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Land use changes in the Amazon region strongly impact soil macroinvertebrate communities, which are recognized as major drivers of soil functions ( Lavelle et al., 2006 ). To explore these relations, we tested the hypotheses that (i) soil macrofauna communities respond to landscape changes and (ii) soil macrofauna and ecosystem services are linked. We conducted a survey of macrofauna communities and indicators of ecosystem services at 270 sites in southern Colombia (department of Caqueta) and northern Brazil (state of Pará), two areas of the Amazon where family agriculture dominates. Sites represented a variety of land use types: forests, fallows, annual or perennial crops, and pastures. At each site we assessed soil macroinvertebrate density (18 taxonomic units) and the following ecosystem service indicators: soil and aboveground biomass carbon stock; water infiltration rate; aeration, drainage and water storage capacities based on pore-size distribution; soil chemical fertility; and soil aggregation. Significant covariation was observed between macrofauna communities and landscape metric data (co-inertia analysis: RV = 0.30, p < 0.01, Monte Carlo test) and between macrofauna communities and ecosystem service indicators (co-inertia analysis: RV = 0.35, p < 0.01, Monte Carlo test). Points located in pastures within 100 m of forest had greater macrofauna density and diversity than those located in pastures with no forest within 100 m (Wilcoxon rank sum test, p < 0.01). Total macroinvertebrate density was significantly correlated with macroporosity ( r 2 = 0.42, p < 0.01), as was the density of specific taxonomic groups: Chilopoda ( r 2 = 0.43, p < 0.01), Isoptera ( r 2 = 0.30, p < 0.01), Diplopoda ( r 2 = 0.31, p < 0.01), and Formicidae ( r 2 = 0.13, p < 0.01). Total macroinvertebrate density was also significantly correlated with available soil water ( r 2 = 0.38, p < 0.01) as well as other soil-service indicators (but with r 2 < 0.10). Results demonstrate that landscape dynamics and composition affect soil macrofauna communities, and that soil macrofauna density is significantly correlated with soil services in deforested Amazonia, indicating that soil macrofauna have an engineering and/or indicator function. [ABSTRACT FROM AUTHOR]

The global demand for different land-use practice commodities in the Amazonia is growing, and this region is increasingly affected by the impacts of land management. The aim of this study was to evaluate the influence of land-use intensification on soil spider assemblages from six different land-use systems in Colombia and Brazil. The systems were fallows after crops and pastures, forest, crops, pastures and plantations. Spider species richness and density decreased with increasing farming management intensity. A principal component analysis (PCA) showed forests and fallows were separated from systems with stronger anthropogenic soil disturbance. The relationships of ten spider guilds differed significantly between land-uses, suggesting that they can be a reliable parameter for studies of ecological indicators. [ABSTRACT FROM AUTHOR]