Fine-scale patterns of genetic variation in a widespread clonal seagrass species

Sherman, Craig D.H., York, Paul H., Smith, Timothy M., and Macreadie, Peter I. (2016) Fine-scale patterns of genetic variation in a widespread clonal seagrass species. Marine Biology, 163 (4). 82.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://dx.doi.org/10.1007/s00227-016-286...
 
9
2


Abstract

Seagrasses are ecosystem engineers that offer important habitat for a large number of species and provide a range of ecosystem services. Many seagrass ecosystems are dominated by a single species; with research showing that genotypic diversity at fine spatial scales plays an important role in maintaining a range of ecosystem functions. However, for most seagrass species, information on fine-scale patterns of genetic variation in natural populations is lacking. In this study we use a hierarchical sampling design to determine levels of genetic and genotypic diversity at different spatial scales (centimeters, meters, kilometers) in the Australian seagrass Zostera muelleri. Our analysis shows that at fine-spatial scales (<1 m) levels of genotypic diversity are relatively low (R (Plots) = 0.37 ± 0.06 SE), although there is some intermingling of genotypes. At the site (10's m) and meadow location (km) scale we found higher levels of genotypic diversity (R (sites) = 0.79 ± 0.04 SE; R (Locations) = 0.78 ± 0.04 SE). We found some sharing of genotypes between sites within meadows, but no sharing of genotypes between meadow locations. We also detected a high level of genetic structuring between meadow locations (F(ST) = 0.278). Taken together, our results indicate that both sexual and asexual reproduction are important in maintaining meadows of Z. muelleri. The dominant mechanism of asexual reproduction appears to occur via localised rhizome extension, although the sharing of a limited number of genotypes over the scale of 10's of metres could also result from the localised dispersal and recruitment of fragments. The large number of unique genotypes at the meadow scale indicates that sexual reproduction is important in maintaining these populations, while the high level of genetic structuring suggests little gene flow and connectivity between our study sites. These results imply that recovery from disturbances is will occur through both sexual and asexual regeneration, but the limited connectivity at the landscape-scale implies that recovery at meadow-scale losses is likely to be limited.

Item ID: 43093
Item Type: Article (Research - C1)
ISSN: 1432-1793
Funders: University of Technology Sydney (UTS), Australian Research Council (ARC), Deakin University (DU) Centre for Integrative Ecology
Projects and Grants: UTS Early Career Researcher Grant, Paddy Pallin Science Grant, ARC DECRA Fellowship DE130101084
Date Deposited: 23 Mar 2016 22:55
FoR Codes: 05 ENVIRONMENTAL SCIENCES > 0501 Ecological Applications > 050104 Landscape Ecology @ 50%
06 BIOLOGICAL SCIENCES > 0604 Genetics > 060411 Population, Ecological and Evolutionary Genetics @ 50%
SEO Codes: 96 ENVIRONMENT > 9609 Land and Water Management > 960903 Coastal and Estuarine Water Management @ 100%
Downloads: Total: 2
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page