For a long time, foreign scholars have doubted whether there is a real tropical rainforest in China, the main basis of which is that China's tropical plants, especially dipterocarp, are very poor.
Dipterocarp plants are considered to be characteristic tree species in the Asian tropical rainforest, and forests with dipterocarp species can be called tropical rainforests; conversely, forests without dipterocarp tree species are difficult to identify as tropical rainforests.
There are about 580 species of plants in 15 genera, mainly produced in Indonesia and Malaysia, India, Myanmar, Vietnam, the Malay Peninsula to Java and other places.
In order to find out whether there is a tropical rainforest in China, if there is a tropical rainforest, what are the constituent plants, etc., Chinese scholars have conducted a full study of the tropical nature of China's flora after years of in-depth investigation, and finally confirmed: China's tropical fauna plant composition is more than 1390 genera, accounting for 50.3% of the national genus, of which the southeast Asian tropical fauna components account for 21%; there are 5 genera, 11 species and 2 varieties of dipterocarp plants distributed in China. This means that China has tropical rainforests. Tokyo dipterocarp is one of the main dipterocarp plants in China's tropical rainforest.
"Big Chicken Feather Tree"
Tokyo Diptcrocarpusretusus, also known as North Vietnamese dipterocarpusretus, is a plant of the genus Dipterocarpusretus in the family Dipcrocarpusretus, also known as North Vietnamese dipterocarpus. In Latin, its genus name Dipterocarpus means fruit with two long wings, and retusus means blunt, slightly concave. Taken together, the terms refer to The Tokyo dipterocarp is characterized by the rounding of the apex of the two long fruit wings. Because it resembles the shuttlecock we use for sports and games, it is also known as the "big chicken feather shuttlecock tree".
Tokyo dipterocarp is a large evergreen tree with a height of more than 40 meters and a chest diameter of 1 meter; the trunk is straight, with white aromatic resin, and the bark is gray and white. The leaves are oval or broadly oval, rounded at the apex, pointed, wedge-shaped or broadly wedge-shaped at the base, and covered with fine hairs on the lower veins. The inflorescence is axillary, with 2 to 5 flowers, 5 petals, spiral-like arrangement, and the outer part is densely covered with scaly hairs. The fruit is ovate, densely covered with short gray hairs, and the two enlarged wings are bright red. The flowering period is from May to July, and the fruiting period is November.
In China, Tokyo diplodocus is only grown in the estuary of Yunnan River, Pingbian, Jinping County, China-Vietnam, China-Myanmar border area, 100 to 1100 meters above sea level in the tropical northern edge of the rainforest, usually distributed in the southeast monsoon in front of the mountain deep valley bottom. It is dark and damp, frost-free all year round, and there are many still winds, which belong to the tropical monsoon climate with high temperature and high humidity, and the natural fertility of the soil is high.
The value of scientific research application is high
In the study of tropical flora in Southeast Asia, dipterocarp is one of the families that researchers pay the most attention to, not only because it is a landmark tree species in the tropical rainforest, but also as an ancient plant.
The geographical location and topography of China's tropical regions are very special, although it has experienced Quaternary glaciers, it still preserves an extremely rich paleotropical plant area music composition, and the natural distribution of dipterocarp species in tropical areas of China can be considered as the northern edge component of this family in Southeast Asia.
Due to the tropical nature of dipterocarp plants, some scholars often take whether there is a large distribution of dipterocarp plants in Southeast Asia as one of the indicators to measure whether the region belongs to the tropics. Other scholars have used the upper limit of the distribution of plants in this family at altitude as an approximate dividing line between flat tropical rainforests and montane rainforests.
It is precisely because of the above factors that the dipterocarp family and the Tokyo dipterocarp among them are of great value in studying the tropical flora and germplasm resource conservation of China.
In addition to the value of scientific research, Tokyo dragon brain incense also has great application value in industry and other aspects.
As a large tree in the upper layer of the tropical rainforest, the trunk of the Tokyo dipterocarp tree is straight and tall, the nodes are few, the branch height is very high, usually above 20 meters, the yield is high, the texture is straight, the strength is large, the pressure resistance, the corrosion resistance and insect resistance, the material is excellent, in the Yunnan estuary is an excellent material for shipbuilding, known as the "big leaf boat board tree". In addition, Tokyo dipterocarp can also be used in the production and living areas, and is a rare and precious large-diameter wood species.
Because the wood contains tree wax, it can be cut in the trunk of the Tokyo dragon's brain or distilled from wood to produce volatile oil for the paint, antiseptic and pharmaceutical industries, so it is also called "Vietnamese oil tree".
"Internal and external troubles" are endangered
Deforestation and difficulties in natural regeneration are the main reasons why Tokyo's dipterocarp is endangered.
Due to the superior water and heat conditions of the distribution of Tokyo diplodocus, those places with gentle slopes and deep soil layers have been mostly reclaimed into rubber plantations or used to plant other cash crops, resulting in a continuous reduction in forest area, especially the destruction of forests below 1000 meters above sea level, and the deterioration of the ecological environment in the production area, which seriously threatens the survival of the tree species. In addition, the high utilization value of Tokyo's dipterocarp wood is more vulnerable to vandalism. At present, it can only be seen on narrow and steep slopes or in wet remnants of dense forests such as river valleys, streams, and lime mountains.
In addition to external interference factors, the original population of Tokyo dipterocarp is small, and the living environment is special, which increases the difficulty of updating the tree species.
More importantly, the characteristics of dipterocarp plants in spread are at a significant disadvantage compared with other tropical plants: although the fruits of this family have fruit wings, they are generally larger, spread by wind or water, and it is difficult to spread far; its seeds usually do not have endosperm, and are rich in oil, often eaten by insects and animals; seeds do not have a dormant period, often begin to germinate before landing, mature and landed, in a humid and hot forest environment, it is easy to lose germination, is a famous short-lived seed.
In its distribution area, although the Pingbian Dadaoshan, Jinping Watershed, Huanglian Mountain and other nature reserves have been established. However, due to the scattered and scattered distribution, fragile ecology, and small number of existing plants, it is difficult to protect plants such as Tokyo diplodocus.
In the Plant Protection Ordinance issued, Tokyo diplodocus is listed as a First Class Protected Wild Plant. According to the Threatened Plant Grading System published by the Union for the Conservation of Nature and Natural Resources (IUCN) and adopted internationally, Tokyo Diplodocus is classified as a "Critically Endangered Species (CR)".