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Tourville JC, Murray GLD, Nelson SJ. Distinct latitudinal patterns of shifting spring phenology across the Appalachian Trail Corridor. Ecology 2024:e4403. [PMID: 39205387 DOI: 10.1002/ecy.4403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 05/10/2024] [Accepted: 06/27/2024] [Indexed: 09/04/2024]
Abstract
Warming associated with climate change will advance the onset of spring phenology for many forest plants across the Eastern United States. Understory forbs and spring ephemerals that fix a disproportionate amount of carbon during early spring may be negatively affected by earlier canopy closure; however, information on the spatial patterns of phenological change for these communities is still lacking. To assess the potential for changes in spring phenological windows, we synthesized observations from the Appalachian Mountain Club's (AMCs) Mountain Watch (MW) project, the National Phenology Network (NPN), and AMC's iNaturalist projects between 2004 and 2022 (n = 118,250) across the length of the Appalachian Trail (AT) Corridor (34° N-46° N latitude). We used hierarchical Bayesian modeling to examine the sensitivity of spring flowering and leaf-out for 11 understory species and 14 canopy tree species to mean spring temperature (April-June). We conducted analyses across the AT Corridor, partitioned by regions of 4° latitude (south, mid-Atlantic, and north). Spring phenologies for both understory plants and canopy trees advanced with warming (~6 and ~3 days/°C, respectively). However, the sensitivity of each group varied by latitude, with the phenology of trees and understory plants advancing to a greater degree in the mid-Atlantic region (~10 days/°C) than in the southern or northern regions (~5 days/°C). While we find evidence that phenological windows remain stable in the southern and mid-Atlantic portions of the AT, we observed an expansion of the spring phenological window in the north where there was greater understory forb temperature sensitivity compared with trees (~2.7 days/°C). Our analyses indicate the differential sensitivity of forest plant phenology to potential warming across a large latitudinal gradient in the Eastern United States. Further, evidence for a temperature-driven expansion of the spring phenological window suggests a potential beneficial effect for understory plants in the northern AT, although phenological mismatch with potential pollinators and increased vulnerability to late winter frosts are possible. Using extensive citizen-science datasets allows us to synthesize regional- and continental-scale data to explore spatial and temporal trends in spring phenology related to warming. Such data can help to standardize approaches in phenological research and its application to forest climate resiliency.
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Pastore MA, Classen AT, D'Amato AW, English ME, Rand K, Foster JR, Adair EC. Frequent and strong cold-air pooling drives temperate forest composition. Ecol Evol 2024; 14:e11126. [PMID: 38571787 PMCID: PMC10985370 DOI: 10.1002/ece3.11126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 02/12/2024] [Accepted: 02/25/2024] [Indexed: 04/05/2024] Open
Abstract
Cold-air pooling is an important topoclimatic process that creates temperature inversions with the coldest air at the lowest elevations. Incomplete understanding of sub-canopy spatiotemporal cold-air pooling dynamics and associated ecological impacts hinders predictions and conservation actions related to climate change and cold-dependent species and functions. To determine if and how cold-air pooling influences forest composition, we characterized the frequency, strength, and temporal dynamics of cold-air pooling in the sub-canopy at local to regional scales in New England, USA. We established a network of 48 plots along elevational transects and continuously measured sub-canopy air temperatures for 6-10 months (depending on site). We then estimated overstory and understory community temperature preferences by surveying tree composition in each plot and combining these data with known species temperature preferences. We found that cold-air pooling was frequent (19-43% seasonal occurrences) and that sites with the most frequent inversions displayed inverted forest composition patterns across slopes with more cold-adapted species, namely conifers, at low instead of high elevations. We also observed both local and regional variability in cold-air pooling dynamics, revealing that while cold-air pooling is common, it is also spatially complex. Our study, which uniquely focused on broad spatial and temporal scales, has revealed some rarely reported cold-air pooling dynamics. For instance, we discovered frequent and strong temperature inversions that occurred across seasons and in some locations were most frequent during the daytime, likely affecting forest composition. Together, our results show that cold-air pooling is a fundamental ecological process that requires integration into modeling efforts predicting future forest vegetation patterns under climate change, as well as greater consideration for conservation strategies identifying potential climate refugia for cold-adapted species.
