Leaves change colors in the fall primarily due to the breakdown of chlorophyll, the pigment responsible for the green color in leaves. As days become shorter and temperatures drop, trees prepare for winter by slowing down their photosynthesis process. This leads to a reduction in chlorophyll production.
As chlorophyll breaks down and diminishes, other pigments in the leaves become more visible. These pigments include:
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Carotenoids: These pigments produce yellow and orange colors. They are present in leaves year-round but are masked by the dominant green chlorophyll during the growing season.
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Anthocyanins: These pigments can create red and purple hues and are produced in response to certain conditions, such as bright sunlight and cooler temperatures. The production of anthocyanins during fall may help protect the leaves from excess light and aid in retaining nutrients before the leaves fall off.
The combination of these pigments and their varying concentrations contribute to the beautiful array of colors seen in fall foliage, varying from bright reds and oranges to yellows and browns, depending on the tree species and environmental conditions.
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