A meta-analysis addressing the effects of eucalypt plantations on soil invertebrate density and diversity

Eucalypt plantations may have negative consequences on soil properties, yet a comprehensive understanding of their impact on soil invertebrate communities is lacking. This knowledge gap constrains our ability to unravel the potential effects of these fast-growing plantations on soil functioning. Hence, to analyze the overall impact of eucalypt plantations on soil invertebrates and to determine the main factors influencing these effects, we conducted a meta-analysis of studies comparing eucalypt plantations with different land use types (i.e. native forests, other forestry plantations, croplands, grasslands, integrated production systems, and invasive copses). We assessed their effects on both the density (analyzing 26 studies with 143 comparisons) and diversity (examining 14 studies with 168 comparisons) of soil invertebrate communities. The impact of eucalypt plantations on the density and diversity of soil invertebrate communities did not show statistically significant differences when considering all land use types together. However, the effects of eucalypt plantations on soil invertebrate density and diversity varied based on the specific land use types considered for comparison. The density was lower in eucalypt plantations relative to other forestry plantations but higher than in grasslands and integrated production systems. Contrarily, diversity was lower in eucalypt plantations compared to native forests but higher compared to other forestry plantations. Furthermore, the impacts of eucalypt plantations on soil invertebrates relative to other forestry plantations were influenced by factors such as the type of other forestry plantation (angiosperms versus gymnosperms), mean annual temperature, and annual precipitation of the study sites. These findings suggest that the effects of eucalypt plantations on soil invertebrate communities are context-specific and heavily influenced by the diverse characteristics of the different land use types considered for comparison. Taking into account the specific management practices and environmental conditions within eucalypt plantations and other land use types can provide insight into how alterations in land cover affect soil invertebrate communities.