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Individual study: Long-term effects of conservation tillage on organic fractions in two soils in southwest of Spain

Published source details

Melero S., López-Garrido R., Madejón E., Murillo J.M., Vanderlinden K., Ordóñez R. & Moreno F. (2009) Long-term effects of conservation tillage on organic fractions in two soils in southwest of Spain. Agriculture, Ecosystems & Environment, 133, 68-74


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Soil: Use no tillage in arable fields Mediterranean Farmland

A replicated, randomized, controlled study in 1982–2008 on a rainfed wheat-sunflower-legume field near Seville, Spain (same study as (14)), found similar amounts of microbial biomass in soils with no tillage or conventional tillage. Soil organisms: Similar amounts of microbial biomass (measured as carbon) were found in soils with no tillage or conventional tillage (272–766 vs 314–378 mg C/kg soil). Methods: No tillage or conventional tillage was used on three plots each (15 x 18 m). A mouldboard plough and a cultivator (depths not reported) were used for conventional tillage, and crop residues were burned. A seed drill and herbicide were used for no tillage, and crop residues were retained. Herbicide was used on all plots. Wheat, sunflowers, and legumes were grown in rotation. Wheat was fertilized, but sunflowers and legumes were not. Soil samples were collected in March 2008 (three samples/plot, 400 g/soil core, 0–20 cm depth).

 

Soil: Use reduced tillage in arable fields Mediterranean Farmland

A replicated, randomized, controlled study in 1991–2008 on a rainfed wheat-sunflower-pea field near Seville, Spain (same study as (18)), found more soil organisms in plots with reduced tillage, compared  to conventional tillage. Soil organisms: More microbial biomass (measured as carbon) was found in soils with reduced tillage, compared to conventional tillage, in two of three comparisons (0–10 cm depth: 978–1,058 vs 806–814 mg C/kg soil). Methods: Reduced tillage or conventional tillage was used on three plots each (22 x 14 m), in 1991–2008. A chisel plough (25–30 cm depth, every two years) and a disc harrow (5–7 cm depth, every year) were used for reduced tillage. A mouldboard plough (25–30 cm depth), a cultivator (15–20 cm, 2–3 passes), and a disc harrow (15 cm) were used for conventional tillage (every year). Wheat, sunflowers, and peas were grown in rotation. Wheat was fertilized, but sunflowers and peas were not. In 1991–2003, crop residues were burned on plots with conventional tillage. Crop residues were retained and herbicides were used on plots with reduced tillage. Soil samples were collected in March 2008 (three samples/plot, 400 g/soil core, 0–20 cm depth).