The hoop represents a balance in nature for both human, animal, plant and the universe. The hoop is a circle, an infinite loop that goes on forever when the pieces that help create and maintain the hoop are in balance.
These balances can be represented by a familiar set of earth, wind or air, fire and water. In order for anyone of these elements to occur, they need to be in balance with one another and sometimes allow the others to flourish or grow and diminish or disappear. Such as air can help fire grow, whereas water can destroy fire.
The hoop is the balance in life. On a much more human-scale, it is the balance that people have with nature. If people hunt too many animals, there will be no animals, so while now there may be a feast for the people, in the future they will be hungry or starve. If land is over-planted or overused now, the land in the future may not produce.
The hoop represents balance in aspects of life and interaction of human beings with the world that surrounds. And also can be broken or disrupted when humans are not in balance with the world around them.