What is "high loess slope"?

"Loess Plateau", also called "Loess Plateau", not only belongs to one province, but spans several provinces. It mainly includes: Shanxi Province, Northern Shaanxi Province, Gansu Province (except Longnan City, Pingliang City, Ningxian County and Zhengning County of Qingyang City), Qinghai Province, Ningxia Hui Autonomous Region and Henan Province.

geographical position

The Loess Plateau of the Yellow River Basin starts from Wushaoling in the west, reaches Taihang Mountain in the east, Qinling Mountain in the south and Inner Mongolia Plateau in the north (roughly bounded by the Great Wall), involving 46 places (leagues, prefectures and cities) and 282 counties (flags, cities and districts) in 7 provinces (regions) of Qinghai, Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi and Henan. The total area of the region is 635,000 square kilometers; Among them, the soil erosion area is 454,000 square kilometers (water erosion area is 33.7 square kilometers, wind erosion area is 1 17000 square kilometers), and the annual sediment input of the Yellow River is 654.38+0.6 billion tons, which is the most serious soil erosion area in China and even the world, and the most fragile ecological environment.

physioclimate

The Loess Plateau belongs to a (warm) temperate (continental) monsoon climate, which is cold, dry and windy in winter and spring due to the influence of polar dry and cold air masses. In summer and autumn, it is affected by the western Pacific subtropical high and the Indian Ocean low, with high temperature and rainy weather. The average annual rainfall is 466mm, and the general trend is decreasing from the southeast to the northwest, with 600-700 mm in the southeast, 300-400 mm in the middle and/or 0/00-200 mm in the northwest. Taking the annual rainfall lines of 200 mm and 400 mm as the boundary, it is arid in the northwest, semi-arid in the middle and semi-humid in the southeast. There are many geological disasters in the Loess Plateau of northern Shaanxi, with thick and loose soil layers and changeable weather in summer. Rainstorms are prone to disasters such as mudslides and flash floods.