Intact ecosystems the best buffer against climate change
How can we adapt to climate change? Seed the clouds to encourage rain in drought-ridden areas? Sow iron in our oceans to increase carbon dioxide uptake? Mine comets for water? While these high-tech solutions might capture the imagination, two Australian researchers are arguing that we might be missing the obvious solutions that already lie under our noses; simply invest in first protecting, and if this is not possible, then restoring our natural ecosystems, and they will do the same for us in the face of a changing climate.
“We’re getting further and further away from what is really one of the key issues, which is how do we maintain intact functioning ecosystems on land and sea,” says Dr Tara Martin, Principal Research Scientist at CSIRO Land and Water. “Often people think to deal with climate change we need some new revolutionary actions or outrageous technological fixes when we just need to look after our forests, our wetlands, our seagrass beds, our mangroves.”
Natural ecosystems such as coral reefs can reduce the impact of sea level rise by providing storm protection, reducing wave energy by an average of 97%. Yet in some parts of the world, such as Melanesia, coral reefs are being pulled apart and used to build seawalls to serve the same function but far less effectively and cheaply.
The loss of that coral reef also means the loss of an extremely protein-rich ecosystem that could feed coastal communities, and such a loss is not reversible; once those reefs are gone, they cannot be restored.
There is also growing evidence that intact forests impact climate at a local and global level, says Associate Professor James Watson, principal research scientist at the University of Queensland’s School of Geography, Planning, and Environmental Management, and Director of Science and Research at the Wildlife Conservation Society.
“Intact forests not only are incredibly important for carbon sequestration and storage, there is now considerable evidence they influence both planetary and local weather regimes as well,” Watson says.
For example, research across Australia and around shows that as forest becomes cleared, degraded and fragmented, there is a greater chance of drought occurring in that area. Intact forests also help protect humans from storms and extreme weather events, so cutting down those forests not only negatively impacts the carbon cycle and the weather, but reduces the ability of local communities to adapt.
“One that stands out is during the drought in western Queensland, we allowed cattle into endangered, but still intact, woodland habitat to feed on the vegetation inside these areas,” Watson says.
“These areas have now become more degraded which means there is likely to be more drought as a consequence of that; it’s bad short-term policy which is going to cause long-term harm to the very farmers who are doing it.”
Carbon sequestration by intact ecosystems offers a huge opportunity to mitigate climate change, while having the additional benefit of preserving natural buffers against climate change. Martin says Australia has a very good understanding of the potential of different ecosystems to sequester and store carbon; we just need to act on it.
“We know which areas across Australia are most important for those carbon reserves, and we also can combine that with information on biodiversity so that if we can tackle both in tandem—conserve high biodiversity areas that are rich in carbon storage—then we’re getting twice the bang for our buck,” she says.
This could be applied particularly in areas where traditional farming is struggling, and will likely only struggle more as a changing climate further reduces rainfall and increases temperatures.
Martin suggests that instead of farmers being allowed to graze on conservation lands, and risk degrading those lands, they could be paid instead to be custodians of the ecosystem service provided by those intact systems.
“Instead of paying them to produce livestock on marginal land, pay them to maintain healthy ecosystems that can produce clean water, clean soil, and sequester carbon,” she says.
This could apply to northern regions of Australia currently being considered as a potential new food bowl for Australia. Watson says opening these up for more agriculture could do more harm than good.
“That is the largest intact savannah on Earth, with serious carbon stores and which plays a major role not just in terms of local climate regimes but also planetary scale climate regimes,” he says. “If we go and open it up and start eroding it, not only will the current farming situation in the north deteriorate but in the long term we will likely be creating far more harm than good.”
Awareness of the value of ecosystem services, such as the provision of clean water, clear air, food, and shelter, is growing around the world. A 2005 report by the World Bank valued services at around US$33 trillion globally. But Martin says we need a big shift in thinking to change our course away from high-tech, fossil fuel-based solutions.
“It’s not that we don’t need technology—we absolutely do and technology will really deliver some of these amazing adaptation strategies—but we need to get back to basics and recognise that our human wellbeing really depends on the planet’s wellbeing and that means looking after these essential ecosystem services that nature provides.”
Nature Climate Change paper: Intact ecosystems provide best defence against climate change
Article in The Conversation: The best way to protect us from climate change? Save our ecosystems