1. In the smoke scene south of Shenzui, I looked at the vast grassland in Saibei and admired the son of the Five Tombs.
2. The spring breeze takes Qingyang Road, and the sunset takes Yingqiu Grassland.
3. The grass is green and willow is thick, and the jade pot is full of wine.
4. The white grass smells the sound of wild geese, and the horseshoe sound in the yellow sand dunes is light.
5. Outside of Manoda, I am fascinated by Bi Grassland.
Grassland:
Grassland is a kind of earth ecosystem, which is divided into tropical grassland and temperate grassland, and it is the most widely distributed vegetation type on the earth. The reason for the formation of grassland is that when the soil layer is thin or there is little precipitation, herbaceous plants are less affected, while woody plants cannot grow widely.
China is one of the countries with the richest grassland resources in the world, with a total grassland area of nearly 400 million hectares, accounting for 40% of the total land area, which is three times of the existing cultivated land area.
Temperate grassland:
Zonal vegetation types composed of perennial herbs in temperate semi-arid to semi-humid environment.
Leng Xia is warm in winter in grassland area, with less precipitation and strong evaporation. The weak leaching of soil and the developed calcification process limit the growth of tall trees. The community structure of grassland plants is simple and seasonal. There are mainly xerophytic grasses with narrow leaves, such as cryptospermum, Stipa, Pinctada and other genera, as well as compositae, Leguminosae, Cyperaceae and some rhizome grasses.
According to different hydrothermal conditions, grasslands can be divided into typical grasslands, desertified grasslands and meadow grasslands. Typical grassland is the most widely distributed type in grassland, which consists of typical xerophytes, mainly tufted grasses, accompanied by a small number of xerophytes and moderately xerophytes, small shrubs and shrubs.
The causes of grassland formation:
Mainly because of the thin soil layer or less precipitation, herbaceous plants are less affected, while woody plants cannot grow widely. Grassland originated in the dry and cold period of global climate (appearing in Cenozoic), similar to the wilderness, desert and shrub land where they often blend. In fact, Gramineae itself (Gramineae and Gramineae) only evolved in the early Cenozoic. The earliest date of grassland appearance varies from place to place.
In many areas, a series of vegetation types can be found in Cenozoic fossils, when the climate changed gradually. For example, in the past 50 million years, the tropical rain forest in central Australia has been replaced by wilderness, grassland and finally desert. In some places, the expansion of grassland to modern scale only appeared in the extremely dry and cold period 2 million years ago, which was called the "ice age" in the northern temperate zone.