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Question Are trait‐convergence assembly patterns (TCAP) and/or trait‐divergence assembly patterns (TDAP) of tree sapling communities related to microhabitat gradients in forest patches? If so, which traits are related to such patterns? What are the niche mechanisms potentially responsible for community assembly? Location Grassland–forest mosaic in Serra do Sudeste region, southern Brazil (ca. 30.8°S, 53.1°W). Methods We used individual‐based trait information of 1132 tree saplings in 40 plots along gradients of canopy openness and grazing intensity in forest patches in southern Brazil. We used a trait‐based approach, bypassing taxonomic identification, as a first assessment of sapling community assembly in forest patches. Results Both TCAP and TDAP indicate niche mechanisms underlying assembly of tree sapling communities. Specific leaf area (SLA), mean leaf area (LA) and relative abundance of toothed leaf margin (TLM) maximized TCAP. SLA and TLM tended to increase under more closed canopies, whereas LA had higher values at intermediate canopy openness. SLA and LA maximized TDAP and tended to vary more in more closed canopies, whereas SLA and presence of spines, which also maximized TDAP, showed higher variation under lower grazing intensity. Conclusion The taxon‐free approach was very useful to infer niche mechanisms of tree sapling assembly in forest patches. By adopting an individual‐based trait approach, we assumed that both intra‐specific and intra‐population trait variability were relevant for revealing assembly patterns. We highlight that the use of individual‐based trait data in a metacommunity framework is an excellent way to evaluate TCAP and TDAP at the metacommunity scale, since it takes into account the entire variation of traits throughout communities.

Question:Grazing is an important disturbance for maintenance of structure and functioning of the plant communities in grassy ecosystems. Functional characteristics of plants, which are responsible for their response to grazing, vary at inter-and intraspecific levels. Here, we assessed: (1) the extent of intraspecific trait variation when compared to interspecific variability; and (2) how grazing regime affects intraspecific trait variation in leaf functional traits of species with different leaf economics strategies.Location: A multisite grazing experiment in subtropical grasslands, southern Brazil.Methods: For 30 dominant grassland plant species we measured functional traits related to resource acquisition strategy and grazing response (SLA, specific leaf area; LDMC, leaf dry matter content; LA, leaf area; and FT, leaf resistance to traction) under three grazing treatments (grazing exclusion, traditional, or deferred grazing) arranged in a randomized block design. We quantified the overall proportion of intra-and interspecific variation and, for each species, we tested for the grazing treatment effects on intraspecific trait variation through Bayesian analysis of variance. Results:The overall contribution of intraspecific variation was up to 37% of the total variation. For most grass species, grazing exclusion led to lower values of SLA and higher values of LA, while no effect of grazing treatments was detected on intraspecific variation of LDMC and FT. Altogether, the effect of grazing management on intraspecific trait variation was more prevalent in species presenting a conservative strategy than in species with an acquisitive strategy. Conclusion:The expression of leaf traits is variable within species, especially for those species with a conservative strategy of resource acquisition. The extent of intraspecific trait variation in response to grazing depends on the considered traits and the resource acquisition strategy of the studied species.

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