title: Plant responses to climatic extremes: within-species variation equals among-species variation.
abstract: Within-species and among-species differences in growth responses to a changing climate have been well documented, yet the relative magnitude of within-species vs. among-species variation has remained largely unexplored. This missing comparison impedes our ability to make general predictions of biodiversity change and to project future species distributions using models. We present a direct comparison of among- versus within-species variation in response to three of the main stresses anticipated with climate change: drought, warming, and frost. Two earlier experiments had experimentally induced (i) summer drought and (ii) spring frost for four common European grass species and their ecotypes from across Europe. To supplement existing data, a third experiment was carried out, to compare variation among species from different functional groups to within-species variation. Here, we simulated (iii) winter warming plus frost for four grasses, two nonleguminous, and two leguminous forbs, in addition to eleven European ecotypes of the widespread grass Arrhenatherum elatius. For each experiment, we measured: (i) C/N ratio and biomass, (ii) chlorophyll content and biomass, and (iii) plant greenness, root (15) N uptake, and live and dead tissue mass. Using coefficients of variation (CVs) for each experiment and response parameter, a total of 156 within- vs. among-species comparisons were conducted, comparing within-species variation in each of four species with among-species variation for each seed origin (five countries). Of the six significant differences, within-species CVs were higher than among-species CVs in four cases. Partitioning of variance within each treatment in two of the three experiments showed that within-species variability (ecotypes) could explain an additional 9% of response variation after accounting for the among-species variation. Our observation that within-species variation was generally as high as among-species variation emphasizes the importance of including both within- and among-species variability in ecological theory (e.g., the insurance hypothesis) and for practical applications (e.g., biodiversity conservation).
authors.affiliation: Experimental Plant Ecology, Institute of Botany and Landscape Ecology, Greifswald University, Soldmannstrasse 15, Greifswald, 17487, Germany.
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Malyshev
authors.affiliation: Disturbance Ecology, BayCEER, University of Bayreuth, Bayreuth, 95440, Germany.|Department of Forestry and Environmental Science, Shahjalal University of Science and Technology, Sylhet, 3114, Bangladesh.
authors.forename: Mohammed A S
authors.initials: MA
authors.lastname: Arfin Khan
authors.affiliation: Biogeography, BayCEER, University of Bayreuth, Bayreuth, 95440, Germany.
authors.forename: Carl
authors.initials: C
authors.lastname: Beierkuhnlein
authors.affiliation: Biogeography, BayCEER, University of Bayreuth, Bayreuth, 95440, Germany.
authors.forename: Manuel J
authors.initials: MJ
authors.lastname: Steinbauer
authors.affiliation: Department of Biology, University of Western Ontario, London, ON, N6A 5B7, Canada.
authors.forename: Hugh A L
authors.initials: HA
authors.lastname: Henry
authors.affiliation: Disturbance Ecology, BayCEER, University of Bayreuth, Bayreuth, 95440, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Jentsch
authors.affiliation: Plant Ecology, BayCEER, University of Bayreuth, Bayreuth, 95440, Germany.|German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, Leipzig, 04103, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Dengler
authors.affiliation: Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Genebank, Satellite Collections North, Malchow/Poel, 23999, Germany.
authors.forename: Evelin
authors.initials: E
authors.lastname: Willner
authors.affiliation: Experimental Plant Ecology, Institute of Botany and Landscape Ecology, Greifswald University, Soldmannstrasse 15, Greifswald, 17487, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Kreyling
mesh_terms: D000222:Adaptation, Physiological; D044822:Biodiversity; D018533:Biomass; D002244:Carbon / Q000032:analysis; D002734:Chlorophyll / Q000032:analysis; D057231:Climate Change; D055864:Droughts; D060146:Ecotype; D014644:Genetic Variation; D009584:Nitrogen / Q000032:analysis; D063245:Plant Development / Q000502:physiology*; D018517:Plant Roots / Q000378:metabolism; D010944:Plants / Q000235:genetics*; D013696:Temperature
chemical_list: D002734:Chlorophyll; D002244:Carbon; D009584:Nitrogen
keywords: disturbance; extreme climatic events; genetic diversity; inter-specific variation; intraspecific variation; niche models; provenance