Evol Ecol Res 5: 459-468 (2003)     Full PDF if your library subscribes.

A general model for mass–growth–density relations across tree-dominated communities

Karl J. Niklas,1* Jeremy J. Midgley2 and Brian J. Enquist3

1Department of Plant Biology, Cornell University, Ithaca, NY 14853, USA, 2Department of Botany, University of Cape Town, Rondebosch 7701, South Africa and 3Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA

Author to whom all correspondence should be addressed.
e-mail: kjn2@cornell.edu


A general allometric scaling model predicts that plant body mass MT will scale as the −4/3 power of plant density N. Here, we show how this model predicts numerous other scaling attributes of plant populations and communities, including annual growth rate GT, standing leaf biomass ML, basal stem diameter D, and above- and below-ground biomass, MSH and MR. These predictions are consistent with the ‘Law of Constant Yield’ (i.e. productivity is independent of plant density). Analysis of worldwide databases for woody plant-dominated communities spanning seven orders of magnitude in MT and five orders of magnitude in N provides strong support of all of the model’s predictions. Our model thus offers a theoretical basis for understanding and predicting the effects of crowding on plant size, growth and biomass partitioning across diverse ecological communities.

Keywords: allometry, plant reproduction, scaling, self-thinning, trees.

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        © 2003 Karl J. Niklas. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

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