Why do the red leaves of Xiangshan turn red

Every late autumn, the red leaves are in full swing and the scenery is colorful, which makes tourists linger. There are many famous natural scenic spots to watch red leaves in China, such as Xiangshan and Badachu in the western suburbs of Beijing, Tianping Mountain in Suzhou, Qixia Mountain in Nanjing and Yuelu Mountain in Changsha, which are all good places to watch red leaves.

In addition to chlorophyll, lutein, carrots and other pigments, plant leaves also contain a special pigment called anthocyanin, just like "chameleon". It is red in acidic solution. With the change of seasons, the temperature and sunshine increase or decrease correspondingly, and the main pigment components in leaves also change.

In autumn, with the decrease of temperature, the temperature difference between day and night increases and the light decreases, which is beneficial to the formation of anthocyanins. At this time, the leaf cell sap of maple and other red-leaf trees is acidic, and the whole leaf is red. Therefore, it was the weather conditions in autumn that dyed it red.

1986, Xiangshan Park was named as one of the new 16 scenic spots in Beijing by Beijing people. The green leaves of maple, cotinus coggygria, persimmon, torch tree, Parthenocissus tricuspidata and other plants gradually turned red under the stimulation of cold weather conditions, which painted a colorful picture of the late autumn in Beijing.

Why do the leaves of some plants change from green to red once a year? This is inextricably linked with meteorological conditions. The green color of leaves comes from chlorophyll, which contains a lot of chlorophyll, in addition to lutein, anthocyanin, sugar and other pigments and nutrients. After summer, the days become shorter, the temperature drops, plants also spend the peak period of the year, and the chlorophyll yield in leaves decreases.

It was destroyed as the weather became cold. Ginkgo biloba, poplar, osmanthus and other leaves lack chlorophyll, leaving lutein, the color of leaves turns yellow. In the hilly forest of Xiangshan Mountain, there are dense cotinus coggygria trees with leaves like small round fans, and a large number of five-fingered maple trees, cypress trees, lacquer trees and Chinese toon trees. When the late autumn season comes, the weather gets colder every day. In this suitable weather condition, anthocyanins in leaves will be exposed, making red very bright. Especially before and after the first frost solar term, the chlorophyll on the leaves of frost-damaged plants is further destroyed, and the sugar stored in the branches and leaves will also increase, making the leaves more and more red. According to the amount of anthocyanin and sugar, leaves can form different colors such as bright red, scarlet, scarlet and purple. Due to the different influences of topography, local climate and sunshine, the temperature decreases with the increase of mountain height, and the area and time of plant leaves turning red are also different. The top of the mountain is cold, so the red leaves turn earlier than those in the low-lying areas. Viewing time is earlier in the north than in the south. In Beijing, the viewing area of red leaves is very wide. From northwest to southeast, deep mountains, shallow mountains and plain areas have different degrees of change according to different altitudes and temperatures. The viewing period can last from late September to165438+1mid-October for nearly two months, especially when the cold front passes through, the temperature drops sharply, the sun rises, and the leaves are blue and red, which can be described as "the red leaves in the western hills are good."