尿素的化学性质及在土壤中的转化
氮肥应用资料
氮肥（华盛顿州立大学资料）
Effects of urea fertigation of apple trees on soil pH, exchangeable cations and extractable manganese in a sandy loam soil in New Zealand
the biology of soil compaction
Soil Nitrogen and Sulfur
Soil Nitrogen and Sulfur
Contribution of Bacteria to Initial Input and Cycling of Nitrogen in Soils
土壤养分等级分级标准
全国第二次土壤普查养分分级标准
