Cover crop effects on soybean residue decomposition and P release in no-tillage systems of Argentina

Cover crops (CC) provide many benefits to soils but their effect on decomposition of previous crop residues and release of nutrients in continuous no-tillage soybean [Glycine max (L.) Merr.] production are little known. Our objective was to quantify CC effects on decomposition and phosphorus (P) rel...

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Detalles Bibliográficos
Autores: Varela, María Florencia, Scianca, Carlos María, Taboada, Miguel Angel, Rubio, Gerardo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2014
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/31746
Acceso en línea:http://hdl.handle.net/11336/31746
Access Level:acceso abierto
Palabra clave:Soybean Residues
Phosphorus
Nutrient Cycling
Soil Organic Carbon
https://purl.org/becyt/ford/4.1
https://purl.org/becyt/ford/4
Descripción
Sumario:Cover crops (CC) provide many benefits to soils but their effect on decomposition of previous crop residues and release of nutrients in continuous no-tillage soybean [Glycine max (L.) Merr.] production are little known. Our objective was to quantify CC effects on decomposition and phosphorus (P) release from soybean residue using litterbags. Three CC species (oat, Avena sativa L.; rye, Secale cereal L.; and rye grass, Lolium multiflorum L.) and a no CC control were evaluated. Temperature, moisture content, microbial biomass and microbial activity were measured in the surface 2 cm of soil and residues. Cover crops increased soybean residue decomposition slightly both years (8.2 and 6.4%). Phosphorus release from soybean residue did not show any significant differences. Cover crops increased microbial biomass quantity and activity in both soil and residue samples (p < 0.001, p = 0.049 for soil and residue microbial biomass; p = 0.060, p = 0.003 for soil and residue microbial activity, respectively). Increased residue decomposition with CC was associated with higher soil and residue microbial biomass and activity, higher near-surface (0–2 cm) moisture content (due to shading) and soil organic carbon enrichment by CC. Even though CC increased soybean residue decomposition (233 kg ha−1), this effect was compensated for by the annual addition of approximately 6500 kg ha−1 of CC biomass. This study demonstrated another role for CC when calibrating models that simulate the decomposition of residues in no-tillage systems.