Ortiz Escobar M E, Hue N V
Universidade Federal do Ceará, Departamento de Ciências do Solo, Fortaleza-CE 60021-970, Brazil.
Bioresour Technol. 2008 Dec;99(18):8649-54. doi: 10.1016/j.biortech.2008.04.069. Epub 2008 Jun 11.
Soil amendment with organic materials (crop residues animal manure, and green manure) reportedly has positive effects on soil properties, from acidity to plant-nutrient availability. To examine that hypothesis, an incubation study was conducted to assess the changes in some chemical properties of three different tropical soils (Andisol, Ultisol, and Oxisol) amended with chicken manure and green manure (Leucaena leucocephala) at the rate of 10tha(-1). The results showed that organic amendments raised soil pH and EC, regardless of the type of manure used. Manuring lowered the concentrations of Mehlich-3 extractable Ca, P, Mn and Si in all soils and decreased the concentration of Mg in the Ultisol and Oxisol. However, manure amendment led to increases in the concentrations of Mg and K in the Andisol. Organic amendments caused a decrease in KCl extractable Al. Initial soluble C levels were highest in the Oxisol (60micromolg(-1)) and lowest in the Andisol (20micromolg(-1)). The concentration of soluble C decreased exponentially with duration of incubation. Three low molecular weight organic molecules (acetic acid, catechol and oxalic acid) out of the eight tested were found in all manure-amended soils. This study quantified the release of some Al chelating organic acids, the reduction of exchangeable Al, and the changes in major plant-nutrients when organic materials were added to nutrient poor, tropical acid soils.
据报道，用有机物料（作物残茬、动物粪便和绿肥）改良土壤对土壤性质具有积极影响，从酸度到植物养分有效性。为了验证这一假设，进行了一项培养研究，以评估用鸡粪和绿肥（银合欢）以10 t·ha⁻¹的用量改良的三种不同热带土壤（火山灰土、老成土和氧化土）的一些化学性质变化。结果表明，无论使用何种粪肥，有机改良剂均可提高土壤pH值和电导率。施肥降低了所有土壤中Mehlich-3可提取钙、磷、锰和硅的浓度，并降低了老成土和氧化土中镁的浓度。然而，施肥导致火山灰土中镁和钾的浓度增加。有机改良剂使氯化钾可提取铝的含量降低。初始可溶性碳水平在氧化土中最高（60 μmol·g⁻¹），在火山灰土中最低（20 μmol·g⁻¹）。可溶性碳浓度随培养时间呈指数下降。在所有施肥改良的土壤中都发现了所测试的8种低分子量有机分子中的3种（乙酸、儿茶酚和草酸）。本研究对向养分贫瘠的热带酸性土壤添加有机物料时一些铝螯合有机酸的释放、交换性铝的减少以及主要植物养分的变化进行了量化。
