Difference between revisions of "Food"

Intro

But this story misses a key point: there are far better ways to produce food than the ones now in wide use. While it is true that conventional plough agriculture and monoculture is driving the world towards a food crisis, there are ways to grow food using very little land, very little labour and no pollution. The aim of this page is to explore these methods and show how they can comfortably sustain a growing population. Any food shortage is really a shortage of applying this know-how to food production.

It is possible, with current know-how, to create a food-production system that can provide tens of billions of people with abundant, local, nutritious, tasty food, textiles and wood, while economizing water, restoring soil, building communities, saving energy, creating pleasing landscapes, preserving wilderness, stopping diseases, needing virtually no inputs and benefiting not just people, but the rest of the biosphere as well.

Controlled Environment Agriculture and Automation

Aeroponics is the art of growing plants with their roots in air rather than in soil. The roots are intermittently spraying with nutrient-enriched water. This allows for precise control of the amount of nutrients that the plants receive.

By growing aeroponically indoors, we can create an environment that can be monitored and controlled electronically. This lends itself readily to automation. A controlled environment allows food to be grown year-round, independent of seasons. While only one harvest a year can be grown conventionally, constant-yield growth gives 4-30 harvests a year, depending on the plant. Growing indoors greatly reduces the threat of pests and plant-diseases, eliminating the need for pesticides. And best of all, by optimizing the nutrient flow, we can supply plants with the nutrients they need to produce the flavonoids that give them their flavour. With controlled growing, it is possible to achieve a more intense flavour than growing in soil.

Aeroponics requires an input of water with dissolved mineral salts, but it uses these resources very efficiently. Hydroponics uses only 5-10% the water of agriculture ^[5], while aeroponics uses 65% less water than hydroponics and only a quarter the nutrients ^[6]. Such water-efficient growing will make huge difference if we want to preserve our water resources, as 69% of all our water use is for agriculture ^[7]. Both of the necessary inputs for aeroponics - water and minerals - are in enormous abundance on Earth.

LEDs can efficiently satisfy the light requirements of plants. Experiments by the University of Manitoba found that LED lighting increases yields by about 40% ^[8]. LEDs could be useful in situations where sunlight is unavailable - such as in winter in regions far from the Equator, in underground or underwater dwellings, in cities where a demand for space means food must be grown on stacked shelves indoors, and in space habitats. Currently the main obstacle to large controlled-environment agriculture projects such as The Vertical Farm Project is the cost of energy for lighting. As LEDs become cheaper and more energy-efficient (as with recent developments in OLED and PHOLED technology) these projects become more and more feasible. Fibre-optic cables can pipe sunlight in from outdoors, significantly reducing the amount of energy needed.

Omega Garden uses an innovative cylindrical design in which plants are constantly tilted so they have to adjust to gravity^[9]. It is claimed that this method can result in a fivefold increase over other plants grown in the same conditions but without rotation.

There are many tricks that can be used to increase yield in controlled-environment growing that are not feasible on farms. Increasing carbon dioxide concentration in the air can increase yield 30-50%. Supplementing with fulvic acid can increase yield over 30%. Plant hormones such as gibberellin increase yields significantly.

Note that several plants can be grown stacked vertically, greatly reducing footprint

Dickson Despommier, an advocate of vertical, controlled-environment farming, has painted a picture of what controlled-environment growing might be like -

PodPonics is one existing proof-of-concept; it grows an acre's worth of food in a single 320 square foot (30m²) shipping container. Food produced in this way is local, fresh and delicious.

"Each floor will have its own watering and nutrient monitoring systems. There will be sensors for every single plant that tracks how much and what kinds of nutrients the plant has absorbed. You'll even have systems to monitor plant diseases by employing DNA chip technologies that detect the presence of plant pathogens by simply sampling the air and using snippets from various viral and bacterial infections. It's very easy to do.

Moreover, a gas chromatograph will tell us when to pick the plant by analyzing which flavenoids the produce contains. These flavenoids are what gives the food the flavors you're so fond of, particularly for more aromatic produce like tomatoes and peppers. These are all right-off-the-shelf technologies. The ability to construct a vertical farm exists now. We don't have to make anything new."

Algorithms could be developed and shared online to model how nutrient flow, timing, duration, intensity and color of light, and strains of plants used affects food yields and flavour. PlantLab is a company that is compiling exact, programmable specifications for growing various plants, but open-source methodology has proven to be a much faster way of compiling large streams of experimental data. Programming these algorithms into computers that control the LED lights and the nutrient flow in the aeroponic system would yield a truly automated food-production system that anyone could use to grow their own food indoors. All this technology exists currently, and is being constantly improved and refined.

Permaculture

Most food now comes from large farms that focus on just one or two crops or animals. This kind of farming requires constant inputs: fertilizer, pesticide, water, animal feed and other resources. It also produces a constant output of pesticide-contaminated water and other waste.

