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白土是太湖流域的主要低产土壤之一,过去水稻的产量仅三四百斤,約比一般土壤的产量低三分之一。1958年土壤研究所根据江苏省的要求,在太湖地区进行了低产白土的調查研究。白土又叫白土头或淀煞白土,在太湖北部和西部的几个县中,約佔耕地面积的十分之一。这种土壤具有一些共同的剖面特征。表土的顏色较淺,有机質和含氮量也较少,表土下有一个紧密的犂底层,在犂底层下有一个白土层。这个白土层一般出現于20厘米左右,本身的厚度約为20厘米,顏色为白灰或灰白色,这就是白土这个名称的由来。在白土层下,是比较粘重的黄泥。根据土壤的机械分析結果来判断,黄
Clay is one of the major low-yielding soils in the Taihu Lake basin. In the past, the yield of paddy rice was only 300kg, about one-third less than that of ordinary soils. According to the request of Jiangsu Province, the Institute of Soil Science in 1958 conducted a survey on low-yield white clay in the Taihu Lake region. Clay is also called white clay or clay white clay, in the northern and western Taihu several counties, accounting for about one-tenth of the area of arable land. This soil has some common profile features. Topsoil lighter color, organic matter and nitrogen content is also less, there is a close bottom plow under the soil, there is a white soil layer under the plow. This white soil usually appears in about 20 cm, its thickness is about 20 cm, the color is white or gray, and this is the origin of the name white clay. Under the clay layer, is more sticky yellow mud. According to the mechanical analysis of soil to determine the results, yellow