poplar

poplar

This data is reviewed by the project of data compilation and application of Science Encyclopedia of science popularization in China.

Poplar (Latin name: Populus L.) is a plant of Populus genus. There are about 100 species in the whole genus. There are about 62 species (including 6 hybrids) in China. Among them, 57 species are distributed in China, and about 4 species are introduced. In addition, there are many varieties, forms and introduced strains.

Populus classification system can be divided into five groups: tacanahaca, Leuce, Aigeiros, turanga and leucoides. Trunk usually straight; bark smooth or longitudinal, often gray white. Mainly distributed in Central China, North China, northwest, northeast and other vast areas.

History of Botany

Name source

According to the explanation of "Yang" in ShuoWenJieZi, poplar grows rapidly and is the first tree to form shading effect. Therefore, the right part of "Yang" in the traditional style of "Yang" is taken from "Yang" in the traditional style of "Yang".

There is another saying: poplar grows rapidly, tall and straight, and the crown is high, which is the reason why poplar is named "Yang". The pronunciation of "Yang" and "Yang" is the same, "Yang" is "Yang tree", which means a kind of tree with high crown.

Origin of scientific name

The naming of poplar is a very complicated problem, because of the different opinions of scholars, the naming method is confused. Nowadays, some poplar varieties that have been widely cultivated and popularized do not have a correct and unified name. For some poplar varieties cultivated in various regions, it is more confusing.

Sometimes there are only Chinese names or codes, but no Latin names, which often cause undue losses in production. In response to this phenomenon, China has established the China poplar Committee, which is a member of the international poplar Committee. The nomenclature of poplar should be in accordance with the international code for the nomenclature of plants, the international code for the nomenclature of cultivated plants and the international code for the nomenclature of poplar.

Domestic development history

From 1991 to 1995, the Ministry of forestry implemented China's national afforestation project, which was supported by the world bank loan. The project stipulates that 2.77 million mu of high-yield poplar forest will be built within five years, and the afforestation scale is larger than before. China's national afforestation projects emphasize the implementation of intensive management and the promotion of scientific research achievements and technologies. The Ministry of forestry and relevant provinces, cities and counties have set up special agencies to strengthen management. The afforestation quality of this batch of high-yield poplar forests with an area of more than 2 million mu is higher than that of the past due to the adoption of supporting advanced technologies.

From 1996 to 2002, China implemented the "forest resources development and protection project" loaned by the world bank, and built more than 1 million mu poplar fast-growing and high-yield timber forests in Hebei and Liaoning provinces. In this way, only two projects loaned by the world bank in the 1990s created nearly 4 million mu of high-yield poplar forest, which shows that the scale of Poplar Plantation in China is large, and it is very popular with the masses.

China is a country with poor forest resources. Every year, the country imports a large amount of wood to meet the needs of economic construction. The experience at home and abroad has proved that it is an important way to solve the national timber shortage in a short time to vigorously build timber forests and plant fast-growing trees with high-yield cultivation. Planting poplar is good for the country and the people.

Poplar is widely used, not only for wood, but also for processing industry. Poplar has become an important raw material for plywood, fiberboard, paper matches, sanitary chopsticks and packaging industry.

Planting poplar not only has great economic benefits, but also has great ecological and social benefits. Planting poplar in a scientific way can get higher economic income in a short time. The biggest advantage of planting poplar is that it can become timber quickly and the rotation cutting period is short. Generally, it can be harvested and utilized in 5-8 to 12 years. The investment recovery is fast and the income is great. One can plant and harvest mature poplar 4-5 times in one's life. It can be seen that planting poplar is very beneficial.

In 1947, the United Nations Food and Agriculture Organization (FAO) established the international poplar Committee based on tree species. China joined the organization in 1980 and established the China poplar Committee (the only society in China based on tree species).

According to the statistics in 1995, the world's poplar plantation area is 1.4 million hectares, and China's poplar plantation area is about 6 million hectares, accounting for 19% of the total national plantation area, which is four times of the world's poplar plantation area. By 2009, the area of plantation has reached more than 7 million hectares.

In 2015, China's poplar plantation area has exceeded 100 million mu, ranking first in the world. Among them, the Chinese Academy of Forestry Sciences led the breeding of 30 good poplar species, increasing the efficiency by 20%. This achievement recently won the second prize of 2014 National Science and technology progress award.