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Affiliation(s)
- Melissa A. Pastore
- Rubenstein School of Environment and Natural ResourcesUniversity of VermontBurlingtonVermontUSA
- Gund Institute for Environment, University of VermontBurlingtonVermontUSA
- USDA Forest Service, Northern Research StationSt. PaulMinnesotaUSA
| | - Aimée T. Classen
- Gund Institute for Environment, University of VermontBurlingtonVermontUSA
- Ecology and Evolutionary Biology DepartmentUniversity of MichiganAnn ArborMichiganUSA
- University of Michigan Biological StationPellstonMichiganUSA
| | - Anthony W. D'Amato
- Rubenstein School of Environment and Natural ResourcesUniversity of VermontBurlingtonVermontUSA
| | - Marie E. English
- Rubenstein School of Environment and Natural ResourcesUniversity of VermontBurlingtonVermontUSA
| | - Karin Rand
- Rubenstein School of Environment and Natural ResourcesUniversity of VermontBurlingtonVermontUSA
- Ecology and Evolutionary Biology DepartmentUniversity of MichiganAnn ArborMichiganUSA
| | - Jane R. Foster
- Rubenstein School of Environment and Natural ResourcesUniversity of VermontBurlingtonVermontUSA
- USDA Forest Service, Southern Research StationKnoxvilleTennesseeUSA
| | - E. Carol Adair
- Rubenstein School of Environment and Natural ResourcesUniversity of VermontBurlingtonVermontUSA
- Gund Institute for Environment, University of VermontBurlingtonVermontUSA
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Lu G, Fang M, Zhang S. Spatial Variation in Responses of Plant Spring Phenology to Climate Warming in Grasslands of Inner Mongolia: Drivers and Application. PLANTS (BASEL, SWITZERLAND) 2024; 13:520. [PMID: 38498495 PMCID: PMC10892319 DOI: 10.3390/plants13040520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 02/01/2024] [Accepted: 02/10/2024] [Indexed: 03/20/2024]
Abstract
Plant spring phenology in grasslands distributed in the Northern Hemisphere is highly responsive to climate warming. The growth of plants is intricately influenced by not only air temperature but also precipitation and soil factors, both of which exhibit spatial variation. Given the critical impact of the plant growth season on the livelihood of husbandry communities in grasslands, it becomes imperative to comprehend regional-scale spatial variation in the response of plant spring phenology to climate warming and the effects of precipitation and soil factors on such variation. This understanding is beneficial for region-specific phenology predictions in husbandry communities. In this study, we analyzed the spatial pattern of the correlation coefficient between the start date of the plant growth season (SOS) and the average winter-spring air temperature (WST) of Inner Mongolia grassland from 2003 to 2019. Subsequently, we analyzed the importance of 13 precipitation and soil factors for the correlation between SOS and average WST using a random forest model and analyzed the interactive effect of the important factors on the SOS using linear mixing models (LMMs). Based on these, we established SOS models using data from pastoral areas within different types of grassland. The percentage of areas with a negative correlation between SOS and average WST in meadow and typical grasslands was higher than that in desert grasslands. Results from the random forest model highlighted the significance of snow cover days (SCD), soil organic carbon (SOC), and soil nitrogen content (SNC) as influential factors affecting the correlation between SOS and average WST. Meadow grasslands exhibited significantly higher levels of SCD, SOC, and SNC compared to typical and desert grasslands. The LMMs indicated that the interaction of grassland type and the average WST and SCD can effectively explain the variation in SOS. The multiple linear models that incorporated both average WST and SCD proved to be better than models utilizing WST or SCD alone in predicting SOS. These findings indicate that the spatial patterns of precipitation and soil factors are closely associated with the spatial variation in the response of SOS to climate warming in Inner Mongolia grassland. Moreover, the average WST and SCD, when considered jointly, can be used to predict plant spring phenology in husbandry communities.
