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Ainsworth A, Drake DR. Hawaiian Treeline Ecotones: Implications for Plant Community Conservation under Climate Change. PLANTS (BASEL, SWITZERLAND) 2023; 13:123. [PMID: 38202431 PMCID: PMC10780311 DOI: 10.3390/plants13010123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 12/15/2023] [Accepted: 12/24/2023] [Indexed: 01/12/2024]
Abstract
Species within tropical alpine treeline ecotones are predicted to be especially sensitive to climate variability because this zone represents tree species' altitudinal limits. Hawaiian volcanoes have distinct treeline ecotones driven by trade wind inversions. The local climate is changing, but little is known about how this influences treeline vegetation. To predict future impacts of climate variability on treelines, we must define the range of variation in treeline ecotone characteristics. Previous studies highlighted an abrupt transition between subalpine grasslands and wet forest on windward Haleakalā, but this site does not represent the diversity of treeline ecotones among volcanoes, lava substrates, and local climatic conditions. To capture this diversity, we used data from 225 plots spanning treelines (1500-2500 m) on Haleakalā and Mauna Loa to characterize ecotonal plant communities. Treeline indicator species differ by moisture and temperature, with common native species important for wet forest, subalpine woodland, and subalpine shrubland. The frequency or abundance of community indicator species may be better predictors of shifting local climates than the presence or absence of tree life forms per se. This study further supports the hypothesis that changes in available moisture, rather than temperature, will dictate the future trajectory of Hawaiian treeline ecotone communities.
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Affiliation(s)
- Alison Ainsworth
- School of Life Sciences, University of Hawai’i at Mānoa, Honolulu, HI 96822, USA;
- National Park Service, Pacific Island Inventory and Monitoring Network, Hawaii National Park, HI 96718, USA
| | - Donald R. Drake
- School of Life Sciences, University of Hawai’i at Mānoa, Honolulu, HI 96822, USA;
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2
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Feeley KJ, Bernal-Escobar M, Fortier R, Kullberg AT. Tropical Trees Will Need to Acclimate to Rising Temperatures-But Can They? PLANTS (BASEL, SWITZERLAND) 2023; 12:3142. [PMID: 37687387 PMCID: PMC10490527 DOI: 10.3390/plants12173142] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/10/2023]
Abstract
For tropical forests to survive anthropogenic global warming, trees will need to avoid rising temperatures through range shifts and "species migrations" or tolerate the newly emerging conditions through adaptation and/or acclimation. In this literature review, we synthesize the available knowledge to show that although many tropical tree species are shifting their distributions to higher, cooler elevations, the rates of these migrations are too slow to offset ongoing changes in temperatures, especially in lowland tropical rainforests where thermal gradients are shallow or nonexistent. We also show that the rapidity and severity of global warming make it unlikely that tropical tree species can adapt (with some possible exceptions). We argue that the best hope for tropical tree species to avoid becoming "committed to extinction" is individual-level acclimation. Although several new methods are being used to test for acclimation, we unfortunately still do not know if tropical tree species can acclimate, how acclimation abilities vary between species, or what factors may prevent or facilitate acclimation. Until all of these questions are answered, our ability to predict the fate of tropical species and tropical forests-and the many services that they provide to humanity-remains critically impaired.
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Affiliation(s)
- Kenneth J. Feeley
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA; (M.B.-E.); (R.F.); (A.T.K.)
