Populus euphratica

Populus euphratica

Populus euphratica is a kind of plant belonging to Angiospermae, dicotyledona, pentadactyla, Salicaceae and Populus. It is a deciduous medium-sized natural tree with a diameter of 1.5 meters. Its wood is fine and soft, and its leaves are broad and fragrant. It is one of the rare tree species in nature, which is resistant to drought and waterlogging.

The age of Populus euphratica can reach 200 years, the trunk is straight, 10-15 meters high, and it is sparse shrub like. The leaves are peculiar, because they grow in the extremely arid desert area. In order to adapt to the arid environment, the leaves growing on the tender branches of young trees are as narrow as willows, while the leaves on the old branches of big trees are as round as poplar.

morphological character

Populus euphratica can sprout seedlings from the roots, can endure the arid environment in the desert, and has strong tolerance to saline alkali. The bark is grayish brown, the lower part is striped; the sprouts are fine, round, smooth or slightly villous. Buds elliptic, smooth, brown, ca. 7 mm long. The leaves on the long branches, seedlings and saplings are linear lanceolate or narrow lanceolate, with whole or irregular sparse wavy tooth margin; the branchlets of adult trees are muddy yellow, with short villi or glabrous, rich in salt, and salty when biting. the leaf shape is varied, oval, oval lanceolate, triangular, ovoid or kidney shaped, 25 cm in length and 3 cm in width, with 2-4 pairs of coarse teeth at the apex, wedge-shaped, broadly wedge-shaped, round or truncate at the base, with 2 glandular dots and the same color on both sides; the petiole is sparse subcordate or broadly wedge-shaped; the petiole is 1-3 cm long, smooth, slightly flat, about the same length as the leaf blade, and the petiole of sprouting branch is very short, only 1 cm long, with short villi or hairs Smooth. There are many gaps on the edge of the leaves, which are a bit like maple leaves. The leaves are leathery and hairy on the branches, and even the young leaves are like willow leaves, so as to reduce the evaporation of water. Therefore, it is also known as "variable leaf Poplar" and "variable leaf Poplar". dioecious, rhombic inflorescence; bracts rhombic, upper often serrate, caducous; stamens 15-25, anthers purplish red, disk membranous, margin irregularly dentate; bracts slightly rhombic, about 3 mm long, upper part sparsely dentate; female inflorescence 2.5 cm long, fruiting 9 cm long, inflorescence axis short villous or glabrous, Ovary pedunculate, stigma broad, purplish red, long ovate, pubescent or glabrous, ovary stalk about as long as ovary, stigma 3,2-lobed, bright red or yellowish green. Capsule long ovoid, 10-12 mm long, 2-3-valved, glabrous. The flowering period is may, and the fruiting period is July to August.

Distinguishing features

The back of the leaves is blue-green, the long branches and sprouting branches and leaves are entire, and the upper part of the short branches and leaves is serrated; the disk is membranous.

Distribution range

Populus euphratica is produced in western Inner Mongolia, Xinjiang, Gansu and Qinghai. Foreign distribution in Mongolia, Russia (part of Central Asia and the Caucasus), Egypt, Syria, India, Iran, Afghanistan, Pakistan and other places.

Growth habit

Populus euphratica is a tree species in arid continental climate. It is light loving, heat resistant, atmospheric drought resistant, saline alkali resistant and windy sand resistant. It can not grow well in hot and humid climate and heavy soil. Populus euphratica requires sandy soil, where desert rivers flow, Populus euphratica will follow. And the desert river changes quite frequently, so Populus euphratica leaves traces of stopping everywhere in the desert. Populus euphratica depends on the protection of its root system. If the groundwater level is not less than 4 meters, Populus euphratica can live at ease. When the groundwater level falls to 6-9 meters, Populus euphratica will be depressed. If the groundwater level goes down, Populus euphratica will die. Populus euphratica is a typical mesophytic to mesophytic plant in the desert area of Asia and Africa, which adapts to the extreme arid continental climate for a long time. It likes light, soil moisture, atmospheric drought, high temperature and cold. It is suitable for the warm temperate desert climate with the accumulated temperature above 10 ℃ between 2000 ~ 4500 ℃ and the warm temperate desert climate with the accumulated temperature above 4000 ℃ Fine sand along the river bank and flood plain grows best on sandy soil. It can endure the attack of extreme maximum temperature 45 ℃ and extreme minimum temperature - 40 ℃. Populus euphratica has strong salt tolerance. When the total salt content of soil is less than 1%, it grows well; when the total salt content is 2-3%, its growth is inhibited; when the total salt content is more than 3%, it dies in pieces. Populus euphratica has strong adaptability to large range of temperature changes. It grows mainly by diving or river flooding water, so it has roots extending near the shallow water layer, strong root pressure and leaves containing sodium bicarbonate, so it can resist drought and salt. Populus euphratica is the only tree species living in the desert. It has witnessed the process of desertification in the arid area of Northwest China from beginning to end. Although it has retreated to the desert riparian zone, it is still the soul of life in the desert known as "the sea of death". In the desert, as long as you see rows of fresh or dry Populus euphratica, you can judge that there was water flowing there. Because of this, some people call Populus euphratica an "irresponsible mother". It leaves its descendants everywhere, regardless of their lives. In fact, this is a kind of helpless restriction on the environment.

