Category Archives: agriculture

Garden cities and forest gardens

In Ebenezer Howard’s Garden Cities of Tomorrow (1902), we can read his proposal to surround a 1,000-acre town of 30,000 residents with 5,000 acres of farm land. Since in space industry and agriculture will mainly be located outside space settlements, we could look for alternative uses for this land.

Howard pays little attention to recreation in his book. Though his design includes a central park, his garden city plan does not reserve land for sports such as field hockey and ultimate. Because sport does positively affect human wellbeing, we propose to reserve some of the land originally reserved for farms to sport fields.

In chapter 10 of his book The High Frontier (1976) O’Neill suggests that space settlements are ideal locations for gardening. Our suggestion would to combine “O’Neill” and “Howard” by reserving a substantial portion of the “farm” land for allotment gardens. These are gardens assigned for individual, non-commercial gardening.

O’Neill also advocate the concept of polyculture in his book. Polyculture is the practice of growing of multiple types of crop in the same plot of land. It’s the opposite of monoculture, which dominates modern agriculture. Scientific studies have shown that polyculture is preferable to monoculture.

There are several types of polyculture, one particular interesting concept are forest gardens. The practice of forest gardening is an ancient one, but Robert Hart has formalized it in his seven-layer outline. The first layer consists of mature fruit and nut trees, which (of course) will provide fruit and nuts. The second layer consists of smaller trees, while the third layer contains fruit bushes (currants and berries). Then the fourth layer are perennial vegetables and herbs. The fifth layer are root vegetables, the sixth are edible plants which grow horizontally. The final layer consists of vines and climbing plants.

Forest gardens is considered as a low maintenance type of gardening, and hence suitable for allotment gardens. Most people with allotment gardens, work there in their spare time. An additional benefit is that forest gardens contribute to food security by providing a wide variety of food. Potentially forest gardens could be established on rooftops.

Forest gardening is a type of agroforesty, the combination of agriculture and forestry in one system. Agroforestry does not need to limited to non-commercial allotment gardens, the utilization of non-timber forest products in forest farms can make forests management commercially interesting. We propose that forest farms should be leased to private parties, on the condition that these forests will be open to the public (see also our post on Allemansrätten).

Timber and paper in space settlements

The inhabitants of space settlements need to establish their own supply of wood, both as timber as for the production of paper. Importation of wood from Earth will be a costly affair, and unfortunately it takes several decades for trees to grow to commercial height. Alternative sources for tree wood have to be found.

We can use hemp as a resource for production of paper. One advantage of hemp is that it is a fast growing crop. Further hemp has a lower lignin content than wood. Lignin is an unwanted substance in paper, and hence has to be removed from pulp. A serious challenge is that hemp has a low cellulose content (relative to wood), however, through genetic engineering the cellulose content of hemp might be increased.

Another application of hemp is the production of fiber boards. Fiber boards can also be made of bamboo, a fast and high growing grass. Certain types of bamboo, known as timber bamboo, can be used as timber either directly or as resource for engineered wood.

Another alternative for tree wood is rattan, also a fast growing plant. Furniture and baskets made of rattan are well-known, and there is no reason why space settlers will like them less than terrestrials.

Roof gardens and efficient land use

A standard O’Neill cylinder provides about 321.6 square kilometers of usable land. For comparison the surface area of Singapore is 716.1 square kilometers. Since a standard O’Neill cylinder contains only a small amount of land, efficient land use will be essential. (Larger cylinders can be built, but they are unlikely in the early stages of space colonization.) Continue reading Roof gardens and efficient land use

Time zones and separation of functions

One of the major advantages of space colonization by the use of free space habitats instead of planetary “space” colonies, is the separation of functions. Gerard O’Neill already advocated that residence, agriculture and heavy industry should be separated from each other, i.e. that agriculture and heavy industry should not be done in the same structure where most residences are located.

In regard of the separation of agriculture and residency, O’Neill gives two main arguments. First, in a space settlement we have full control over both climate and day length. However, the climate preferred by most citizens is not necessarily the most optimal climate for the cultivation of crops. Second reason is pest control. If in an isolated space farm a pest will occur, it will be easy to deal with it by sterilizing the farm by increasing temperature above the limit life cannot survive. It’s quite obvious that we cannot do this, in a space habitat populated by humans.

For the separation of heavy industry and residency, the arguments are even more straightforward. Heavy industry impose a great danger to health and safety through its pollution and potential of explosion and similar disasters. By banning heavy industries from space habitats, we create a clean and save environment for people to live.

A second argument put forward by O’Neill is related to his proposal to divide space settlements over three time zones, with a 8-hour difference between each successive zone. Because heavy industry is located outside any space habitat, they can be in continuous operation. And if the industry hires shifts from different time zones, night work which is considered as unpleasant by most, will be avoided.

O’Neill imagined that space settlers employed in heavy industry, would commute each day between their home and their workplace. But technology has improved much since the mid 1970s, that nowadays much work can be automated and where people are still needed teleoperation will allow workers to run factories without leaving their space habitats or even their homes.

Besides the desire the avoid night work, there’s another reason for dividing space settlements among different time zones (which surprisingly is not mentioned by O’Neill). The principal power source of space settlements will be solar power. And since there’s no night in space (in space settlements night has to be created by covering the windows), space based solar power plants will run continuously and hence have a continuous output. But the demand for power is not continuous over the day, causing surpluses at some moments and shortages at others.

If we divide the population of three time zones with an 8-hour difference, the power demand curve will be flattened. This because if one settlement is facing a power shortage at some point, it’s likely that another settlement has a surplus since their population is experiencing another phase of the day.

Space colonization and genetic engineering

Although Space colonization and genetic engineering are separate concepts and the creation of space habitats is perfectly possible without the use genetic engineering, we believe that genetic engineering is a key technology for the success of Space colonization. Continue reading Space colonization and genetic engineering