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3
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Mata-Guel EO, Soh MCK, Butler CW, Morris RJ, Razgour O, Peh KSH. Impacts of anthropogenic climate change on tropical montane forests: an appraisal of the evidence. Biol Rev Camb Philos Soc 2023; 98:1200-1224. [PMID: 36990691 DOI: 10.1111/brv.12950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 03/08/2023] [Accepted: 03/10/2023] [Indexed: 03/31/2023]
Abstract
In spite of their small global area and restricted distributions, tropical montane forests (TMFs) are biodiversity hotspots and important ecosystem services providers, but are also highly vulnerable to climate change. To protect and preserve these ecosystems better, it is crucial to inform the design and implementation of conservation policies with the best available scientific evidence, and to identify knowledge gaps and future research needs. We conducted a systematic review and an appraisal of evidence quality to assess the impacts of climate change on TMFs. We identified several skews and shortcomings. Experimental study designs with controls and long-term (≥10 years) data sets provide the most reliable evidence, but were rare and gave an incomplete understanding of climate change impacts on TMFs. Most studies were based on predictive modelling approaches, short-term (<10 years) and cross-sectional study designs. Although these methods provide moderate to circumstantial evidence, they can advance our understanding on climate change effects. Current evidence suggests that increasing temperatures and rising cloud levels have caused distributional shifts (mainly upslope) of montane biota, leading to alterations in biodiversity and ecological functions. Neotropical TMFs were the best studied, thus the knowledge derived there can serve as a proxy for climate change responses in under-studied regions elsewhere. Most studies focused on vascular plants, birds, amphibians and insects, with other taxonomic groups poorly represented. Most ecological studies were conducted at species or community levels, with a marked paucity of genetic studies, limiting understanding of the adaptive capacity of TMF biota. We thus highlight the long-term need to widen the methodological, thematic and geographical scope of studies on TMFs under climate change to address these uncertainties. In the short term, however, in-depth research in well-studied regions and advances in computer modelling approaches offer the most reliable sources of information for expeditious conservation action for these threatened forests.
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Affiliation(s)
- Erik O Mata-Guel
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Malcolm C K Soh
- National Park Boards, 1 Cluny Road, Singapore, 259569, Singapore
| | - Connor W Butler
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Rebecca J Morris
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Orly Razgour
- Biosciences, University of Exeter, Exeter, EX4 4PS, UK
| | - Kelvin S-H Peh
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
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Kullberg AT, Feeley KJ. Limited acclimation of leaf traits and leaf temperatures in a subtropical urban heat island. TREE PHYSIOLOGY 2022; 42:2266-2281. [PMID: 35708568 DOI: 10.1093/treephys/tpac066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 06/11/2022] [Indexed: 06/15/2023]
Abstract
The consequences of rising temperatures for trees will vary between species based on their abilities to acclimate their leaf thermoregulatory traits and photosynthetic thermal tolerances. We tested the hypotheses that adult trees in warmer growing conditions (i) acclimate their thermoregulatory traits to regulate leaf temperatures, (ii) acclimate their thermal tolerances such that tolerances are positively correlated with leaf temperature and (iii) that species with broader thermal niche breadths have greater acclimatory abilities. To test these hypotheses, we measured leaf traits and thermal tolerances of seven focal tree species across steep thermal gradients in Miami's urban heat island. We found that some functional traits varied significantly across air temperatures within species. For example, leaf thickness increased with maximum air temperature in three species, and leaf mass per area and leaf reflectance both increased with air temperature in one species. Only one species was marginally more homeothermic than expected by chance due to acclimation of its thermoregulatory traits, but this acclimation was insufficient to offset elevated air temperatures. Thermal tolerances acclimated to higher maximum air temperatures in two species. As a result of limited acclimation, leaf thermal safety margins (TSMs) were narrower for trees in hotter areas. We found some support for our hypothesis that species with broader thermal niches are better at acclimating to maintain more stable TSMs across the temperature gradients. These findings suggest that trees have limited abilities to acclimate to high temperatures and that thermal niche specialists may be at a heightened risk of thermal stress as global temperatures continue to rise.
