Cyanobacteria or simply known as blue-green algae may have formed the oxygen into the early atmosphere. This is because these micro-organism has the capability to photosynthesize wherein they can produce oxygen and carbohydrates. In fact, all the plants contribute in the fomation of oxygen.
Answer:
3.Flood
Explanation:
Flood is the catastrophic event which is the main cause of the most weathering and erosion in the least amount of time in this ecoregion because there is no vegetation present in this region and the soil is vulnerable for erosion. Flash-flooding and rapid runoff are agents of erosion in the Trans-Pecos ecoregion of Texas whenever the rainfall occurs. Vegetative is very important for preventing soil erosion so the people of this region has to stop overgrazing in this area in order to avoid more erosion of the soil.
