Space: the final frontier. This year marks
the 50th anniversary of the Apollo 11 moon landing mission; the
first time we had ever stepped foot on the moon. As Neil Armstrong boldly
declared “that’s one small step for man, one giant leap for mankind”, we
perhaps reached a new peak of human achievement. A peak that continues to climb
upwards, itself shooting for the moon.
I’ve grown up with franchises like Star Wars and Star Trek. Where somehow there’s always a white (human) man getting into trouble with aliens and flying space ships. One thing that’s common in much science fiction is the idea that we can colonise new worlds, terraforming their surfaces to sustain life (as we know it). This idea is pervasive in the years since the moon landing, and continues to be drawn upon even in recent films claimed to be scientifically sound (e.g. Interstellar and The Martian). Whilst this is a romantic idea—of humans gallivanting across the galaxy (hitchhiking even)—I sometimes worry about the price of this dream. Of course, I’m sure the notion has inspired many great minds the world over to learn about space, and perhaps to successfully take us all there one day. But does this idealism come with a cost?
During my first week in Dublin, Ireland, I was more shocked by the countless sunny-rainy shifts within one single day than its natural beauty, although I had been warned of its fickle weather in advance. That was something totally new to me. Born and raised in a small inland town in North China, I had grown accustomed to taking for granted that a whole sunny day could be prophesised by bright morning sunlight through the window. Then I started to imagine that, if fitting a curve to the weather, the curve of my birth village would surely be much smoother than Dublin, even though the former has four much more distinct seasons. But, at that moment, I had neither realized that this thought actually reflected the difference in the temporal autocorrelation of environmental conditions in the two places nor how this could be linked to the dynamics and stability of ecosystems.
Last week, the Zoology department hosted the first Irish One Health workshop, welcoming speakers and attendees from a range of disciplines. This gathering provided an opportunity to discuss the One Health initiative, which aims to solve world health problems through transdisciplinary collaboration, through a series of short presentations discussing various aspects of global health, and ample time for discussion between attendees, including representatives from the DAFM, EPA, HSE and AFBI.
Our own Dr Peter Stuart, who organised this workshop, gave a fascinating introduction to the concept of One Health, using the example of Hookworm in the American South during the 20th century as proof that we need to work collaboratively to solve current health issues.
The debate on what is better for the environment and by extension many ecosystem services, high intensity conventional farming using large amounts of fertiliser and pesticides on mostly homogenous areas or low intensity possibly organic farming in a heterogeneous landscape seems to be a no-brainer. High intensity farms are pressing into natural habitats, pesticides are impacting pollinators and natural pest controls such as beetles or spiders (Hole et al., 2005, Biological Conservation) and the overuse of fertilisers are contaminating ground and surface water leading to eutrophication and even drinking water pollution.
However, on a larger scale this question seems to be more difficult to answer. The problem is that in theory, and most of the recent scientific literature supports the hypothesis that the product yield of organic farming is lower by 5 to 34 % (e.g. De Ponti et al., 2012, Agricultural Systems; Seifert et al., 2012, Nature). In return, to maintain the production levels, more land has to be devoted to agriculture, potentially destroying natural habitat. This leaves the following question: On a landscape scale, what is environmentally better, a large area of organic farming with a decent environmental footprint, or a mosaic of intensive farming and high quality natural habitat?
This debate is still ongoing and far from concluded. In their paper Grau et al. (2013, Current Opinion in Environmental Sustainability) showed that current research is still conflicting, especially since results vary quite a bit when looking at different taxa in different landscapes. On one side sparing supporters point out that in addition to the already mentioned higher land-availability, the higher yield will potentially reduce the per yield impact of farming (e.g. the greenhouse gas emissions per ton grain harvested).
On the other side supporters of sharing point out, that apart from the already mentioned effects of intensive farming on ecosystem services, there should at least be a bold question mark added to the statement that increasing yield will actually lead to land being made available for natural habitat. Land might become available for urban sprawl instead, especially in times of high property prices people might be drawn into a more rural/suburban setting, or the land may not leave agriculture at all but rather be used of agricultural expansion.
So what is the better solution? We don’t know yet. The most likely answer is neither. The best strategy will be dependent on factors on all spatial scales, from disturbance resistance of present taxa, to environmental conditions such as climate and soil type up to socio-economic issues such as land planning. Still the debate has been most beneficial to science. It has sparked multiple excellent large scale research projects that boosted the understanding of landscape scale impacts of farming on ecosystem services, and how regional-scale agricultural management can best benefit ecosystem services and by default ourselves.
Anti-environmentalists and apathists often ask why bother to conserve nature – what does it do for us? Cue enthusiastic green arm-waving and heavy sighs from environmental scientists and ecologists who have faced this attitude their entire careers.
