Huge cities & Huge pressure on agriculture

World population is over 7 billion and increasing fast - you can take a look at how fast in Population Matters' website counter and the trend will not slow down. By year 2100 between 9 to 11 billion people are expected to cohabit the only Earth we have. This means that food demand will also increase and today we are already struggling. It is also anticipated that most of the people will concentrate in megalopolis posing an even bigger challenge to food security and supply. As if this was not complex enough: climate change, international free trade agreements, misplaced subsidies, water & energy scarcity, misused land space -specially in cities-, hazardous pesticides, among other things add up. Some entrepreneurs, governments and companies from all around the World are seizing the issue as an opportunity and they have come up with good solutions like growing food on the roofs!The roofs!

Lufa Farms, a Canadian firm whose vision is "To grow food where people live and do it sustainably"- built two rooftop farms in Montreal & Laval. Their fields amount to 6,000 m2 where they are growing 190 metric tons of fresh vegetables every year. The team got together in 2009, the next year the construction of the first rooftop began and in April 2011 they delivered their first that-day-harvested crops to 400 happy Montrealers. In 2013 they opened the second and biggest rooftop. They use hydroponic cultivation, it consumes 50-90% less water than traditional methods besides the system captures rain water and recycle it. Using biological pest control they cope with unwanted bugs avoiding pesticides. Montreal winter temperatures can go as low as -30C but still their energy use is low thanks to energy curtains, good heating systems, insulation and according to them being in the city (because of buildings and roads nighttime temperatures are relatively higher than in the fields). Finally they compost in-house their organic residues using it in potted-herbs or sold.In London, UK a start-up called GrowUp Urban Farms is using aquaponics to grow "sustainable food for a local market". This growing technique combines aquaculture (raising fish) and hydroponics: it is a closed loop where water is recirculated from one system to the other. They started in 2013 and set-up the first Box to demonstrate the concept financed by supporters through a Kickstarter's campaign. Today they supply herbs, salads and tilapia to local restaurants and have plans to build London's first commercial urban farm.Food-solutions

Both start-ups grow food in a responsible fashion including the distribution and the relationship with their clients pushing for a change in mindsets on how people relate to the food they consume. It is in us, regular citizens to help this kind of initiatives thrive and lower the pressure on traditional agriculture. There is always a solution and these are just examples. We only have one Earth with finite resources and using what we have wisely is something we must do in order to support global population and have a fair life for all.