Why do leaves change color?

Middle of September is usually the time when one can feel Fall coming. Fall is close and I am curious, whether you have ever wondered why leaves change color at this time of the year. Leaves contain many pigments in their tissue and during the growing season the green one dominates. Chlorophyll is taking an important part in the photosynthesis process and is part of the light harvesting complex. It is chlorophylls that makes plants and leaves green. During the photosynthesis process chlorophyll breaks down and has to be systematically produced. Shorter daytime and lower temperatures turn plants into their "energy saving mode". The transport of water and minerals from the roots to the leaves will be gradually reduced and finally stopped. The chlorophyll reserves in the leaves will be gradually used and not renewed. The lack of the dominating in the vegetation season green pigment reveals other pigments that determine the leaves' color in Fall.