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Affiliation(s)
- Alyssa T Kullberg
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
| | - Kenneth J Feeley
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
- Fairchild Tropical Botanic Garden, Coral Gables, FL 33156, USA
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5
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Muñoz Mazón M, Klanderud K, Sheil D. Canopy openness modifies tree seedling distributions along a tropical forest elevation gradient. OIKOS 2022. [DOI: 10.1111/oik.09205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Miguel Muñoz Mazón
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian Univ. of Life Sciences (NMBU) Ås Norway
| | - Kari Klanderud
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian Univ. of Life Sciences (NMBU) Ås Norway
| | - Douglas Sheil
- Forest Ecology and Forest Management Group, Wageningen Univ. and Research Wageningen the Netherlands
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6
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Chen W, Ding H, Li J, Chen K, Wang H. Alpine treelines as ecological indicators of global climate change: Who has studied? What has been studied? ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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7
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Marcora PI, Tecco PA, Ferrero MC, Ferreras AE, Zeballos SR, Funes G, Gurvich DE, Arias G, Cáceres Y, Hensen I. Are populations of Polylepis australis locally adapted along their elevation gradient? NEOTROPICAL BIODIVERSITY 2021. [DOI: 10.1080/23766808.2021.1940049] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Paula Inés Marcora
- Instituto Multidisciplinario De Biología Vegetal (Conicet-universidad Nacional de Córdoba), Cordoba, Argentina
| | - Paula A Tecco
- Instituto Multidisciplinario De Biología Vegetal (Conicet-universidad Nacional de Córdoba), Cordoba, Argentina
- Cátedra de Biogeografía, Departamento de Diversidad Biológica y Ecológica, Facultad de Ciencias Exactas, Físicas y Naturales, Cordoba, Argentina
| | - María Cecilia Ferrero
- Instituto Multidisciplinario De Biología Vegetal (Conicet-universidad Nacional de Córdoba), Cordoba, Argentina
| | - Ana Elisa Ferreras
- Instituto Multidisciplinario De Biología Vegetal (Conicet-universidad Nacional de Córdoba), Cordoba, Argentina
| | - Sebastián Rodolfo Zeballos
- Instituto Multidisciplinario De Biología Vegetal (Conicet-universidad Nacional de Córdoba), Cordoba, Argentina
| | - Guillermo Funes
- Instituto Multidisciplinario De Biología Vegetal (Conicet-universidad Nacional de Córdoba), Cordoba, Argentina
- Cátedra de Biogeografía, Departamento de Diversidad Biológica y Ecológica, Facultad de Ciencias Exactas, Físicas y Naturales, Cordoba, Argentina
| | - Diego Ezequiel Gurvich
- Instituto Multidisciplinario De Biología Vegetal (Conicet-universidad Nacional de Córdoba), Cordoba, Argentina
- Cátedra de Biogeografía, Departamento de Diversidad Biológica y Ecológica, Facultad de Ciencias Exactas, Físicas y Naturales, Cordoba, Argentina
| | - Gonzalo. Arias
- Cátedra de Biogeografía, Departamento de Diversidad Biológica y Ecológica, Facultad de Ciencias Exactas, Físicas y Naturales, Cordoba, Argentina
| | - Yolanda Cáceres
- Martin Luther University Halle-Wittenberg, Institute of Biology/Geobotany and Botanical Garden, Halle (Saale), Germany
- German Centre for Integrative Biodiversity Research (Idiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Isabell Hensen
- Martin Luther University Halle-Wittenberg, Institute of Biology/Geobotany and Botanical Garden, Halle (Saale), Germany
- German Centre for Integrative Biodiversity Research (Idiv) Halle-Jena-Leipzig, Leipzig, Germany
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Caballero-Villalobos L, Fajardo-Gutiérrez F, Calbi M, Silva-Arias GA. Climate Change Can Drive a Significant Loss of Suitable Habitat for Polylepis quadrijuga, a Treeline Species in the Sky Islands of the Northern Andes. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.661550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