It is sometimes assumed that growing food without fertilizers, pesticides or other chemicals that have unwanted consequences means growing them without any yield-increasing methods at all ^[11]. According to this argument, we need higher yields to feed a growing population, and we need chemicals to boost yields; organic agriculture is equated with low-yielding agriculture. However, there is an alternative farming method that is both high-yielding and organic. This method is permaculture and it uses ecological methods instead of chemical ones to boost yields.

Many experts have stressed that to sustain a growing population in a way that is viable in the long-term, we need is sustainable intensification ^[12][13][14]. This refers to a method of agriculture that gives higher yields than industrial monoculture, has less impact on the environment, uses less water and requires fewer inputs. Happily, sustainable agricultural practices also tend to be more productive than non-sustainable ones. An analysis of 286 sustainable farming projects in the developing world found that yields doubled for most plants ^[15]. Permaculture is a system that uses many sustainable intensification technologies together.

Sustainable intensification is being implemented all over the world, with a 50% increase in four years ^[16], and with entire countries like Cuba and Bhutan moving to sustainable systems.

No inputs, no waste

Whereas industrial farms import inputs such as fertilizer and remove waste products such as pig effluent by mechanical means, permaculture designs the farm so that all inputs are provided on-site by another species, and all outputs are put to use. For example, a cow requires an input of grass, and creates an output of dung and urine. By spatially juxtaposing the cow and the grass, the cow's feed is provided by the grass and the grass's need for fertilizer is provided by the cow's manure and urine. This slashes the need for human or mechanical labour. A permaculture farm is an interconnected system of flora and fauna that recycles its own resources - an agroecosystem. In contrast with the large fields of single crops seen in industrial farming, permaculture favours complex patterns where different species are closely juxtaposed in space and time, allowing these synergistic interactions to happen.

Integrated pest management

Species need protection from pests and predators. In a permaculture farm, this too is provided by other species, thus removing the need for artificial pesticides. This is known as integrated pest management  and can solve our problems with pesticides leaking into the environment.

Soil care

Industrial-style farming techniques deplete 6-24 kilos of soil for ever kilo of food grown ^[17]. This is a perfect example of a failure to think long-term; growing food in a way that diminishes the land's capacity to grow food is like killing the goose that lays the golden eggs. Permaculture (as its name suggests), focuses on the long-term fertility of the soil. Permaculture can create 20 kilos of newly fertile soil for every kilo of food grown^[18]. Ensuring that soil has a thick spongy texture has immense consequences for world water use.

Permacultural animal husbandry

Mob-grazing in action. Note that the cattle are clustered tightly together, not scattered like on extensive pastures. This is necessary for the grass and soil to benefit.

Ranching is often blamed for environmental problems^[19][20] because it uses a lot of land and water, can require large amounts of grain feed, antibiotics which leach into the environment and produces runoff that can pollute local water supplies. One argument against ranching is that it requires 16 kilos of grain to produce one kilo of beef, so to preserve food and avoid a food crisis, we must all become vegetarian ^[21].

All these points are valid criticisms of extensive grazing and feedlot farming. However, there is a way of raising livestock that is more in harmony with evolution's design. It is called mob-grazing, cell-grazing, or an 'animal tractor' and works by imitating the natural grazing patterns of herbivores.

In the wild, herbivores huddle close together for protection from predators. In this 'mob', they mow down an area of grass in about a day, then move on to a different patch. The loss of predators has meant that herbivores spread out into a different, extensive pattern of grazing. This caused overgrazing and the destruction of grasslands in large parts of the world. The carbon released by the degeneration of these grasslands is a greater than from all the fossil fuels burnt by industry, prompting authors of a recent paper in Science to say that the loss of predators "may be humankind’s most pervasive influence on nature" ^[22][23].

A large percentage of the world is covered by more-or-less featureless grass pastures dotted with cattle. We can increase the productivity of this land many times over by dividing it up into small cells and moving a succession of cattle and other animals around from cell to cell at very high densities. This will easily allow us to provide enough meat for a growing population. We can introduce more synergies by growing trees on the pasture (known as silvopasture) and by integrating aquaculture in ponds and lakes. Trees provide extra feed for the livestock in the form of leaves, while simultaneously yielding fruit, nuts or timber. Reeds on the edge of a pond grow much faster than grass does, providing even more feed, while simultaneously yielding fish and aquatic crops like taro.

The benefits of this sort of grazing — for grass, for soil, for animals and for people — are remarkable. Manure fertilizes the grass, the mowing causes the grass to shed some of its roots, which then decompose and further improve the soil, and the animals' hooves break up the hardpan on the surface, further improving the structure of the soil. As mentioned in water-efficient agriculture, mob-grazing has been shown to increase the amount of water soil can hold by 775%. The name 'animal tractor' is apt; the herbivores mow and cultivate the ground more effectively than tilling, while also producing meat. This cultivation is particularly needed in sub-Saharan Africa and other places where extensive grazing patterns have made grasslands dry and dead. Anywhere that cell-grazing has been implemented, grasslands have recovered^[24] and the soil and ecosystem holds so much water that drought is no longer a threat^[25][26].

