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Species from OCBILs (old, climatically buffered, infertile landscapes) are expected to exhibit reduced dispersability, linked to long-term stable environmental conditions. We tested the prediction of limited dispersability in plant communities in campo rupestre, a megadiverse OCBIL grassland. In a field experiment, we sampled sticky and funnel traps for 12 months along paired preserved and disturbed plots to estimate and compare annual seed density and richness. Our community-level seed rain assessment suggested widespread seed limitation in both preserved and disturbed areas, expressed by the low seed density in traps (average of 2.6 seeds/m2/day) and remarkably low seed density found for 90% of the morphospecies. Although seed density in campo rupestre was much lower than for other grasslands, species richness (92 seed morphospecies) was the highest reported in the literature. Higher seed density and species richness were captured in funnel traps, especially during the rainy season. Approximately 32% of morphospecies were registered exclusively in disturbed plots and 25% exclusively in preserved plots. This limited seed dispersability is of particular relevance for a better understanding of seed ecology and resilience in campo rupestre and may partially explain the poor recovery of these disturbed areas after soil removal.

Global sustainability rests on a myriad of benefits provided by natural ecosystems that support human livelihoods and well-being, from biodiversity persistence to climate regulation. The undeniable importance of conserving tropical forests has drawn most of the conservation spotlight towards it. However, open ecosystems such as the Brazilian Campo Rupestre (rupestrian grassland), have been historically overlooked despite their high diversity and key associated ecosystem services. We highlight major current threats to the persistence of the Campo Rupestre emphasizing its ecological, social, cultural, geo-environmental, and economic importance. We call attention to the importance of the Campo Rupestre as a reservoir of biodiversity and ecosystem services and offer priority actions that resulted from discussions involving scientists, industry representatives, environmental managers, and other members of civil society. Proposed actions include efforts related to ecological restoration, sustainable ecotourism, protection of traditional ecological knowledge, identification of emerging research questions, and development of tailored public policies. Such issues are integrated into a framework that collectively represents a road map to safeguard the Campo Rupestre from further degradation and steer its historical overexploitation towards sustainable management. Safeguarding the future of non-forest biomes like this poses a challenge to current paradigms of nature conservation. By establishing priorities and guidelines, we propose an actionable plan, which we hope can support informed decision-making policy towards a sustainable use of the Campo Rupestre. Long Term Ecological Research PELD-CRSC-17 Conselho Nacional de Pesquisas CNPq/MCTI Fundação de Amparo à Pesquisa do Estado de São Paulo 2013/50155-0, 2010/51307-0, 2019/07773-1

Larger flowers greatly increase among-individual pollen exchange within populations. However, water costs associated to transpirational cooling also increase with increasing flower size. Overall, the interplay between pollen and resource limitation determines the intensity of selection on flower size and this process is mostly dependent on gender and ecological context. To examine how pollinators and water use affect flower size, we determined corolla transpiration, pollen limitation, and selection through male and female fitness in two Kielmeyera species from the Brazilian cerrado flowering at different seasons. Hand-pollination experiments suggested pollen limitation through female fitness in both species, but K. coriacea showed lower limitation levels than K. regalis. For male fitness, the percentage of pollen removal was 1.5-times higher in K. coriacea. Higher air temperature and water deficit during flowering season of K. coriacea resulted in 4-fold higher corolla transpiration rates compared to K. regalis. Selection on flower size through male function was positive and significantly higher than selection through female components in both species. We also detected stabilizing selection in K. coriacea and positive selection in K. regalis on flower size through seed number. Our results suggest that selection on flower size in K. coriacea was mainly limited by water, whereas in K. regalis it was more limited by pollen. We demonstrate that differences in pollen and abiotic resource limitation determine gender-specific selection on flower size.

International audience; Questions: Anthropogenic disturbances are known to be followed by extremely poor recovery in edaphic grasslands. However, the role of interactions with diaspore predators and secondary dispersers, which compose the dispersal filter and modulate plant community recovery, has been overlooked. We performed field experiments to investigate how soil disturbances affect diaspore interactions with the ground‐foraging fauna to better understand how disturbance influences regeneration potential.Location: Campo rupestre vegetation, megadiverse edaphic grasslands, southeastern Brazil.Methods: We used diaspores from five native species to compare removal rates between disturbed (top soil removal) and preserved sites; we also controlled invertebrate and vertebrate access to determine their role. In addition, we assessed differences in the diaspore removal effectiveness (DRE) and the structure of animal–diaspore interactions through network based‐approach.Results: For three species, the average diaspore removal rates was relatively high (between 30% and 70%). Invertebrates were the most common removal agents in both disturbed and preserved sites. Interactions with foraging fauna and removal rates were 20% smaller in disturbed sites. Considering all diaspore removal events in disturbed sites, 24% resulted in the displacement from disturbed to preserved sites, but no diaspore was transported from preserved to disturbed ones. The animal–diaspore network was exclusively composed by ant–diaspore interactions and was more diverse and robust in preserved sites compared with disturbed ones. Seed predator ants (Pheidole and Dorymyrmex) were more common in disturbed sites. Furthermore, significant differences were found in the DRE between ant species and site types, suggesting specificity in the provision of dispersal services.Conclusions: Topsoil removal affected removal proportions, DRE and ant–diaspore interaction network structure. The lack of diaspore dispersal towards disturbed sites indicates that soil removal affects secondary seed removal dynamics, impeding recovery potential. Disturbance negatively affected diaspore fate by reshaping interactions with ground‐foraging secondary seed dispersers and predators, constraining the development of seed bank and thus impacting upon vegetation dynamics and resilience.