It is predicted that climate change will strongly affect plant distributions in high elevation “sky islands” of tropical Andes. Polylepis forests are a dominant element of the treeline throughout the Andes Cordillera in South America. However, little is known about the climatic factors underlying the current distribution of Polylepis trees and the possible effect of global climate change. The species Polylepis quadrijuga is endemic to the Colombian Eastern Cordillera, where it plays a fundamental ecological role in high-altitude páramo-forest ecotones. We sought to evaluate the potential distribution of P. quadrijuga under future climate change scenarios using ensemble modeling approaches. We conducted a comprehensive assessment of future climatic projections deriving from 12 different general circulation models (GCMs), four Representative Concentration Pathways (R) emissions scenarios, and two different time frames (2041–2060 and 2061–2080). Additionally, based on the future projections, we evaluate the effectiveness of the National System of Protected Natural Areas of Colombia (SINAP) and Páramo Complexes of Colombia (PCC) in protecting P. quadrijuga woodlands. Here, we compiled a comprehensive set of observations of P. quadrijuga and study them in connection with climatic and topographic variables to identify environmental predictors of the species distribution, possible habitat differentiation throughout the geographic distribution of the species, and predict the effect of different climate change scenarios on the future distribution of P. quadrijuga. Our results predict a dramatic loss of suitable habitat due to climate change on this key tropical Andean treeline species. The ensemble Habitat Suitability Modeling (HSM) shows differences in suitable scores among north and south regions of the species distribution consistent with differences in topographic features throughout the available habitat of P. quadrijuga. Future projections of the HSM predicted the Páramo complex “Sumapaz-Cruz Verde” as a major area for the long-term conservation of P. quadrijuga because it provides a wide range of suitable habitats for the different evaluated climate change scenarios. We provide the first set of priority areas to perform both in situ and ex situ conservation efforts based on suitable habitat projections.
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Freezing temperatures restrict woody plant recruitment and restoration efforts in abandoned montane pastures. Glob Ecol Conserv 2021. [DOI: 10.1016/j.gecco.2021.e01462] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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10
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Yang Y, Sun H, Körner C. Explaining the exceptional 4270 m high elevation limit of an evergreen oak in the south-eastern Himalayas. TREE PHYSIOLOGY 2020; 40:1327-1342. [PMID: 32483630 DOI: 10.1093/treephys/tpaa070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 06/02/2020] [Indexed: 05/26/2023]
Abstract
Unlike the well-understood alpine treeline, the upper range limits of tree taxa that do not reach the alpine treeline are largely unexplained. In this study, we explored the causes of the exceptionally high elevation (4270 m) occurrence of broad-leaved evergreen oaks (Quercus pannosa) in the south-eastern Himalayas. We assessed the course of freezing resistance of buds and leaves from winter to summer at the upper elevational limit of this oak species. Linked to leaf phenology, we analyzed freezing resistance and assessed minimum crown temperature for the past 65 years. We also examined potential carbon limitation at the range limit of this species. Last season buds and leaves operated at a safety margin of 5.5 and 11 K in mid-winter. Once fully dehardened early in July, last season foliage is damaged at -5.9 and new foliage at -4.6 °C. Bud break is timed for late June to early July when low temperature extremes historically were never below -3.0 °C. The monsoon regime ensures a long remaining season (149 days), thus compensating for the late onset of shoot growth. Compared with a site at 3450 m, specific leaf area is reduced, foliar non-structural carbohydrate concentrations are similar and the δ13C signal is higher, jointly suggesting that carbon limitation is unlikely at the range limit of this species. We also show that these oaks enter the growing season with fully intact (not embolized) xylem. We conclude that the interaction between phenology and freezing tolerance results in safe flushing, while still facilitating shoot maturation before winter. These factors jointly determine the upper range limit of this oak species. Our study illuminates an exceptional case of broad-leaved evergreen tree performance near the treeline, and by exploring a suite of traits, we can underpin the central role of flushing phenology in such a stressful environment.
