harvests, and the once-common practice of using fire to remove logging debris is now much less attractive under the new carbon economy. Perhaps the most-touted capacity to retain more carbon in forests subject to harvest is by increasing rotation times, which would also benefit wildlife; however, modifying rotation times is currently not covered under the CFI. Another problem is leakage – if we reduce overall wood supply from Australian forests, is the demand for timber just going to be supplied from other countries (thus negating the net carbon benefit)? The problem here is that Australia has very poor forestry ‘life cycle’ data with which to estimate its carbon budget and avoid leakage.

5. Agriculture

About 60 % of Australia is devoted to cropping and grazing, so if we can manage to modify agricultural practices using carbon legislation that also benefits biodiversity, the potential gains are large. Probably the main things that will happen under the CFI is encouraging a reduction in nitrogenous fertilisers that contribute NOx directly to GHG emissions, and indirectly via their manufacture and transport. The addition of biochar to the soil to increase carbon retention is another, but these last two modifications are unlikely to bring many biodiversity benefits to agricultural land.  Other changes include reducing the frequency of tillage and replacing annual crops with perennials – again, the biodiversity benefits here are likely to be marginal. The final two likely outcomes for agriculture – increasing the retention and encouraging the regrowth of shrubs, and reducing grazing pressure, are the most likely to have any real biodiversity benefits. If we ever manage to get off the cow and sheep fix and farm kangaroos instead, our overall methane reductions would be substantial, and the benefits to the rangelands overwhelming. Will this ever happen? Probably not in my lifetime.

6. Feral Animals

Top panel: Estimated number of cattle, sheep, kangaroos and feral herbivores in Australia; Bottom panel: total emissions per group per year (carbon dioxide equivalents)

Finally, there have been a few proposals to reduce feral animals under carbon-reduction legislation. While it’s definitely a good idea to get rid of Australia’s incredibly menagerie of invasive herbivores (some 13.5 million pigs, > 1 million camels, 2.6 million goats, 200 million rabbits, 0.2 million deer, and 0.35 million swamp buffalo), the simple fact that most of Australia’s animal methane production comes from the > 20 million cattle and ~ 70 million sheep grazing our rangelands. When translated into carbon dioxide equivalents, all feral herbivores combined contribute only about 5 % of all the methane produced from sheep and cattle. The carbon emissions that would result from the efforts to kill ferals (e.g., helicopters, vehicles, etc.) means that substantial feral animal density reductions financed under the CFI are unlikely. Shame, really.

In conclusion, we predict that most landscape changes resulting from the CFI are likely to be compatible with biodiversity maintenance and enhancement, with the largest potential GHG mitigation using ecological principles achieved by enhancing woody biomass. There are, however, many potential negative biodiversity outcomes if land management is not done with biodiversity in mind from the outset. Of course, we cannot yet predict some of the synergies or economic trade-offs that might shift outcomes, and future carbon prices will be highly influential on optimal land-use decisions over the coming decades.

We also encourage conservation planners to start taking GHG-abatement values into account when planning ‘optimal’ biodiversity outcomes, and we need to develop much more transparent, standardised and easily monitored biodiversity metrics across entire landscapes if we are to get biodiversity the same consideration as carbon values. In general then, we’re cautiously optimistic (unless future governments idiotically kill the carbon price system).

CJA Bradshaw

P.S. I should also mention my fantastic co-authors:

David M. J. S. Bowman, Nick R. Bond, Brett P. Murphy, Andrew D. Moore, Damien A. Fordham, Richard Thackway, Michael J. Lawes, Hamish McCallum, Stephen D. Gregory, Ram C. Dalal, Matthias M. Boer, A. Jasmyn J. Lynch, Ross A. Bradstock, Barry W. Brook, Beverley K. Henry, Leigh P. Hunt, Diana O. Fisher, David Hunter, Christopher N. Johnson, David A. Keith, Edward C. Lefroy, Trent D. Penman, Wayne Meyer, James R. Thomson, Craig M. Thornton, Jeremy VanDerWal, Dick Williams, Lucy Keniger and Alison Specht