④ North China deciduous broad-leaved forest, Pinus tabulaeformis and Platycladus orientalis. The range of this forest area is roughly from southern Liaoning in the north to the north of Huaihe River in the south, including the vast mountainous areas in North China. In 20 14, there were only scattered deciduous broad-leaved forests dominated by oak, birch and Populus davidiana, and small coniferous forests such as Platycladus orientalis and Pinus tabulaeformis. A few Fraxinus mandshurica, maple, linden and poplar grow in parts of the valley with good water conditions. There are also small pieces of Larix principis-rupprechtii, spruce (with green stems and white stems) and a few firs in higher mountainous areas. This area needs to vigorously protect and cultivate forests, produce wood and fuelwood, conserve water and maintain soil.
⑤ South China tropical monsoon forest. Distributed in the south of the Tropic of Cancer. The main forest areas are Hainan Island and South China Sea Islands, southern Taiwan Province Province, Honghe Hani and Yi Autonomous Prefecture and Xishuangbanna. The forest basically belongs to tropical monsoon forest, and the root phenomenon is obvious in the wet valley. There are tall tree ferns and palm plants under the forest, and orchids, ferns and Araceae plants are attached to the trunk, showing the landscape of tropical rain forest. The forest area is rich in forest plants, including Dipterocarpaceae trees, such as plum blossom, bole, Dipterocarpaceae and ginkgo biloba, and tropical trees, such as butterfly tree, Face, longan, Azadirachta indica, Azadirachta indica and Adiantum ovatum. There are also wild flowers in Xishuangbanna and the southernmost part of Guangxi. In addition, Lu Junsong and Pinus yunnanensis are also distributed in Hainan Island and southern Yunnan. In the mountainous areas with higher altitude, there are evergreen broad-leaved forests dominated by evergreen FAGACEAE trees. The valley area is low in altitude, with little rainfall, and the drought phenomenon is obvious, such as the dry tropical forest with thick bark and closed flowers and trees, Albizia Albizia (Haig, white dove) and Dendrocalamus spinulosus, similar to the savanna in the south of Hainan Island.
The tropical forest region of South China is the region with the most abundant heat in China, but in the long dry season, the low temperature of 10℃ or below occasionally occurs. Therefore, measures should be taken to prevent dry wind and low temperature. Before planting rubber in Hainan Island, planting windbreaks received good benefits.
⑥ China's forests are not only distributed in the above-mentioned forest areas, but also in the vast arid and semi-arid areas, oases, river banks and mountainous areas with a certain height in northwest China, such as Populus euphratica forests in Tarim River Basin, Tianshan Mountain and Qilian Mountain. In addition, there are plains, basins and deltas in the east of China, and the original natural forests have been destroyed for a long time, with only sporadic tree species and small jungles. Since 1950s, farmland shelterbelts, agroforestry and afforestation have been established one after another. The forest coverage rate in many counties has reached 10 ~ 15%. Farmland shelterbelts in these areas have played a great role in protecting farmland, planting trees around them has improved and beautified the environment, and provided wood, fuelwood and various forest products needed locally. By 1989, the planted area in China reached 38.3 million hectares, accounting for 1/3 of the total planted area in the world.