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Affiliation(s)
- Yang Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Lanhei Road 132, Kunming, Yunnan 650204, PR China
| | - Hang Sun
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Lanhei Road 132, Kunming, Yunnan 650204, PR China
| | - Christian Körner
- Institute of Botany, University of Basel, Schönbeinstrasse 6, Basel 4056, Switzerland
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11
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Is there potential in elevational assisted migration for the endangered Magnolia vovidesii? J Nat Conserv 2020. [DOI: 10.1016/j.jnc.2019.125782] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Muñoz Mazón M, Klanderud K, Finegan B, Veintimilla D, Bermeo D, Murrieta E, Delgado D, Sheil D. Disturbance and the elevation ranges of woody plant species in the mountains of Costa Rica. Ecol Evol 2019; 9:14330-14340. [PMID: 31938522 PMCID: PMC6953661 DOI: 10.1002/ece3.5870] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/20/2019] [Accepted: 08/29/2019] [Indexed: 11/10/2022] Open
Abstract
AIM To understand how disturbance-here defined as a transient reduction in competition-can shape plant distributions along elevation gradients. Theory suggests that disturbance may increase elevation ranges, especially at the lower range limits, through reduced competitive exclusion. Nevertheless, to date this relationship remains unclear. LOCATION Mountains of Costa Rica. METHODS We compared the elevation range of woody stems over 10 cm dbh ("trees") observed in plots along two transects spanning a range of elevations in secondary (regrowth) and old-growth forest (409 and 249 species, respectively). We also estimated these elevation ranges using nationwide data. In addition, we examined the influence of stem size and plot scale basal area (as a measure of competition) on species elevation range limits in the two gradients. RESULTS In general, tree species ranges increased with elevation. Species in the secondary forest had broader elevation ranges (100-318 m broader than species in the old-growth forest; Wilcoxon: p-value <.001). Also, in the secondary transect, individuals with greater diameters had broader elevation ranges than those observed as smaller trees (137 m broader; Kruskal-Wallis: p-value = .03). The lower range limit of species occurred more frequently in plots with lower (vs. higher) basal area than expected by chance in both forest types. We also observed higher elevation upper limits in old growth, but not in secondary forests, with lower (vs. higher) basal area. MAIN CONCLUSION Disturbance relaxes the constraints imposed by competition and extends effective elevation ranges of species, particularly those in secondary forest, to warmer and cooler climates (minimum increase equivalent to about 0.6-1.4°C). Thus, suitable disturbance may assist species persistence under climate change. We believe this is the first study indicating a consistent relation between disturbance and woody plant species distributions along elevation gradients.
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Affiliation(s)
- Miguel Muñoz Mazón
- Faculty of Environmental Sciences and Natural Resource ManagementNorwegian University of Life Sciences (NMBU)ÅsNorway
| | - Kari Klanderud
- Faculty of Environmental Sciences and Natural Resource ManagementNorwegian University of Life Sciences (NMBU)ÅsNorway
| | - Bryan Finegan
- CATIE‐Centro Agronómico Tropical de Investigación y EnseñanzaTurrialbaCosta Rica
| | - Darío Veintimilla
- CATIE‐Centro Agronómico Tropical de Investigación y EnseñanzaTurrialbaCosta Rica
- Johann Heinrich von Thünen Institute Federal Research Institute for Rural Areas, Forestry and FisheriesBraunschweigGermany
| | - Diego Bermeo
- CATIE‐Centro Agronómico Tropical de Investigación y EnseñanzaTurrialbaCosta Rica
| | - Eduardo Murrieta
- CATIE‐Centro Agronómico Tropical de Investigación y EnseñanzaTurrialbaCosta Rica
| | - Diego Delgado
- CATIE‐Centro Agronómico Tropical de Investigación y EnseñanzaTurrialbaCosta Rica
| | - Douglas Sheil
- Faculty of Environmental Sciences and Natural Resource ManagementNorwegian University of Life Sciences (NMBU)ÅsNorway
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Fadrique B, Báez S, Duque Á, Malizia A, Blundo C, Carilla J, Osinaga-Acosta O, Malizia L, Silman M, Farfán-Ríos W, Malhi Y, Young KR, Cuesta C. F, Homeier J, Peralvo M, Pinto E, Jadan O, Aguirre N, Aguirre Z, Feeley KJ. Widespread but heterogeneous responses of Andean forests to climate change. Nature 2018; 564:207-212. [DOI: 10.1038/s41586-018-0715-9] [Citation(s) in RCA: 125] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 09/17/2018] [Indexed: 11/09/2022]
