Eurasian grassland is the largest grassland area in the world. It starts from the lower reaches of the Danube in Europe in the west, passes through Romania, Russia, Kazakhstan and Mongolia, and reaches the northeast of China. East-west extension 1 10 longitude. The northern part is the cold temperate coniferous forest belt, and the southern part is the Eurasian desert. About 45-55 degrees north latitude. It extends from east to west to the northeast of China, and turns southwest to the south of Qinghai-Tibet Plateau due to the southeast coast of China. The representative type of Eurasian grassland is the tufted grassland of various needle-built groups. Eurasian grassland is divided into three subregions, namely, Black Sea-Kazakhstan subregion, Central Asia subregion and Qinghai-Tibet Plateau subregion. The Black Sea-Kazakhstan subregion is located in the western half of the Eurasian grassland, and its eastern boundary roughly coincides with that of China, Xinjiang and Kazakhstan. Due to the influence of Mediterranean climate, spring is warm and humid, with two growth peaks in spring and autumn, and short-lived and short-lived plants develop in spring. Central Asia is located in the northeast of Eurasian grassland, mainly including Mongolian Plateau, Songliao Plain and Loess Plateau. Due to the drought in spring, there is only one growth peak in summer all year round, and there is a lack of short-lived and short-lived plants in spring. The Qinghai-Tibet Plateau subregion is the highest grassland area in the world, which belongs to alpine grassland type, and alpine cushion plants often appear in the community. Eurasian grassland is not only the largest and most important grassland on the earth, but also the best preserved grassland at present.