If an ecosystem is totally destroyed, and the soil is gone, rebuliding the ecosystem starts with?

Repairing and replanting wetlands, creek beds, forestland, and other habitats. Eradicating invasive species. Replacing turf grass with native species. Planting rain gardens to absorb rainwater running off roofs or asphalt.

a. decomposes use carbon from dead organisms as fuel for cellular respiration, returning carbon dioxide back into the atmosphere.

the cell cycle is the final answer! : )