Up to now, 30 excellent varieties have been widely used in 26 provinces, autonomous regions and cities in China, covering 637200 hectares, covering more than 80% of the main planting area. It is the first country of Poplar Plantation in the world. More than 70% of poplar plantations in the world and China use Populus deltoides, namely Populus euramericana and Populus deltoides.

In the construction of poplar plantation, there are two problems in the East and west of China

First, the problem of poplar in the three North Shelterbelt: the poplar plantation in the three North Shelterbelt is 4 million hectares, and two fifths of the capital and labor are invested in the development of poplar every year, accounting for 27% of the afforestation area in the same period. The serious problems are as follows: 1.4 million hectares of small old trees; serious damage of longicorn beetles and bark beetles; the number of counties affected has increased from 30 to 240, covering an area of about 600000 hectares. The reasons are environmental deterioration, unsuitable land for trees and low level of intensive cultivation.

Second, the productivity of commercial forest in eastern China is low, which accounts for less than 30% of the total area of plantation. The reasons are single variety, aging variety, low productivity and low level of intensive cultivation.

The development strategy of East China plantation base is put forward: large area development along the two banks of East China rivers, namely Songhua River, Nenjiang River, Liaohe River, Haihe River, Yellow River, Huaihai River and Yangtze River.

Based on the financial reports of listed companies, the returns of coal, steel and oil industries are 10%, 12% and 5% respectively, while the rate of return on investment in fast-growing and high-yield forests calculated by the State Forestry Administration is more than 15%, which is far higher than that of other basic industries. In the article "this year's fastest profit growth of wood and paper industry" published in economic reference daily on November 18, 2003, it is pointed out that among the top 10 average profit growth rates of China's top 500 enterprises in 2008, wood processing, paper making and paper products industry ranked first. In addition, it also has the following value-added features:

1. Policy value added: the State encourages and supports forestry, and implements partial or total tax reduction.

2. Land appreciation: the land is limited and non renewable, especially the fast-growing and high-yield forest land is less and less, and the market price has a rising trend year by year.

3. Value added of trees: all trees are alive. As time goes on, they will not depreciate, but also increase their own value. They can also flexibly control the production time according to the market price.

4. Opportunity value added: the forestry system reform is rare in a hundred years, the opportunity is rare, the business opportunity is limited, early investment, early profit.

5. Technology value-added: the growth rate and output of trees can be controlled by using scientific management and advanced technology.

Investment in fast-growing and high-yield forest market mode:

The main investors of fast-growing and high-yield forest are professional poplar planting companies, timber using enterprises and individuals. There are two mature operation modes, one is professional company + forestry base + farmers, the other is wood using enterprise + forestry base. The former model is an organic combination of professional companies who are good at marketing, management and protection units who are skilled in technology and individuals who have capital investment. It can gather the best technology, capital and talents in the society to maximize their benefits. The latter mode is that the wood using enterprises with enough strength can manage the forest land independently or entrust the forest management company to manage it professionally. The purpose of afforestation is to achieve self-sufficiency, and generally do not sell the wood away.

The development direction of these two modes is opposite: the timber production or management enterprises follow the industrial chain of "self production and self consumption", so they will establish their own timber processing plants and other timber plants; in order to control the cost and realize scale production, the timber using enterprises hope to directly participate in or control the source of timber supply, so they will invest a lot of funds in the construction of only woodland It's on. Although the development path of these two models will be in the opposite direction, the result of development is the same goal, that is to build a forestry industry chain integrating production, supply and marketing and a green industry chain combining with the earth's ecology. This is also the future industrial direction and development trend of investors in forest industry.

Species classification

In plants, poplar belongs to Salicaceae. There are three genera in this genus: Populus, Salix and Salix. Populus can be divided into five groups: tacanahaca, Leuce, Aigeiros, turanga and leucoides.

The bark of Populus group is usually gray white and smooth, only the base of old trees is rough. Buds villous or smooth. Leaves tomentose, at least beneath long branches; short branches tomentose or smooth; petioles laterally oblate or subcylindrite. Bracts striped, margin hairy, stigma 2-4-lobed; stamens 5-20, anthers not apiculate. Capsule oblong, usually 2-valved.

The bark of Populus deltoides is flaky and rough. Buds conic, slightly sticky

Chinese PinYin : Yang Shu