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Why do the green leaves turn yellow and fall off in autumn? Originally, it was thought that it was the result of the dry autumn and the loss of moisture in the leaves. But in previous years, scientists have discovered that the discoloration of leaves is linked to changes in certain hormones and chemicals.
In early autumn, the hormone abscisic acid and other substances accumulate in the leaves, and the leaves begin to change color, and the leaves return useful materials such as chlorophyll, water, nitrogen, phosphorus, protein and carbohydrates to the trunk and roots, waiting for them to wither and die. At the same time, a group of special cells in the leaf peduncle also begin to become fragile, so that in case of wind and rain, they can easily break off, and the leaves fall all over the ground.
Botanists point out that the color of the leaves in autumn is sometimes dark and sometimes light, depending on the amount of rainfall or snowfall. In dry years, the color of the leaves does not change too much, and the leaves fall earlier, which is to retain more moisture for the trees. Storing nutrients, keeping more water, and falling leaves are a means for trees to "lose their pawns and protect their cars".
In this way, it is really unnecessary for some literati and inkmen to complain when they see the fallen leaves.
Some green leaves turn red when the weather is cool. Beijingers will go to Xiangshan to see the red leaves in autumn, and Nanjing people also like to go to Qixia Mountain to enjoy the beautiful scenery of "ten thousand mountains are red". Maple trees, maple trees, black trees, cochinese, persimmon trees, etc., will become fiery red before and after the frost falls.
Frost leaves red in February flowers". They are embellished with golden autumn, attracting countless tourists and decorating the country more delicately.
Whether it is yellow or red leaves, under the cold winter wind, the leaves of deciduous trees eventually fall off, leaving only bare trunks. Then, in the tropical areas where the seasons are always summer, don't the leaves need to fall? No.
Tropical trees also lose their leaves. However, they always lose their leaves during the dry season. Take Guangdong, Yunnan, Hainan and other places in China as an example, many trees only lose their leaves in February and March every year.
The saying "a leaf knows autumn" does not apply in these places; "When a leaf falls, you know the autumn of the world", it is even more inconsistent with the reality of nature.
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When autumn comes, the color of the leaves will turn yellow because the chlorophyll is destroyed and the yellow leaf pigment comes out.
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Because when autumn comes, the temperature plummets and it will be very cold, and the water vapor in the air will decrease at this time, which will affect the chlorophyll, so the leaves will change color.
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When the leaves stop providing "food" for the tree, its color degrades from green to yellow, orange, red, and sometimes even purple until it turns brown and dies.
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1. Flame Euonymus.
Euonymus is a deciduous shrub with dark green leaves, but in autumn the leaves turn flame-red, and it has many branches, and the plant grows neatly, but slowly.
Flame Euonymus is a particularly well-maintained ornamental shrub plant, suitable for planting in the yard, it is extremely adaptable to the environment, and has good cold tolerance. In the summer, the flame euonymus will have a layer of oil on its surface and smell like lemon.
2. Suac. Lacquer is a kind of deciduous tree, it is more common in the northern region of our country, lacquer is also a kind of ornamental plant that will turn red leaves in autumn, it is easy to become a wild plant in the wild, few people will buy this kind of tree to plant, generally in the park, or relatively large courtyards to see, some grow on the side of the road and on the hillside.
3. Maple. The maple tree is a particularly common ornamental shrub and is particularly popular for growing as a shrub plant in the yard or as a small bonsai in a pot, and the leaves turn red, brown, and yellow in the fall.
4. Oak tree. Oak trees are ancient trees with a very long history, some can grow up to more than 100 years, so the trunk is particularly thick, and in recent years, there are many oak trees that have grown into shrubs, but they are more popular, and they are suitable for planting in the garden and are also good for ornamentation.
The leaves of the oak tree turn red in autumn. If you want to plant it in the yard, there must be a particularly large space, there is not enough space around the environment is not ventilated, it is impossible to grow well, and you must add some basic bark, perlite, etc. every year to ensure that the fertilizer and water are sufficient, so that its root system will grow deeper.
5. Five-leaf ground brocade.
Five-leaf brocade is a kind of creeper, can climb on the wall and fence to grow, some people also call it five-leaf ivy, the name is very many, it is a particularly easy to raise an ornamental plant, grow particularly fast, but also easy to become a wild plant.
The leaves of the five-leaf brocade will turn a beautiful red or orange in autumn, and in the wild, you can also see some trees climbing on the walls or trunks of the five-leaf brocade, which is easy to spread excessively.
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In autumn, most of the leaves will dry out, turn yellow, and then wither and fall.
In autumn, the temperature drops and the light time is shortened, which affects the absorption capacity of the root system and the photosynthesis of leaves, so it cannot meet the growth and development of trees.
When the temperature drops and the air is dry, the water in the leaves evaporates quickly, but the ability of the roots to absorb water has been greatly reduced, and the water and nutrients are insufficient.
In order to survive the tree, the junction of the petiole and the leaf stem forms an isolation layer, the leaves are cut off from the water **, coupled with the low temperature, the chlorophyll is destroyed, and lutein and so on begin to be active, so the leaves will turn from green to yellow and fall off, with the autumn wind back to the earth embrace.
In fact, lutein, which turns leaves yellow, and chlorophyll, which turns leaves orange and red, are present in the leaves from the day they grow, but they are masked by the green chlorophyll.
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The reason why the leaves turn yellow in autumn is different from the green color in spring is due to the change of seasons and the fall of leaves, which is determined by the growth characteristics of different plants.
Therefore, we should pay more attention to the observation at ordinary times, you can communicate and learn more with professional personnel, and it will be better to master more laws of plant changes.
1.Keep your profile down when communicating.
I'm right", this attitude will only lead to the deterioration of the communication relationship and make it impossible for the communication to continue. When communicating, it is best to keep your profile as low as possible, that is, to fully respect the opinions of the other party, and to express your opinions and opinions appropriately and not excessively. Even if you think that your statement is not wrong or there is a problem with the other party's opinion, you should first listen to the other party's words, different people have different ideas, the ability to express and understand is also different, there may be the other party's expression mistakes or their own understanding is biased, you should lower your posture and listen patiently.
2.Don't get emotional.
When communicating, it is important to keep a calm mind and not be emotional. Emotionally charged Fan Qing may make the communication stuck halfway and unable to get through, and even lead to the abandonment and failure of communication. If you feel particularly irritable and restless in the process of communication because of your emotions, you will have to stop communicating and wait for a period of time to calm down before you can continue to communicate, which will actually make all parties in the communication unhappy.
3.Abandon your self-esteem when communicating.
Needless self-esteem and pride can only become a stumbling block to communication.
Therefore, at the very least, you should give up your so-called self-esteem when communicating. Don't say "My self-esteem won't allow me to ......In that case, it will only make communication impossible.
4.Be open and honest with the person you're communicating with.
In the process of communication, it is very important to be honest with the person you communicate with, and there is no concealment, honesty is an important step for you to deepen the cooperative relationship through communication. First of all, you can make the other party believe in yourself through your own honesty, and then drive the other party to be honest with you, and then promote the smooth and happy communication.
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