Aim: Macroinvertebrates comprise a highly diverse set of taxa with great potential as indicators of soil quality. Communities were sampled at 3,694 sites distributed worldwide. We aimed to analyse the patterns of abundance, composition and network characteristics and their relationships to latitude, mean annual temperature and rainfall, land cover, soil texture and agricultural practices.Location: Sites are distributed in 41 countries, ranging from 55° S to 57° N latitude, from 0 to 4,000 m in elevation, with annual rainfall ranging from 500 to >3,000 mm and mean temperatures of 5-32°C.

Assessing how much management of agricultural landscapes, in addition to protected areas, can offset biodiversity erosion in the tropics is a central issue for conservation that still requires cross-taxonomic and landscape-scale studies. We measured the effects of Amazonia deforestation and subsequent land-use intensification in 6 agricultural areas (landscape scale), where we sampled plants and 4 animal groups (birds, earthworms, fruit flies, and moths). We assessed land-use intensification with a synthetic index based on landscape metrics (total area and relative percentages of land uses, edge density, mean patch density and diversity, and fractal structures at 5 dates from 1990 to 2007). Species richness decreased consistently as agricultural intensification increased despite slight differences in the responses of sampled groups. Globally, in moderately deforested landscapes species richness was relatively stable, and there was a clear threshold in biodiversity loss midway along the intensification gradient, mainly linked to a drop in forest cover and quality. Our results suggest anthropogenic landscapes with high-quality forest covering >40 % of the surface area may prevent biodiversity loss in Amazonia.

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The relationship between changes in land use and soil carbon and nitrogen was assessed in Alcalá (colombian coffee growing region), between 900 and 1600 m. Soils are Argiudolls and Melanudands and sampling units were defined according to the altitudinal gradient. Carbon and nitrogen content, C:N ratio, bulk density and 13C and 15 N abundances were measured. Significant differences (p < 0.05) were found due to altitude effect, differentiating the high zone by high C (37.06 -42.88 t ha -1 ), N (3.12-3.86 t ha -1 ) and C: N (11.17-11.97), low bulk density (0.56-0.65 g cm -3 ) and 15 N abundance (4.59-5.15 ‰). Fallow and monocultures stored more carbon in deeper layers of the soil, while most preserved sites showed low C, N contents. The 13 C in land uses ranged between -25.18‰ and -21.17 ‰, indicating that carbon was fixed mainly by C 3 plants. It was concluded that land use changes affect C stocks, due to practices like chemical fertilization; and Alcalá soils have high potential for ecosystem services related with edaphic carbon capture.Keywords: carbon sequestration in the Andes, land use changes, stable isotopes RESUMEN Se estudió la relación de cambios en el uso del terreno con el C y N edáficos, en el municipio de Alcalá (región cafetera colombiana), entre 900 y 1600 m de elevación. Los suelos son Argiudolls y Melanudands y las unidades de muestreo fueron definidas según el gradiente altitudinal. Se midieron contenidos de C y N, relación C:N, densidad aparente y abundancias de 13 C y 15 N. Se encontraron diferencias significativas (p < 0,05) por el efecto de la altura. La zona alta mostró mayores contenidos de C (37,06-42,88 t ha -1 ) y N (3,12 -3,86 t ha -1 ), mayor relación C: N (11,17 -11,97), menor densidad aparente (0.56 -0.65 g cm -3 ) y abundancia de 15N (4,59 -5,15‰). Barbechos y monocultivos almacenaron más carbono en la parte subterránea del suelo; mientras que en sitios más conservados los contenidos de C y N fueron bajos. El 13 C según los usos, fluctuó entre -25,18 y -21,27‰ indicando que la mayoría del C fue fijado por plantas C 3 . Se concluyó que los cambios en el uso afectan el almacenamiento de C, 222

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