Ecopoiesis is the creation of a stable, enduring ecosystem, and is the last stage of a terraforming process. It's achieved through a series of successive ecological changes which depends on available resources and the initial environmental conditions:
The first stage of succession is the introduction of colonising species. These are the "bottom-of-the-food-chain" species. The ones that don't need other species to survive, grow and reproduce. They're used to stabilise loose soil, oxygenate the air, provide food and organic material for the next wave of species. Environmental conitions during the inital stages of ecopoiesis will fluctuate dramatically and be unpredictable. All colonising species will need to be highly adaptable to survive. Some species are so adapted to extreme conditions that they deliberately alter their surroundings to produce a hostile environment, allowing them to thrive with minimal competition. Australian Eucalypts are a perfect example. Eucalypts are a fire promoting species. They produce flammable oil soaked bark and drop tinder-dry leaves. The build up of highly flammable debris quicks turns a small fire into a raging wildfire, destroying all non-fire tolerant species. Uncontrolled wildfires are very undesirable in the early stages of ecopoiesis. Eucalytps and other fire-promoting species should not be introduced until the late stages, if at all. First stage species include: plants and algae. Plants will need to be small, non-flowering (as there are no insects yet). Lichens are not a colonising species. They are very slow growing and have highly sensitive environmental requirements.
The next stage doesn't begin until a protective layer of Ozone (O3) is established in the upper atmosphere. The second stage is the introduction of competing species. These are the species that feed on, or directly compete with, the colonising species. Second stage species include: Herbivorous animals (including some insects), flowering and tall plants, and fungi. Each species should be introduced after their food sources are well estalished. The population of each species will also fluctuate, some may collpase and may need to be reintroduced. Species with specialised diets are far less likely to survive than opportunistic feeders. This is the stage when human bases are established. Human numbers are heavily restricted and dependant on external supplies of food and materials.
The third stage is the introduction of diversifying species. These are the species that have no specialised function but add diversity to the ecology of the planet. Diversity is the key to a stable ecological system. Third stage species include: Carnviorous animals and Lichen. The higher up on the food chain a species is, the less likely it is to survive the early stages. A carnivores survival is dependant on the continued supply of animals for food, who in turn are depedant on the continued supply of plants, some of which are dependant on the symbiotic relationship with bacteria at their roots. An interruption at any of these points will impact heavily on the carnivores at the top of the food chain. The third stage is when human colonisation occurs.
The fourth stage is the final and on-going stage, evolution. The new planet has its own set a environmental parameters that off-world life is not perfectly acclimitised to. Over the next few million years introduced life will evolve into every niche the planet has to offer. New species will evolve and old ones will die out. Eventually, we hope, the inhabitants of this planet will terraform and colonise other planets, taking their new species with them. To start the next cycle of Autopoiesis.