Seed bank, seed dispersal and historical disturbance are critical factors affecting plant population persistence. However, because of difficulties collecting data on these factors they are often ignored. We evaluated the roles of seed bank, seed dispersal and historical disturbance on metapopulation persistence of The most likely model had limited dispersal (mean = 0.5 m) and the highest dormancy (field estimates × 1.2 %) and its predictions were associated with observed occurrences (67% correct) and densities (20% of variance explained). Historical burn synchrony among neighbouring patches (skewness in the number of patches burned by year = 1.79) probably explains the higher densities predicted by the simulation with the historical fire regime compared with predicted abundances after simulations using random ignition years (skewness = 0.20 +
Fluctuations in population abundances are often correlated through time across multiple locations, a phenomenon known as spatial synchrony. Spatial synchrony can exhibit complex spatial structures, termed ‘geographies of synchrony’, that can reveal mechanisms underlying population fluctuations. However, most studies have focused on spatial extents of 10s to 100s of kilometres, making it unclear how synchrony concepts and approaches should apply to dynamics at finer spatial scales. We used network analyses, multiple regression on similarity matrices, and wavelet coherence analyses to examine micro‐scale synchrony and geographies of synchrony, over distances up to 30 m, in a serpentine grassland plant community. We found that species' populations exhibited a geography of synchrony even over such short distances. Often, well‐synchronized populations were geographically separate, a spatial structure that was shaped mainly by gopher disturbance and dispersal limitation, and to a lesser extent by relationships with other plant species. Precipitation was a significant driver of site‐ and community‐wide temporal dynamics. Gopher disturbance appeared to drive synchrony on 2‐ to 6‐year timescales, and we detected coherent fluctuations among pairs of focal plant taxa.
- NSF-PAR ID:
- 10453613
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Ecology
- Volume:
- 109
- Issue:
- 2
- ISSN:
- 0022-0477
- Page Range / eLocation ID:
- p. 750-762
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary Annually variable and synchronous seed production by plant populations, or masting, is a widespread reproductive strategy in long‐lived plants. Masting is thought to be selectively beneficial because interannual variability and synchrony increase the fitness of plants through economies of scale that decrease the cost of reproduction per surviving offspring. Predator satiation is believed to be a key economy of scale, but whether it can drive phenotypic evolution for masting in plants has been rarely explored.
We used data from seven plant species (
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Q. humilis andQ. ilex ), for synchrony inQ. rubra , and for both interannual variability and reproductive synchrony inS. aucuparia andP. pinea . Predation never selected for negative temporal autocorrelation of seed production.Predation by invertebrates appears to select for only some aspects of masting, most importantly high coefficient of variation, supporting individual‐level benefits of the population‐level phenomenon of mast seeding. Determining the selective benefits of masting is complex because of interactions with other seed predators, which may impose contradictory selective pressures.
