More Like this

1. Wintering bird communities are tracking climate change faster than breeding communities

   https://doi.org/10.1111/1365-2656.13433  

   Lehikoinen, Aleksi ; Lindström, Åke ; Santangeli, Andrea ; Sirkiä, Päivi M. ; Brotons, Lluís ; Devictor, Vincent ; Elts, Jaanus ; Foppen, Ruud P. B. ; Heldbjerg, Henning ; Herrando, Sergi ; et al ( February 2021 , Journal of Animal Ecology)

   Global climate change is driving species' distributions towards the poles and mountain tops during both non‐breeding and breeding seasons, leading to changes in the composition of natural communities. However, the degree of season differences in climate‐driven community shifts has not been thoroughly investigated at large spatial scales.

   We compared the rates of change in the community composition during both winter (non‐breeding season) and summer (breeding) and their relation to temperature changes.

   Based on continental‐scale data from Europe and North America, we examined changes in bird community composition using the community temperature index (CTI) approach and compared the changes with observed regional temperature changes during 1980–2016.

   CTI increased faster in winter than in summer. This seasonal discrepancy is probably because individuals are less site‐faithful in winter, and can more readily shift their wintering sites in response to weather in comparison to the breeding season. Regional long‐term changes in community composition were positively associated with regional temperature changes during both seasons, but the pattern was only significant during summer due to high annual variability in winter communities. Annual changes in community composition were positively associated with the annual temperature changes during both seasons.

   Our results were broadly consistent across continents, suggesting some climate‐driven restructuring inmore »both European and North American avian communities. Because community composition has changed much faster during the winter than during the breeding season, it is important to increase our knowledge about climate‐driven impacts during the less‐studied non‐breeding season.

   « less
2. Persistent decadal differences in plant communities assembled under contrasting climate conditions

   https://doi.org/10.1002/eap.2823  

   Eckhoff, Kathryn D. ; Scott, Drew A. ; Manning, George ; Baer, Sara G. ( March 2023 , Ecological Applications)

   Plant community assembly outcomes can be contingent upon establishment year (year effects) due to variations in the environment. Stochastic events such as interannual variability in climate, particularly in the first year of community assembly, contribute to unpredictable community outcomes over the short term, but less is known about whether year effects produce transient or persistent states on a decadal timescale. To test for short‐term (5‐year) and persistent (decadal) effects of establishment year climate on community assembly outcomes, we restored prairie in an agricultural field using the same methods in four different years (2010, 2012, 2014, and 2016) that captured a wide range of initial (planting) year climate conditions. Species composition was measured for 5 years in all four restored prairies and for 9 and 11 years in the two oldest restored prairies established under average precipitation and extreme drought conditions. The composition of the four assembled communities showed large and significant differences in the first year of restoration, followed by dynamic change over time along a similar trajectory due to a temporary flush of annual volunteer species. Sown perennial species eventually came to dominate all communities, but communities remained distinct from each other in year five. Precipitation in June and Julymore »of the establishment year explained short‐term coarse community metrics (i.e., species richness and grass/forb cover), with wet establishment years resulting in a higher cover of grasses and dry establishment years resulting in a higher cover of forbs in restored communities. Short‐term differences in community composition, species richness, and grass/forb cover in restorations established under average precipitation and drought conditions persisted for 9–11 years, with low interannual variability in the composition of each prairie over the long term, indicating persistently different states on a decadal timescale. Thus, year effects resulting from stochastic variation in climate can have decadal effects on community assembly outcomes.

   « less
3. Biotic and abiotic drivers of plant–pollinator community assembly across wildfire gradients

   https://doi.org/10.1111/1365-2745.13530  

   LaManna, Joseph A. ; Burkle, Laura A. ; Belote, R. Travis ; Myers, Jonathan A. ; Bartomeus, ed., Ignasi ( November 2020 , Journal of Ecology)

   Understanding how abiotic disturbance and biotic interactions determine pollinator and flowering‐plant diversity is critically important given global climate change and widespread pollinator declines. To predict responses of pollinators and flowering‐plant communities to changes in wildfire disturbance, a mechanistic understanding of how these two trophic levels respond to wildfire severity is needed.

   We compared site‐to‐site variation in community composition (β‐diversity), species richness and abundances of pollinators and flowering plants among landscapes with no recent wildfire (unburned), mixed‐severity wildfire and high‐severity wildfire in three sites across the Northern Rockies Ecoregion, USA. We used variation partitioning to assess the relative contributions of wildfire, other abiotic variables (climate, soils and topography) and biotic associations among plant and pollinator composition to community assembly of both trophic levels.

   Wildfire disturbance generally increased species richness and total abundance, but decreasedβ‐diversity, of both pollinators and flowering plants. However, reductions inβ‐diversity from wildfire appeared to result from increased abundances following fires, resulting in higher local species richness of pollinators and flowers in burned than unburned landscapes. After accounting for differences in abundance, standardized effect sizes ofβ‐diversity were higher in burned than unburned landscapes, suggesting that wildfire enhances non‐random assortment of pollinator and flowering‐plant species among local communities.

