The final step in terraforming is the insertion of Earth-like life forms. If everything went well, this final step will transform a once dead planet into a new garden of Eden, ready for the first humans to come.
Organisms used during terraforming processes Edit
Before we bring Earth-like life to a planet, we might have used genetically modified algae and bacteria for Ameliorating The Atmosphere. These organisms can split carbon dioxide into oxygen and Atomic Carbon and can split ammonia into nitrogen and hydrogen.
Before inserting life Edit
We have to keep under consideration that once we insert plants, they will absorb a significant amount of carbon dioxide, decreasing global temperature. Also, plants will bring moisture to the air and will lower temperature. Soil erosion will not be as powerful as before and rocks will start to be transformed.
Before inserting the first plants, we must have enough carbon dioxide so that after the planet is colonized by vegetation there will still be enough to sustain the carbon cycle. We must keep a higher temperature (by using less greenhouse gasses for example), so that we will have the required temperatures after plants conquer the world.
Inserting plants Edit
At first, plants will find hard to live, because there is no soil like on Earth.
- The first organisms that will be sent are bacteria, algae and lichens. They need less resources and can be sent easily worldwide, as spores. They can grow on bare rocks and create the first organic soil for other plants.
- If there is some soft soil, the first to pour its roots in will be resistant forms of grass. On high mountains, there are species of grass that grow in cracks between rocks, with very little soil. They can survive to sharp climate changes, like freezing temperatures during night and 40 C during day. If there is no soft soil, these plants will find their way wherever there is a crack in a rock, with enough water for a seed to grow.
- Taller species of grass, weeds, can be added at this phase. In fact, there are many places on outer planets where rocks could behave like sand. Moon regolith is a good example. Even if it is not a soft material, it can become with little help from water and a minimum amount of organic soil.
- Insertion of higher plants like bushes is another critical point. They will use soil created by previous plants and will dig their roots far deeper, creating more organic soil.
- Trees are the last type of vegetation that needs to be added. Once trees are added, their falling leaves will create fast a layer of organic soil and their roots will bring minerals to the surface.
The way plants are inserted into their new environment is not by planting, but by dropping seeds. It is enough to drop a seed at every 1 square km. Plants will multiply and will conquer everything. One can see how plants grow on Earth on an exposed concrete slab. Lichens appear first, then plants start growing in the smallest cracks. If the wind brings some sand or dust, that will become a shallow layer of soil for plants. In a few years, you will not notice that there was concrete below. In 10 or 20 years, even trees find their way.
Seeds and spores are carried by the wind or by water on a large distance.
Inserting animals Edit
The planet must be inhabited by plants, before we can add animals. However, some animals will come first. Plants cannot live without them. Bees are a good example. So, insects and worms will be brought nearly as soon as plants are inserted. Insects and worms will be added in small groups and dropped in places with higher concentration of plants, to ensure their survival. Insects and worms can be parachuted in small numbers from an airplane wherever they are needed.
We will have to wait a while for plants to conquer the planet and to develop up to a level where they can sustain animal life. This will not happen at the same moment for each place and for each plant. Animals will be inserted once they have what to eat without destroying the plants. First to be added will be herbivores and not all at the same time. Carnivores will be added later, once herbivores grow in large enough numbers.
Mammals, birds and reptiles will be deployed in a different way then insects. They will be placed as families or groups, at a certain distance one to another, with the help of a spaceship or an airplane. We must ensure that there will be enough individuals of each species to ensure survival.
It is very important to keep invasive species at some distance. Knowing where natural barriers will be is a key element. We must not allow one ecosystem to interact with another in a way that something might get destroyed.
Observing and guiding Edit
The new biosphere is considered mature only when trees have reached maturity and the amount of carbon dioxide remains stable in the atmosphere. Until then, it is still growing.
During this phase, scientists need to conduct surveys, to see how plants and animals are adapting to their new world. If needed, they must interfere. They must also watch other important processes, like climate changes (it will take a while until a newly terraformed planet has a stable climate), ground erosion, hydrology, atmosphere composition and volcanism.
This is the last phase in terraforming and the most beautiful. It is the moment when all work pays off. During this time, scientists no longer live in insulated buildings and can stay outside, breathing clean air. First settlers can come and look for their promised land and a new garden of Eden takes place.