Searching for refuge: A framework for identifying site factors conferring resistance to climate‐driven vegetation change

Raiho, Ann; Scharf, Henry R.; Roland, Carl A.; Swanson, David K.; Stehn, Sarah E.; Hooten, Mevin B.

doi:10.1111/ddi.13492

Cited by 10 publications

(13 citation statements)

References 94 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We found pronounced topographic and edaphic gradients in conifer and shrub colonization, emphasizing the capacity of portions of boreal‐tundra landscapes to resist woody vegetation expansion (e.g. Raiho et al, 2022; Roland et al, 2016, 2021; Tape et al, 2012). Both shrub and conifer expansion appeared to depend strongly on proximity to propagules or the initial presence of some adjacent, non‐negligible cover.…”

Section: Discussionmentioning

confidence: 70%

See 1 more Smart Citation

Tree and shrub expansion at treeline drive contrasting responses in a subarctic passerine community

Mizel

Schmidt

Roland

et al. 2023

Journal of Animal Ecology

Self Cite

View full text Add to dashboard Cite

1. Inferences about the mechanisms of distributional change are often made from simple assessments of variation in the geographical positions of populations.However, direct assessments of species' responses to local habitat change may be necessary for proper understanding of the drivers of distributional dynamics.2. Amplified climate warming is inducing cascading impacts in boreal-tundra regions including the expansion of conifers and deciduous shrubs (shrubs). In Denali National Park (Denali), Alaska, passerine birds are exhibiting rapid upslope shifts in distribution but the relative roles of conifer and shrub (woody vegetation) expansion in driving these shifts are unknown. Without directly assessing passerinevegetation dynamics, the assumption has been that the observed upslope shifts are indicative of shrub-adapted passerines tracking the upslope expansion of shrubs. Here, we jointly investigate the processes of conifer and shrub expansion and their relationship to changes in passerine abundance in Denali.3. We used a remotely sensed vegetation cover timeseries to assess the topographic and edaphic correlates of conifer and shrub expansion. We then assessed the impacts of changes in shrub and conifer cover on the relative abundance of 12 passerine species (1995-2020).4. Shrub and conifer colonization rates were highest at intermediate elevations near treeline. However, forest-and shrub-adapted passerines differed in terms of the location in which their response was concentrated relative to treeline. The population growth rates of forest-adapted passerines exhibited stronger effects of woody vegetation expansion at sites that were initially above treeline (IAT). In contrast, the population growth rates of shrub-adapted passerines exhibited the negative effects of conifer expansion together with the positive effects of shrub expansion at initially below treeline sites. However, they showed a weak response to woody vegetation expansion at sites that were IAT. 5. Below treeline conifer infilling appears to be pushing the elevational distributions of shrub-adapted passerines upslope rather than these species following the pull of modest shrub expansion above treeline, as previously assumed.

show abstract

Section: Discussionmentioning

confidence: 70%

“…We found pronounced topographic and edaphic gradients in conifer and shrub colonization, emphasizing the capacity of portions of boreal-tundra landscapes to resist woody vegetation expansion (e.g. Raiho et al, 2022;Roland et al, 2016Roland et al, , 2021Tape et al, 2012).…”

Section: Discussionmentioning

confidence: 88%

Tree and shrub expansion at treeline drive contrasting responses in a subarctic passerine community

Mizel

Schmidt

Roland

et al. 2023

Journal of Animal Ecology

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, the temporal trends of both life stages were significantly positive in the Atlantic slope populations, whereas YOY trended negatively in the Interior populations. These results suggest that populations of high conservation priority should be identified with caution, and the decision should be based on multiple criteria (Raiho et al, 2022), including population temporal dynamics and sensitivity to environmental stressors.…”

Section: Discussionmentioning

confidence: 99%

Multi-scale spatial models reveal the interplay of weather and habitat effects on cold-water fish

