Data from: Plant community composition and species richness in the High Arctic tundra: from the present to the future

• Main Authors: Nabe-Nielsen, Jacob, Normand, Signe, Hui, Francis K. C., Stewart, Lærke, Bay, Christian, Nabe-Nielsen, Louise I., Schmidt, Niels Martin, Stewart, Laerke
• Format: Dataset
• Language: English
• Published: Dryad 2018
• Subjects: Cassiope tetragona; Silene involucrata; Pedicularis flammea; Silene acaulis; Draba arctica; carex marítima; Stellaria longipes; Euphrasia frigida; Festuca hyperborea; Luzula nivalis; Festuca brachyphylla; plant cover; Equisetum variegatum; Arctagrostis latifolia; High Arctic tundra vegetation; Bistorta vivipara; Arenaria pseudofrigida; Sabulina stricta; boral; Arnica angustifolia; Minuartia biflora; Pedicularis hirsuta; Poa glauca; Poa arctica; Potentilla nivea; Sabulina rubella; Hierochloe alpina; Cerastium arcticum; Festuca rubra; Salix arctica; Carex bigelowii; Carex fuliginosa; Juncus castaneus; Draba glabella; Rhododendron lapponicum; Micranthes nivalis; Eriophorum triste; Kobresia myosuroides; vascular plants; Potentilla rubricaulis; Carex nardina; Papaver radicatum; Saxifraga oppositifolia; Equisetum arvense; Polemonium boreale; Potentilla hyparctica; Juncus triglumis; Saxifraga cespitosa; Carex capillaris; Oxyria digyna; Arctic; Greenland; Nivea; Eriophorum; Tundra
• Online Access: https://doi.org/10.5061/dryad.8gr16

Arctic plant communities are altered by climate changes. The magnitude of these alterations depends on whether species distributions are determined by macroclimatic conditions, by factors related to local topography, or by biotic interactions. Our current understanding of the relative importance of these conditions is limited due to the scarcity of studies, especially in the High Arctic. We investigated variations in vascular plant community composition and species richness based on 288 plots distributed on three sites along a coast-inland gradient in Northeast Greenland using a stratified random design. We used an information theoretic approach to determine whether variations in species richness were best explained by macroclimate, by factors related to local topography (including soil water) or by plant-plant interactions. Latent variable models were used to explain patterns in plant community composition. Species richness was mainly determined by variations in soil water content, which explained 35% of the variation, and to a minor degree by other variables related to topography. Species richness was not directly related to macroclimate. Latent variable models showed that 23.0% of the variation in community composition was explained by variables related to topography, while distance to the inland ice explained an additional 6.4 %. This indicates that some species are associated with environmental conditions found in only some parts of the coast–inland gradient. Inclusion of macroclimatic variation increased the model's explanatory power by 4.2%. Our results suggest that the main impact of climate changes in the High Arctic will be mediated by their influence on local soil water conditions. Increasing temperatures are likely to cause higher evaporation rates and alter the distribution of late-melting snow patches. This will have little impact on landscape-scale diversity if plants are able to redistribute locally to remain in areas with sufficient soil water. Species presence in plotgroupsThe file ...