| [Visitor (116.162.*.*)]answers [Chinese ] | Time :2025-09-02 |  Lime soil: a soil with strong acidity and iron-aluminum deposits under the low temperature and humid climate and coniferous vegetation in cold temperate zones. China is also known as gray soil. It is distributed in a continuous belt in northern Eurasia and Canada, and is distributed in the vertical zone of high mountains and subalpine in the central and northern parts of the Great Xing'an Mountains and the southeastern edge of the Qinghai-Tibet Plateau in China. Under cold and wet coniferous forests, the upper layer of the soil has a deep litter layer (01) and a semi-decomposed litter layer (02). The strong acidic organic acids formed by the decomposition of litter destroy the silicates and cause them to leach and accumulate downward in the states of humus and iron and aluminum oxides, forming a grayish-white and relatively enriched ash layer of silicon oxide (A8sub＞2.There is often stagnant water on the surface, and when the soil is in a moist state, it is accompanied by anaerobic reduction, ferrous leaching, iron removal phenomenon, and rusty markings in the gray-white soil layer. Underneath it are dark humus sedimentary layers (Bh) and iron-aluminum oxide sedimentary layers (Bir). The gray soil has the characteristics of coarse and cohesive texture, strong acidic reaction (pH 4.0~5.5), low base saturation and obvious profile differentiation. If the A2 layer is more gray, the bottom layer (B layer) iron, aluminum and humus combine into a disk, which is called gray soil. In the United States, it is called gray soil in the classification of soil systems. The lime soil distribution area is an important forest production base in China, where the climate is cold and humid, the soil layer is shallow, and the fertility is low, so it is not suitable for large-scale agricultural use.Aergized soil is also a subclass name under the general category of lime soil. Gray soil can be divided into three subcategories: gray soil, brown gray soil and latent gray soil (according to the classification method delineated by Chinese scientists). Among them, the gray soil subclass has a strong degree of ashing, the profile configuration is 0-AH-E-Bsh-C, there is an obvious and continuous grayish-white gray layer in the profile, and there is obvious iron and aluminum precipitation layer, and there is also a certain amount of humus... |
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