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Affiliation(s)
- Guang Lu
- Key Laboratory of Ecology and Environment in Minority Areas (National Ethnic Affairs Commission), Minzu University of China, Beijing 100081, China
- College of Life and Environment Sciences, Minzu University of China, Beijing 100081, China
| | - Mengchao Fang
- Key Laboratory of Ecology and Environment in Minority Areas (National Ethnic Affairs Commission), Minzu University of China, Beijing 100081, China
- College of Life and Environment Sciences, Minzu University of China, Beijing 100081, China
| | - Shuping Zhang
- Key Laboratory of Ecology and Environment in Minority Areas (National Ethnic Affairs Commission), Minzu University of China, Beijing 100081, China
- College of Life and Environment Sciences, Minzu University of China, Beijing 100081, China
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4
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Fragnière Y, Champoud L, Küffer N, Braillard L, Jutzi M, Wohlgemuth T, Kozlowski G. Cliff-edge forests: Xerothermic hotspots of local biodiversity and models for future climate change. GLOBAL CHANGE BIOLOGY 2024; 30:e17196. [PMID: 38404209 DOI: 10.1111/gcb.17196] [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: 10/20/2023] [Revised: 01/16/2024] [Accepted: 01/30/2024] [Indexed: 02/27/2024]
Abstract
Cliffs are remarkable environments that enable the existence of microclimates. These small, isolated sites, decoupled from the regional macroclimate, play a significant role in maintaining species biodiversity, particularly in topographically homogeneous landscapes. Our study investigated the microclimate of south-exposed forests situated at the edge of sandstone cliffs in the western part of the North Alpine Foreland Basin in Switzerland and its role in local forest community composition. Using direct measurements from data loggers, as well as vegetation analyses, it was possible to quantify the microclimate of the cliff-edge forests and compare it with that of the surrounding forests. Our results highlighted the significant xerothermic and more variable nature of the cliff-edge forest microclimate, with a mean soil temperature up to 3.72°C warmer in the summer, higher annual (+28%) and daily (+250%) amplitudes of soil temperature, which frequently expose vegetation to extreme temperatures, and an 83% higher soil drying rate. These differences have a distinct influence on forest communities: cliff-edge forests are significantly different from surrounding forests. The site particularities of cliff edges support the presence of locally rare species and forest types, particularly of Scots pine. Cliff edges must therefore be considered microrefugia with a high conservation value for both xerothermic species and flora adapted to more continental climates. Moreover, the microclimate of cliff-edge forests could resemble the future climate in many ways. We argue that these small areas, which are already experiencing the future climate, can be seen as natural laboratories to better answer the following question: what will our forests look like in a few decades with accelerated climate change?
