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Within ecosystems, intra‐annual precipitation patterns—the variability and timing of rainfall—may be a stronger driver of net primary productivity than total annual precipitation. In particular, the amount and timing of precipitation directly affects the amount and timing of plant production, but also indirectly affects productivity via changes to plant community composition. Community response patterns may either buffer or amplify productivity responses to precipitation, as different species respond to different conditions.In a semi‐arid California grassland, we experimentally tested how plant communities respond to intra‐annual precipitation using rainout shelters in which we manipulated drought amount and timing (early season drought, late season drought, continuous drought and ambient precipitation) over 3 years and assessed plant responses: annual net primary productivity (ANPP), phenological timing of peak production and senescence, and community composition.Overall, early season and consistent drought treatments had lowest productivity, while late season and consistent drought treatments senesced earlier. Plots with functionally diverse communities shifted community composition and had a significant ANPP response to precipitation treatments. In contrast, communities dominated by a single resource‐acquisitive grass species did not change in community composition over time and had no ANPP response to precipitation treatments.The timing of production also differed by community, however, where functionally diverse communities remained green longer (particularly under the early season drought treatment) compared to communities dominated by one grass species, which senesced earlier (particularly under the late season drought treatment).Synthesis. Our study demonstrates that drought patterns may indirectly drive ANPP via plant community responses in composition and phenology. This suggests that the combination of species composition and vegetation phenology could jointly alter ecosystem‐level sensitivity to precipitation seasonality under future climate change. We show that both functional diversity and dominant stability mechanisms are in operation simultaneously, highlighting the need to understand both the context and variation in community structure to predict ANPP responses to intra‐annual precipitation. [ABSTRACT FROM AUTHOR]

Fluctuations in population abundances are often correlated through time across multiple locations, a phenomenon known as spatial synchrony. Spatial synchrony can exhibit complex spatial structures, termed 'geographies of synchrony', that can reveal mechanisms underlying population fluctuations. However, most studies have focused on spatial extents of 10s to 100s of kilometres, making it unclear how synchrony concepts and approaches should apply to dynamics at finer spatial scales.We used network analyses, multiple regression on similarity matrices, and wavelet coherence analyses to examine micro‐scale synchrony and geographies of synchrony, over distances up to 30 m, in a serpentine grassland plant community.We found that species' populations exhibited a geography of synchrony even over such short distances. Often, well‐synchronized populations were geographically separate, a spatial structure that was shaped mainly by gopher disturbance and dispersal limitation, and to a lesser extent by relationships with other plant species. Precipitation was a significant driver of site‐ and community‐wide temporal dynamics. Gopher disturbance appeared to drive synchrony on 2‐ to 6‐year timescales, and we detected coherent fluctuations among pairs of focal plant taxa.Synthesis. Micro‐geographies of synchrony are an intriguing phenomenon that may also help us better understand community dynamics. Additionally, the related geographies of synchrony and coherent temporal dynamics among some species pairs indicate that incorporating interspecific interactions can improve understanding of population spatial synchrony. [ABSTRACT FROM AUTHOR]

Question: Inter‐annual species mobility within a community might support species co‐existence in species‐rich ecosystems. We asked how species mobility within a highly diverse grassland community is affected by species traits and how external conditions (management) affect mobility. Location: Semi‐natural wet meadow in southern Bohemia, Czech Republic (48°57′ N, 14°36′ E, 510 m a.s.l.). Methods: A manipulative experiment comprising mowing, fertilization, and removal of the dominant species Molinia caerulea was established, in factorial design, in a semi‐natural species‐rich meadow in 1994. Rooting presence of all species was recorded in individual 0.1 m × 0.1 m cells grid within 0.5 m × 0.5 m permanently fixed quadrats. We used a 14‐year continuous time series to evaluate species persistence (ability to stay in a cell over time) in each plot, using the point correlation coefficient (V), and related persistence to different plant traits. At the community level we also determined mobility, as floristic dissimilarity of the individual cell and the whole 0.5 m × 0.5 m quadrat across contiguous years. Results: The differences in traits and mobility among species were remarkable: "sitters," retaining their spatial position (e.g. Succisa pratensis, Carex umbrosa) had tougher leaves, usually had shoot generation overlap, a rosette and did not have effective clonal spreading; "travelers" (e.g. Lysimachia vulgaris, Lathyrus pratensis) changed their position frequently and had opposite traits. Of the experimental factors, only mowing affected mobility, increasing persistence, but all factors modified species mobility ranking slightly. Against expectation, species richness was negatively correlated with community mobility. Conclusions: A high degree of mobility in species‐rich meadows does not necessarily enhance diversity. However, a functional differentiation between more mobile and fixed species can be expected within co‐existing species. Species mobility is highly species‐specific and less affected by management. [ABSTRACT FROM AUTHOR]

