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Individual study: Nitrogen oxide emissions from an irrigated maize crop amended with treated pig slurries and composts in a Mediterranean climate

Published source details

Meijide A., Díez J.a., Sánchez-Martín L., López-Fernández S. & Vallejo a. (2007) Nitrogen oxide emissions from an irrigated maize crop amended with treated pig slurries and composts in a Mediterranean climate. Agriculture, Ecosystems & Environment, 121, 383-394


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

Crop production: Add slurry to the soil Mediterranean Farmland

A replicated, randomized, controlled study in 2009 in a rainfed barley field in Spain found higher crop yields in plots with added slurry, compared to plots without it. Crop yield: Higher barley yields were found in plots with added slurry, compared to plots without it, in one of two comparisons (1,508 vs 972 kg/ha). Implementation options: Similar barley yields were found in plots with untreated slurry or digested slurry (1,125 vs 1,508 kg/ha). Methods: Plots (30 m2) had no fertilizer or pig slurry (anaerobically-digested or untreated), which was applied in January 2006 (125 kg N/ha; three plots for each) and incorporated into the soil (0–5 cm depth) using a roto-cultivator. Phosphate and potassium (75 and 40 kg/ha, respectively) were added to all plots.

 

Soil: Add slurry to the soil Mediterranean Farmland

A replicated, randomized, controlled study in 2004 in a maize field in the Jarama river basin, Spain, found higher nitrous oxide emissions from soils fertilized with slurry, compared to unfertilized soils. Greenhouse gases: Higher nitrous oxide emissions were found in soils with slurry, compared to unfertilised soils (untreated pig slurry: 8.3 vs 6.0; digested pig slurry: 7.7 vs 6.0 kg N/ha). Implementation options: No difference in nitrous oxide emissions was found between soils fertilized with digested pig slurry or untreated pig slurry (7.7 vs 8.3 kg N/ha). Methods: There were three plots (40 m2) for each of two treatments (untreated pig slurry or anaerobically digested thin fraction of pig slurry) and one control (no slurry). Both slurries were applied at a rate of 175 kg available N/ha. Nitrous oxide was measured in closed chambers (two chambers/plot, one within a maize row, one between rows; 35 cm diameter, 23 cm height; one sample/week, April-September).

 

Soil: Use organic fertilizer instead of inorganic Mediterranean Farmland

A replicated, randomized, controlled study in 2004 in a maize field in the Jarama river basin, Spain, found similar greenhouse-gas emissions in soils with organic or inorganic fertilizer. Greenhouse gases: No difference in nitrous oxide emissions was found in soils fertilized with pig slurry, compared to soils fertilized with urea (untreated pig slurry: 8.3 vs 8.6 kg N/ha; digested pig slurry: 7.7 vs 8.6). Methods: There were three plots (40 m2) for each of two organic fertilizers (anaerobically digested thin fraction of pig slurry or untreated pig slurry) and one mineral fertilizer (urea, which was a mineral fertilizer in this study, but urea is also produced from animal waste). Slurries were applied at a rate of 175 kg available N/ha. Urea was applied at a rate of 50 kg N/ha. Soils were cultivated to a depth of 5 cm to incorporate the fertilizers. Nitrous oxide was measured in closed chambers (two chambers/plot, one within a maize row, one between rows; 35 cm diameter, 23 cm height; one sample/week, April–September).

 

Crop production: Use organic fertilizer instead of inorganic Mediterranean Farmland

A replicated, randomized, controlled study in 2009 in a rainfed barley field in Spain found similar crop yields in plots with organic or inorganic fertilizer. Crop yield: Similar crop yields were found in plots with organic or inorganic fertilizer (1,032–1,508 vs 1,061 kg/ha). Methods: Plots (30 m2) had no fertilizer, organic fertilizer (pig slurry, anaerobically-digested pig slurry, municipal solid waste, or composted crop residue with sludge), or inorganic fertilizer (urea), which was applied in January 2006 (125 kg N/ha; three plots for each fertilizer) and incorporated into the soil (0–5 cm depth) using a roto-cultivator. Phosphate and potassium (75 and 40 kg/ha, respectively) were added to all plots.

 

Soil: Add compost to the soil Mediterranean Farmland

A replicated, randomized, controlled study in 2004 in a maize field in the Jarama river basin, Spain, found no difference in greenhouse-gas emissions between soils with or without added compost. Greenhouse gases: No difference in nitrous oxide emissions was found between soils with or without added compost (composted pig slurry: 9.3 vs 8.6 kg N/ha; composted municipal solid waste 7.1 vs 8.6). Methods: There were three plots (40 m2) for each of two treatments (composted solid fraction of pig slurry or composted municipal solid waste, both with urea) and one control (urea only). Urea was applied at a rate of 50 kg N/ha. Both composts were applied at a rate of 175 kg available N/ha. Soils were cultivated to a depth of 5 cm to incorporate the fertilizers. Nitrous oxide was measured in closed chambers (two chambers/plot, one within a maize row, one between rows, 35 cm diameter, 23 cm height, one sample/week, April–September).