Skip to main content
ARS Home » Plains Area » Fort Collins, Colorado » Center for Agricultural Resources Research » Soil Management and Sugarbeet Research » Research » Publications at this Location » Publication #420162
Research Project: Agricultural Management for Long-Term Sustainability and Soil Health

Location: Soil Management and Sugarbeet Research

Title: Soil carbon allocation, composition, and sequestration changes induced by cropping diversification in tropical systems

Author
item LOCATELLI, JORGE - Federal University Of Sao Paulo
item SANTOS, RAFAEL - Colorado State University
item TENELLI, SARAH - Brazilian Biorenewable National Laboratory
item SOARES, MATHEUS - Federal University Of Sao Paulo
item Del Grosso, Stephen
item Stewart, Catherine
item POPIN, GUSTAVO - Federal University Of Sao Paulo
item BERTOL, FELIPE - Universidade Federal Do Mato Grosso Do Sul
item CARVALHO, JOAO - Brazilian Biorenewable National Laboratory
item CHERUBIN, MAURICIO - Federal University Of Sao Paulo
item CERRI, CARLOS - Federal University Of Sao Paulo

Submitted to: Soil and Tillage Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/16/2025
Publication Date: 1/26/2025
Citation: Locatelli, J.L., Santos, R.S., Tenelli, S., Soares, M.B., Del Grosso, S.J., Stewart, C.E., Popin, G.V., Bertol, F.D., Carvalho, J.L., Cherubin, M.R., Cerri, C.E. 2025. Soil carbon allocation, composition, and sequestration changes induced by cropping diversification in tropical systems. Soil and Tillage Research. 248. Article e106464. https://doi.org/10.1016/j.still.2025.106464.
DOI: https://doi.org/10.1016/j.still.2025.106464

Interpretive Summary: Physical protection of carbon (C) inside soil particles can store C and improve soil health. However, little is known about how cropping diversification strategies affect C protection in tropical soils. We investigated how crop rotation complexity and cover crops affect soil properties in Mato Grosso, Brazil. Compared to typical soybean-maize cropping, more complex systems that included cover crops had higher soil C and nutrient levels. Results revealed that cropping diversification is an effective strategy for increasing C protection and enhancing heath of tropical soils.

Technical Abstract: Physical protection by carbon (C) occlusion inside soil aggregates is assumed to be a key mechanism of C stabilization. Nevertheless, little is known about how cropping diversification strategies affect C allocation and protection in soil aggregates and their stability, especially in highly weathered tropical soils. This study evaluated how cropping diversification strategies based on cover crops and no-tillage affect soil organic matter (SOM) storage and aggregation in a tropical clayey Oxisol. Changes in soil C and nitrogen (N) stocks, soil aggregate stability, C allocation within aggregates, and C speciation within aggregate classes using spectroscopy analysis were quantified. Soil C and N stocks under the most complex crop systems with cover crops increased by ~20% and 29%, respectively, compared to soybean-maize double cropping. The systems including cover crops also increased soil aggregate stability, doubling large macroaggregation in the 5-10 and 10-20 cm depths compared to the soybean-maize double cropping. Increased aggregation under cover crops enhanced C contents within aggregates, i.e., ~48%, 32%, and 34% higher for large macroaggregates, macroaggregates, and microaggregates, respectively, compared to soybean-maize double cropping (average considering different layers and cover cropping systems). Spectroscopy analysis showed that the diverse cropping systems increased the aromatic C fraction (i.e., C=C/C–C) in large macroaggregates from the 0-5 cm layer while reducing oxidized groups, i.e., C=O/O–C=O and C–O. Overall, results revealed that cropping diversification is an effective strategy for increasing soil aggregate stability and physical protection of C (especially aromatic), and therefore can promote C storage in tropical soils.