Abstract
Chemical fertilizers (CF) are the major input on arable farms in Nigeria. Current increasing rate of nutrient depletion in CF treated soils calls for the need to study their reactions in soils. To achieve this, three CF based treatments, namely NPK 15:15:15 applied at 40 kg P2O5 ha-1, Urea applied at 20 kg N ha-1 mixed with Single superphosphate at 40 kg P2O5 ha-1, and single superphosphate at 40 kg P2O5 ha-1 mixed with Gliricidia sepium leaves at 20 kg N ha-1 were studied. Sole lime (CaCO3) at 1 Mg ha-1 and a plot that received no amendment were compared. Cowpea was grown for two consecutive cropping seasons in 2012 and 2013 on the treated fields. The results indicated that CF reduced soil pH from initial 4.8 to 4.0. The NPK 15:15:15 fertilizer was the most severe of the CF tested, removing up to 133% alkalinity from the soil relative to lime. The NPK 15:15:15 reduced calcium saturation (from 25% to 21%) and magnesium saturation (from 12% to 8.3%) and increased acidity saturation (from 53% to 66%) with significant reductions in organic carbon content (from 13.2 g kg-1 to 11.0 g kg-1). Precaution including co-application of CF with organic materials such as Gliricidia sepium leaves can benefit for the soils.
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Claims 7
Claim · model-written summary
Chemical fertilizers reduced soil pH from 4.8 to 4.0.
- Taxon
- Cowpea
Vigna unguiculatat0 - Treatment
- CFe0
- Outcome
- soil pHe0
- Direction
- reducede0
- Value
- 4.0e0
- Comparator
- initial 4.8e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“CF reduced soil pH from initial 4.8 to 4.0”
t0“Cowpea”
Claim · model-written summary
NPK 15:15:15 removed up to 133% soil alkalinity relative to lime.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15 fertilizere0
- Outcome
- alkalinity from the soile0
- Direction
- removinge0
- Value
- 133%e0
- Comparator
- limee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The NPK 15:15:15 fertilizer was the most severe of the CF tested, removing up to 133% alkalinity from the soil relative to lime”
t0“Cowpea”
Claim · model-written summary
NPK 15:15:15 reduced calcium saturation from 25% to 21%.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e0
- Outcome
- calcium saturatione0
- Direction
- reducede0
- Value
- 21%e0
- Comparator
- 25%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The NPK 15:15:15 reduced calcium saturation (from 25% to 21%)”
t0“Cowpea”
Claim · model-written summary
NPK 15:15:15 reduced magnesium saturation from 12% to 8.3%.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e1
- Outcome
- magnesium saturatione0
- Direction
- reducede1
- Value
- 8.3%e0
- Comparator
- 12%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“magnesium saturation (from 12% to 8.3%)”
e1“The NPK 15:15:15 reduced calcium saturation”
t0“Cowpea”
Claim · model-written summary
NPK 15:15:15 increased acidity saturation from 53% to 66%.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e0
- Outcome
- acidity saturatione0
- Direction
- increasede0
- Value
- 66%e0
- Comparator
- 53%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The NPK 15:15:15 reduced calcium saturation (from 25% to 21%) and magnesium saturation (from 12% to 8.3%) and increased acidity saturation (from 53% to 66%)”
t0“Cowpea”
Claim · model-written summary
NPK 15:15:15 significantly reduced soil organic carbon from 13.2 to 11.0 g kg-1.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e0
- Outcome
- organic carbon contente0
- Direction
- reductionse0
- Value
- 11.0 g kg-1e0
- Comparator
- 13.2 g kg-1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The NPK 15:15:15 reduced calcium saturation (from 25% to 21%) and magnesium saturation (from 12% to 8.3%) and increased acidity saturation (from 53% to 66%) with significant reductions in organic carbon content (from 13.2 g kg-1 to 11.0 g kg-1)”
t0“Cowpea”
Claim · model-written summary
The authors recommend coapplying chemical fertilizers with organic materials such as Gliricidia leaves for soil benefit.
- Taxon
- CowpeaVigna unguiculatat0
- Outcome
- co-application of CF with organic materials such as Gliricidia sepium leaves can benefit for the soilse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“co-application of CF with organic materials such as Gliricidia sepium leaves can benefit for the soils”
t0“Cowpea”
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