The amount of usable cropland is declining. Land is getting harder to come by. Germany alone loses the equivalent of 70 hectares of land to road construction and urban development each day.
At the same time, the demand is growing for land to grow crops for use in food, fuel and textile production. This demand can be calculated in what's known as the land footprint: for example, the amount of land necessary to maintain our current standard of living. Europe has a rather large footprint. Only forty percent of the land devoted to mainting Europe's consumer society lies on the continent itself.