Thursday, October 17, 2019

Fall colours Essay Example | Topics and Well Written Essays - 750 words

Fall colours - Essay Example Science Content The general perception is that cold weather or autumn is the predominant reason for the colour change. According to The United States National Arboretum, â€Å"while temperature may dictate the color and its intensity, it is only one of many environmental factors that play a part in painting deciduous woodlands in glorious fall colors† (par. 2). This was corroborated by Schwartz who averred that â€Å"although day length, light, temperature, ground moisture and insects all affect fall colours, scientists say that climate change might also be having an impact† (Schwartz par. 22). Source: The United States National Arboretum Source: Schwartz A simple explanation on why leaves change their colour in fall was provided in Science News. As indicated, the rationale stems from the three main pigments in leaves, identified as â€Å"carotene, anthocyanin, and the photosynthetic pigment, chlorophyll, which captures the sun’s energy to make food for plantsâ €  (University of Wisconsin-Madison par. 2). The most predominantly abundant pigment was identified to be chlorophyll which is responsible for giving the leaves the color green reportedly during summer and spring. The article likewise indicated that there is another crucial component in the leaves, auxin, which was a chemical noted to control cells, specifically at the base part of the leaf: the abscission layer. During spring or summer, the abscission layer was identified to be prevented from full development by the auxin and therefore restricts the connection of the leaves to the alleged circulatory system of the tree (University of Wisconsin-Madison). Then, as explicitly noted, during fall, â€Å"cooler and shorter days trigger an end to auxin production, allowing the abscission layer to grow and cut off the circulation of water, nutrients and sugar to the leaves. When this happens, chlorophyll disintegrates rapidly, letting carotene shine through as the yellow in maple, aspe n and birch leaves† (University of Wisconsin-Madison par. 4). The roles of other environmental factors were further explained in the article published by The United States National Arboretum. Accordingly, â€Å"temperature, sunlight, and soil moisture greatly influence the quality of the fall foliage display† (The United States National Arboretum par. 8). Likewise, at its simplest narrative structure, Schwartz added that â€Å"leaves at the top and outer edges of a canopy usually have far brighter colour than the leaves that get less intense sunlight† (par. 13). Thus, the position of the leaves, the exposure to sunlight, the location and kind of trees all contribute to disparities in pigmentation and colours. The reasons why changes in colours are likewise different ensue from masking of pigments in leaves. As indicated: â€Å"Chlorophyll normally masks the yellow pigments known as xanthophylls and the orange pigments called carotenoids — both then become visible when the green chlorophyll is gone. These colors are present in the leaf throughout the growing season. Red and purple pigments come from anthocyanins. In the fall anthocyanins are manufactured from the sugars that are trapped in the leaf. In most plants anthocyanins are typically not present during the growing season† (The United States National Arboretum par. 6) Applications The change in colours of leaves during autumn affect people in terms of influencing emotions through the different colours that

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