The black soil in the Northeast Plain is very fertile. What is the reason for the formation of black soil?

Northeast China has a high latitude and belongs to temperate monsoon climate, with cold and humid climate, thick soil and seasonal frozen soil. It is rainy in summer and autumn, the soil often forms stagnant water in the upper layer, meadow herbs flourish, and a large number of organic residues enter the ground and underground of the soil. In the long winter, microbial activities are inhibited, and organic matter is slowly decomposed, which is transformed into a large amount of humus accumulated in the upper part of the soil, forming a dark black humus layer. The salt base in the soil is leached, carbonate is also removed from the soil, and the soil is neutral to slightly acidic. The seasonal stagnant water in the upper layer causes the decrease of iron and manganese in the soil, which is oxidized to form iron and manganese nodules in the dry season, especially in the subsurface layer.

Therefore, the black soil in Northeast China is a special meadow process, which evolved after the surface vegetation died and formed humus for a long time.

Second, where does the black land in Northeast China refer to?

The total area of black soil area in Northeast China is about 6.5438+0.03 million square kilometers, of which the typical black soil area is about 6.5438+0.7 million square kilometers. This is the main commodity grain base in China, producing about 22.5-25 billion kilograms of commodity grain every year. The crescent-shaped black land distributed in Heilongjiang and Jilin provinces is the most fertile land in China. With a total area of10 million hectares, more than 7 million hectares of cultivated land have been cultivated, and its grain output has accounted for more than 60% of the two provinces.

3. What are the advantages of black land in Northeast China?

In the natural state, the humus layer of black soil can be as thick as 1 m, with rich nutrient content and high fertility level. After the reclamation of black soil, the content of humus decreased, and the soil erosion was obvious because of the heavy parent material, which should be paid attention to in the utilization of black soil. Black soil in Northeast China is one of the most fertile soils in China, and its distribution area is an important grain base. Wide adaptability, especially suitable for the growth of soybean, corn, millet and wheat.

Therefore, black soil is a very precious land resource, which can be said to be "the giant panda in cultivated land". However, in recent years, due to the restriction of natural factors and the destruction of human activities, soil erosion in the black soil area of Northeast China has become increasingly serious and the ecological environment has deteriorated. So, let's participate in the action to protect the black land and win the "tough battle" of the black land!