Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – http://www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.

The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

Open-pit coal mining causes strong negative impacts on biodiversity because this activity completely removes thick layers of soil. Focusing on ants as functional agents responding to mine site rehabilitation has proven useful in improving restoration practices. This study sought to evaluate the success of the 20-year-old ecological rehabilitation program at El Cerrejón, one of the world's largest open-pit coal mining operation located in a vulnerable dry tropical forest region of Colombia. This study compared ant assemblages in 13 sites classified along a gradient of rehabilitation sites aged 0-14 years, as well as in three forest reference areas. Two sampling methods (pitfall traps and visual search) were conducted during three sampling periods. Seed removal by ants was also quantified at seven of the 13 sites using seed bait from native plants.Eighty-two ant species, belonging to 29 genera, were found. The highest number of ant species were found inside the forests. Ant species richness increased with rehabilitation age of sites, along with higher canopy cover and milder soil temperature. Rehabilitation actions enhancing these ecological factors might, therefore, favor the presence of wild fauna such as ants. The oldest area (14 years) was the most similar to the forests, both in terms of functional ant groups (guilds) and dominant species. Seed movement was highest in the 14-year-old restored area and was similar to that of the forests, suggesting that this ecological function has been partially restored and that the movement of seed dispersal agents across the landscape would be enhanced.

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Understanding the impact of land use change within assemblages is fundamental to mitigation policies at local and regional scale. Here, we aim to quantify how site-level terrestrial assemblages are responding to land use change in Colombia a mega-diverse country and to project future biodiversity under different scenarios of land use change associated with climate change policies. Location: Colombia (northern South America). Methods: We collated original biodiversity data from 17 publications (285 sites) that examined how human impact affects terrestrial biodiversity in Colombia. From each site we estimated compositional intactness (i.e. compositional similarity to undisturbed sites). We fitted generalized linear mixed-effects models to estimate how these measures of local biodiversity vary across land use habitats. Using space-for-time substitution, we applied our estimates to hindcast biodiversity changes since 1500 and project future changes under climate change policies of the four representative concentration pathways (RCPs). Results: Assemblages in urban, cropland and pasture sites were compositionally very different from those in primary vegetation. We infer that average compositional intactness has been reduced by 18% across Colombia to date, with strong regional variation. The best RCP scenario for future biodiversity is GCAM-RCP4.5, a path that favours the expansion of secondary forests under a strong carbon market; while the worst is MESSAGE-RCP8.5, ‘the business-as-usual’ scenario. Main conclusions: Land use change has driven an increasing change in the composition of ecological assemblages in Colombia. By 2095, the implementation of carbon markets policy of climate change from GCAM-RCP4.5 could mitigate these changes in community composition. In contrast, the business-as-usual scenario MESSAGE-RCP8.5 predicts a steep community change placing the quality of ecosystems at risk

The knowledge of soil indicators during forest restoration is essential for understanding the recovery of ecosystem functions such as biomass production and water regulation. Despite this importance, in most restoration programs over the world, the soil remains under-investigated. Here, we conducted a systematic literature review in order to determine: (1) the extent to which soil indicators are monitored during forest restoration in Colombia; (2) the type of soil indicators (e.g. physical, chemical, or biological) that are used for the monitoring; and (3) the regions where soil indicators are measured. We found 34 studies that report soil indicators. The most frequently studied restoration sites were 0-5 years old (36%). The majority (71%) of the studies only measured the soil characteristics at the topsoil. Soil sodium (Na) and phosphorus (P) concentrations were the most common chemical soil indicators reported by the studies. Soil biological indicators were the least frequently reported indicators. The studies rarely reported soil indicators that affect water movement directly. Of the retrieved studies, most included information about old-growth forests (63%) or degraded sites (56%) for comparisons with forests undergoing restoration. Based on these results we provide recommendations for monitoring soil characteristics to assess the effectiveness of forest restoration projects in Colombia, and other tropical countries.

Secondary tropical forests and coffee agroforestry systems contain fewer trees than native forests but can positively impact soil hydrological functions, such as water infiltration compared to the pasture land that they replace. However, for both land uses it remains in how far the soil hydraulic characteristics are comparable to that of native forest. Therefore, we investigated the saturated hydraulic conductivity (Ks) and some hydrophysical soil attributes in four land-use types: (i) a shade-grown coffee; (ii) a natural regenerated forest 15 years ago; (iii) a pasture; and (iv) a reference forest, in the municipality of La Jagua de Ibirico, César department, Colombia. We determined historical land use and conducted soil sampling, using the Beerkan method to determine the Ks values. We also measured canopy cover, vegetation height, diameter at breast height and total number of trees in the forest covers. Our results indicate that Ks values were similar for the coffee and the reference forest, reflecting the positive effect of trees on soil hydrological functioning in agroforestry systems. Our results suggest that 15 years of forest regeneration after land abandonment in Sub-Andean Forest, can improve the soil hydraulic attributes. Additionally, soil water repellency was observed for the reference forest soil.

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