Nature is undeniably important for the human race – we wouldn’t be here without plants fixing the sun’s energy into carbohydrates and producing oxygen as a by-product, we wouldn’t be able to grow any food to eat without the myriad of organisms which create and maintain the soil, and exposure to nature has numerous psychological and physical benefits for our health. And yet, it is not valued in political decision-making. The environment, particularly the living biological part of it, is a “cross-cutting” issue which means it’s ignored by most government departments, including those that should be valuing it the most (e.g. Department of the Environment, Community and Local Government; Department of Agriculture Food and the Marine; Department of Communications, Energy and Natural Resources). This is because most decision-making is driving by economics.
International momentum has been building for governments, businesses and organisations to begin valuing nature. This doesn’t just mean putting a price on nature – it’s not all about price-tags – but valuing natural capital in the same way that any other capital (financial, human, built etc.) would be valued. And accounting for this capital in decision-making processes at all levels (from individuals up to government policy).
Some countries and individual corporations have made good progress with this (e.g. the UK has a Natural Capital Committee, Coca-Cola and Puma have famously adopted Natural Capital Accounting systems), but there has been little progress in Ireland, until now.
In April, the first Natural Capital Ireland Conference was held, which brought together academics, government representatives from national and local levels, government organisations, NGOs, business and finance and other stakeholders. The point of the meeting was to try and increase understanding of valuing nature nationally, and progress natural capital accounting at all levels.
Whether this will bump the natural environment up the political agenda, and increase people’s interest and enthusiasm for nature remains to be seen… But we need to keep trying to convince people that nature is important, and that not having it is more expensive and economically damaging.
What images come to mind when you think of a field ecologist? Do you see what I see? I see someone, probably in khaki shorts and a broad-brimmed hat, walking through thick rainforest, listening to the calls of birds, waving off insects determined to find a patch of skin to bite, and smelling the exotic aromas of plants and animals living, dying and decaying.
You may well be thinking that this is an idealised image of a field ecologist and while it may have been true 50 years ago, it’s harder to imagine now. After all, every day we hear about habitat destruction and how mankind is damaging the natural environment. But I’d like to propose that even 50 years, or 100 years, or even 1000 years ago mankind was having an impact on the environment and this idea of the ‘natural’ world really needs rethinking.
Take, as an Irish example, the Burren. I visited this area for the first time a few weeks ago and was stunned by the rugged beauty of the place. It was sparsely populated, only a few sheep and cows (and the occasional donkey) provided evidence of any human presence in places; how much more ‘natural’ could one get? Plenty more, it turns out, as the entire landscape is the result of human impacts.
The entire area is littered with signs of prehistoric people, the most striking of which was the 5,000 year old Poulnabrone portal tomb. This tomb dominates a limestone pavement with a view that stretches for miles across to the sea. Yet reading the information boards it quickly became apparent that this was not the landscape in which the tomb was constructed. At that time the area was heavily forested with small clearings made by people to farm and build their homes. The tomb would most probably have been largely hidden from all but those who knew its location. Yet over the next few thousand years people cut down more and more trees to make use of the timber and to clear the way for more farmland. However, the trees were the only thing holding the thin soil in place and with the loss of the trees, the soil soon followed, until all that was left were patches of vegetation and entire hillsides of exposed limestone bedrock. That stunning ‘natural’ landscape is the result of ancient habitat destruction!
Poulnabrone tomb. Image by Sarah Hearne
A similar story can be told across much of the world. New Zealand, adopted home of the hobbits, with its fields and rolling hills, was once almost entirely forest. Yet when the Maori reached the islands around a thousand years ago they proceeded to reduce the forest cover by almost half, and the European settlers reduced it by half again. In addition, the loss of so many endemic species also led to changes in the structure of the remaining forests, though precisely how is still being debated.
It’s the same the word over. Take, as a final example, Australia. The sixth largest country, the world’s largest island, yet it has only 0.33% of the world’s population. Surely humans can’t have had much of an impact there? Well, yes they can, particularly if you think that they are at least partly responsible for the loss of the megafauna. For more details on that I highly recommend Tim Flannery’s 1994 book ‘The Future Eaters’, with the teaser that I never knew that dung was so important to a properly functioning ecosystem! But even ignoring that, Aborigines had a long and close association with the land, heavily modifying environments through activities including the use of controlled burning.
I could go on (and on, and on) for every habitat on almost every continent, but it would get rather monotonous. My point is that when we look at the ‘natural’ word we rarely see something that’s never been touched by man however far into the ‘wilds’ we go. The ‘natural’ world has been modified, sometimes subtly, sometimes dramatically, for thousands of years as countless generations have struggled to survive and prosper. Ecology, however much we like to think otherwise, always involves a human component. Sometimes the humans who made the impacts have long gone and the landscapes have become so normal and ‘natural’ its hard to think there was a time they were ever different. But if we are to understand the world we need to understand the historic impacts we have had, not just on climate, not just in towns and cities, but also on the ‘natural’ world.
Author
Sarah Hearne: hearnes[at]tcd.ie
@SarahVHearne
Image sources
Sarah Hearne
Ewers et al. (2006) Biological Conservation113:312-325
