土壤是农业的基础。不断改善土壤条件是确保农业高产稳产的必要前提。土壤具有一系列不同于其他农业资源的特殊属性:(1)资源数量的有限性。可利用的土壤不能无限增加。(2)成土母质的非再生性。一般岩石从开始风化,到形成一厘米厚的土壤,约需一万三千年到二万二千年。土壤流失之后,在可预见期间无法复原。(3)使 Soil is the foundation of agriculture. Continuous improvement of soil conditions is a necessary prerequisite for ensuring a high and stable agricultural production. Soil has a series of special attributes that are different from other agricultural resources: (1) The limited amount of resources. The available soil can not be increased indefinitely. (2) Soil non-renewable nature of the parent material. General rock from the beginning of weathering, to the formation of a centimeter thick soil, about 13,000 to 22,000 years. After soil loss, it can not be recovered in the foreseeable future. (3) make