Main value

ecological value

Populus euphratica is a special precious forest resource in desert area. It is resistant to cold, drought, salt, wind and sand, and has strong vitality. Populus euphratica forest is a unique and precious forest resource in desert area. Its primary function is to prevent wind and fix sand, create suitable oasis climate and form fertile soil. For thousands of years, Populus euphratica has resolutely guarded the border desert and watched the wind and sand. Populus euphratica is also known as the "Guardian God of the desert". Populus euphratica plays an important role in stabilizing the ecological balance of desert river zone, preventing wind and fixing sand, regulating oasis climate and forming fertile forest soil. It is a natural barrier for the development of agriculture and animal husbandry in desert areas. Populus euphratica is an ancient tree species, which has important scientific value for the study of climate change, river changes, flora evolution and ancient economic and cultural development in the desert area of Asia and Africa. Populus euphratica forest can improve desert ecology. In Xinjiang, Inner Mongolia and western Gansu, a considerable part is occupied by Gobi and desert, which is dry and rainless, especially in Tarim Basin in southern Xinjiang. Populus euphratica is mainly distributed around the Taklimakan Desert, like a green Great Wall, which tightly locks in the expansion of mobile sand dunes. the agricultural areas of Xinjiang are mainly distributed in the oases of the northern and southern Xinjiang basin, surrounded by desert and Gobi, and under the threat of drought and sandstorm. The areas of Inner Mongolia and western Gansu are also in similar natural environment. Under such harsh natural conditions, the Populus euphratica forests distributed on both banks of rivers and flood eroded land in these areas cannot be ignored. As a result of the existence of these Populus euphratica forests, the severe drought climate was eased. In the middle of Tarim River in southern Xinjiang, the natural Populus euphratica forests distributed on both sides of the upper reaches and in the vast areas of the lower reaches constitute a natural forest belt with a length of hundreds of kilometers. This natural forest belt has played a positive role in preventing wind and fixing sand, regulating climate, effectively preventing and slowing down the northward movement of Taklimakan Desert in the south, ensuring oasis agricultural production and stable life of residents, etc. as a large number of Populus euphratica forests grow on both sides of the river, it protects the river bank, reduces soil erosion and loss, and stabilizes the river bed. The shading and covering of Populus euphratica forest, on the one hand, enhanced the biological drainage of soil, on the other hand, relatively slowed down the direct evaporation of upper soil moisture, inhibited the process of soil salinization, thus played a role in improving the soil to a certain extent. As a desert forest, Populus euphratica plays an important role in the vast desert of Northwest China, which is difficult to evaluate with general figures.

The role of Medicine

Resin: clearing away heat and toxin, making acid and relieving pain. For sore throat, toothache, lymph node tuberculosis, stomach, duodenal ulcer, stomachache, excessive gastric acid; external treatment of otitis media, hemorrhoids. root: insect repellent. inflorescence: hemostasis. External hemostasis. usage and dosage: jatroponin (resin. Crude): 2 ~ 3 yuan, decocted in water; suitable for external use. Root: 3-5 yuan, fried in water.

economic value

Populus euphratica has ornamental and horticultural uses, evergreen, beautiful tree shape, is an excellent street tree, garden tree species. Wood is used for building, bridge, farm tools, furniture, etc. The length of wood fiber is 0.5-2.2 mm, with an average length of 1.14 mm. It is also a good raw material for papermaking. It is an excellent tree species for greening the arid and saline areas in Northwest China. The whole body of Populus euphratica is a treasure: its wood is hard, water-resistant and anti-corrosion, and it has been immortal for thousands of years. It is the first-class building and furniture material. The building materials of Populus euphratica in Loulan, Niya and other desert cities are still well preserved. The leaves are rich in protein and salt, which is a good feed for livestock to overwinter. The Populus euphratica has long fiber, which is a good raw material for papermaking, and the dead branches are a good fuel. Populus euphratica forests and twigs are important forages in desert areas; although wood is not ideal, it is still an important timber in the wood deficient desert; leaves and flowers can be used as medicine, so Populus euphratica is a treasure tree in the desert. Populus euphratica and Populus deltoides have strong anti-corrosion ability, especially after soaking in water. In saline alkali area, Populus euphratica wood is used as the basic material of bridge and culvert, which is durable. However, under the condition of impermanence of humidity and dryness, the anti-corrosion ability decreased significantly, and it would all decay in less than 2 years. In the Tarim River Basin of Southern Xinjiang, the local people often use the dry wood of Populus euphratica to chisel the canoe, which is called "kapen" in Uighur, and has become an important tool for fishing and crossing the river. The fiber quality of Populus euphratica wood is better than other poplars, and it can be used as raw material for papermaking industry. According to Yang Tingfu of Xinjiang Bayi Agricultural College, the average length of Populus euphratica wood fiber is 1135.83 μ m, the absolute maximum length is 2204.52 μ m, the average amplitude of wood fiber is 23.17 μ m, and the ratio of length to amplitude is 68.97. Populus euphratica and other species

Chinese PinYin : Hu Yang