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South American grasslands, socio-ecological systems used heavily for a long time, are currently experiencing dramatic land-use changes due to implementation of large-scale afforestation and agro-industrial cash crops. Applying the conceptual framework of “Multifunctional and sustainable productive landscapes” to Uruguay, we explored the impacts on rural ecosystems and communities based on a long-term monitoring network by assessing species richness of plant and terrestrial arthropods and socio-economic data from national census. We found that silvi- and agricultural industry established mainly at the expense of extensively grazed grasslands and local family farms with traditional techniques, accompanied by a deregulation of the rural labor market, depopulation and aging of rural society. Governmental nature protection efforts increase the native forest cover and establish nature protection areas focusing mainly on forests. We also discuss pathways of land-use change in recent decades and related discourses of local stakeholders.

We explore the effect of land‐use change from extensively used grasslands to intensified silvi‐ and agricultural monocultures on metacommunity structure of native forests in Uruguay. We integrated methods from metacommunity studies, remote sensing, and landscape ecology to explore how woody species distribution was influenced by land‐use change from local to regional scale. We recorded richness and composition of adult and juvenile woody species from 32 native forests, created land‐use maps from satellite image to calculate spatial metrics at landscape, class, and patch levels. We also analyzed the influence of land use pattern, climate, topography, and geographic distance between sites (d) on metacommunity, and created maps to visualize species richness and (dis)similarity between communities across the country. Woody species communities were distributed in a discrete pattern across Uruguay. Precipitation and temperature seasonality shaped species distribution pattern. Species richness and community dissimilarity increased from West to East. Latitude did not influence these patterns. Number of patches, landscape complexity, and interspersion and juxtaposition indexes determine woody species distribution at landscape level. Increasing areas covered by crops and timber plantation reduced species richness and increased community dissimilarity. The spatial metrics of native forest fragments at patch level did not influence metacommunity structure, species richness, and community dissimilarity. In conclusion, Uruguayan native forests display a high range of dissimilarity. Pressure of neighborhood land uses was the predominant factor for species assemblages. Conserving landscape structures that assure connectivity within and among native forest patches is crucial. On sites with rare target species, the creation of alliances between governmental institution and landowner complemented by incentives for biodiversity conservation provides opportunities to advance in species protection focused on those less tolerant to land‐use change.

Abstract. The ‘soils of the anthropocene’ are predominately agricultural. To understand them, we analysed agri- and silvicultural intensification of Uruguayan grasslands in a country wide survey on fertility proxies, pH and trace metals in topsoils originating from different land uses. We observed a loss of nutrients, trace metals and organic matter from grassland, crops and timber plantations, and its accumulation in the topsoils of riverine forests. The translocation of nutrients and organic matter across the landscape to the erosion base depends on local land use trajectories. Increasing soil acidification is driving a positive feedback loop, and land use intensification is leading to degradation of local black soils within a few decades. Our data raises questions about the resilience and carrying capacity of Uruguayan soils with regard to currently implemented highly productive management forms, including the use of timber plantation for carbon sequestration, and supports more conservative forms of extensive management on the grassland biome.

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