Deciduous broad-leaved forest is the most common forest type in temperate zone. Because of its deciduous leaves in winter and lush in summer, it is also called summer green forest. The climatic characteristics of deciduous broad-leaved forest distribution area are: four distinct seasons throughout the year, hot and rainy in summer and cold in winter. Trees and trees in deciduous broad-leaved forest have broad leaves, usually more or less fluffy and moderate thickness.

Buds have tightly wrapped scales, trunks and branches also have thick bark, which are all structures adapted to the cold environment in winter. There are many types of deciduous broad-leaved forest in China, which can be divided into three types: typical deciduous broad-leaved forest, mountain birch forest and riparian deciduous broad-leaved forest.

China's deciduous broad-leaved forests are mainly distributed in the southeast of Northeast China and North China, including southern Liaoning, southeastern Inner Mongolia, south of Hengshan to Xingxian in Shanxi, south of Loess Plateau in Shandong and Shaanxi, Weihe Plain and northern slope of Qinling, Huixian and Chengxian in Gansu, Funiu Mountain and Huaihe River in Henan, Huaibei Plain in Anhui and Jiangsu, etc.

Why do deciduous broad-leaved forests shed leaves?

Deciduous broad-leaved forest is to reduce transpiration. Broad-leaved trees have large leaves, which are beneficial to transpiration. Autumn is characterized by low temperature, dry climate and little rainfall. Deciduous leaves can reduce transpiration and water loss, which is beneficial to water conservation.

Deciduous broad-leaved forest is widely distributed, which needs 4-6 months of warm growth period with abundant rainfall and 3-4 months of non-cold winter. The average temperature in the hottest month is 13-23℃, the average temperature in Leng Yue is-6℃, and the annual precipitation is 500-1000 mm.