Almeria's Agricultural Revolution

Thanks to J for preparing today's blip, direct from Almeria, Spain:

"My ride today took me West of Almeria and up a mountain from which I took this picture.  If you look down the valley, you will see a large white expanse in the distance.  Viewed from space, the area appears to be a huge salt marsh – what else could vast white plain on Google Earth be?
 
This is no salt marsh.  These are the hydroponic greenhouses that cover over 260 square kilometres of a cape that includes the towns of La Mojonera, El Solanillo, Roquetas de Mar, and Almerimar.  Apart from the few scattered towns, the entire cape is covered with translucent plastic sheeting under which a huge variety of vegetables are grown, harvested, and sent throughout Europe and overseas.  The cape is the largest concentration of greenhouses in the world. 
 
The climate of Almeria is ideal for greenhouse growing:  The region gets over 3000 hours of sunlight each year and with daytime temperatures rarely below 15 C, there is no need to heat the greenhouses.  Each greenhouse can grow up to three crops per year.  Most of them are owned by individual farmers or cooperatives.  There are however, some large scale operators as well.  Overall, greenhouse farming contributes around 2 billion Euros to the local economy and grows more food than any alternative method.
 
One, of many, downsides is that Almeria gets very little rain.  Most of the water for the greenhouses comes from natural underground aquifers that channel rainwater and snowmelt from the Sierra Nevada mountains to the coast.  Intensive farming is threatened by the drying out of this water source.  Using drip systems limits waste of water but the drain on the aquifers is immense.
 
Vegetable farming is also very labour intensive.  Living conditions of foreign, mostly African, farm workers are sometimes haphazard and undocumented workers face exploitation.  Close regulation of the industry alleviates the worst of conditions and farmers employing undocumented workers can lose their access to produce buyers.
 
Other issues that need to be addressed is the rapid deterioration of the plastic sheeting in direct sun and the difficulty and cost of recycling. "