Energy flows, nutrients cycle. This is how we can define working principles of an ecosystem in a nutshell. Our planet has a very complex land-air-water interaction and we are only beginning to understand the behavior of these systems by simplifying them in enclosed systems such as Landscape Evolution Laboratory (LEO).
Due to its proximity, the Moon appears to be the most convenient celestial body to colonize. The Moon is so close that it can even occasionally get shielded by the Earth’s magnetosphere. Mars has weak magnetic shield in only a few places spread around the planet. Radiation remains as a big challenge for future space colonists. Moreover, psychological effects of long-term space travel is also a big challenge waiting to be understood. Moon on the other hand is only 3 days away.
The Moon’s permanently shadowed regions haven’t been exposed to sunlight in millions, or even billions, of years. The Earth’s 23.5° tilted axis allows sunlight to reach everywhere on its surface including the poles. But the Moon’s tilt relative to the Sun is only 1.6°, not enough to get sunlight into some deep craters near the lunar poles. These regions are some of the coldest, darkest places in the solar system. Volatile chemicals that would normally vaporize and lost into space such as water become trapped in these dark regions in solid form.
On 24 September 2009 the Indian Space Research Organisation’s (ISRO) Chandrayaan-1 had detected water on the Moon. Instruments on Lunar Reconnaissance Orbiter (LRO) can measure temperature, reflectivity, and neutron absorption and have detected presence of Lunar water in massive quantities. The volume is estimated to be around 600 million metric tonnes in the form of water-ice.
Now that one of the most important ingredients for life as we know it is present on the Moon, it is time to push the Human frontier. Antarctic field stations and the International Space Station are ideal research and development places in this endeavor. The most crucial is to apply ecological principles to establish a self-sustaining life support system. For us the Earthlings growing plants in these new habitats is a prerequisite. Plants were sent to space numerous times in the past.
One such ambitious project is called Lunar Greenhouse running by the researchers at the University of Arizona’s Controlled Environment Agricultural Center (CEAC). The team built a prototype lunar greenhouse in the CEAC Extreme Climate Lab that is meant to represent the 18 feet (5.5 meters) of one of several tubular structures that would form part of a proposed lunar base. These tubes would be buried beneath the moon’s surface to protect the plants and astronauts from deadly solar flares, micrometeorites and cosmic rays. As such, the buried greenhouse would differ from conventional greenhouses that let in and capture sunlight as heat. Instead, these underground lunar greenhouses would shield the plants from harmful radiation.
Such systems would be very productive. In principle, it is possible to optimize every needs of a plant: light, water, nutrients including the levels of carbondioxide. Light harvested from the dishes on Moon surface can be filtered and beamed onto plants using fiber optic cables. This concept is not new. Oak Ridge National Labs has an already working system called HSL 3000. Moreover, many private companies such as Sundolier, Solatube, Sun Central, Parans and Himawari are building their business base through indoor lighting. The light would be adjusted to have maximum photosynthetically active radiation. This would prevent photoinhibition where photosynthetic light reactions in light harvesting complexes on chloroplasts are overwhelmed and fry key reaction center proteins.
In order to mimic material cycling and energy flow taking place in ecosystems it is imperative to take a look at into certain systems that are complex enough to represent real world but simple enough to manipulate and understand. Hawaii archipelago is one unique place on our planet that represents almost every type of habitat present on earth from arctic tundra to deserts to tropical rain forests. In this setting Hawaiian traditional agricultural practice of sweet potato farming is quite distinct. In Kohala, Hawaiians adapted and modified the landscape to optimize and maximize rain-fed agricultural production in a very small unit of area. Hawaiians in a sense invented hydroponic agriculture in which now we are trying to apply to space systems.
Kohala agriculture, carried out intensive sweet potato farming in a narrow, diagonal strip of land about 10 miles long and 2.5 miles wide for about 600 years. This fertile region, which stretched from sea level to an altitude of 3,000 feet, occupies a fraction of the volcano’s slopes. The early inhabitants of Kohala had discovered a “sweet spot” of high soil fertility – a section of land carrying a soil rich in phosphorus and bases, which received enough precipitation to harvest vast quantities of sweet potatoes. That rare combination of rainfall and fertile soil did not exist on other islands such as Kaua’i, O’ahu and Moloka’i. Public projects to revive Hawaian traditional agriculture is underway.
In short, we must learn to be more productive in less area using less energy. Now back to the Moon.
NASA Commentator Lori Meggs at the Marshall Space Flight Center talks about the latest work of the Veggie experiment on board the International Space Station with Gioia Massa, the Veggie project scientist. The experimental compact greenhouse has been used successfully to grow two crops of lettuce and a crop of zinnias, demonstrating an ability to grow crops in space that could be very useful for future exploration missions out into the solar systems. More tests are on the agenda as specialists improve the capabilities of the system: