Effects of N levels on land productivity and N2O emissions in maize-soybean relay intercropping.
J Sci Food Agric
; 104(14): 8823-8836, 2024 Nov.
Article
de En
| MEDLINE
| ID: mdl-38980001
ABSTRACT
BACKGROUND:
Relay intercropping of maize and soybean can improve land productivity. However, the mechanism behind N2O emissions in this practice remains unclear. A two-factor randomized block field trial was conducted to reveal the mechanism of N2O emissions in a full additive maize-soybean relay intercropping. Factor A was three cropping systems - that is, monoculture maize (Zea mays L.), monoculture soybean (Glycine max L. Merr.) and maize-soybean relay intercropping. Factor B was different N supply, containing no N, reduced N and conventional N. Differences in N2O emissions, soil properties, rhizosphere bacterial communities and yield advantage were evaluated.RESULTS:
The land equivalent ratio was 1.55-2.44, and the cumulative N2O emission ( C E N 2 O ) was notably lower by 60.2% in intercropping than in monoculture, respectively. Reduced N declined C E N 2 O without penalty on the yield advantages. The relay intercropping shifted soil properties - for example, soil organic matter, total N, NH 4 + and protease activity - and improved the soil microorganism community - for example, Proteobacteria and Acidobacteria. Intercropping reduced C E N 2 O by directly suppressing nirS- and amoA-regulated N2O generation during soil N cycling, or nirS- and amoA-mediated soil properties shifted to reduce C E N 2 O indirectly. Reduced N directly reduced C E N 2 O by decreasing soil N content and reducing soil microorganism activities to alleviate N2O produced in soil N cycling.CONCLUSION:
Conducting a full additive maize-soybean relay intercropping with reduced nitrogen supply provides a way to alleviate N2O emissions without the penalty on the yield advantage by changing rhizosphere bacterial communities and soil N cycling. © 2024 Society of Chemical Industry.Mots clés
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Sol
/
Microbiologie du sol
/
Glycine max
/
Bactéries
/
Zea mays
/
Azote
/
Protoxyde d'azote
Langue:
En
Journal:
J Sci Food Agric
/
J. sci. food agric
/
Journal of the science of food and agriculture
Année:
2024
Type de document:
Article
Pays d'affiliation:
Chine
Pays de publication:
Royaume-Uni