Foreign media said the Washington-based World Resources Institute reported that in 2014 the global loss of more than 18 million hectares of forest land, equivalent to two Portuguese land area.
The report, based on data provided by the University of Maryland and Google, said the tropical countries were the most affected, accounting for 9.9 million hectares, more than half of the lost forest area, according to the report.
The report shows that the global forest loss area in 2014 is the largest since 2001. The data show that the Southeast Asian Mekong River Basin, South America's Greater Chaco region (including Paraguay, Argentina and Bolivia), West Africa and Madagascar has become a new priority area.
According to the report, according to the country, in 2014 the forest is facing the fastest growing countries in Cambodia, followed by Sierra Leone, Madagascar, Uruguay, Paraguay, Liberia, Guinea, Guinea-Bissau, Vietnam and Malaysia.
The report shows a gradual increase in demand for rubber and palm oil, as well as the expansion of soybean acreage, farms and other agricultural products, has led to a reduction in forest area in some unexpected areas.
The report also emphasizes that Brazil, the world's largest tropical rainforest, has fallen by 70 percent in the past 10 years, and is considered a success story in forest land protection. However, the report also noted that Brazil's forest loss rate increased significantly in 2014, which may be affected by changes in the prices of certain consumer products.
The role of the forest
Green plants are producers of carbon dioxide consumers and oxygen. Usually one hectare of broad-leaved forest can consume 1000 kilograms of carbon dioxide a day, the release of 730 kilograms of oxygen.
Experiments show that the forest in the low concentration range, the absorption of various toxic gases, so that the pollution of the environment to be purified.
For example, one hectare of cedar trees can absorb 60 kg of sulfur dioxide per month. Canna, rose, clove, chrysanthemum and ginkgo, acacia can also absorb sulfur dioxide.
The ability of the forest to adsorb dust is 75 times greater than the bare earth. One hectare of beech wood, within a year of dust is as much as 68 tons.
According to the survey, the downtown air bacteria, more than 7 times more than the green area. One reason is that some plants can secrete strong antibiotics, such as orange, lemon, chopper, black walnut, French sycamore and other plants, have a strong bactericidal force.
Into a piece of trees can absorb, block the sound, so a large number of trees in the city can effectively reduce the noise.
In addition, the forest in the conservation of water, to maintain soil and water, wind and sand control, climate regulation, etc., have played a very important role.
The harm of forest reduction：
一.The ability to reduce air purification. With the rapid development of industrial and mining enterprises and human life with the sharp increase in fossil fuels, contaminated air mixed with a certain amount of harmful gases, threatening the human, which is widely distributed, harmful harmful gases. Where creatures have the ability to absorb sulfur dioxide, but the absorption rate and ability are different. Plant leaves are large and absorb more sulfur dioxide than other species. According to the determination of forest seed air sulfur dioxide than the open to 15-50% less. If the high temperature and humidity in the summer, with the strong physiological activities of trees, the forest will absorb the speed of sulfur dioxide will be accelerated. Relative humidity above 85%, the rate of absorption of sulfur dioxide in forests is 5-10 times the relative humidity of 15 times.
二.The role of natural epidemic prevention decline. Trees can secrete a very strong lethal killer, kill the bacteria and microorganisms in the air, have a certain health effects on humans. Some people have different environments, cubic meters of airborne bacteria were measured in the crowd flow of the park for 1000, street downtown area of 3-4 million, and only 55 in the forest. In addition, the number of fungi secreted by trees is considerable. For example, a hectare of cypress Berlin can secrete 30 kilograms of fungicide every day, can kill diphtheria, tuberculosis, dysentery and other bacteria.
三.The oxygen content decreased. Oxygen is the basic condition of human life, the human body every day to breathe oxygen, discharge of carbon dioxide. A healthy person three or two days do not eat or drink will not be fatal, and a few minutes of hypoxia will die, it is well known common sense. Literature records, a person to survive, every day need to inhale 0.8 kg of oxygen, discharge 0.9 kg of carbon dioxide. Forests in the growth process to absorb a lot of carbon dioxide, release oxygen. According to the study, trees absorb 44 grams of carbon dioxide, each can absorb 32 grams of oxygen; trees through photosynthesis to produce a gram of glucose, can consume 2500 liters of air contained in all the carbon dioxide. According to the theoretical calculation, the forest for each growth of a cubic meter of wood, can absorb about 850 kilograms of carbon dioxide in the atmosphere. If the tree growing season, a hectare of broad-leaved forest, every day to absorb a ton of carbon dioxide, manufacturing production of 750 kg of oxygen. Facts, 10 square meters of forest or 25 square meters of grass will be able to breathe a carbon dioxide all the absorption, supply the required oxygen. It is true that trees have the ability to absorb carbon dioxide at night, but because of the large amount of carbon dioxide absorbed during the day, it is almost 20 times that of the night, compared to the nighttime side effects. In the world, forest greenbelt deals nearly 100 billion tons of carbon dioxide per year for the human body, providing 60% clean oxygen for the air while absorbing suspended particulates in the atmosphere, greatly improving air quality, and reducing greenhouse gases , To reduce the thermal effect.
八.Animals are threatened, but also the growth of many types of plants, the earth is the most active areas of biological reproduction. So the forest protects the biodiversity resources; and whether it is in the periphery of the city or in the suburbs, the forest is the high value of the natural landscape resources.
As a result of the large consumption of wood resources in the forest, the area of the forest on the planet is decreasing year by year, which raises a wide range of environmental problems such as drought and dryness, climate warming, reduction of plant and animal resources, soil erosion, dust storms and air Pollution and so on. Therefore, the value of the forest to the environment and ecology is much higher than it provides the value of wood.
Therefore, afforestation, expansion of forest area, increase forest resources, is related to economic efficiency, social benefits, environmental benefits and human survival of the event.