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14
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Davis EL, Gedalof Z. Limited prospects for future alpine treeline advance in the Canadian Rocky Mountains. GLOBAL CHANGE BIOLOGY 2018; 24:4489-4504. [PMID: 29856111 DOI: 10.1111/gcb.14338] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 05/24/2018] [Accepted: 05/26/2018] [Indexed: 06/08/2023]
Abstract
Treeline advance has occurred throughout the twentieth century in mountainous regions around the world; however, local variation and temporal lags in responses to climate warming indicate that the upper limits of some treelines are not necessarily in climatic equilibrium. These observations suggest that factors other than climate are constraining tree establishment beyond existing treelines. Using a seed addition experiment, we tested the effects of seed availability, predation and microsite limitation on the establishment of two subalpine tree species (Picea engelmannii and Abies lasiocarpa) across four treelines in the Canadian Rocky Mountains. The effect of vegetation removal on seedling growth was also determined, and microclimate conditions were monitored. Establishment limitations observed in the field were placed in context with the effects of soil properties observed in a parallel experiment. The seed addition experiment revealed reduced establishment with increasing elevation, suggesting that although establishment within the treeline ecotone is at least partially seed limited, other constraints are more important beyond the current treeline. The effects of herbivory and microsite availability significantly reduced seedling establishment but were less influential beyond the treeline. Microclimate monitoring revealed that establishment was negatively related to growing season temperatures and positively related to the duration of winter snow cover, counter to the conventional expectation that establishment is limited by low temperatures. Overall, it appears that seedling establishment beyond treeline is predominantly constrained by a combination of high soil surface temperatures during the growing season, reduced winter snowpack and unfavourable soil properties. Our study supports the assertion that seedling establishment in alpine treeline ecotones is simultaneously limited by various climatic and nonclimatic drivers. Together, these factors may limit future treeline advance in the Canadian Rocky Mountains and should be considered when assessing the potential for treeline advance in alpine systems elsewhere.
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Affiliation(s)
- Emma L Davis
- Department of Geography, University of Guelph, Guelph, ON, Canada
| | - Ze'ev Gedalof
- Department of Geography, University of Guelph, Guelph, ON, Canada
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15
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Morales LV, Sevillano‐Rios CS, Fick S, Young TP. Differential seedling regeneration patterns across forest–grassland ecotones in two tropical treeline species (
Polylepis
spp.). AUSTRAL ECOL 2018. [DOI: 10.1111/aec.12588] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Laura V. Morales
- Department of Plant Sciences and Graduate Group in Ecology University of California, Davis Davis California 95616USA
| | | | - Stephen Fick
- Stockholm Environment Institute Stockholm Sweden
| | - Truman P. Young
- Department of Plant Sciences and Graduate Group in Ecology University of California, Davis Davis California 95616USA
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16
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Báez S, Jaramillo L, Cuesta F, Donoso DA. Effects of climate change on Andean biodiversity: a synthesis of studies published until 2015. NEOTROPICAL BIODIVERSITY 2016. [DOI: 10.1080/23766808.2016.1248710] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Selene Báez
- Consorcio para el Desarrollo Sostenible de la Ecoregion Andina, Lima, Peru
- Instituto de Ciencias Biológicas, Escuela Politécnica Nacional, Quito, Ecuador
| | - Liliana Jaramillo
- Departamento de Ciencias Naturales, Universidad Técnica Particular de Loja, Loja, Ecuador
| | - Francisco Cuesta
- Consorcio para el Desarrollo Sostenible de la Ecoregion Andina, Lima, Peru
- Institute for Biodiversity & Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, The Netherlands
