
James Morgan
Yesterday,
ScienceOmega.com published an interview with Dr Iain Hartley, Lecturer in Physical Geography at the University of Exeter. In the article,
Expanding Arctic forests could release more CO2, Dr Hartley explains how birch trees can act as ecosystem engineers by reducing carbon storage in soils, thus contributing to the release of carbon dioxide into the atmosphere.
This phenomenon seems contrary to common sense. One would assume that more trees would mean more plant biomass, and so more CO
2 being removed from the atmosphere. However, Dr Hartley and his colleagues found that whilst the birch trees of expanding Arctic forests in Sweden did bring with them more plant biomass, the effects of this biomass were outweighed by the trees’ capacity to stimulate the decomposition of subterranean carbon stocks.
Human beings, played here by a naughty schoolchild, are in an argument with nature, a tough and unyielding teacher. We have done wrong. We know that we have done wrong, but we want to escape the consequences of our actions.
What’s more, this phenomenon is not necessarily confined to birch trees
or to boreal Arctic regions. Birch trees appear to be particularly adept ecosystem engineers, but Dr Hartley could not rule out the possibility that other tree species might act in the same way. There is also some evidence of this process occurring at more temperate geographical locations such as parts of Scotland. Although our understanding of the phenomenon is still at an incubatory stage, it seems that large subterranean carbon stocks coupled with the expansion of a suitable tree species, could be sufficient for the loss of CO
2 to take place.
Although Dr Hartley was quick to point out that his team had collected no scientific evidence to suggest that this process would be harmful to the environment – they were simply interested in examining whether forest expansion always led to a reduction in the release of CO
2 – this does not seem to bode well for the mitigation of climate change. You might describe it as a natural, but vicious cycle. Climate change has resulted in warmer Arctic climates. Warmer Arctic climates have lead to forest expansion. Forest expansion could precipitate more CO
2 being released into our atmosphere. CO
2 is a greenhouse gas which exacerbates global warming…and so continues the circle of strife.
Of course, I am not a scientist. These are just my personal musings and I have absolutely no scientific evidence to support them. In the absence of subterranean carbon stocks, this cycle would presumably be broken and the increased plant biomass would be free to do its thang.* Even so, it seems that the only obvious answer to counteracting the effects of these pesky birch trees is to tackle climate change – and we all know how simple that is proving to be.
I don’t want to be a pessimist, but humanity seems to be like
The Fast Show’s Unlucky Alf when it comes to the environment. We mess everything up, make everything warmer, new trees start to grow and we think, ‘Every cloud…’, but before we know it, we find that these new trees are not necessarily going to reduce the net release of CO
2 in their ecosystem.**
I find it easiest to think of our battle with climate change in the following context. Human beings, played here by a naughty schoolchild, are in an argument with nature, a tough and unyielding teacher. We have done wrong. We know that we have done wrong, but we want to escape the consequences of our actions. We begin by denying responsibility,*** we then try to figure out clever ways around the problem, and eventually, we suggest that we modify our behaviour at some point in the future. Nature responds thusly: ‘Come off it’, ‘Good, but I want action now’, and, ‘When?’ Essentially, we are spoiling things for the rest of the class, but depressingly, rather than being 29 of our eight-year-old peers, ‘the class’ represents
all future life on planet Earth.
As far as I can tell, there are two options available to us. We either change our behaviour, or we carry on in the full knowledge that we were warned. If somebody were to concede that climate change is manmade, but argue that they were too rich and comfortable to change their ways, I would find it refreshing.**** At least it would be an honest response. What is the point in Dr Hartley and countless other researchers scientifically cataloguing the things that are happening to our planet, if we are simply going to ignore everything that they say? We might be able to fool one another, but nature’s having none of it.
* Thing
** Oh bugger
*** We stick with this particular tact for a ridiculous amount of time
**** Selfish, but refreshing