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Affiliation(s)
- Yann Fragnière
- Department of Biology and Botanic Garden, University of Fribourg, Fribourg, Switzerland
| | - Luca Champoud
- Department of Biology and Botanic Garden, University of Fribourg, Fribourg, Switzerland
| | - Nicolas Küffer
- Department of Biology and Botanic Garden, University of Fribourg, Fribourg, Switzerland
| | - Luc Braillard
- Department of Geosciences, University of Fribourg, Fribourg, Switzerland
| | - Michael Jutzi
- Info Flora, the National Data and Information Center on the Swiss Flora, Bern, Switzerland
| | - Thomas Wohlgemuth
- Swiss Federal Institute of Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - Gregor Kozlowski
- Department of Biology and Botanic Garden, University of Fribourg, Fribourg, Switzerland
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai, China
- Natural History Museum Fribourg, Fribourg, Switzerland
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5
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Ismaeel A, Tai APK, Santos EG, Maraia H, Aalto I, Altman J, Doležal J, Lembrechts JJ, Camargo JL, Aalto J, Sam K, Avelino do Nascimento LC, Kopecký M, Svátek M, Nunes MH, Matula R, Plichta R, Abera T, Maeda EE. Patterns of tropical forest understory temperatures. Nat Commun 2024; 15:549. [PMID: 38263406 PMCID: PMC10805846 DOI: 10.1038/s41467-024-44734-0] [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: 06/28/2023] [Accepted: 01/02/2024] [Indexed: 01/25/2024] Open
Abstract
Temperature is a fundamental driver of species distribution and ecosystem functioning. Yet, our knowledge of the microclimatic conditions experienced by organisms inside tropical forests remains limited. This is because ecological studies often rely on coarse-gridded temperature estimates representing the conditions at 2 m height in an open-air environment (i.e., macroclimate). In this study, we present a high-resolution pantropical estimate of near-ground (15 cm above the surface) temperatures inside forests. We quantify diurnal and seasonal variability, thus revealing both spatial and temporal microclimate patterns. We find that on average, understory near-ground temperatures are 1.6 °C cooler than the open-air temperatures. The diurnal temperature range is on average 1.7 °C lower inside the forests, in comparison to open-air conditions. More importantly, we demonstrate a substantial spatial variability in the microclimate characteristics of tropical forests. This variability is regulated by a combination of large-scale climate conditions, vegetation structure and topography, and hence could not be captured by existing macroclimate grids. Our results thus contribute to quantifying the actual thermal ranges experienced by organisms inside tropical forests and provide new insights into how these limits may be affected by climate change and ecosystem disturbances.
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Affiliation(s)
- Ali Ismaeel
- Earth and Environmental Sciences Programme, Faculty of Science, The Chinese University of Hong Kong, Hong Kong, China
| | - Amos P K Tai
- Earth and Environmental Sciences Programme, Faculty of Science, The Chinese University of Hong Kong, Hong Kong, China
- State Key Laboratory of Agrobiotechnology, and Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | - Erone Ghizoni Santos
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
| | - Heveakore Maraia
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Branisovska 31, CZ 370 05, Czech Republic
- Faculty of Science, University of South Bohemia, Branisovska 1760, CZ 370 05, České Budějovice, Czechia
| | - Iris Aalto
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
- School of GeoSciences, University of Edinburgh, Edinburgh, EH8 9XP, UK
| | - Jan Altman
- Institute of Botany of the Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic
- Faculty of Forestry and Wood Sciences, University of Life Sciences Prague, Kamýcká 129, CZ-16521, Praha 6-Suchdol, Prague, Czech Republic
| | - Jiří Doležal
- Faculty of Science, University of South Bohemia, Branisovska 1760, CZ 370 05, České Budějovice, Czechia
- Institute of Botany of the Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic
| | - Jonas J Lembrechts
- Research Group Plants and Ecosystems, University of Antwerp, 2610, Wilrijk, Belgium
| | - José Luís Camargo
- Biological Dynamics of Forest Fragment Project (BDFFP) - National Institute of Amazonian Research (INPA), CP 478, 69067-375, Manaus, AM, Brazil
| | - Juha Aalto
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
- Finnish Meteorological Institute, P.O. Box 503, FI-00101, Helsinki, Finland
| | - Kateřina Sam
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Branisovska 31, CZ 370 05, Czech Republic
- Faculty of Science, University of South Bohemia, Branisovska 1760, CZ 370 05, České Budějovice, Czechia
| | | | - Martin Kopecký
- Institute of Botany of the Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic
- Faculty of Forestry and Wood Sciences, University of Life Sciences Prague, Kamýcká 129, CZ-16521, Praha 6-Suchdol, Prague, Czech Republic
| | - Martin Svátek
- Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, 61300, Brno, Czech Republic
| | - Matheus Henrique Nunes
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
- Department of Geographical Sciences, University of Maryland, College Park, MD, 20742, USA
| | - Radim Matula
- Faculty of Forestry and Wood Sciences, University of Life Sciences Prague, Kamýcká 129, CZ-16521, Praha 6-Suchdol, Prague, Czech Republic
| | - Roman Plichta
- Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, 61300, Brno, Czech Republic
| | - Temesgen Abera
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
- Department of Environmental Informatics, Faculty of Geography, Philipps Universität-Marburg, Deutschhausstrasse, 12, 35032, Marburg, Germany
| | - Eduardo Eiji Maeda
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland.
