Moderation and mediation of land use change! Interplay between β‐diversity and landscape structures in agri‐ and silvicultural modified grasslands of South America

Abstract

Although land use change is the main driver of biodiversity decline in the South American temperate grasslands, its impacts on β‐diversity have not yet been evaluated. We investigated relationships between β‐diversity, landscape features, and geographical variables by surveying vegetation from 163 plots distributed in eight different land use types in Uruguay. We created land use maps using Landsat images and calculated landscape metrics, determining β‐diversity across all plots and exploring variation of β‐diversity among different land use types. We ran distance decay models to explore relationships between β‐diversity and geographical location, climate, and landscape metrics. Plant species communities were characterized by a high turnover and low nestedness of species, indicating high dissimilarity across Uruguay. Native forest showed higher β‐diversity than grassland, timber plantation, and crops. β‐diversity increased with geographical distance and environmental dissimilarity. At landscape scale, turnover decreased negatively and nestedness increased to contagion, number of patches, and area‐weighted mean. Nestedness increased with timber plantation and species turnover with crop area. Higher Landscape Shape Index of grassland and crops decreased species turnover. An increase of grassland and crop patches in the surrounding landscape was directly related to a higher species turnover. The high β‐diversity across Uruguay resulting from land use change, moderated by landscape configurations, suggests that numerous protected areas for different habitats are urgently required. A more inclusive vision on biodiversity conservation is necessary, extending the predominant focus from native forests to grasslands, and convincing a broad range of stakeholders, especially landowners and managers, about biodiversity‐friendly land‐use approaches.