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Do seedlings in gaps interact? A field test of assumptions in ESS seed size models

Silvertown, Jonathan and Bullock, James M. (2003). Do seedlings in gaps interact? A field test of assumptions in ESS seed size models. Oikos, 101(3) pp. 499–504.

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ESS models for the evolution of seed size variation assume that seedlings compete with each other for the occupancy of 'safe sites' or vegetation gaps. If mortality rates are high and/or frequency-independent, ESS models reduce to the classical model of Smith and Fretwell which predicts that a single, optimum seed size should occur. We tested whether seedlings compete with one another by following the survival of seedlings colonizing experimental gaps in a grazed grassland community. In small gaps (3 cm diameter) the proximity of established plants slightly, though significantly reduced seedling survival, but density-dependent mortality also occurred among seedlings in these gaps. In larger gaps (6 cm, 9 cm diameter) survival was significantly positively frequency-dependent. These results strongly support the validity of ESS models.

Item Type: Journal Article
ISSN: 0030-1299
Extra Information: Visit the author's website at:
Keywords: species-poor grassland; cirsium-vulgare; tropical forest; prairie plants; community; density; recruitment; responses; colonization; germination;LW
Academic Unit/Department: Science > Environment, Earth and Ecosystems
Interdisciplinary Research Centre: Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
Item ID: 2302
Depositing User: Jonathan Silvertown
Date Deposited: 25 Sep 2006
Last Modified: 14 Jan 2016 15:47
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