Kanno

Valentine

et al. 2023

Preprint

View full text Add to dashboard Cite

Climate change impacts cold-water species by altering thermal and flow regimes. These impacts may vary spatially, depending on habitat quality. We developed a Bayesian hierarchical model to investigate the effects of seasonal weather patterns on brook trout (Salvelinus fontinalis) populations occupying suitable and marginal habitats separated by the Eastern Continental Divide in North Carolina, USA. We specified weather-related coefficients separately for the Interior and Atlantic slope populations. We also specified multi-scale random effects to account for heterogeneity due to nested stream habitats. Our cohesive framework accommodates depletion sampling data and allows us to infer variation in capture probabilities between two different sampling protocols. As expected, we found the Atlantic slope (i.e., marginal habitats) population sizes were smaller on average than those of the Interior (i.e., suitable habitats), and the dominant drivers differed for either side of the Divide. Specifically, juvenile fish on the Atlantic slope were most adversely affected by high winter flows, and the Interior juveniles were most adversely affected by high spring flows. We also identified higher spatial variation than temporal variation in trout density conditioned on the covariates, where the primary source of spatial heterogeneity was likely meso-habitat characteristics of stream segments. Our method allowed us to partition uncertainty between population dynamics and imperfect detection, and facilitated scale-specific inference useful to develop management strategies for a species of conservation concern. This approach is widely applicable to other lotic species and ecosystems occupying dendritic habitats.

show abstract

“…While tall shrub extent increased in all elevation quartiles during the study period, the relative increase in tall shrub extent was progressively higher through quartiles of increasing elevation. The dominant canopy‐forming species in this ecotype is feltleaf willow ( Salix alaxensis ), which occurs over broad gradients of climate on mineral‐dominated, nonacidic, well‐drained substrates that lack competing vegetation and organic material (Raiho et al, 2022; Swanson, 2015). The instrumental record indicates that mean June temperatures increased significantly (ordinary least squares regression, p < 0.05) during 1975–2010 at the three climate stations near our study streams (i.e., our full study period plus ~5 preceding years).…”

Section: Discussionmentioning

confidence: 99%

Dynamic disequilibrium: Recent widespread increases in vegetation cover on subarctic floodplains of Interior Alaska

2023

Self Cite

View full text Add to dashboard Cite

Boreal forest and tundra ecosystems are undergoing rapid climatic and environmental changes with consequences for ecosystem structure, function, and services. Although riparian zones occupy a small footprint within subarctic landscapes, they have disproportionately high value as foci of hydrological processes, biogeochemical cycling, ecological disturbance, biodiversity, and wildlife activity. Recent observations of increased winter discharge, reduced peak flows, and increased connectivity between catchments, streams, and groundwater in subarctic riparian zones have prompted predictions of altered riverine disturbance regimes, increased channelization, and a decline in the extent of active floodplains. However, few observational data exist concerning the spatiotemporal dynamics of subarctic floodplain vegetation, which can serve as a bioindicator to corroborate such predictions. We analyzed the distribution and extent of riparian ecotypes across a network of streams in 12 Interior Alaska watersheds using high-resolution image pairs from circa 1981-2010. All stream reaches encompassed pronounced elevational gradients and included elevational forest-tundra ecotones. We classified riparian ecotypes using an image-based point-intercept sampling approach, calculated the probability of ecotype transitions, and evaluated relationships between ecotype transitions and environmental covariates. Our results reveal widespread increases in the stature, density, and extent of riparian vegetation spanning gradients of elevation, floodplain morphology, and climate. Ecotype transitions occurred at >20% of sample points, and there was a strong imbalance toward forward successional transitions (16.5%) versus backward transitions (4.0%). That is, we observed a strong tendency toward increasing cover, stature, and density of vegetation communities across our extensive sampling domain across our approximately 30-year sample period. This relatively rapid riparian "greening" signal tended to be most pronounced in our glaciated watersheds.Although the streams we studied displayed high local variability in ecotype transitions, our results support hypotheses of increasing channelization and

show abstract

Searching for refuge: A framework for identifying site factors conferring resistance to climate‐driven vegetation change

Cited by 10 publications

References 94 publications

Tree and shrub expansion at treeline drive contrasting responses in a subarctic passerine community

Tree and shrub expansion at treeline drive contrasting responses in a subarctic passerine community

Multi-scale spatial models reveal the interplay of weather and habitat effects on cold-water fish

Dynamic disequilibrium: Recent widespread increases in vegetation cover on subarctic floodplains of Interior Alaska

Contact Info

Product

Resources

About