The cold knowledge behind the tallest tree in China
Zhang Tiankan
Recently, extremely tall trees have been discovered frequently in China.
The investigation team of the Institute of Botany of the Chinese Academy of Sciences discovered a large virgin forest of Yunnan Huangguo fir in Zayu County, Tibet. The tallest one is 83.2 meters high, setting a new record for the tallest tree in China.
This is the discovery of the second Qinghai-Tibet Plateau scientific expedition "Forest and Shrub Ecosystem and Resource Management".
Previously, the Peking University research team also discovered a Bhutan pine with a height of 76.8 meters in Medog County, Tibet.
Today, let's talk about the biology behind these "tallest trees".
The tallest trees grow deep in nature
The tallest tree in China previously discovered is a bald fir with a height of 81 to 82 meters in Taiwan, China.
In October 2021, a bald cedar with a height of 72 meters in the Gaoligong Mountain Reserve in Yunnan measured by the "Wild China" team was the tallest tree previously measured in mainland China.
Looking around the world, the height of the tallest tree is even higher.
In the late 19th century, the almond eucalyptus in the Australian mainland was once considered to be the tallest tree in the world. It is said that the tallest almond eucalyptus was discovered in 1871 on the banks of the Water River, with a height of 132.6 meters. The surveyor was an ordinary person. forestry workers, but this claim is not universally recognized.
A 114.3-meter-high almond eucalyptus discovered in 1881 has also won the title of the world's tallest tree.
The tallest tree in the world that is often mentioned today is the redwood.
Sequoia is native to the coast of California, USA, and is a large tree with a height of 100 meters.
In 2006, a redwood tree with a height of 116 meters was discovered in the Redwood Forest National Park in the United States, and was named "Hyberron God" by the staff.
Hyperion is one of the Twelve Titans in Greek mythology, which means "those who travel through the sky".
In 2014, geographer Boyd of the University of Nottingham, UK, and colleagues conducted an aerial mapping of the Danum Valley Reserve in the Malaysian state of Sabah.
In this survey, they found a towering tree and named it "Menara", which means "tower" in Malay, which is a double tree of yellow salamander.
At the time, they did not know the height of the tree.
It wasn't until 2019 that precise measurements of the tree were made, which confirmed the tree's height to be 100.8 meters.
Researchers believe that the "tower" may be the tallest tree in Asia today.
The tallest trees in the world are mainly distributed in the Amazon forests of the United States, Malaysia, Brazil and other places, with a height of more than 100 meters.
Including the tallest tree in China, these extremely tall trees grow deep in nature undisturbed and unaffected by humans.
Being tall is a need for survival competition
The research team who discovered the "Pagoda" of the Huang Soluo double tree in Sabah, Malaysia, through in-depth research, found that the weight of the "Pagoda", excluding the roots, is as high as 81.5 tons, which is equivalent to the weight of 13 African savannah elephants.
Moreover, even when the tree grows to 255 meters, it can still support its own weight.
Therefore, it will take a long time for the "tower" to collapse under its own weight.
Moreover, there are other equally tall trees in this area of Sabah, such as the 89.5-meter and 97-meter yellow salsa trees, and the 94.1-meter-high salsa trees, plus Dipterocarpaceae trees, there are more than 90 local trees. There are 50 trees of rice.
The reason why the local trees grow so high is first of all the need for survival competition, but also determined by the geographical location.
Saloshuang and other Dipterocarpaceae trees can grow so high partly to compete for sunlight, water and nutrients, and partly to use the wind blowing across the tree tops to spread their seeds so that their offspring can go further. multiply.
This principle is like dandelions use the wind to disperse their seeds, so these tall trees can be regarded as extremely large dandelions.
At the same time, there are so many tall trees in the area because of its geographical environment.
Sabah is also known as the "Land of the Wind", but Sabah is just outside the typhoon belt and is a buffer zone between strong winds and the northwestern region of Malaysia.
And, unlike the Congo and Amazon rainforests, Sabah is on an island rather than landlocked, which means Sabah is less exposed to storms.
Sabah is actually located in the leeward area of the valley, sheltered from the strong winds that blow through here, so the trees grow tall without being blown by the strong winds.
The 'king of trees' has an amazing amount of carbon storage
Tall trees mean strong competitiveness, and if there are more tall trees and "tree kings" in a forest, it proves that the environmental ecosystem is rich in productivity.
The so-called productivity of an ecosystem refers to the total amount of organic matter or organisms produced per unit area or volume within a certain period of time, which can be expressed in quantity, weight or energy.
The high productivity of an ecosystem means that it has a high ability to accumulate carbon and has the potential to produce and maintain a large number of organisms, so that more tall trees can be bred.
The place that can breed the "tree king" is of course an environment with better original ecology and higher productivity.
Sabah in Malaysia is not only productive, but also has good groundwater resources.
Similar to Sabah is the Amazon rainforest in Brazil.
