Food/Decentralizing food production
While this article gives suggestions on increasing food yields, the fact is that we already have enough food to feed everyone on the planet [1]. The problem, unsurprisingly, is distributing it.
The problem in distributing food can be sidestepped by small-scale local production. Where production is decentralized, distribution is built in to the production system. If everyone has food available to them locally, food security is ensured; no one need starve due to the inefficiency and injustice of the distribution of our food-resources.
Decentralized food production would mean a reduction in transport costs. Transport is currently a main contributor to the price of food (up to 77% of the total value of the food in sub-Saharan Africa [2]).
Decentralization would also preserve the freshness and nutritional value of our food without the need for preservatives or energy-expensive refrigeration.
Statistics are sketchy, but a very significant fraction of the world's food currently spoils before it can be consumed. One estimate is that 35-40% of food produced in India spoils [3]. The Stockholm Institute estimates that 56% of food grown worldwide is wasted in distribution[4]. Decentralizing production will go a long way towards reclaiming this food for people.
A surprising trend that has emerged in recent years is urban gardening: city dwellers are starting to grow food on balconies, rooftops, roadsides, parks and any little patch of bare soil they can find. Urban gardens may be part of the food puzzle in the future (and, moreover, they serve a social and recreational function) but it will require controlled-environment agriculture for cities to produce all the food they need.
Moving food production away from large farms and towards gardens, greenhouses and small farms would also increase yield. This is because smaller farms are consistently found to be more productive [5][6][7][8][9]. Striking evidence of the superiority of small gardens over farms is found in the survey conducted annually by the National Gardening Association of the USA. They found that America's 1839 million m2 of food gardens produce $21 billion worth of food[10]. By comparison, America's farms, though they take up 2000 times more land[11], produce only 10 times more food[12]. Gardens are 200 times more productive than farms.
It is clear that more food gardens could abundantly supply food without any need for farms. Where would the space for these gardens come from? One answer is to convert lawns to food gardens. The United States of America has 128 billion m2 of irrigated lawn[13]. This is nearly 70 times the size of the existing food gardens that already produce 10% as much as all of America's farms. What if these lawns were converted to food gardens?
Cuba has become self-sufficient in fresh, organic, local food by building small agroecological farms in rural areas, and plenty of private and communal gardens in urban areas, all supported by free advice on best practises in agroecology. Such a system can allow all but the most densely populated areas to be self-sufficient for food; Cuba is living proof that such a model works. Megacities call for a more high-tech approach to self-sufficiency; controlled-environment growing (and eventually in-vitro meat) can allow city-dwellers to grow their own food literally in their kitchen. Rare and specialised plants can be imported using efficient, automated transport, but any area can provide the day-to-day needs of its people. This has benefits beyond just food - it is widely reported that getting locally-grown food direct from the grower, or even from one's own back yard, gives a positive sense of community and empowerment. It also seems to create a sense of connectedness to nature. Though these 'soft' benefits are more difficult to prove or to quantify than statistics on food production, they are not to be ignored.