Resource-based niches provide a basis for plant species diversity and dominance in arctic tundra

• Published in: Nature (London) 2002-01, Vol.415 (6867), p.68-71
• Main Authors: McKane, Robert B, Johnson, Loretta C, Shaver, Gaius R, Nadelhoffer, Knute J, Rastetter, Edward B, Fry, Brian, Giblin, Anne E, Kielland, Knut, Kwiatkowski, Bonnie L, Laundre, James A, Murray, Georgia
• Format: Article
• Language: English
• Subjects: Alaska; Animal and plant ecology; Animal, plant and microbial ecology; Arctic Regions; Biodiversity; Biological and medical sciences; Biological diversity; Biological Evolution; Biomass; Ecologists; Ecosystem; Environment; Flowers & plants; Fundamental and applied biological sciences. Psychology; Genetic Variation; Glycine - metabolism; Humanities and Social Sciences; letter; multidisciplinary; Niches; Nitrates - metabolism; Nitrogen; Nitrogen - metabolism; Plant communities; Plant diversity; Plant Physiological Phenomena; Plant species; Plants - classification; Plants - metabolism; Quaternary Ammonium Compounds - metabolism; Regions; Resource partitioning; Science; Science (multidisciplinary); Soil - analysis; Soils; Species; Species diversity; Synecology; Terrestrial ecosystems; Tundra; Tundra ecology
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/415068a

Ecologists have long been intrigued by the ways co-occurring species divide limiting resources. Such resource partitioning, or niche differentiation, may promote species diversity by reducing competition. Although resource partitioning is an important determinant of species diversity and composition in animal communities, its importance in structuring plant communities has been difficult to resolve. This is due mainly to difficulties in studying how plants compete for belowground resources. Here we provide evidence from a 15N-tracer field experiment showing that plant species in a nitrogen-limited, arctic tundra community were differentiated in timing, depth and chemical form of nitrogen uptake, and that species dominance was strongly correlated with uptake of the most available soil nitrogen forms. That is, the most productive species used the most abundant nitrogen forms, and less productive species used less abundant forms. To our knowledge, this is the first documentation that the composition of a plant community is related to partitioning of differentially available forms of a single limiting resource.