In 2019, when Brazilian researchers examined satellite imagery from Brazil's National Institute for Space Research, they found a cluster of trees 70 to 80 meters tall in the Amazon rainforest.
Most of these large trees are located on the edge of the river, most of which are over 70 meters high and belong to the Amazonian bean (a type of sandalwood).
Later, the scientific research team conducted a field survey and measured that the tallest tree is 88.5 meters high, and the age of this group of trees is 400 to 600 years old.
The trees are remote and avoid the hurricane's path.
The presence of tall trees in the Amazon rainforest is a productivity in itself.
The Amazon rainforest and other tropical forests store 90 billion to 140 billion tons of carbon, which helps stabilize the world's climate.
The massive size of tall trees can accumulate enormous amounts of biomass and carbon storage.
In general, the carbon storage of each large tree is equivalent to hundreds of ordinary trees, and the "king of trees" is even more so. The carbon storage of one large tree is as much as 1 hectare of forest (about 160 tons).
The Amazon rainforest alone accounts for 1/10 of all biomass on Earth.
According to the findings of Brazil's national research agency, the Amazonas Institute, a tree with a diameter of 10 meters emits more than 300 liters of water into the atmosphere every day in the form of gas, more than twice the daily water consumption of a Brazilian.
And trees that are more than 70 meters high emit dozens of times more water into the atmosphere every day than small trees that are less than 10 meters high.
In addition, the Amazon rainforest provides 1/5 of the fresh water that flows into the world's oceans.
Significant for maintaining biodiversity
Considerable research has shown that forests with higher tree growth have higher biodiversity.
A research team in the United States conducted research on more than 80,000 small forest plots in the United States, measured tree height and species composition per 600 square meters of land, and then combined the data in nearly 1,000 square kilometers of grid land to arrive at the result. The highest tree height is positively correlated with the diversity of tree species.
Researchers from the Chinese Academy of Forestry found that tree height is an important factor affecting biodiversity. The taller the tree, the more moss that grows and adsorbs, which is more conducive to the survival of other organisms.
The reason is that the tree height restricts the microclimate change of the entire vertical gradient from the top of the tree to the ground, and this microclimate change can make the epiphytic bryophytes find different areas for their own survival, making the species more diverse.
Taking Medog as an example, in the mountain rainforest of Bhutan pine with a height of 76.8 meters found in Medog County, Tibet, there is also the densest 70-meter+ giant tree community in China, which shows that tall trees are mixed with other tree species. Formed the rich biodiversity of Medog.
The Brahmaputra Grand Canyon, which belongs to Medog County, is 504.6 kilometers long and has a drop of more than 7,000 meters. This area is one of the 34 biodiversity hotspots in the world.
In terms of topography, there are plateau meadows commonly seen in Tibet, mountains covered by tall cedar trees in the subarctic zone, and rainforests overgrown with giant banana trees.
In addition, Medog County has complex landforms, large altitude differences, diverse habitat types, sufficient heat, and abundant rainfall. It has almost all types of vegetation from tropical rain forests to high-cold rock beaches, and has nurtured almost all types of terrestrial vegetation from tropical to frigid zones. It is responsible for 65% of the known higher plant species on the Qinghai-Tibet Plateau.
These rich flora and tall cedar trees attract many animals and become the habitat of many endangered animals, such as clouded leopard, snow leopard and red goral, and the only confirmed habitat of Bengal tiger in China.
Thanks to the biological resources of the forest, more new species have been discovered in Medog County and the Brahmaputra Grand Canyon.
For example, the newly discovered Medog stinging frog was discovered in 2005; the Medog stinking frog was newly discovered in 2008; a new primate species, the white-cheeked macaque, was newly discovered in 2015; New genus and new species - Medog Mole of the genus Alpine Mole, etc.; Newly discovered Zhou's horned toad and Ye's horned toad in 2020.
In the newly released list of national key protected animals, there are nearly 30 species of national key protected animals recorded in Medog.
Among them, Medog Mole lives in oak bushes at an altitude of 2400 to 3700 meters, and is only produced in Gedang and Damu Townships of Medog.
This shows that tall trees and multi-species forests are of great significance to the maintenance of biodiversity.
Further reading
How is the "height" of the tallest tree measured?
In fact, there are both modern technology and primitive methods to measure the height of trees.
For example, when measuring the tallest tree "tower" in Asia in 2019, the most primitive "tree climbing" method was used. The local climber Jamie climbed to the top of the tree and put the measuring ruler on the top of the tree. After reaching the ground, it was confirmed that the height of the tree was 100.8 meters.
In October 2021, the "Wild China" team measured a 72-meter bald fir in Yunnan's Gaoligong Mountain Reserve, also using the "tree climbing" method.
This time, the measurement of the height of 83.2 meters of yellow fruit fir and 76.8 meters of Bhutan pine used the method of backpack lidar and drone.
The lidar method uses lasers to measure the distance between two points; the drone method uses the drone to fly to a place where the top of the tree canopy is flush, drop the sling, and then measure the length of the sling.