   Wildfire disturbance mediated themore »relative importance of mutualistic associations toβ‐diversity of pollinators and flowering plants. The influence of pollinatorβ‐diversity on flowering‐plantβ‐diversity increased with wildfire severity, whereas the influence of flowering‐plantβ‐diversity on pollinatorβ‐diversity was greater in mixed‐severity than high‐severity wildfire or unburned landscapes. Moreover, biotic associations among pollinator and plant species explained substantial variation inβ‐diversity of both trophic levels beyond what could be explained by wildfire and all other abiotic and spatial factors combined.

   Synthesis. Wildfire disturbance and plant–pollinator interactions both strongly influenced the assembly of pollinator and flowering‐plant communities at local and regional scales. However, biotic interactions were generally more important drivers of community assembly in disturbed than undisturbed landscapes. As wildfire regimes continue to change globally, predicting its effects on biodiversity will require a deeper understanding of the ecological processes that mediate biotic interactions among linked trophic levels.

   « less
4. Response of Antarctic soil fauna to climate‐driven changes since the Last Glacial Maximum

   https://doi.org/10.1111/gcb.15940  

   Franco, André L. C. ; Adams, Byron J. ; Diaz, Melisa A. ; Lemoine, Nathan P. ; Dragone, Nicholas B. ; Fierer, Noah ; Lyons, W. Berry ; Hogg, Ian ; Wall, Diana H. ( October 2021 , Global Change Biology)

   Understanding how terrestrial biotic communities have responded to glacial recession since the Last Glacial Maximum (LGM) can inform present and future responses of biota to climate change. In Antarctica, the Transantarctic Mountains (TAM) have experienced massive environmental changes associated with glacial retreat since the LGM, yet we have few clues as to how its soil invertebrate‐dominated animal communities have responded. Here, we surveyed soil invertebrate fauna from above and below proposed LGM elevations along transects located at 12 features across the Shackleton Glacier region. Our transects captured gradients of surface ages possibly up to 4.5 million years and the soils have been free from human disturbance for their entire history. Our data support the hypothesis that soils exposed during the LGM are now less suitable habitats for invertebrates than those that have been exposed by deglaciation following the LGM. Our results show that faunal abundance, community composition, and diversity were all strongly affected by climate‐driven changes since the LGM. Soils more recently exposed by the glacial recession (as indicated by distances from present ice surfaces) had higher faunal abundances and species richness than older exposed soils. Higher abundances of the dominant nematodeScottnemawere found in older exposed soils, whileEudorylaimus,Plectus, tardigrades, andmore »rotifers preferentially occurred in more recently exposed soils. Approximately 30% of the soils from which invertebrates could be extracted had onlyScottnema, and these single‐taxon communities occurred more frequently in soils exposed for longer periods of time. Our structural equation modeling of abiotic drivers highlighted soil salinity as a key mediator ofScottnemaresponses to soil exposure age. These changes in soil habitat suitability and biotic communities since the LGM indicate that Antarctic terrestrial biodiversity throughout the TAM will be highly altered by climate warming.

   « less
5. Quantifying the roles of seed dispersal, filtering, and climate on regional patterns of grassland biodiversity

   https://doi.org/10.1002/ecy.3061  

   Guittar, John ; Goldberg, Deborah ; Klanderud, Kari ; Berge, Astrid ; Ramírez Boixaderas, Marta ; Meineri, Eric ; Töpper, Joachim ; Vandvik, Vigdis ( September 2020 , Ecology)

   Seed dispersal and local filtering interactively govern community membership and scale up to shape regional vegetation patterns, but data revealing how and why particular species are excluded from specific communities in nature are scarce. This lack of data is a missing link between our theoretical understanding of how diversity patterns can form and how they actually form in nature, and it hampers our ability to predict community responses to climate change. Here, we compare seed, seedling, and adult plant communities at 12 grassland sites with different climates in southern Norway to examine how community membership is interactively shaped by seed dispersal and local filtering, and how this process varies with climate across sites. To do this, we divide species at each site into two groups:locally transientspecies, which occur as seeds but are rare or absent as adults (i.e., they arrive but are filtered out), andlocally persistentspecies, which occur consistently as adults in annual vegetation surveys. We then ask how and why locally transient species are disfavored during community assembly. Our results led to four main conclusions: (1) the total numbers of seeds and species that arrived, but failed to establish locally persistent populations, rose with temperature, indicating an increasemore »in the realized effects of local filtering on community assembly, as well as an increase in the number of species poised to rapidly colonize those warmer sites if local conditions change in their favor, (2) locally transient species were selectively filtered out during seedling emergence, but not during seedling establishment, (3) selective filtering was partly driven by species climate preferences, exemplified by the poor performance of seeds dispersing outside of their realized climate niches into colder and drier foreign climates, and (4) locally transient species had traits that likely made them better dispersers (i.e., smaller seeds) but poorer competitors for light (i.e., shorter statures and less persistent clonal connections) than locally persistent species, potentially explaining why these species arrived to new sites but did not establish locally persistent adult populations. Our study is the first to combine seed, seedling, and adult survey data across sites to rigorously characterize how seed dispersal and local filtering govern community membership and shape climate‐associated vegetation patterns.

   « less