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註釋Materials for soil development; Processes of soil development; Physical properties of soils; Soil moisture; Origin and classification of soils; Chemical properties of soils; Soil reaction; Lime and its use; Soil organisms - kinds, numbers, activities, and relation to soil productivity; Soil organic matter; Cover and green-manure crops; Farm manures; Nutrient requirement of plants; Fertilizers and fertilizer materials; Fertilizer practices; Conserving soil; Soil fertility maintenance and productivity rating of soil; Soils and agriculture of arid regions; Irrigation; Soil resources.