Where is the dark brown soil distributed in China? What is suitable for growing?

Dark brown soil is a zonal soil developed under temperate humid monsoon climate and coniferous and broad-leaved mixed forest. it is an independent soil classified by brown forest soil after the founding of the people's Republic of China. The total K content is 15.7-19.3, the profile configuration is O-AB-Bt-C, the surface humus accumulates, the whole profile shows moderate to slightly acidic reaction, the base saturation is 60-80%, and the contents of clay and iron and manganese in the middle of the section are higher than those of the upper and lower layers of the leached soil. Dark brown soil, also known as dark brown forest soil, used to be called brown podzolic soil and gray brown soil. It was not until 1960 that it was formally established as dark brown forest soil, that is, dark brown soil, after the first national soil survey.

So, which areas of dark brown soil are mainly distributed in China? What kind of crops are suitable for growing?

Distribution area of dark brown soil in China

Dark brown soil is widely distributed, with a total area of 40.19 million hm ², is the largest kind of forest soil in the northeast, mainly distributed in Xiaoxinganling, Changbai Mountain, Wanda Mountain and the eastern slope of Daxing'an Mountains, extending to Heilongjiang in the north, central Daxinganling in the west, Wusuli River on the border in the east, Tieling and Qingyuan area and Siping and Tonghua in Liaoning Province in the south.

Dark brown soil changes from brown coniferous forest soil to north (upward) and brown soil to south (downward). The specific distribution is below 800m on the east slope of Daxing'an Mountains, 900m above sea level in Xiaoxing'an Mountains, and 1100m above sea level in Wanda Mountain and Changbai Mountain. it is one of the largest forest soils in Northeast China. Dark brown soil is also widely distributed over brown soil in the vertical zone spectrum of other mountainous areas in China.

Due to the specific regional distribution, dark brown soil is often accompanied by special composition conditions. The annual average temperature is between-1-5 ℃, the annual ≥ 10 ℃ accumulated temperature is 2000-3 000 ℃, the soil freezing depth is 1-2, the maximum depth is 3 m, and the freezing time is 120-200 days. Even in some areas, the seasonal permafrost is particularly obvious. Annual rainfall 600~1100mm, frost-free period 115,135days, belongs to temperate humid climate zone.

The natural vegetation in dark brown soil is mainly coniferous and broad-leaved mixed forest dominated by Pinus koraiensis. Due to the humid climate, there are many kinds of plants, a total of more than 2000 species. Coniferous species are mainly negative and semi-negative species such as Korean pine, sand pine, fish-scale spruce and red-bark fir. There are many deciduous broad-leaved tree species, including white birch, black birch, maple birch, Mongolian tussah, spring elm, Juglans mandshurica, yellow pineapple and Fraxinus mandshurica. Under the forest shrubs and herbs are luxuriant, common shrubs are hairy hazelnut, mountain plum blossom, Acanthopanax senticosus, health grass and cloves and other plants. Common herbs are Equisetum, Lilium verticillata, Eucalyptus, tundra and so on. Now, although the proportion of secondary forest is gradually increasing, it is still the main forest area in Northeast China. The topography of the area is mainly mountainous.

Crops suitable for growing in dark brown soil

As a forestry base, dark brown soil should be used mainly for the development of forestry. Larch, Pinus koraiensis, Fraxinus mandshurica and Juglans mandshurica like fertilizer and humidity, so they should be planted on typical dark brown soil or meadow dark brown soil in the middle and lower part of the hillside, especially Pinus koraiensis, which is a tree species with good quality and requires high soil conditions. it is most suitable to be planted on meadow dark brown soil and typical dark brown soil. Spruce and birch have strong adaptability and can tolerate barren, so they can be planted in white serous dark brown soil and ash dark brown soil with poor soil conditions.

In order to solve the supply of some grain and vegetables in the forest area, we can consider reclaiming a certain area and planting crops and vegetables on the meadow dark brown soil, the gully dark brown soil and the typical dark brown soil with thick humus layer.

To grow crops, you can choose cold-tolerant and early-maturing crop varieties, such as wheat and potatoes, cabbage, radish and cabbage. According to the characteristics and advantages of the mountain area, we can also develop diversified economy, sericulture, beekeeping and planting fruit trees, so as to comprehensively utilize and develop mountain resources.

In addition, it is more suitable to develop ginseng in dark brown soil. Actively developing the production of edible fungi, such as artificial culture of noble edible fungi such as Ganoderma lucidum and valuable medicinal materials, is also an effective way for comprehensive development and rational utilization in dark brown soil areas.