oil aggregates profoundly impact soil sustainability and crop productivity, and they are influenced by complexinteractions between minerals and organics. This study aimed to elucidate the alterations in mineralogy and...oil aggregates profoundly impact soil sustainability and crop productivity, and they are influenced by complexinteractions between minerals and organics. This study aimed to elucidate the alterations in mineralogy and soilorganic carbon(SOC) following long-term green manure incorporation and the effect on soil aggregates. Based on 5-and 36-year field experiments, surface soil samples(0–20 cm) were collected from Alfisol and Ferrisol soilssubjected to rice–rice–winter fallow(CK) and rice–rice–Chinese milk vetch(MV) treatments to investigate aggregatestability, mineralogy, SOC composition, and soil microstructural characteristics. The results showed that high clay-content Ferrisol exhibited greater aggregate stability than low clay-content Alfisol. The phyllosilicates in Alfisolprimarily comprised illite and vermiculite, whereas those in Ferrisol with high-content free-form Fe oxides(Fed) weredominated by kaolinite. Additionally, the clay fraction in Ferrisol contained more aromatic-C than the clay fraction inAlfisol. The 36-year MV incorporation significantly increased the Ferrisol macroaggregate stability(9.57–13.37%),and it also facilitated the transformation of vermiculite into kaolinite and significantly increased the clay, Fed, and aromatic-C contents in Ferrisol. Backscattered electron(BSE)-scanning electron microscopy/energy dispersive X-ray spectroscopy(SEM/EDS) revealed a compact aggregate structure in Ferrisol with co-localization of Feoxides and kaolinite. Moreover, the partial least path model(PLS-PM) revealed that clay content directly improvedmacroaggregate stability, and that kaolinite and Fed positively and directly affected clay or indirectly modulated clay formation by increasing the aromatic-C levels. Overall, long-term MV incorporation promotes clay aggregation by affecting mineral transformation to produce more kaolinite and Fe oxides and retain aromatic-C, and it ultimately improves aggregate stability.展开更多
基金supported by the National Natural Science Foundation of China (41977020)the China Agriculture Research System of MOF and MARA (CARS22)。
文摘oil aggregates profoundly impact soil sustainability and crop productivity, and they are influenced by complexinteractions between minerals and organics. This study aimed to elucidate the alterations in mineralogy and soilorganic carbon(SOC) following long-term green manure incorporation and the effect on soil aggregates. Based on 5-and 36-year field experiments, surface soil samples(0–20 cm) were collected from Alfisol and Ferrisol soilssubjected to rice–rice–winter fallow(CK) and rice–rice–Chinese milk vetch(MV) treatments to investigate aggregatestability, mineralogy, SOC composition, and soil microstructural characteristics. The results showed that high clay-content Ferrisol exhibited greater aggregate stability than low clay-content Alfisol. The phyllosilicates in Alfisolprimarily comprised illite and vermiculite, whereas those in Ferrisol with high-content free-form Fe oxides(Fed) weredominated by kaolinite. Additionally, the clay fraction in Ferrisol contained more aromatic-C than the clay fraction inAlfisol. The 36-year MV incorporation significantly increased the Ferrisol macroaggregate stability(9.57–13.37%),and it also facilitated the transformation of vermiculite into kaolinite and significantly increased the clay, Fed, and aromatic-C contents in Ferrisol. Backscattered electron(BSE)-scanning electron microscopy/energy dispersive X-ray spectroscopy(SEM/EDS) revealed a compact aggregate structure in Ferrisol with co-localization of Feoxides and kaolinite. Moreover, the partial least path model(PLS-PM) revealed that clay content directly improvedmacroaggregate stability, and that kaolinite and Fed positively and directly affected clay or indirectly modulated clay formation by increasing the aromatic-C levels. Overall, long-term MV incorporation promotes clay aggregation by affecting mineral transformation to produce more kaolinite and Fe oxides and retain aromatic-C, and it ultimately improves aggregate stability.
