A possible response of many plant species to global warming is migration to higher elevations. However, these migrations may not be required if species can tolerate higher temperatures, or may be prevented if there are other factors such as changes in soil conditions that make upslope areas unsuitable. We used a set of 3‐year field transplant experiments in the remote Peruvian Andes to simulate two possible responses of an abundant tropical montane cloudforest tree species ( We found that seedling survival and growth were not affected by changes in soil conditions, regardless of the origin population. However, seedling survival decreased with temperature. A simulated warming of 1°C caused a significant reduction in the survival of seedlings transplanted from the mid‐range population, and 2°C warming caused a severe decrease in the survival of seedlings transplanted from both the mid‐range and bottom‐edge populations.
As plant species expand their upper limits of distribution under current warming, some retain both traditional climate space and biotic environment while others encounter novel conditions. The latter is the case for
- NSF-PAR ID:
- 10441354
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecosphere
- Volume:
- 14
- Issue:
- 7
- ISSN:
- 2150-8925
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Weinmania bangii ) to global warming: (a) ‘upward migration’, in which case seedlings ofW. bangii's were grown at their current elevation/temperature but in soils transplanted from higher elevations and (b) ‘migration failure’, in which case seedlings were transplanted downslope along with their home soils into areas that are 1°C or 2°C warmer. We conducted separate experiments with populations from the upper/leading edge, middle and lower/trailing edges ofW. bangii's elevational/thermal range to assess the influence of local adaptation on responses to changes in temperature or soil.Synthesis . Our findings reveal that rising temperatures are a serious threat to plants, especially in populations growing in the hotter portion of their species’ range. At least in the case ofW. bangii, novel soil conditions will not limit the establishment or growth of seedlings at higher elevations. As such, decreases in the survivorship at lower elevations may be offset through upward migrations as temperatures continue to increase. -
Abstract Aim Climate warming is expected to drive upward and poleward shifts at the leading edge of tree species ranges. Disturbance has the potential to accelerate these shifts by altering biotic and abiotic conditions, though this potential is likely to vary by disturbance type. In this study, we assessed whether recent wildfires and spruce beetle outbreaks promoted upward range expansion of trembling aspen.
Location The San Juan Mountains of southern Colorado, USA (37°34′–37°50′N, 106°49′–107°21′W).
Taxon Populus tremuloides .Methods We used aerial imagery to determine the upper elevational limit of adult aspen and conducted seedling surveys at and above this upper limit in burned and unburned areas, which had already incurred high canopy mortality due to spruce bark beetle (
Dendroctonus rufipennis ) outbreaks. We compared characteristics of burned versus unburned bark beetle‐killed sites and assessed microsite conditions related to aspen seedling establishment using generalized linear models and interaction indices.Results Aspen seedling establishment occurred upslope of its previous range within burns, but not in unburned areas, despite severe beetle‐driven canopy mortality across all sites before the fire. Aspen seedling establishment was associated more with the light and mineral soil created by fire than the presence of nearby seed sources. Aspen seedlings were associated with nurse objects such as logs and rocks at the highest elevations, where these objects may ameliorate a range of stressors associated with the high elevation range boundary.
Main conclusions Not all disturbance types are equal in promoting tree species migrations at the leading edge. Range shifts can be highly localized, and microsites are important for driving local range expansions in transitional environments. The mosaic of future disturbances across the landscape will drive forest compositional shifts, depending on the disturbance types and the species they promote.
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Abstract Alpine treelines are expected to shift upward due to recent climate change. However, interpretation of changes in montane systems has been problematic because effects of climate change are frequently confounded with those of land use changes. The eastern Himalaya, particularly Langtang National Park, Central Nepal, has been relatively undisturbed for centuries and thus presents an opportunity for studying climate change impacts on alpine treeline uncontaminated by potential confounding factors.
We studied two dominant species,
Abies spectabilis (AS) andRhododendron campanulatum (RC) , above and below the treeline on two mountains. We constructed 13 transects, each spanning up to 400 m in elevation, in which we recorded height and state (dead or alive) of all trees, as well as slope, aspect, canopy density, and measures of anthropogenic and animal disturbance.All size classes of
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Taxon High‐elevation tree species—
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