In which areas of China are red soil and yellow soil distributed? What is suitable for growing?

Red soil and yellow soil are two different soils. Red soil, yellow soil and latosol can be collectively referred to as iron-aluminum soil. Next, let's take a look at which areas of red soil and yellow soil are distributed in China and what crops are suitable for planting.

I. the distribution area of red soil and its suitable for planting crops

Red soil is developed under the vegetation of tropical and subtropical rain forest, seasonal rain forest or evergreen broad-leaved forest. Its main feature is the lack of alkali metals and alkaline earth metals and rich in iron and aluminum oxides, showing acidic red. Red soil is the product of the interaction of biological enrichment and desilication iron-rich aluminization weathering process of subtropical organisms under the condition of evergreen broad-leaved forest vegetation in hot and humid climate.

Red soil in China is mainly distributed in the low mountain and hilly areas south of the Yangtze River, including most of Jiangxi and Hunan provinces, southern Yunnan and southeastern Hubei, Guangdong, northern Fujian and some parts of Guizhou, Sichuan, Zhejiang, Anhui and Jiangsu, as well as the south of Xizang. The red soil shows acid-strong acid reaction. Generally speaking, the supply of nitrogen, phosphorus and potassium in hilly red soil is insufficient, the content of available calcium and magnesium is also low, and boron and molybdenum are also very poor. The phenomenon of citrus "mosaic" is often caused by the lack of trace element zinc. Red soil is the northernmost and most widely distributed soil in China, with a total area of 56.9 million hm2, mostly in the vast low mountain and hilly areas of the middle subtropics between 25 °and 31 °N.

The average annual temperature of red soil in China is 1525 ℃, the accumulated temperature of ≧ 10 ℃ is 4500-9500 ℃, the coldest monthly average temperature is 2-15 ℃, the hottest monthly average temperature is 28-38 ℃, the annual rainfall is 1200-2500mm, the winter is warm and dry, the summer is hot and humid, and the dry and wet season is obvious.

From a worldwide point of view, red soil is mainly distributed in Africa, Asia, Oceania and the low latitudes of South and North America, with a limit of 30 °north and south latitude, and is commonly seen in tropical rain forest areas. Soils similar to red soil also exist in Europe, especially on the eastern coast of the Mediterranean and the Balkans. East Asia extends from the Yangtze River in the north to the South China Sea islands and Nanyang Islands in the south, to Taiwan in the east and to the Yunnan-Guizhou Plateau and Hengduan Mountains in the west. The red soil area has heavy rainfall and concentrated rainfall. Sometimes the rainfall can be as high as 200-300 mm at a time. When the ground cover is poor, the rainstorm will cause strong soil erosion.

Red soil is generally suitable for planting rice, tea, silk, sugarcane, mountain is also suitable for planting Chinese fir, paulownia, citrus, bamboo, palm and other economic trees. In addition, red soil is also a good soil for growing oranges.

The acidity of red soil is strong, and the clay weight of red soil is a disadvantageous factor in the utilization of red soil. the fertility of red soil can be improved by applying more organic fertilizer, proper amount of lime and supplementary phosphate fertilizer to prevent red soil erosion. In view of the low content of organic matter in red soil, green manure can be planted to improve the content of organic matter and nitrogen fertility in red soil. There is a general lack of available phosphorus in red soil. Increasing the application of phosphate fertilizer and improving its utilization rate is an important measure to increase agricultural production. The application of lime in red soil can generally achieve good results.

Second, the distribution area of yellow soil and its suitable for planting crops

Yellow soil is developed in subtropical humid mountains or under evergreen broad-leaved forests on the plateau. Its main characteristics are: acidic, the soil layer is often kept moist, because the core soil layer contains a large amount of hydrated iron oxide (goethite) and is yellow, hence the name.

The yellow soil is mainly distributed in the latitude of 23.5 °~ 30 °between north and south. It is distributed in the strips of Central Africa, South America, North America and the southern part of North America, Southeast Asia, South Asia, and the northern part of Australia.

In China, yellow soil is mainly distributed in Sichuan and Guizhou provinces, as well as Yunnan, Fujian, Guangxi, Guangdong, Hunan, Hubei, Zhejiang, Anhui and Taiwan, which is one of the main soil types in mountainous areas of southern China. The law of vertical distribution is obvious. in the vertical zone spectrum of each mountain, the lower part of the yellow soil is generally red soil and the upper part is yellow brown soil. The spectrum of yellow soil zone is closely related to regional water and humidity conditions. Under humid conditions, the vertical zone of yellow soil is wider, some can be as wide as 1000 meters, and there are many types, and there are often more than two yellow soil subtypes. The lower limit of vertical distribution varies greatly, the lower limit is about 500m, and the higher one can be moved to 1800 m. With the difference of the lower limit, the upper limit of the vertical distribution of yellow soil varies, generally between 800m and 1600m, and above 2200m and 2600m in the mountains of Yunnan plateau.

Yellow soil is an important soil resource in Chongqing, its area is 2371750.39hm2, accounting for 28.78% of the total land area. Mainly distributed at altitude