Unknown

Dataset Information

0

Niches, rather than neutrality, structure a grassland pioneer guild.


ABSTRACT: Pioneer species are fast-growing, short-lived gap exploiters. They are prime candidates for neutral dynamics because they contain ecologically similar species whose low adult density is likely to cause widespread recruitment limitation, which slows competitive dynamics. However, many pioneer guilds appear to be differentiated according to seed size. In this paper, we compare predictions from a neutral model of community structure with three niche-based models in which trade-offs involving seed size form the basis of niche differentiation. We test these predictions using sowing experiments with a guild of seven pioneer species from chalk grassland. We find strong evidence for niche structure based on seed size: specifically large-seeded species produce fewer seeds but have a greater chance of establishing on a per-seed basis. Their advantage in establishment arises because there are more microsites suitable for their germination and early establishment and not directly through competition with other seedlings. In fact, seedling densities of all species were equally suppressed by the addition of competitors' seeds. By the adult stage, despite using very high sowing densities, there were no detectable effects of interspecific competition on any species. The lack of interspecific effects indicates that niche differentiation, rather than neutrality, prevails.

SUBMITTER: Turnbull LA 

PROVIDER: S-EPMC1560334 | BioStudies | 2005-01-01T00:00:00Z

REPOSITORIES: biostudies

Similar Datasets

2013-01-01 | S-EPMC3653939 | BioStudies
1000-01-01 | S-EPMC4984521 | BioStudies
2017-01-01 | S-EPMC5624504 | BioStudies
2020-01-01 | S-EPMC7793850 | BioStudies
2020-01-01 | S-EPMC6916184 | BioStudies
2013-01-01 | S-EPMC3819665 | BioStudies
2018-01-01 | S-EPMC6108313 | BioStudies
2018-01-01 | S-EPMC5792925 | BioStudies
2020-01-01 | S-EPMC7532728 | BioStudies
2014-01-01 | S-EPMC4069159 | BioStudies