Another key advantage is that multiple animals can graze the same pasture in rotation. Polyface Farms grazes cows, turkeys, pigs, chickens, hens and rabbits on the same space by rotating them in time. This further benefits the soil and allows the animals to benefit from one another. For example, the maggots that grow in cow manure are a food source for chickens. Moreover, it obviously allows much higher productivity per unit of land.

The argument that conversion of feed to meat is inefficient does not apply here, because in such a system cows only eat grass and weeds, not grain or anything else that is edible by humans. Therefore no useful food resources are being wasted. Besides, beef from grass-fed cows has a better nutritional profile than from grain-fed animals and is universally considered tastier. Cows also convert grass to meat much more efficiently than they convert grain^[27]. Similar logic applies to other kinds of meat. We could say that in agroecology, the purpose of animals is to convert inedible grasses, insects, leaves etc. into edible meat. If we are to build a food system that provides high-quality food to all of humanity, it is essential that we use the 335.7 trillion m² of pasture available to us for raising meat sustainably by converting these inedible grasses into meat. One estimate is that this would provide enough food for 1.3 billion people^[28].

• TED talk by Michael Pollan
• The Savory Institute
• TED talk by Allan Savory
• Polyface Farms
• The Rodale Institute

Productivity of permaculture

Permaculture is not only an ecologically sound means of food-production, it is very productive. Permaculture expert David Blume makes a convincing case for the productivity of permaculture, writing, "In a good but somewhat sloppy design, you need about 500 square feet (46.5m²) per person maximum. In a very good design, 200 square feet (18.5m²) will do the job." John Jeavons (father of another school of permaculture called biointensive agriculture), makes more conservative claims of around 316-372 square meters ^{[29] [30]}.

The 2011 UN report on the right to food notes that agroecology initiatives typically double yield within ten years while reducing the need for inputs like fertilizer. It also reports that agroecology projects generally come about as a result of peer-to-peer collaborative sharing of farming knowledge.

While not as automated nor as productive as the aeroponics techniques described to the left, agroecology is a highly practical and advanced methodology that can play a role in making Spaceship Earth work for everybody. In time, it may become possible to automate agroecology by using sensors to detect when plants are ready for harvest, and having robots that can pick vegetables, prune trees and so forth.

Aquaculture and aquaponics

Hydroponics is growing plants in water. Aquaculture is growing fish in tanks. The disadvantage of hydroponics is the constant input of mineral nutrients it needs. The disadvantage of aquaculture is the difficulty of keeping the water clean. Aquaponics combine the two systems and thereby cancels out the weaknesses of both.

In aquaponics, edible fish are grown in a tank. The fish eat the algae that will grow naturally in nearly any still body of water, or pond weeds can be grown. (Most aquaponic systems now use fish food, but methods under development eliminate the need for this input by cultivating duckweed or algae.) The fish effluent enriches the water with nutrients. This water then serves as the medium to grow hydroponic herbs and vegetables. The roots of the herbs and vegetables, and the bacteria that grow around them, clean the water for the fish. Both the fish and the plants can be eaten by humans.

Some aquaponics systems also include a wormery, which uses the inedible parts of the plants to feed worms. The worms are then fed to the fish and the compost they produce can be used to nourish more plants, or made into compost tea to add more nutrients to the hydroponic system. This brings the system closer to a fully closed-loop that recycles all its waste.

It should be apparent from this description that aquaponics is an extremely resource-efficient method of food production. No fertilizers are needed and there is no pollution. It is really the only sustainable way of producing fish; much more sustainable than conventional fish-farming and certainly more sustainable than current fishing practices. In theory an aquaponic system could be run without external input (though in practice fish food and calcium and other minerals often need to be supplied.) Aquaponics requires 10% the water of growing vegetables in soil, because the water is constantly recycled rather than draining away. This means that aquaponic farms nearly anywhere in the world can run on rainwater alone.

Aquaponics is extremely productive. The plant yields compare favorably with hydroponics, and are much higher than growing in soil. Some research even points to the possibility of achieving much higher yields with aquaponics than even with hydroponics^[31]. The aquaponics system at the University of the Virgin Islands^[32] grows over 4000kg of tilapia and over 2500kg of okra yearly. This is more than enough fish for 35 people and more than enough vegetables for four people and it is all grown on just 500m² of space. And this system does not even use space optimally; the 500m² figure includes the gaps between the tanks. Improvements on the University of the Virgin Islands system have since been made ^[33][34]. Growing Power is an urban farm in Milwaukee. It uses several methods of growing, but aquaponics is the main one. On a footprint of just three acres (12,150m²), they grow enough food for 10,000 people^[35].

Over the next few years, as a result of the research that is being done, aquaponic systems will become even more productive, more automated and require less input than current ones. This will make aquaponics even more appealing than it is now.