| | - David A. Donoso
- Departamento de Ciencias Naturales, Universidad Técnica Particular de Loja, Loja, Ecuador
- Facultad de Ciencias Agropecuarias, Universidad de Cuenca, Cuenca, Ecuador
- Instituto de Ciencias Biológicas, Escuela Politécnica Nacional, Quito, Ecuador
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17
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Wang X, Liu H, Gu M, Boucek R, Wu Z, Zhou G. Greater impacts from an extreme cold spell on tropical than temperate butterflies in southern China. Ecosphere 2016. [DOI: 10.1002/ecs2.1315] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Xu Wang
- Research Institute of Tropical Forestry Chinese Academy of Forestry Guangzhou 510520 China
| | - Hong Liu
- College of Forestry Guangxi University Nanning China
- Department of Earth and Environment and International Center for Tropical Botany Florida International University Miami Florida 33199 USA
| | - Mao‐Bin Gu
- Research Institute of Tropical Forestry Chinese Academy of Forestry Guangzhou 510520 China
| | - Ross Boucek
- Department of Earth and Environment and International Center for Tropical Botany Florida International University Miami Florida 33199 USA
| | - Zhong‐Min Wu
- Research Institute of Tropical Forestry Chinese Academy of Forestry Guangzhou 510520 China
| | - Guang‐Yi Zhou
- Research Institute of Tropical Forestry Chinese Academy of Forestry Guangzhou 510520 China
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Seedling transplants reveal species-specific responses of high-elevation tropical treeline trees to climate change. Oecologia 2016; 181:1233-42. [PMID: 27071667 DOI: 10.1007/s00442-016-3619-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 03/20/2016] [Indexed: 10/22/2022]
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Case BS, Buckley HL. Local-scale topoclimate effects on treeline elevations: a country-wide investigation of New Zealand's southern beech treelines. PeerJ 2015; 3:e1334. [PMID: 26528407 PMCID: PMC4627911 DOI: 10.7717/peerj.1334] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 09/29/2015] [Indexed: 11/20/2022] Open
Abstract
Although treeline elevations are limited globally by growing season temperature, at regional scales treelines frequently deviate below their climatic limit. The cause of these deviations relate to a host of climatic, disturbance, and geomorphic factors that operate at multiple scales. The ability to disentangle the relative effects of these factors is currently hampered by the lack of reliable topoclimatic data, which describe how regional climatic characteristics are modified by topographic effects in mountain areas. In this study we present an analysis of the combined effects of local- and regional-scale factors on southern beech treeline elevation variability at 28 study areas across New Zealand. We apply a mesoscale atmospheric model to generate local-scale (200 m) meteorological data at these treelines and, from these data, we derive a set of topoclimatic indices that reflect possible detrimental and ameliorative influences on tree physiological functioning. Principal components analysis of meteorological data revealed geographic structure in how study areas were situated in multivariate space along gradients of topoclimate. Random forest and conditional inference tree modelling enabled us to tease apart the relative effects of 17 explanatory factors on local-scale treeline elevation variability. Overall, modelling explained about 50% of the variation in treeline elevation variability across the 28 study areas, with local landform and topoclimatic effects generally outweighing those from regional-scale factors across the 28 study areas. Further, the nature of the relationships between treeline elevation variability and the explanatory variables were complex, frequently non-linear, and consistent with the treeline literature. To our knowledge, this is the first study where model-generated meteorological data, and derived topoclimatic indices, have been developed and applied to explain treeline variation. Our results demonstrate the potential of such an approach for ecological research in mountainous environments.
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Affiliation(s)
- Bradley S Case
- Department of Informatics and Enabling Technologies, Lincoln University , Lincoln, Canterbury , New Zealand
| | - Hannah L Buckley
- Department of Ecology, Lincoln University , Lincoln, Canterbury , New Zealand
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