Abstract
Under semiarid Mediterranean conditions irrigated maize ( Zea mays L.) has been associated with nitrate pollution of surface water and groundwater. Cover crops grown during the intercrop period of maize could reduce N leaching. A 2‐yr experiment was conducted in drainage lysimeters with three cover crops: barley ( Hordeum vulgare L), winter rape ( Brassica rapa L.), or common vetch ( Vicia sativa L.). Bare soil was used as control treatment. Maize was fertilized with 300 kg ha −1 N in the control, and this amount was reduced after a cover crop according to the N content in the aboveground cover crop biomass. Barley and winter rape biomass had a higher N content than vetch (130–170 vs. 50 kg ha −1 ). The vetch treatment did not reduce N leaching or affect maize yield. The barley and winter rape treatments reduced N leaching by 80% compared to the control (25 kg ha −1 yr −1 ) mainly due to a reduction of NO 3 –N concentration in drainage. Maize yield was reduced by 2.7 Mg ha −1 after barley and winter rape but still high (≈14 Mg ha −1 ). This reduction was due to an N deficiency caused by lower soil N in spring after the cover crop and insufficient N mineralization and/or lack of synchronization with maize N uptake. To use nonlegume winter cover crops to reduce N leaching in monoculture maize it is necessary to consider that N mineralization may not be sufficient to fulfill maize N requirements and N fertilizer adjustment tools should be developed.
Abstract from the paper’s OpenAlex record; open copy licensed other-oa. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 10
Claim · model-written summary
Barley biomass had higher N content than vetch biomass.
- Taxon
- barley
.jpg?width=60)
Hordeum vulgaree0 - Outcome
- N contente0
- Direction
- highere0
- Value
- 130–170e0
- Qualifier
- 50 kg ha −1e0
- Comparator
- vetche0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“Barley and winter rape biomass had a higher N content than vetch (130–170 vs. 50 kg ha −1 ).”
Claim · model-written summary
Winter rape biomass had higher N content than vetch biomass.
- Taxon
- winter rape
_Brassica_napus_-_Habit.jpg?width=60)
Brassica napuse0 - Outcome
- N contente0
- Direction
- highere0
- Value
- 130–170e0
- Qualifier
- 50 kg ha −1e0
- Comparator
- vetche0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
_Brassica_napus_-_Habit.jpg?width=500)
Verbatim
e0“Barley and winter rape biomass had a higher N content than vetch (130–170 vs. 50 kg ha −1 ).”
Claim · model-written summary
Vetch cover cropping did not reduce N leaching.
Zea maysNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The vetch treatment did not reduce N leaching or affect maize yield.”
Claim · model-written summary
Vetch cover cropping did not affect maize yield.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The vetch treatment did not reduce N leaching or affect maize yield.”
Claim · model-written summary
barley cover cropping reduced N leaching by 80% versus control.
- Treatment
- barleye0
- Outcome
- N leachinge0
- Direction
- reducede0
- Value
- 80%e0
- Qualifier
- 25 kg ha −1 yr −1e0
- Comparator
- controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The barley and winter rape treatments reduced N leaching by 80% compared to the control (25 kg ha −1 yr −1 ) mainly due to a reduction of NO 3 –N concentration in drainage.”
t0“Maize”
Claim · model-written summary
winter rape cover cropping reduced N leaching by 80% versus control.
- Treatment
- winter rapee0
- Outcome
- N leachinge0
- Direction
- reducede0
- Value
- 80%e0
- Qualifier
- 25 kg ha −1 yr −1e0
- Comparator
- controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The barley and winter rape treatments reduced N leaching by 80% compared to the control (25 kg ha −1 yr −1 ) mainly due to a reduction of NO 3 –N concentration in drainage.”
t0“Maize”
Claim · model-written summary
Maize yield declined by 2.7 Mg ha −1 after barley.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maize yield was reduced by 2.7 Mg ha −1 after barley and winter rape but still high (≈14 Mg ha −1 ).”
Claim · model-written summary
Maize yield declined by 2.7 Mg ha −1 after winter rape.
- Treatment
- winter rapee0
- Outcome
- Maize yielde0
- Direction
- reducede0
- Value
- 2.7 Mg ha −1e0
- Qualifier
- ≈14 Mg ha −1e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maize yield was reduced by 2.7 Mg ha −1 after barley and winter rape but still high (≈14 Mg ha −1 ).”
Claim · model-written summary
The authors attribute lower maize yield after cover cropping to N deficiency.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This reduction was due to an N deficiency caused by lower soil N in spring after the cover crop and insufficient N mineralization and/or lack of synchronization with maize N uptake.”
t0“Maize”
Claim · model-written summary
The authors recommend developing N fertilizer adjustment tools for maize after nonlegume cover crops.
- Outcome
- N fertilizer adjustment tools should be developede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“To use nonlegume winter cover crops to reduce N leaching in monoculture maize it is necessary to consider that N mineralization may not be sufficient to fulfill maize N requirements and N fertilizer adjustment tools should be developed.”
The same questions in other papers
Hordeum vulgare · yield · Zea mays (maize)Positive and negative results
7 in the opposite direction
- positive
- positive
- positive
4 papers more in this group
See all 8 papers →Brassica napus · yield · Zea mays (maize)Positive and negative results
2 papers in the same direction as this paper · 5 in the opposite direction
- positive
- positive
- positive
4 papers more in this group
See all 8 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.