Paving the land - and taking it back again

"Restoring to fertility land covered with concrete is an enormous task, but not an impossible one. So, Lorenza Zambon, actress and gardener, tells the story of a couple in Turin, Italy, who decided to give to their children a patch of fertile land as a gift. It was a lot of work; concrete had to be cut and broken to pieces and the rubble carried away. Then, restoring the fertility of the soil took truckloads of dirt, charcoal, and more. Zambon doesn't tell us how long the task took nor how much it cost, but surely it was slow, messy and expensive. It was also a subversive idea: in the generally accepted view, paving the land means "developing" it, and that means making money. So, destroying property to restore the fertile soil is something that nobody in his/her right mind would - normally - do."

writes Ugo Bardi on his blog post about the increasing encroachment on agriculture land by roads, houses etc. It is very hard to get accurate data for exactly how much land is paved over or "built" in the world. Data from Denmark looks like this. 

Danish land use (ministry of environment 2004)

 4.1 %, 4.3 % and 4.4 % of the EU territory was classified as artificial surface in 1990, 2000 and 2006 respectively. This corresponds to a 8.8 % increase of artificial surface in the EU between 1990 and 2006. In the same period, population increased by only 5 %. In 2006 each EU citizen disposed of 389 m² of artificial surfaces, which is 3.8 % or 15 m² more compared to 1990. Unsustainable land use trends can be observed in Cyprus, Denmark, the Netherlands and Portugal where land take is growing considerably faster than population growth. Furthermore, there are several new Member States also affected by unsustainable land use trends due to continuing land take and at the same shrinking populations. Policy targets for land take. Quantitative limits for annual land take exist only in six Member States: Austria, Belgium (Flanders), Germany, Luxembourg, the Netherlands, and the United Kingdom. In all cases the limits are indicative and are used as monitoring tools. This can be read in a recent EU report. I write more about this report in the post EU farm land increasingly sealed. 

In Garden Earth I write:

Roads and petrol stations—the crops of the modern times

The statistical basis for assessing how much land human beings have taken in direct use for buildings, roads, etc., is surprisingly weak. Literature quote figures from 1.5% up to 9%. In Sweden 3%, 1.29 million hectares of the land, is built on in some way. Land for housing was 29% of this; roads, railroads and airports 31%; industries, etc. 11%. Of course, Sweden is sparsely populated. In the county of Stockholm 15% of the land is built upon whereas in the northernmost county of Norrbotten only 0.6% of land is built upon. There were 550,000 kilometres of roads (some 60 metres per person) covering 345,000 hectares of land (SCB 2004). In the more densely populated Denmark, human infrastructure is calculated to cover almost 20% of the land area (Danish Ministry of Environment 2005). During the 1960s, 7% of European farm area was encroached upon by roads and 15% of the agriculture land of Great Britain was built upon (Montgomery 2007). By 2010, the United States lost almost 10 million hectares, more than 2.5% of farmland, to human infrastructure since 1950 (Talberth et al. 2007). Eastern United States has a larger proportion of its total area (4–5%) in urban and suburban landscapes than in other regions (H. John Heinz III Center 2008).

We need to do something with the ongoing encroachment of agriculture land by built infrastructure. It is scandalous that soils are not protected by any international conventions. As far as I understand it is not even on the agenda in the upcoming Rio + 20 meeting.
Time for a soil convention!

Update 19 April:
Apparently the EU Commission released some guidelines about "soil sealing"
http://ec.europa.eu/environment/soil/pdf/soil_sealing_guidelines_en.pdf
and there is an upcoming conference about it:
http://ec.europa.eu/environment/soil/conference_may2012.htm