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Questions We investigated the effects of grassland management intensity and temporary conversion to other land uses on abiotic and biotic properties of subtropical grasslands. We used species-rich permanent grasslands of medium management intensity ( PG-M) as a reference, and asked the following questions: (1) do permanent grasslands with low and high management intensities ( PG-L and PG-H, respectively) have different plant diversity and species composition than reference grasslands; and (2) do secondary grasslands recovering from conversion to arable fields ( SG-A) or pine plantations ( SG-P) differ from permanent grasslands in their plant species composition and abiotic conditions? Location Highland grasslands, Campos de Cima da Serra, Rio Grande do Sul ( RS), Brazil. Methods We analysed variation in plant species composition and diversity among 80 grassland sites, including three types of permanent grassland and two types of secondary grassland. An indicator species analysis was used to identify characteristic species for the different land-use types. We used a linear discriminant analysis to investigate differences in soil conditions among land-use types. Results Both PG-L and PG-H differed from PG-M regarding plant species composition. Although PG-L shared many typical grassland species with PG-M, their communities were generally less diverse. PG-H, on the other hand, not only had fewer species but also deviated from PG-M in species composition. Secondary grasslands on former arable fields and plantations differed from PG-M in species composition and showed lower diversity. Soil conditions of SG-P were similar to those of PG-L and PG-M, but they were distinct from those of PG-H and SG-A. Conclusions All land-use types showed deviations from reference grasslands ( PG-M). The decrease in the number of species in PG-L may be reversed if traditional management intensity is re-introduced, whereas strong compositional changes in SG-P may require the re-introduction of grassland species. This is also true for PG-H and SG-A: both showed marked deviations from reference grasslands in biotic and abiotic components. Overall, restoration of altered land-use types to near-natural subtropical grassland seems feasible, but suitable techniques have to be developed. [ABSTRACT FROM AUTHOR]

In the past decades, Brazil made important progress in the conservation of forest ecosystems. Non-forest ecosystems ( NFE), in contrast, have been neglected, even though they cover large parts of the country and have biodiversity levels comparable to forests. To avoid losing much of its biodiversity and ecosystem services, conservation and sustainable land use policies in Brazil need to be extended to NFE. A strategy for conservation of Brazil's NFE should encompass the following elements: (1) creation of new large protected areas in NFE; (2) enforcement of legal restrictions of land use; (3) extension of subsidy programs and governance commitments to NFE; (4) improvement of ecosystem management and sustainable use in NFE; and (5) improvement of monitoring of land use change in NFE. If Brazil managed to extend its conservation successes to NFE, it not only would contribute significantly to conservation of its biodiversity, but also could take the lead in conservation of NFE world-wide. [ABSTRACT FROM AUTHOR]

Understanding how land use and management practices affect biodiversity is essential for developing effective restoration and conservation strategies. Here, we used ant communities to evaluate the effects of historical land uses (former agriculture or tree plantation) and current management (grazing, burning, mowing, and fertilizing) in subtropical grasslands. We also examined how ant species richness and composition are affected through changes in resource diversity and habitat structure. We classified 80 study sites in southern Brazil into two groups: permanent and secondary grasslands. Permanent grasslands presented high, medium or low management intensities that had never been under other land use. Secondary grasslands are former grasslands that were used for agriculture or pine plantations in the past, followed by passive restoration. We sampled ant communities with D-Vac suction in three multiplots per site in 2013–2015. We found that secondary grasslands had lower ant species diversity and different community composition than permanent grasslands. Ant diversity did not differ among permanent grasslands, but composition was markedly different, especially when comparing medium and high management intensities with low. Additionally, ant richness in secondary grasslands was mainly mediated by a decreased resource diversity (i.e., plant species richness) and grass cover, while burning and mowing management increased ant richness by increasing resource diversity. Our results indicate that passive recovery of grasslands in early successional stages after other land uses leads to incomplete recovery of ant communities, as important resource and structure-related drivers of ant species remain altered. In contrast, traditional management practices promote ant diversity. • Historical and current land use shape ant communities in subtropical grasslands. • Secondary grasslands have reduced ant diversity and altered species composition. • Management intensity did not affect ant richness but drive species composition. • Resource diversity and grass cover loss are the main drivers of ant community changes. • Ants can be used as indicators in conservation and restoration monitoring in subtropical grasslands. [ABSTRACT FROM AUTHOR]