In language, reasoning occurs as statements or premises connect logically and lead to a conclusion. This reasoning can be of different types including cause and effect in which an event, situation, etc. is presented as a trigger of others. In the statement "Gradually, desertification causes a dryland, such as the Sonoran Desert, to lose its ability to support plants and animals" this is the type of reasoning as a cause is presented "desertification" and the effect of it " to lose its ability to support plants and animals" which is also shown by the verb "cause" that shows the cause and effect reasoning.
King using the phrase "flight's ground crew" refers to the people who have sacrificed a lot to make the freedom movement take flight. They are the people who have given their all but are not recognized for their sacrifices.
