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{"Abstract":["The data in this package is associated with the analysis for a manuscript titled\n "Multiple community properties drive ecosystem resistance and resilience to extreme climate\n events across mesic grasslands". The files include compiled data on plant biomass production,\n species abundance, experimental treatments, extreme climate event values, and calculated\n diversity and stability measures from grassland plots in experiments at CDR, KBS, and KNZ LTER\n sites."]} 

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. 

Experiments comparing diploids with polyploids and in single grassland sites show that nitrogen and/or phosphorus availability influences plant growth and community composition dependent on genome size; specifically, plants with larger genomes grow faster under nutrient enrichments relative to those with smaller genomes. However, it is unknown if these effects are specific to particular site localities with speciifc plant assemblages, climates, and historical contingencies. To determine the generality of genome size-dependent growth responses to nitrogen and phosphorus fertilization, we combined genome size and species abundance data from 27 coordinated grassland nutrient addition experiments in the Nutrient Network that occur in the Northern Hemisphere across a range of climates and grassland communities. We found that after nitrogen treatment, species with larger genomes generally increased more in cover compared to those with smaller genomes, potentially due to a release from nutrient limitation. Responses were strongest for C₃grasses and in less seasonal, low precipitation environments, indicating that genome size effects on water-use-efficiency modulates genome size–nutrient interactions. Cumulatively, the data suggest that genome size is informative and improves predictions of species’ success in grassland communities. 

Abstract Context Habitat fragmentation is a leading threat to biodiversity, yet the impacts of fragmentation on most taxa, let alone interactions among those taxa, remain largely unknown. Objectives We studied how three consequences of fragmentation—reduced patch connectivity, altered patch shape, and edge proximity—impact plant-dwelling mite communities and mite-plant-fungus interactions within a large-scale habitat fragmentation experiment. Methods We sampled mite communities from the leaves of Quercus nigra (a plant species that has foliar domatia which harbor fungivorous and predacious mites) near and far from edge within fragments of varying edge-to-area ratio (shape) and connectivity via corridors. We also performed a mite-exclusion experiment across these fragmentation treatments to test the effects of mite presence and fungal hyphal abundance on leaf surfaces. Results Habitat edges influenced the abundance and richness of leaf-dwelling mites; plants closer to the edge had higher mite abundance and species richness. Likewise, hyphal counts were higher on leaves near patch edges. Despite both mite and fungal abundance being higher at patch edges, leaf hyphal counts were not impacted by mite abundance on those leaves. Neither patch shape nor connectivity influenced mite abundance, mite species richness, or the influence of mites on leaf surface fungal abundance. Conclusion Our results suggest that mites and foliar fungi may be independently affected by edge-structured environmental gradients, like temperature, rather than trophic effects. We demonstrate that large-scale habitat fragmentation and particularly edge effects can have impacts on multiple levels of microscopic communities, even in the absence of cascading trophic effects.