Monday, June 30, 2008

Treegod
South Downs
The South Downs are chalk hills in the South East of England. They range along the coast, through Sussex, then they u-bend in Hampshire and end up as the North Downs in Kent. In between the two Downs there is the Weald, filled with much farmland and the traditional English patchwork landscape.
Some years ago my dad owned a flock of South Down sheep, a breed traditionally associated with the South Downs. With these sheep we grazed some of the South Downs as part of a Conservation policy planned by Conservation organisations that manage the South Downs. From this I learnt a lot about the ecological history of the Downs. I also spent time with conservation volunteer groups, scrub-bashing (clearing scrub) on steep slopes to help preserve the grassland habitat.

Centuries, even millennia, ago, the Downs, like much of Britain, was a sea of trees, interrupted only by “islands” of other habitats and human settlements. In time, human agricultural practice changed, and much of the Downs became dominated by sheep grazing, seeing the loss of much of the old forest. Over time, this new land management created a new ecosystem, one traditionally associated with chalk grassland. The fertility went down allowing specialist species to flourish on low fertility chalkland.

This special ecosystem flourished for quite some while, until the Second World War. At this time, the country needed to make its own food and not rely so much on imports from overseas. This meant that land use had to change. Places, like the South Downs, had to give up their traditional agricultural practices and employ intensive arable farming.

Within a few decades, this had quite an impact on the South Downs. Much grassland was ploughed over and given to arable use, whilst other parts, that weren’t grazed, soon transformed into gorse and hawthorn scrubland. Now only 5% of the traditional chalk grassland is left, and only that because it was grazed by rabbits. Had the rabbits not suffered from mixomatosis, there would have been more of this chalk grassland habitat left, with its distinctive flowers, grasses and, of course, the butterflies.

The conservation policy, employed by many conservation groups, on the South Downs, is the maintenance and restoration of the traditional chalk grassland by “bashing” the scrubland and traditional grazing (or mowing) of existent grassland. In fact, here is what it says on one website, dedicated to the conservation of the South Downs;
Brighton & Hove has many areas of what was traditional downland, also know as chalk grassland, a priority European Habitat. The chalk grassland is the product of centuries of sheep grazing. However with changes in agricultural practices most of these areas have disappeared while those that remain have become neglected. Without the grazing the remaining chalk grassland will slowly deteriorate as nutrient levels build up favouring coarser species like nettle and bramble at the expense of wildflowers such as cowslips and violets. While reintroducing grazing would be the best solution it is often not practical in the short term. In these cases the grass is mown instead with the cuttings removed. This helps keep nutrient levels down as well as preventing scrub (hawthorn, blackthorn etc) becoming established. http://www.brighton-hove.gov.uk/index.cfm?request=b1000289

Think Globally, Act Locally
From the local view of conservation, this makes a lot of sense, to continue the traditional ecosystem as it has been from centuries and maintain its beautiful and unique biodiversity. However, this policy doesn’t seem to meet the needs of our current global environmental problems. Part of the problem is deforestation, and this in turn is damaging the Earth’s ability to recover from the amount of CO2 and other greenhouse gases that are being pumped into the atmosphere by human combustion. So by stopping the natural processes of the Earth from turning the South Downs from grassland into forest, that it could become, the process of burying CO2 into the Earth and keeping the Earth at a liveable temperature, is impeded.
I do not propose that current policies are wrong. I may be wrong and the traditional way of maintaining chalk grassland has no real impact on, or is beneficial to, the global climate. This requires research. What I do think is that local conservation policy should be aligned with the wider global situation, of which it is a part, so as not to follow its own isolated agenda.
Human ecosystems have replaced non-human ecosystems extensively and this includes the chalk grassland of the South Downs. As an ecosystem, it is not as efficient as non-human ecosystems in keeping the Earth's living systems in a liveable state. With this in mind, instead of seeing the traditional chalk grasslands as deteriorating due to neglect, it could be said that its ecology is entering a new phase appropriate to the current environmental and agricultural situation. Once upon a time the South Downs was a sea of forest, like much of Europe. The humans started to transform the landscape, bringing a new phase in the South Down’s ecosystem, chalk grassland. Now that grazing is not needed on the Downs, a new ecological phase is being entered into, where the original forest processes, that dominated the British Isles before human agriculture, are starting to come back into their own.
In his book, Revenge of Gaia, James Lovelock talks about dividing England into three parts, one part for the production of resources, like food and energy, another for human habitation and another for the Earth to establish its own non-human ecosystem, non-human being my own emphasis. Places that aren't needed for human habitation or resource production could be left completely unused by humans and left to its own devices, and this would include nature reserves and national parks. Any management needed would not be to restore or maintain the habitat, but to allow for human access, as I believe it is important and healthy for humans to interact with nature, even if just for a walk. But I'd also suggest that there'd be places where no human can enter, leave it completely wild, akin to the demilitirized zone along the border between North Korea and South Korea, something very difficult in England as every square inch seems to be inhabited by human action, even some of the more "wild" places.
Really, this isn't about the South Downs, it's about how local conservation fits into a global scale conservation and how local groups and organisations can align their policies and actions within the wider global view of things. There is much globalisation going on, politically, culturally, technologically and even environmentally. There is a growing emphasis on global cooperation between nations, manifested in organisations like the UN, European Union and others. In this world, we cannot afford to ignore what's happening in other parts of the globe, because the world is becoming a smaller place. We especially cannot ignore the threat of climate change in favour of our sentiments of localised conservation "traditions," that may be outdated in our present situation. The global situation may not suit traditional local situations, but it’s a small price to pay to preserve the Earth in its current state of environmental regulation.
Dangers of Generalising Local Issues
But just to show that local conservation cannot be generalised, I'll make a contrast between the South Downs in England, where I used to live, and the Prades Mountains in Catalonia, Spain, where I live now. The South Downs global conservation policy could be one of letting the deciduous shrubs and trees naturally grow, that would then produce more O2 than the grass and bury more carbon than the grass.
However, the Prades Mountains may need more work. It has an abundance of evergreen trees, but in today's world, deciduous trees are needed as they are more effective at burying the carbon to help reduce CO2 in the atmosphere. In this situation, there may need to be a plan to replace the dominant evergreen trees with deciduous trees to better facilitate the burial of carbon. Perhaps recreate the oak and laurel forests that apparently were here before forestry industry cut them down and replaced them with more productive pine trees.
But my work is not to remove the evergreens, we need every tree we have. No, I have in mind to plant more deciduous trees and direct the competition in favour of the deciduous trees already growing. I will never see my area of the Prades covered in deciduous trees, but at least I can make steps in that direction and research the local environmental situation.
Where the Downs may need to be left to its own devices, the Prades may need some work. But don't take my word for it, I've barely scratched the surface. This has been mainly a hypothetical excercise, to investigate the possibility of aligning the conservation of local ecosystems with the Earth's global ecosystem. I probably don't know near enough things about how local ecosystems fit into global ecosystems, but this is where I can start to know.

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