Abstract
Abstract Complementarity (CE) and selection effects (SE) have been either invoked to explain the positive diversity–productivity relationship in natural and semi‐natural ecosystems. Few studies have, however, separated selection and complementarity effects in economically valuable intercropping systems, which receive significant nutrient inputs throughout the growing season. We performed a 2‐year field experiment with five cropping systems (i.e. maize/peanut intercropping, maize/soybean intercropping, maize, peanut and soybean monocultures) under different combinations of nitrogen (N) and phosphorus (P) fertilization. Sequential harvest of subplots was performed five times during the growing season and the additive partitioning method was applied to determine complementarity and selection effects in the two intercropping systems. We found that the land equivalent ratio (LER) based on yield was greater than or close to 1 in both maize/soybean and maize/peanut intercropping systems, suggesting yield advantages in these intercropping systems compared to monocultures. The LER of the two intercropping systems without N fertilization was greater in 2018 than in 2017. Nitrogen fertilization reduced the LER of maize/soybean intercropping in 2018, and that of maize/peanut intercropping across 2 years. Nitrogen fertilization had much stronger effects on maize yield than on soybean or peanut yield. Intercropping increased maize yield but decreased soybean and peanut yield. The CE was more important for net biodiversity effects without N fertilization while the SE was more important with N fertilization in the two intercropping systems across 2 years. Phosphorus fertilization impacts on the LER and biodiversity effects were weaker compared to N fertilization. Finally, net biodiversity effects were greater at later growth stages within a growing season. Synthesis and applications . Our study demonstrates how yield advantages of species‐diverse intercropping systems can be maximized either through (a) CE in the absence of N fertilization thanks to complementarity in nutrient use between crops or (b) SE under N fertilization thanks to overyielding of highly productive species (i.e. maize). Yield advantages promoted by CE are more sustainable because they are associated with reduced chemical fertilizer use and greater monetary benefits to farmers. These findings have important implications for the design and management of species‐diverse intercropping food‐production systems.
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 12
Claim · model-written summary
The yield-based land equivalent ratio was greater than or close to 1 in both maize/soybean and maize/peanut intercropping systems.
Verbatim
e0“We found that the land equivalent ratio (LER) based on yield was greater than or close to 1 in both maize/soybean and maize/peanut intercropping systems”
Claim · model-written summary
Without N fertilization the LER of the two intercropping systems was greater in 2018 than in 2017.
Verbatim
t0“maize/legume intercropping systems”
e0“The LER of the two intercropping systems without N fertilization was greater in 2018 than in 2017”
Claim · model-written summary
Nitrogen fertilization reduced the LER of maize/soybean intercropping in 2018.
- Taxon
- maize/soybean intercroppinge0
- Treatment
- Nitrogen fertilizatione0
- Outcome
- LERe0
- Direction
- reducede0
- Qualifier
- in 2018e0
Not reportedComparator
Verbatim
e0“Nitrogen fertilization reduced the LER of maize/soybean intercropping in 2018, and that of maize/peanut intercropping across 2 years”
Claim · model-written summary
Nitrogen fertilization reduced the LER of maize/peanut intercropping across 2 years.
- Taxon
- maize/peanut intercroppinge0
- Treatment
- Nitrogen fertilizatione0
- Outcome
- LERe0
- Direction
- reducede0
- Qualifier
- across 2 yearse0
Not reportedComparator
Verbatim
e0“Nitrogen fertilization reduced the LER of maize/soybean intercropping in 2018, and that of maize/peanut intercropping across 2 years”
Claim · model-written summary
Nitrogen fertilization affected maize yield much more strongly than soybean or peanut yield.
- Treatment
- Nitrogen fertilizatione0
- Outcome
- maize yielde0
- Direction
- strongere0
- Comparator
- soybean or peanut yielde0
Zea maysOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrogen fertilization had much stronger effects on maize yield than on soybean or peanut yield”
Claim · model-written summary
Intercropping increased maize yield.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Intercropping increased maize yield but decreased soybean and peanut yield”
Claim · model-written summary
Intercropping decreased soybean and peanut yield.
- Taxon
- soybean and peanut
Arachis hypogaea
Glycine maxe0 - Treatment
- Intercroppinge0
- Outcome
- yielde0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Intercropping increased maize yield but decreased soybean and peanut yield”
Claim · model-written summary
The complementarity effect was more important for net biodiversity effects without N fertilization in the two intercropping systems across 2 years.
Verbatim
t0“maize/legume intercropping systems”
e0“The CE was more important for net biodiversity effects without N fertilization while the SE was more important with N fertilization in the two intercropping systems across 2 years”
Claim · model-written summary
The selection effect was more important for net biodiversity effects with N fertilization in the two intercropping systems across 2 years.
Verbatim
t0“maize/legume intercropping systems”
e0“The CE was more important for net biodiversity effects without N fertilization while the SE was more important with N fertilization in the two intercropping systems across 2 years”
Claim · model-written summary
Phosphorus fertilization had weaker impacts on the LER and biodiversity effects than N fertilization.
Verbatim
t0“maize/legume intercropping systems”
e0“Phosphorus fertilization impacts on the LER and biodiversity effects were weaker compared to N fertilization”
Claim · model-written summary
Net biodiversity effects were greater at later growth stages within a growing season.
Verbatim
t0“maize/legume intercropping systems”
e0“net biodiversity effects were greater at later growth stages within a growing season”
Claim · model-written summary
Yield advantages of the intercropping systems can be maximized through complementarity effects in the absence of N fertilization, or through selection effects under N fertilization.
Verbatim
t0“maize/legume intercropping systems”
e0“how yield advantages”
e1“CE in the absence of N fertilization thanks to complementarity in nutrient use between crops”
The same questions in other papers
intercropping · yield · Arachis hypogaea (peanut)Results differ
39 papers in the same direction as this paper · 79 in the opposite direction
- negative
- positive
- positive
115 papers more in this group
See all 119 papers →intercropping · yield · Glycine max (soybean)Positive and negative results
86 papers in the same direction as this paper · 131 in the opposite direction
- positive
- negative
- positive
214 papers more in this group
See all 218 papers →intercropping · yield · Zea mays (maize)Positive and negative results
612 papers in the same direction as this paper · 181 in the opposite direction · 40 reporting no difference from an alternative
- negative
- positive
- positive
830 papers more in this group
See all 834 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.