Nutrient recycling and physical indicators of an alley cropping system in a sandy loam soil in the pre-Amazon region of Brazil

• Published in: Nutrient cycling in agroecosystems 2010-03, Vol.86 (2), p.189-198
• Main Authors: das Chagas Ferreira Aguiar, Alana, Bicudo, Silvio José, Costa Sobrinho, João Reis Salgado, Martins, Alba Leonor Silva, Coelho, Kátia Pereira, de Moura, Emanoel Gomes
• Format: Article
• Language: English
• Subjects: Acacia; Aeration; Agricultural management; Agriculture; Alley cropping; Biomedical and Life Sciences; Bulk density; Cereal crops; Corn; Crop production; Crop residues; Cropping systems; Farming systems; Indicators; Legumes; Leucaena; Life Sciences; Loam; Loam soils; Nutrients; Organic chemistry; Original Article; Phosphorus; Pigeonpeas; Porosity; Productivity; Sandy loam; Sandy soils; Soil aeration; Soil analysis; Soil fertility; Soil improvement; Soil management; Soil porosity; Soil quality; Streets; Sustainability management; Tillage; Tropical environments
• ISSN: 1385-1314; 1573-0867
• DOI: 10.1007/s10705-009-9283-6

The sustainable management of soils has proved a key challenge for the smallholder agriculture in southeastern Amazonia, Brazil. We assessed the capacity of an alley cropping system to sustain corn productivity. The experiment included six treatments: Clitoria + Pigeon Pea; Leucaena + Pigeon Pea; Acacia + Pigeon Pea; Clitoria + Leucaena; Leucaena + Acacia and Control treatment (no legumes). We determined chemical and physical indicators of soil quality. Leucaena had the highest macronutrient concentrations (40.17 g N kg −1 ), except for P. All legumes had high Ca (13.82–17.84 g kg −1 ) and very low P (0.51–2.83 g kg −1 ) and Mg (1.73–2.92 g kg −1 ) concentrations. Acacia had the lowest N, P, K and Mg concentrations. Pre-planting soil analysis indicated that soil quality indicators were below the critical levels needed for a productive agricultural system, especially for phosphorus, sum of bases and base saturation. Physical indicators of quality, such as bulk density (1.40–1.30 Mg m −3 ), total porosity (0.46–0.50 m m −3 ) and soil aeration capacity (0.10–0.17 m m −3 ), were substantially improved as a result of the surface application of residues. There was a cumulative effect of residue application on corn crop productivity. Because of its capacity to recycle nutrients and improve soil quality over the period of 3 years, alley cropping in association with no-tillage, can be an efficient strategy for maintaining productivity in the low-fertility soils of the humid tropics.