Basic characteristics and causes of vegetation and soil in China
Vegetation in China divides the vegetation in China into 8 regions.
1. Cold temperate deciduous coniferous forest area in northern Daxinganling
Deciduous coniferous forest area in cold temperate zone in northern Daxinganling
The deciduous coniferous forest in the north of Daxing 'anling Mountains in China is a part of the coniferous forest in the north of Eurasia, which belongs to the continuation of the deciduous coniferous forest in the south of East Siberia along the mountain.
Daxinganling is about 600- 1000m above sea level, and some peaks are close to1400 m. The annual average temperature is below-1.2℃-5℃, the July average temperature 16 ~ 20℃, and the annual accumulated temperature (the sum of continuous daily average temperature >: 10℃)100-1700.
The lower part of the mountain is brown forest soil, and the upper part is gray-brown coniferous forest soil, both of which are acidic.
The vegetation here has obvious vertical zoning phenomenon. The valley below 600 meters above sea level is a larch forest containing Mongolian oak. Other tree species include Betula platyphylla, Populus davidiana, Tilia amurensis, Fraxinus mandshurica, Phellodendron amurense and so on. There are Lespedeza bicolor, Corylus heterophylla and Corylus pubescens under the forest.
At an altitude of 600- 1000 meters, it is a rhododendron-Larix gmelinii forest with some Pinus sylvestris forests. There are rhododendrons in the forest-Du Xiang, Vaccinium uliginosum and Vaccinium uliginosum.
At an altitude of1100-1350m, it is a moss-larch forest, containing a few tree species such as spruce and birch. The moss ground cover under the forest is well developed, mainly including Taxodium ascendens, hairpins, tree moss and so on. There is black moss on the trunk, but there are no pine trees.
At an altitude of 1.350 meters, the top is a creeping Chinese pine dwarf forest, as well as white birch and blueberry, all of which have become alpine plants.
Agriculture here is underdeveloped. In the flat valley, there are cool crops harvested once a year, such as potatoes, ganlan and spring barley. Fruit trees include plums, apricots, Vitex negundo and wild fruit-tooth gall.
2. Northeast and North China temperate deciduous broad-leaved forest areas
The territory includes mountainous areas in Northeast China, mountainous areas in North China, hilly areas in Shandong and Liaodong, southeastern Loess Plateau, North China Plain and Guanzhong Plain. Due to the difference of heat conditions between north and south, it can be divided into the following two vegetation zones:
1. temperate coniferous and broad-leaved mixed forest belt:
2. Warm temperate deciduous broad-leaved forest belt:
3. Central and Southwest Evergreen Broad-leaved Forests
Evergreen broad-leaved forest areas in central China and southwest China
This area includes the vast subtropical area between Huaihe River, Qinling Mountain and Nanling Mountain, and the mountainous area on the edge of Qinghai-Tibet Plateau in the west. China's subtropical zone is the only humid subtropical zone with the largest area in the same latitude area of the northern and southern hemispheres in the world, and it is a precious wealth of China.
The climate here is warm and rainy. The frost-free period is 240-300 days, the annual accumulated temperature is 4500-7500℃ at 765,438+065,438+00℃, the annual average temperature is 65,438+04-265,438+0℃, the average temperature in the hottest month is 28-29℃, and the annual precipitation is 65,449. In such a warm and humid climate, the vegetation is dominated by evergreen broad-leaved forest, evergreen coniferous forest and bamboo forest, and the upper part of the mountain and limestone mountain are mixed forests of deciduous broad-leaved and evergreen broad-leaved.
This area is bounded by Songpan, Luding, Shuicheng and Baise, and can be divided into east and west sub-regions.
Eastern subregion
Western subregion
4. South China, Southwest Tropical Rainforest and Monsoon Forest Region
South China, Southwest Tropical Rainforest and Monsoon Forest Region;
This area includes Yunnan, Guangdong, Guangxi and Taiwan Province provinces to the south of the Tropic of Cancer, as well as the mountainous areas and South China Sea islands on the southeast edge of Tibet. It is the region with the most abundant heat in China, with the annual accumulated temperature above 7500-9000℃, the annual average temperature of 2 1-25.5℃, the monthly average temperature of 1 2-20℃ and the annual rainfall of 1200-2200mm. The representative vegetation here is evergreen broad-leaved forest and monsoon forest. Trees have the morphological characteristics of tropical plants such as old stems, roots, air roots and dripping tips, as well as a large number of tropical plants such as vines, nematodes and epiphytes. According to the thermal conditions and vegetation characteristics, this area can be divided into two vegetation zones.
Northern tropical monsoon rain forest belt:
Tropical rain forest and seasonal rain forest belt:
5. Inner Mongolia and Northeast temperate grassland areas
Verb (abbreviation of verb) Inner Mongolia and Northeast temperate grassland areas:
Including the Northeast Plain, Inner Mongolia Plateau and a part of the Loess Plateau. The annual precipitation is 300-500mm, which belongs to temperate semi-humid and semi-arid climate. The vegetation is mainly grass grassland, and drought-tolerant perennial grass is the main vegetation. Plants have obvious xerophytic morphology, such as curly and slender leaves, deep roots and hairy stems and leaves.
This area can be divided into meadow grassland, typical grassland, desertification grassland and forest model.
Meadow grassland belt in northeast China and eastern Inner Mongolia;
Typical grassland belt in central Inner Mongolia;
Desertification grassland in western Inner Mongolia;
Forest and grassland belt in loess plateau;
6. Northwest temperate desert area
Intransitive verb Northwest temperate desert area
Most of the annual precipitation in desert areas in China is below 200mm, and in many places it is less than 100mm, even less than 10mm, which belongs to temperate arid climate and extremely arid climate. Plants here generally have xerophytic characteristics, and their xerophytic forms are: leaf atrophy, leaf degeneration into thorns, leaf complete degeneration, stem and leaf densely villous, or fleshy stems and leaves appear to reduce water evaporation or store water. At the same time, the roots of plants here are particularly developed, some are tens of meters deep, and some are 8- 10 times the weight of aboveground parts, which can absorb water from the depth and breadth of soil layers. This is the result of long-term adaptation and evolution of plants in arid ecological environment. The desert areas in China can be roughly divided into three zones or regions.
Temperate shrub and semi-shrub desert areas:
Semi-shrub and small tree desert belt in temperate zone of northern Xinjiang;
Shrub and semi-shrub desert belt in warm temperate zone of southern Xinjiang;
7. Alpine meadows and grasslands on the Qinghai-Tibet Plateau
Seven. Alpine meadow and grassland in Qinghai-Tibet Plateau;
This area includes most of Qinghai and the southeastern half of Tibet, as well as parts of western Sichuan and northwestern Yunnan. The plateau is more than 4000 meters above sea level, the mountain is more than 5000 meters, and the deep valley on the eastern edge is less than 4000 meters.
The climate here is characterized by changeable and cool weather. The annual average temperature is 1-6℃, the monthly average temperature is -3- 10℃, the July average temperature is 10- 15℃, and the annual precipitation is about 300-500mm. Vegetation is characterized by low grass and narrow leaves to adapt to the cold and windy climate. It can be divided into two vegetation zones.
Alpine meadow belt:
Alpine grassland belt
8. Alpine desert areas
Eight. Alpine desert area
Distributed in the northwest of Tibet, the altitude is above 4500-5000 meters. The annual precipitation is below 100 mm, and in some places it is less than 20 mm. The climate is cold and dry, and the annual average temperature is around℃, but the temperature often rises above 20℃ during the day in summer.
The vegetation is an alpine desert dominated by camel hair, chrysanthemum and Artemisia.