Divergence in the soil and rhizosphere microbial communities of monoculture and silvopastoral traditional C. dodecandra agroforestry systems in Yucatan, Mexico

Abstract

Numerous works have reported the impact on soil properties and microbial communities of intensive soil management, but very little is known about the impact caused by traditional agroforestry systems carried out by smallholders. To investigate whether the different smallholder's management between a monoculture plantation of Cordia dodecandra trees and a Silvopastoral system has led to a divergence in these ecosystems, soil properties, as well as soil and Cordia dodecandra rhizosphere microbial communities were analysed by MiSeq amplicon sequencing. The main findings were (i) Large variation in the soil properties of the Silvopastoral system suggests that it has a greater heterogeneity; (ii) Organic carbon, organic matter, carbonates, nitrogen, inorganic phosphorous and calcium, was significantly higher in the soil of the Silvopastoral system. (iii) The relative abundance of the major prokaryotic orders in soil and rhizospheres displayed small differences between the two agroforestry systems, and diversity indexes were slightly higher in the Silvopastoral system. (iv) The fungal orders Hypocreales and Pleosporales were more abundant in the Silvopastoral system than in the monoculture. Other evaluated parameters showed only minor or no difference. Thus, the main conclusion is that these soils have diverged in some properties and fungal orders, but not in their prokaryotic communities. To our knowledge, this is the first report on the divergence in soil properties and microbiota of these two extended smallholder agroforestry systems and therefore can serve as reference for future works.