在我国由南向北土壤的颜色是不一样的。南方多为砖红色的土壤,中部多为浅褐色的土壤,到东北大平原就变成了肥沃的黑色土壤。这些不同颜色的土壤是在不同的自然条件下形成的。长江以南地区,在高温多雨的气候条件下,风化作用强烈,风化壳中的钾、钠、钙、镁等活泼元素被雨水淋溶带走,而铁、铝等不活泼元素随水流的渗透,沉淀在土壤中。 The color of soil from south to north in our country is not the same. Most of the southern red brick soil, the central mostly light brown soil, to the northeast Great Plains has become a fertile black soil. These different colored soils are formed under different natural conditions. In the south of the Yangtze River, under the high temperature and the rainy weather, the weathering effect is strong. The active elements such as potassium, sodium, calcium and magnesium in weathering crust are leached by rainwater. However, the infiltration of inert elements such as iron and aluminum with water flow , Precipitation in the soil.