The definition of a concubine is a woman who is a mistress to a man with a wife or who cannot be married to her because of a difference in social status. An example of a concubine is one of the mistresses of an important king who has many wives and mistresses. concubine. concubine.
How do you identify a tree species? It is known that mature, leafy trees, such as redwoods, aspens and oaks, are the best producers of oxygen. Additionally, it is known that a tree produces higher volumes when growing than when mature, because converting air and soil into wood causes the tree to produce more oxygen.
The sources of atmospheric oxygen through photosynthesis are phytoplankton, such as cyanobacteria in the ocean, and trees and other green plants on land. The amount that each source contributes is under debate: some scientists suggest that over half comes from oceans, for example, while others put the number at closer to one third.