Aims: Post‐fire succession in low‐productivity ecosystems is rarely directly measured. We test whether taxonomic, functional, or baseline convergence has occurred 128 years after a major fire in 1890 in a low‐productivity, fire‐susceptible subalpine ecosystem. The historical plots represent one of the longest‐running quantitative ecological studies in the world. Location: Arthur's Pass, South Island, New Zealand. Methods: We remeasured historical plots at sites established 42 years after the fire, and modernised previous chart quadrat data to percentage frequency. We tested whether taxonomic and functional dissimilarity within the site, and within environmentally similar transect groups, reduced over time. We used pollen data preserved in soil cores taken on the plots to test whether the site had returned to the reference pre‐fire baseline. Results: There is little evidence of taxonomic convergence across the site and dissimilarity remains high. Functional dissimilarity showed little reduction or evidence of convergence. Within maximally similar groups of transects, taxonomic and functional dissimilarity declined over time. Tree frequency increased significantly year‐on‐year. There is a lack of convergence with the pre‐fire baseline, accompanied by a reduction in the proportion of tree pollen represented on most transects. Conclusions: The taxonomic rate of successional change has yet to slow, and a steady state has yet to be reached, suggesting it is too early to consider the site has attained maximal convergence. Palaeoecological data have allowed quantification of the effect of a novel fire regime to which the ecosystems are poorly adapted: we found compositional, structural, and dominant‐species differences between pre‐ and post‐fire vegetation. Combining permanent transects and palaeoecological data allows for a synthesis of data at multiple time scales, permitting investigations of long‐duration successions. [ABSTRACT FROM AUTHOR]

Restoration ecology is a deepening and diversifying field with current research incorporating multiple disciplines and infusing long-standing ideas with fresh perspectives. We present a list of 10 recent pivotal papers exemplifying new directions in ecological restoration that were selected by students in a cross-disciplinary graduate seminar at the University of California, Berkeley. We highlight research that applies ecological theory to improve restoration practice in the context of global change (e.g. climate modeling, evaluation of novel ecosystems) and discuss remaining knowledge gaps. We also discuss papers that recognize the social context of restoration and the coupled nature of social and ecological systems, ranging from the incorporation of cultural values and Traditional Ecological Knowledge into restoration, to the consideration of the broader impacts of markets on restoration practices. In addition, we include perspectives that focus on improving communication between social and natural scientists as well as between scientists and practitioners, developing effective ecological monitoring, and applying more integrated, whole-landscape approaches to restoration. We conclude with insights on recurrent themes in the papers regarding planning restoration in human-modified landscapes, application of ecological theory, improvements to restoration practice, and the social contexts of restoration. We share lessons from our cross-disciplinary endeavor, and invite further discussion on the future directions of restoration ecology through contributions to our seminar blog site . [ABSTRACT FROM AUTHOR]

Many terrestrial plant communities, especially forests, have been shown to lag in response to rapid climate change. Grassland communities may respond more quickly to novel climates, as they consist mostly of short-lived species, which are directly exposed to macroclimate change. Here we report the rapid response of grassland communities to climate change in the California Floristic Province. We estimated 349 vascular plant species' climatic niches from 829,337 occurrence records, compiled 15 long-term community composition datasets from 12 observational studies and 3 global change experiments, and analysed community compositional shifts in the climate niche space. We show that communities experienced significant shifts towards species associated with warmer and drier locations at rates of 0.0216 ± 0.00592 °C yr - 1 (mean ± s.e.) and -3.04 ± 0.742 mm yr - 1 , and these changes occurred at a pace similar to that of climate warming and drying. These directional shifts were consistent across observations and experiments. Our findings contrast with the lagged responses observed in communities dominated by long-lived plants and suggest greater biodiversity changes than expected in the near future., (© 2024. The Author(s).)