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Walk into the forest.

Forests are biomes composed of a large number of organisms with trees as the main body. Forests contain abundant resources, which can be divided into two categories: biological resources and non-biological resources according to their natural attributes. Among them, biological resources can be divided into three categories: plant resources, animal resources and microbial resources.

Plant resources include forest resources (trees, shrubs and bamboo) and non-forest resources (algae, lichens, mosses, ferns and other seed plants, etc.); Animal resources mainly include mammals, reptiles, forest insects, birds and fish. Microbial resources mainly include various fungi, mycoplasma, chlamydia, etc. Abiotic resources mainly refer to the resources such as forest land soil and water that support forest organisms. It can be seen that the forest is a rich and colorful resource pool on the earth, and its main part, that is, the biological resources of the forest, is a renewable resource that can be used sustainably.

Forest resources are the basic resources on which human beings depend. At the same time, forests also have the ecological value of maintaining life on earth and improving the living environment of human beings.

Forests provide a steady stream of timber products and forest by-products to humans. Timber products mainly include logs, sawn timber, pulp timber, man-made panels, etc.; Forest by-products mainly include various products provided by forest animals and microorganisms. Providing these products to humans is undoubtedly an important function of forests.

Forests are the main regulators of ecological balance. Forests can convert solar energy into chemical energy and inorganic matter into organic matter, which is an important link for the exchange of matter and energy between living and non-living things, and plays a pivotal and leveraged role in maintaining the overall function of the ecosystem. It can be said that there is no ecological balance without forests.

Forests are effective in conserving water and preventing soil erosion. With a large canopy, deep leaf litter and well-developed root system, forests can play a good role in water storage and soil conservation and reduce surface erosion. It is estimated that 50,000 acres of forest can store about 1 million cubic meters of water.

In areas where forests are destroyed or non-forested, soil erosion is severe, and many rivers and water conservancy facilities are constantly silted up, often causing flooding.

Forests are effective in protecting biodiversity. More than half of the 500,300 million species on Earth now live and thrive in forests.

Forests can effectively mitigate the "greenhouse effect". Due to the massive use of fossil fuels by modern humans, the concentration of greenhouse gases such as carbon dioxide and methane in the atmosphere has been rising, causing the "greenhouse effect" on the earth. On average, 20 40 tonnes of carbon dioxide per hectare of forest can be absorbed per year, and 15 30 tonnes of oxygen are released.

According to relevant expert research, one hectare of forest can attract more than 700 kilograms of carbon dioxide per year on average, which can reduce the harm of industrial acid rain; The forest belt next to the road in the city can block sand and dust, and the dust retention rate is as high as 70% to 90%. At the same time, the forest belt also has the effect of reducing noise, and the noise can be reduced by 6 8 decibels through the 30-meter-wide forest belt.

Forests can produce direct economic benefits, and at the same time have huge ecological and environmental effects, which cannot be replaced by anything else.

The cicada song forest is more quiet, the birdsong mountain is more secluded, which poem comes from.

Students, I would like to introduce you to a fruit, and that is strawberries.

Strawberry, also called cranberry, ground berry, etc., its appearance is heart-shaped, delicious and red tender, the flesh is juicy, sweet and sour, the fragrance is rich, not only the color but also the pleasant aroma that the general fruit does not have, it is a rare color, fragrance and taste in the fruit, so it is often praised as the "queen of fruits".

The carotene contained in strawberries is an important substance for the synthesis of fiber A, which has the effect of brightening the eyes and nourishing the liver. It also contains pectin and is rich in dietary fiber, which can aid digestion. Strawberries have a certain tonic and conditioning effect on the gastrointestinal tract and anemia.

In addition to preventing scurvy, strawberries also have a good effect on the prevention and treatment of arteriosclerosis and coronary heart disease. Strawberry is a plant rich in tannins, which can adsorb and prevent the absorption of carcinogenic chemicals in the body, and has a cancer prevention effect. According to research, women often eat strawberries, which have a health care effect on ** and hair.

Strawberries are known as the "magic fruit" in Germany. Strawberries can also be ** because it contains a substance called aspartic acid, which naturally and gently removes "slag" from the body. According to Chinese medicine, strawberries are cool and sour, which has the effects of moistening the lungs, clearing heat and cooling the blood, strengthening the spleen and relieving hangover.

It has been determined that every 100 grams of strawberry pulp contains 8 to 9 grams of sugar, protein to grams, and 50 to 100 milligrams of vitamin C, which is 7 to 10 times higher than that of apples and grapes. Its content of malic acid, citric acid, vitamin B1, vitamin B12, carotene, calcium, phosphorus and iron is also 3 to 4 times higher than that of apples, pears and grapes. It is not unreasonable for the Taiwanese to call strawberries "living vitamin pills" and the Germans to hail strawberries as "miracle fruits".

When buying strawberries, it is better to have bright color, shiny, large particles and strong fragrance. It must be washed and sterilized before consumption. First of all, the leaves are removed, rinsed with water, then put in a clean container, the potassium permanganate is diluted at a ratio of 1 5000, the strawberries are soaked in the disinfectant solution for 5 to 10 minutes, and can also be replaced by table salt solution, and finally soaked in cool boiled water for 1 to 2 minutes before eating.

Use 500 grams of strawberries, add a little sugar and 100 ml of frozen soda, stir into juice and drink, it is said to be effective in removing blisters.

The nutrients of strawberries are easy to be digested and absorbed by the human body, and if you eat more, you will not get cold or get angry, so it is a healthy food suitable for all ages.