- Finnish Meteorological Institute, P.O. Box 503, FI-00101, Helsinki, Finland.
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Frei K, Vojtkó A, Farkas T, Erdős L, Barta K, E-Vojtkó A, Tölgyesi C, Bátori Z. Topographic depressions can provide climate and resource microrefugia for biodiversity. iScience 2023; 26:108202. [PMID: 38026156 PMCID: PMC10656275 DOI: 10.1016/j.isci.2023.108202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/30/2023] [Accepted: 10/11/2023] [Indexed: 12/01/2023] Open
Abstract
Microrefugia are often located within topographically complex regions where stable environmental conditions prevail. Most of the studies concerning the distributions of climate change-sensitive species have emphasized the dominance of cold air pooling over other environmental factors, such as resource availability. There is a shortage of information on the relationships among topography-related microsite diversity, microclimate, resource availability, and species composition in microrefugia. To fill this knowledge gap, we studied the effects of microclimatic conditions and soil resources on plant species occurrence within and adjacent to 30 large topographic depressions (i.e., dolines) in two distant karst regions. Our results showed that both microclimate and soil resource availability may play a key role in maintaining climate change-sensitive species and biodiversity in dolines; therefore, they may simultaneously act as climate and resource microrefugia. Establishing climate-smart conservation priorities and strategies is required to maintain or increase the refugial capacity of such safe havens.
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Affiliation(s)
- Kata Frei
- Department of Ecology, University of Szeged, Közép fasor 52, 6726 Szeged, Hungary
- Doctoral School of Environmental Sciences, University of Szeged, Rerrich Béla tér 1, 6720 Szeged, Hungary
| | - András Vojtkó
- Department of Botany and Plant Physiology, Eszterházy Károly Catholic University, Leányka utca 6, 3300 Eger, Hungary
| | - Tünde Farkas
- Aggtelek National Park Directorate, Tengerszem oldal 1, 3758 Jósvafő, Hungary
| | - László Erdős
- Institute of Ecology and Botany, Centre for Ecological Research, Alkotmány utca 2-4, 2163 Vácrátót, Hungary
- Department of Ecology, University of Debrecen, Egyetem tér 1, 4032 Debrecen, Hungary
| | - Károly Barta
- Department of Geoinformatics, Physical and Environmental Geography, University of Szeged, Egyetem utca 2-6, 6722 Szeged, Hungary
| | - Anna E-Vojtkó
- Institute of Botany, Czech Academy of Sciences, Dukelská 135, 379 82 Třeboň, Czech Republic
| | - Csaba Tölgyesi
- Department of Ecology, University of Szeged, Közép fasor 52, 6726 Szeged, Hungary
- MTA-SZTE ‘Lendület’ Applied Ecology Research Group, Közép fasor 52, 6726 Szeged, Hungary
- HUN-REN–UD Functional and Restoration Ecology Research Group, Egyetem tér 1, 4032 Debrecen, Hungary
| | - Zoltán Bátori
- Department of Ecology, University of Szeged, Közép fasor 52, 6726 Szeged, Hungary
- MTA-SZTE ‘Lendület’ Applied Ecology Research Group, Közép fasor 52, 6726 Szeged, Hungary
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Drews SJ, Wendel S, Leiby DA, Tonnetti L, Ushiro-Lumb I, O'Brien SF, Lieshout-Krikke RW, Bloch EM. Climate change and parasitic risk to the blood supply. Transfusion 2023; 63:638-645. [PMID: 36565251 DOI: 10.1111/trf.17234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 12/02/2022] [Accepted: 12/04/2022] [Indexed: 12/25/2022]
Affiliation(s)
- Steven J Drews
- Canadian Blood Services, Microbiology, Donation Policy and Studies, Edmonton, Alberta, Canada
- Division of Diagnostic and Applied Microbiology, Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada
| | - Silvano Wendel
- Blood Bank, Hospital Sírio-Libanês Blood Bank, São Paulo, Brazil
| | - David A Leiby
- Department of Microbiology, Immunology, & Tropical Medicine, George Washington University, Washington, DC, USA
| | - Laura Tonnetti
- American Red Cross, Scientific Affairs, Holland Laboratories for the Biomedical Sciences, Rockville, Maryland, USA
| | | | - Sheila F O'Brien
- Canadian Blood Services, Epidemiology and Surveillance, Microbiology, Ottawa, Ontario, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Ontario, Canada
| | - Ryanne W Lieshout-Krikke
- Department of Medical Affairs, Corporate Staff, Sanquin Blood Supply Foundation, Amsterdam, the Netherlands
| | - Evan M Bloch
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Finocchiaro M, Médail F, Saatkamp A, Diadema K, Pavon D, Meineri E. Bridging the gap between microclimate and microrefugia: A bottom-up approach reveals strong climatic and biological offsets. GLOBAL CHANGE BIOLOGY 2023; 29:1024-1036. [PMID: 36383061 PMCID: PMC10100396 DOI: 10.1111/gcb.16526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 10/11/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
In the context of global warming, a clear understanding of microrefugia-microsites enabling the survival of species populations outside their main range limits-is crucial. Several studies have identified forcing factors that are thought to favor the existence of microrefugia. However, there is a lack of evidence to conclude whether, and to what extent, the climate encountered within existing microrefugia differs from the surrounding climate. To investigate this, we adopt a "bottom-up" approach, linking marginal disconnected populations to microclimate. We used the southernmost disconnected and abyssal populations of the circumboreal herbaceous plant Oxalis acetosella in Southern France to study whether populations in sites matching the definition of "microrefugia" occur in particularly favorable climatic conditions compared to neighboring control plots located at distances of between 50 to 100 m. Temperatures were recorded in putative microrefugia and in neighboring plots for approximately 2 years to quantify their thermal offsets. Vascular plant inventories were carried out to test whether plant communities also reflect microclimatic offsets. We found that current microclimatic dynamics are genuinely at stake in microrefugia. Microrefugia climates are systematically colder compared to those found in neighboring control plots. This pattern was more noticeable during the summer months. Abyssal populations showed stronger offsets compared to neighboring plots than the putative microrefugia occurring at higher altitudes. Plant communities demonstrate this strong spatial climatic variability, even at such a microscale approach, as species compositions systematically differed between the two plots, with species more adapted to colder and moister conditions in microrefugia compared to the surrounding area.
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Affiliation(s)
- Marie Finocchiaro
- Aix Marseille Université, Avignon Université, CNRS, IRD, UMR IMBEMarseilleFrance
| | - Frédéric Médail
- Aix Marseille Université, Avignon Université, CNRS, IRD, UMR IMBEMarseilleFrance
| | - Arne Saatkamp
- Aix Marseille Université, Avignon Université, CNRS, IRD, UMR IMBEMarseilleFrance
| | - Katia Diadema
- Conservatoire Botanique National Méditerranéen de PorquerollesHyèresFrance
| | - Daniel Pavon
- Aix Marseille Université, Avignon Université, CNRS, IRD, UMR IMBEMarseilleFrance
| | - Eric Meineri
- Aix Marseille Université, Avignon Université, CNRS, IRD, UMR IMBEMarseilleFrance
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