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Abstract Habitat loss is a major threat to biodiversity, but the effects of habitat fragmentation are less clear. Examining drivers of key demographic processes, such as reproduction, will clarify species‐level responses to fragmentation and broader effects on biodiversity. Yet, understanding how fragmentation affects demography has been challenging due to the many ways landscapes are altered by co‐occurring habitat loss and fragmentation, coupled with the rarity of experiments to disentangle these effects.In a large, replicated fragmentation experiment with open savanna habitats surrounded by pine plantation forests, we tested the effects of inter‐patch connectivity, patch edge‐to‐area ratio, and within‐patch distance from an edge on plant reproductive output. Using five experimentally planted species of restoration interest—three wind‐pollinated grass species and two insect‐pollinated forb species—we measured plant flowering, pollination rate, and seed production.All plant species were more likely to flower and produce more flowering structures farther from the forest edge. Connectivity and distance from an edge, however, had no effect on the pollination rate (regardless of pollination mode). Despite no influence of fragmentation on pollination, plant seed production increased farther from the edge for four of five species, driven by the increase in flower production.Synthesis. Altogether, we demonstrate that plant reproductive output (seed production) is decreased by habitat fragmentation through edge effects on flowering. Our work provides evidence that an important contributor to plant demography, reproductive output, is altered by edge effects in fragmented patches. These species‐level impacts of fragmentation may provide insight into the mechanisms of fragmentation effects on community‐level changes in biodiversity. 

Abstract Ecological restoration is beneficial to ecological communities in this era of large‐scale landscape change and ecological disruption. However, restoration outcomes are notoriously variable, which makes fine‐scale decision‐making challenging. This is true for restoration efforts that follow large fires, which are increasingly common as the climate changes.Post‐fire restoration efforts, like tree planting and seeding have shown mixed success, though the causes of the variation in restoration outcomes remain unclear. Abiotic factors such as elevation and fire severity, as well as biotic factors, such as residual canopy cover and abundance of competitive understorey grasses, can vary across a burned area and may all influence the success of restoration efforts to re‐establish trees following forest fires.We examined the effect of these factors on the early seedling establishment of a tree species—māmane (Sophora chrysophylla)—in a subtropical montane woodland in Hawaiʻi. Following a human‐caused wildfire, we sowed seeds of māmane as part of a restoration effort. We co‐designed a project to examine māmane seedling establishment.We found that elevation was of overriding importance, structuring total levels of plant establishment, with fewer seedlings establishing at higher elevations. Residual canopy cover was positively correlated with seedling establishment, while cover by invasive, competitive understorey grasses very weakly positively correlated with increased seedling establishment.Our results point to specific factors structuring plant establishment following a large fire and suggest additional targeted restoration actions within this subtropical system. For example, if greater native woody recruitment is a management goal, then actions could include targeted seed placement at lower elevations where establishment is more likely, increased seeding densities at high elevation where recruitment rates are lower, and/or invasive grass removal prior to seeding. Such actions may result in faster native ecosystem recovery, which is a goal of local land managers. 

Abstract Spatial rarity is often used to predict extinction risk, but rarity can also occur temporally. Perhaps more relevant in the context of global change is whether a species is core to a community (persistent) or transient (intermittently present), with transient species often susceptible to human activities that reduce niche space. Using 5–12 yr of data on 1,447 plant species from 49 grasslands on five continents, we show that local abundance and species persistence under ambient conditions are both effective predictors of local extinction risk following experimental exclusion of grazers or addition of nutrients; persistence was a more powerful predictor than local abundance. While perturbations increased the risk of exclusion for low persistence and abundance species, transient but abundant species were also highly likely to be excluded from a perturbed plot relative to ambient conditions. Moreover, low persistence and low abundance species that were not excluded from perturbed plots tended to have a modest increase in abundance following perturbance. Last, even core species with high abundances had large decreases in persistence and increased losses in perturbed plots, threatening the long‐term stability of these grasslands. Our results demonstrate that expanding the concept of rarity to include temporal dynamics, in addition to local abundance, more effectively predicts extinction risk in response to environmental change than either rarity axis predicts alone.