Abstract
Abstract Legumes have been shown to enhance bioavailability of phosphorus (P) from sparingly soluble pools, yet this functional trait remains underutilized in agriculture, and is untested at decadal scales. Management and legume presence effects on temporal soil properties were evaluated in a 17-year field crop experiment using soil samples collected in 1992, 2000 and 2006. Management systems compared included: (1) conventional corn–soybean–wheat rotation (C–S–W), (2) organic (C–S–W+red clover), (3) alfalfa and (4) early successional field. To evaluate the effects of long-term management versus recent management (residues and P fertilizer) on P and bio-availability to soybean, subplots of soybean were established with and without P-fertilizer (30 kg P ha −1 ), and compared to subplots and main plot with the long-term system. We evaluated soil properties (C, total P, Bray extractable inorganic P, particulate organic matter phosphorus) and soybean P uptake, biomass and yield. Recent fertilizer P inputs had no detectable influence on soil P, and total soil P stayed stable at ~350 mg P kg −1 , whereas inorganic P (Pi) declined from an initial value of 54 to an average of 35 mg P kg −1 . A P balance was constructed and showed a net loss of −96.7 kg P ha −1 yr −1 for the organic system, yet Bray-Pi and soybean P uptake were maintained under organic production at similar levels to the conventional, fertilized system. Particulate organic matter P was 57, 82 and 128% higher in organic, alfalfa and successional treatments, respectively, compared to conventional. A similar pattern was observed for soil C, soybean yield and bioavailable P, which were 20–50% higher in the organic, alfalfa and successional systems relative to conventional. This study provides evidence that long-term management history influences bioavailability of P.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. 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 13
Claim · model-written summary
Recent fertilizer phosphorus inputs had no detectable influence on soil phosphorus.
Not reportedTaxonComparator
Verbatim
e0“Recent fertilizer P inputs had no detectable influence on soil P”
Claim · model-written summary
Total soil phosphorus remained stable at approximately 350 mg P kg −1.
Not reportedTaxon
Verbatim
e0“total soil P stayed stable at ~350 mg P kg −1”
Claim · model-written summary
Inorganic phosphorus declined from 54 to an average of 35 mg P kg −1.
- Outcome
- inorganic P (Pi)e0
- Direction
- declinede0
- Value
- 35 mg P kg −1e0
- Qualifier
- from an initial value of 54e0
Not reportedTaxon
Verbatim
e0“inorganic P (Pi) declined from an initial value of 54 to an average of 35 mg P kg −1”
Claim · model-written summary
The organic system had a net phosphorus loss of −96.7 kg P ha −1 yr −1.
Not reportedTaxon
Verbatim
e0“A P balance was constructed and showed a net loss of −96.7 kg P ha −1 yr −1 for the organic system”
Claim · model-written summary
Organic production maintained Bray-Pi at levels similar to the conventional fertilized system.
- Treatment
- organic productione0
- Outcome
- Bray-Pie0
- Direction
- similar levelse0
- Comparator
- conventional, fertilized systeme0
Not reportedTaxon
Verbatim
e0“Bray-Pi and soybean P uptake were maintained under organic production at similar levels to the conventional, fertilized system”
Claim · model-written summary
Organic production maintained soybean phosphorus uptake at levels similar to the conventional fertilized system.
- Taxon
- soybean
Glycine maxe0 - Treatment
- organic productione0
- Outcome
- P uptakee0
- Direction
- similar levelse0
- Comparator
- conventional, fertilized systeme0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Bray-Pi and soybean P uptake were maintained under organic production at similar levels to the conventional, fertilized system”
Claim · model-written summary
Particulate organic matter phosphorus was 57% higher under organic management than conventional management.
- Treatment
- organice0
- Outcome
- Particulate organic matter Pe0
- Direction
- highere0
- Value
- 57e0
- Comparator
- conventionale0
Not reportedTaxon
Verbatim
e0“Particulate organic matter P was 57, 82 and 128% higher in organic, alfalfa and successional treatments, respectively, compared to conventional.”
Claim · model-written summary
Particulate organic matter phosphorus was 82% higher under alfalfa than conventional management.
- Treatment
- alfalfae0
- Outcome
- Particulate organic matter Pe0
- Direction
- highere0
- Value
- 82e0
- Comparator
- conventionale0
Not reportedTaxon
Verbatim
e0“Particulate organic matter P was 57, 82 and 128% higher in organic, alfalfa and successional treatments, respectively, compared to conventional.”
Claim · model-written summary
Particulate organic matter phosphorus was 128% higher under successional management than conventional management.
- Treatment
- successionale0
- Outcome
- Particulate organic matter Pe0
- Direction
- highere0
- Value
- 128%e0
- Comparator
- conventionale0
Not reportedTaxon
Verbatim
e0“Particulate organic matter P was 57, 82 and 128% higher in organic, alfalfa and successional treatments, respectively, compared to conventional.”
Claim · model-written summary
Organic management had soil carbon, soybean yield and bioavailable phosphorus 20–50% higher than conventional management.
- Taxon
- soybeanGlycine maxe0
- Treatment
- organice0
- Outcome
- soil C, soybean yield and bioavailable Pe0
- Direction
- highere0
- Value
- 20–50%e0
- Comparator
- conventionale0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A similar pattern was observed for soil C, soybean yield and bioavailable P, which were 20–50% higher in the organic, alfalfa and successional systems relative to conventional.”
Claim · model-written summary
Alfalfa management had soil carbon, soybean yield and bioavailable phosphorus 20–50% higher than conventional management.
- Taxon
- soybeanGlycine maxe0
- Treatment
- alfalfae0
- Outcome
- soil C, soybean yield and bioavailable Pe0
- Direction
- highere0
- Value
- 20–50%e0
- Comparator
- conventionale0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A similar pattern was observed for soil C, soybean yield and bioavailable P, which were 20–50% higher in the organic, alfalfa and successional systems relative to conventional.”
Claim · model-written summary
Successional management had soil carbon, soybean yield and bioavailable phosphorus 20–50% higher than conventional management.
- Taxon
- soybeanGlycine maxe0
- Treatment
- successionale0
- Outcome
- soil C, soybean yield and bioavailable Pe0
- Direction
- highere0
- Value
- 20–50%e0
- Comparator
- conventionale0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A similar pattern was observed for soil C, soybean yield and bioavailable P, which were 20–50% higher in the organic, alfalfa and successional systems relative to conventional.”
Claim · model-written summary
The study provides evidence that long-term management history influences phosphorus bioavailability.
Not reportedTaxonComparatorDirection
Verbatim
e0“This study provides evidence that long-term management history influences bioavailability of P.”
The same questions in other papers
Medicago sativa · yield · Glycine max (soybean)Positive and negative results
4 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- negative
- positive
3 papers more in this group
See all 7 papers →cultivation system · nutrient: content · Glycine max (soybean)Positive and negative results
1 paper in the same direction as this paper · 3 reporting no difference from an alternative
- positive
- positive
- positive
1 paper more in this group
See all 5 papers →cultivation system · yield · Glycine max (soybean)Positive and negative results
34 papers in the same direction as this paper · 25 in the opposite direction · 3 reporting no difference from an alternative
- negative
- negative
- negative
59 papers more in this group
See all 63 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.