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 fertilisers reduced soil pH from 4.8 to 4.0.
- Taxon
- Cowpea
Vigna unguiculatat0 - Treatment
- CFe1
- Outcome
- soil pHe1
- Direction
- reducede1
- Value
- from initial 4.8 to 4.0e1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Effects on Cowpea Performance”
e1“The results indicated that CF reduced soil pH from initial 4.8 to 4.0”
Claim · model-written summary
NPK 15:15:15 removed up to 133% of the soil alkalinity relative to lime.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e2
- Outcome
- alkalinitye2
- Direction
- removinge2
- Value
- 133%e2
- Comparator
- limee2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Effects on Cowpea Performance”
e2“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”
Claim · model-written summary
NPK 15:15:15 reduced soil calcium saturation from 25% to 21%.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e3
- Outcome
- calcium saturatione3
- Direction
- reducede3
- Value
- from 25% to 21%e3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Effects on Cowpea Performance”
e3“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%)”
Claim · model-written summary
NPK 15:15:15 reduced soil magnesium saturation from 12% to 8.3%.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e3
- Outcome
- magnesium saturatione3
- Direction
- reducede3
- Value
- from 12% to 8.3%e3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Effects on Cowpea Performance”
e3“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%)”
Claim · model-written summary
NPK 15:15:15 increased soil acidity saturation from 53% to 66%.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e3
- Outcome
- acidity saturatione3
- Direction
- increasede3
- Value
- from 53% to 66%e3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Effects on Cowpea Performance”
e3“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%)”
Claim · model-written summary
NPK 15:15:15 significantly reduced soil organic carbon content from 13.2 to 11.0 g per kg.
- Taxon
- CowpeaVigna unguiculatat0
- Treatment
- NPK 15:15:15e3
- Outcome
- organic carbon contente4
- Direction
- reductionse4
- Value
- from 13.2 g kg-1 to 11.0 g kg-1e4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Effects on Cowpea Performance”
e3“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%)”
e4“with significant reductions in organic carbon content (from 13.2 g kg-1 to 11.0 g kg-1)”
Claim · model-written summary
Co-application of chemical fertilisers with organic materials such as Gliricidia sepium leaves can benefit soils.
- Taxon
- CowpeaVigna unguiculatat0
- Outcome
- co-application of CF with organic materialse5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Effects on Cowpea Performance”
e5“Precaution including co-application of CF with organic materials such as Gliricidia sepium leaves can benefit for the soils”
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