Abstract:
We measured the content and soil physicochemical properties of waterstable aggregates and the content of organic carbon from five rubberbased (Hevea brasiliensis) agroforestry ecosystems with different interplants (Camellia sinensis, Theobroma cacao, Flemingia macrophylla, Coffea arabica,and Dracaena americana), one rubber monoculture, and tropical rain forest in Xishuangbanna, southwest China. The results showed that when compared with tropical rain forest,the content of >5 mm and >025 mm waterstable aggregates collected from rubber monoculture significantly decreased, Meanwhile, the weight diameter (WMD) decreased by 10320%, and PAD025 increased by 36 times. When compared to rubber monoculture, agroforestry ecosystems displayed higher levels of SOC content, with the increased level in the range of 53%-6969%. As to the content of soil organic carbon in the aggregates, it was discovered that the smaller the aggregates were, the lower the soil organic carbon content was. Soil physicochemical properties(e.g., EC, bulk density and porosity)varied significantly among different sampling sites, whereas bulk density and porosity were both significantly related to the content of >025 mm and >5 mm waterstable aggregates and WMD. The above results showed that soil quality has been improved in rubberbased agroforestry ecosystems in comparison to rubber monocultures.