This paper takes part in the series essay competition of “great science” of Recordunkown.
The earth is a beautiful life world. The reason why life can be born and continued on the earth is that the earth has a perfect ecosystem. In this ecosystem, plants occupy a very important position. Plants absorb carbon dioxide and release oxygen through photosynthesis, and most of the earth’s organisms need oxygen to survive.
At the same time, plants are also important natural purifiers, which can continuously absorb and purify the toxic gases and dust in the air, so as to provide a good ecological environment for the survival of organisms. In the plant ecosystem, the forest formed by tall trees is an important part. With the existence of forest, there are a large number of herbivorous animals.
Herbivores are the food of carnivores, and their prosperity directly determines the stability of the whole earth’s biological system. Therefore, forest area is an important indicator to measure whether the earth’s ecosystem is beautiful and stable. For the ecosystem, the more the forest area, the better.
But everything has two sides. The more the forest area, the better the stability of the ecosystem, and the more conducive to the survival and reproduction of animals. However, trees are also the most prone to fire. Once a forest fire occurs, it will have a serious impact on the surrounding ecological environment. If it is a particularly huge forest fire, it will also affect the global ecological environment.
With the rapid development of human industry, more and more carbon dioxide and greenhouse gases are emitted into the atmosphere, which leads to the increasing greenhouse effect and global temperature. With the increasing temperature of the earth, the probability of forest fire is becoming more and more frequent and higher. There are many forest fires all over the world every year. One of the most impressive is the Australian forest fire which happened in September last year.
As we all know, Australia’s virgin forest is world-famous, and its area is also very large. Moreover, Australia is a very hot and dry place, where forest fires are very easy to happen. In September 2019, the virgin forest here caught fire again. What many people did not expect was that the fire would be so serious this time.
It started burning in September 2019 for more than five months, and it was not until February this year that it was basically extinguished. Such a long time of forest fire naturally caused very serious losses, thousands of residents were forced to flee their homes. Australia’s forest fires have burned an area of 1.8 million hectares. In addition, more than 1400 kilometers of coastline are burning, from the northeast to Jiangsu, Zhejiang and Shanghai.
According to the World Wildlife Fund, about 1.25 billion wild animals died directly or indirectly in the forest fire. The consequences of the fire are very serious, not only affected the ecological environment of Australia, but also affected the whole ecological environment of the earth.
After five months of hard work, the fire that shocked the world was finally put out. Now nine months have passed, and the virgin forest, which was desolate after the initial fire, is beginning to glow green. The recovery ability of plants is far beyond our imagination. Wild fire can’t be burned out and spring breeze can blow again. This is the true portrayal of the tenacious biological ability of plants.
What we see in Australia’s primeval forests today is a growing number of trees, and more and more trees are green. But when scientists see this green, they are not happy. Why? The reason is that eucalyptus, which is the first to recover, let us see the beginning of the next tragedy.
Eucalyptus is known as Australia’s “national tree”. In the forest that accounts for 20% of Australia’s land area, the planting area of Eucalyptus accounts for about 80% of the total forest area. Because eucalyptus bark is rich in eucalyptus oil, they fall off and accumulate at the root. When the temperature reaches 40 ℃, they will spontaneously ignite, which is very easy to cause forest fires. The main culprit of the Australian fire is Eucalyptus.
We often say that fire and water are merciless, especially fire. Plants are the most afraid. Basically, no plant likes fire. But Eucalyptus is different. It likes fire very much. Why? Eucalyptus is a kind of special tree. After thousands of years of evolution, it has evolved the ability of not afraid of fire.
Eucalyptus generally has a straight and tall trunk, branches only grow at the top of the tree, when the mountain fire occurs, the branches and leaves of other plants will be severely roasted by the mountain fire, and the high crown of Eucalyptus can prevent the fire from climbing up to a certain extent. In addition, eucalyptus has very thick bark, which can withstand the fire.
Eucalyptus has a very strong demand for fire, because its seeds are wrapped in a very thick shell, which needs fire to break, and then take root. From the perspective of life reproduction, Eucalyptus likes fire very much, which is easy to understand.
If Eucalyptus wants to make its family prosperous, it must rely on the power of fire. In order to get the favor of fire, eucalyptus has evolved to be very flammable. Its leaves are rich in oil plants. And the higher the ambient temperature, the more oil plants it secretes, which makes it easier to catch fire.
Eucalyptus is not welcomed by human beings. In many areas of China, eucalyptus is called immoral tree. It is not afraid of fire, but actively ignites the fire. After the fire, all other plants and trees are burned out. However, Eucalyptus can recover quickly after the fire because of its thick bark and undamaged internal nutrient pipeline.
Therefore, after the Australian forest fire, Eucalyptus was the first to recover in large quantities, and its seed shell was also broken by the fire, which was conducive to the germination of new Eucalyptus. Because Eucalyptus is very tall, when it recovers and grows up, the growth of other trees and plants will be greatly affected.
Therefore, every time there is a big fire in Australian forest, the proportion of Eucalyptus will increase by one point. Now it occupies 80% of the forest area. After this big fire. After the forest recovers again, the area of Eucalyptus is likely to exceed 80%. The more eucalyptus trees there are, the more likely there will be another fire, which is a vicious circle.
Although we all know that eucalyptus is easy to cause forest fires, but we have no way to change it. Some people may say that we can cut down all eucalyptus trees in Australian forests and plant other trees?
This method looks good, but it is very difficult to implement. You know, the Amazon rainforest is a virgin forest that has existed for tens of millions of years, and its area is very vast. If we want to remove the eucalyptus, not to mention how much manpower and material resources we need to pay, this kind of man-made destruction and removal will virtually destroy the whole forest system.
Once there are problems in Australia’s virgin forest system, the ecological impact on the whole earth will be very large. It may lead to a series of uncontrollable factors. Therefore, we have no way to remove and replace Eucalyptus in the forest, we can only take fire prevention measures. What is more important is to strengthen the scale and capacity of fire fighting.
Australia has a vast forest area and is prone to fire, but its fire fighting ability is very weak. There are less than 3000 professional firefighters in the whole country, and forest fires mainly rely on volunteers. The number of rescuers is just a drop in the bucket for such a raging fire, so it took five months for the fire to go out.
With the increasing global warming, we can foresee that forest fires like last year will continue to occur in the future. The stability of the earth’s ecology and human ecology cannot be separated from these forests. We can only increase the forest area, but not reduce it. But with the increase of forest area, the probability of fire will increase. We should not only strengthen the ability of fire rescue, but also develop more powerful fire equipment.
Technology can create unlimited possibilities, and we can also apply technology to make fire no longer a threat. As long as there are more powerful fire fighting equipment and technology, forest fires like Australia can be put out quickly, thus greatly reducing losses. If we protect the forest, we will also protect the earth’s ecology and the home for human survival.