Look at what we get from the natural systems around the world – supplying food, keeping the growing world working, reducing the effect of weather on our lives and even helping to keep us happy.
These 'services', which we essentially get for free, are described in the Millennium Ecosystem Assessment, a United Nations project that started in 2001.
Without these services we wouldn't have a habitable planet, but, as the world population grow
s, two things are happening to threaten the future of these natural systems and the services they provide.
Firstly, more people means more demand for land and resources from the natural world. The land gets used for towns, cities and agriculture, while ever more fishing, hunting and forestry are ways in which natural resources are used up.
Secondly, more people means more waste, pollution and greater production of climate change gases, all of which we release into one of the Earth's major systems – the air, water or land.
If we take these two sets of demands together, we can work out how much of the Earth, land and sea, each of us is using to provide the resources we are consuming and absorb the waste we are producing.
This is our ecological footprint.
The most recent set of calculations show that in 2005 the area with standard productivity and capacity to absorb waste we each needed worked out at an average of 6.7 acres per person. Looking at the calculation from the other side – just how much space is there in the world with this standard productivity and capacity to absorb waste – gives another figure. This figure, what is called the biocapacity of the world, is 5.2 acres per person.
Comparing the two figures we can see that the world's ecological footprint is about 30 per cent bigger than the world's biocapacity. In other words, we are using more space than we actually have and, in much the same way as if we were spending money we didn't have, we are building up a debt.
It was a little over 20 years ago that we first went overdrawn on our ecological bank account, but since then we have been consistently in the red – this is an unsustainable debt and we need to take steps to stop it growing and begin paying it back.
John Elliot
(chairman, Scottish Borders Environment Partnership)
Briery Place
Duns
