MEPS 542:97-108 (2016)  -  DOI: https://doi.org/10.3354/meps11531

Recovery pathways from small-scale disturbance in a temperate Australian seagrass

Timothy M. Smith1,5,*, Paul H. York1,2,5, Peter I. Macreadie3,4, Michael J. Keough5, D. Jeff Ross6, Craig D. H. Sherman1

1School of Life and Environmental Sciences, Centre for Integrative Ecology, Deakin University (Waurn Ponds Campus), 75 Pigdons Road. Locked Bag 20000, Geelong, VIC 3220, Australia
2Centre for Tropical Water & Aquatic Ecosystem Research (TropWATER), James Cook University, PO Box 6811, Cairns, QLD 4870, Australia
3School of Life and Environmental Sciences, Centre for Integrative Ecology, Deakin University (Burwood Campus), 221 Burwood Highway, Burwood, VIC 3125, Australia
4Plant Functional Biology and Climate Change Cluster (C3), School of the Environment, University of Technology Sydney, Broadway, NSW 2007, Australia
5School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
6Institute for Marine and Antarctic Studies, University of Tasmania, Taroona, TAS 7053, Australia
*Corresponding author:

ABSTRACT: Recovery from disturbance is a key element of ecosystem persistence, and recovery can be influenced by large-scale regional differences and smaller local-scale variations in environmental conditions. Seagrass beds are an important yet threatened nearshore habitat and recover from disturbance by regrowth, vegetative extension and dispersive propagules. We described recovery pathways from small-scale disturbances in the seagrass Zostera nigricaulis in Port Phillip Bay, a large embayment in southeastern Australia, and tested whether these pathways differed between 5 regions with different hydrodynamic conditions and water quality, and between sites within those regions. Recovery pathways were broadly consistent. When aboveground biomass was removed, recovery, defined as the point at which disturbed areas converged with undisturbed controls, took from 2 to 8 mo, but when we removed above- and below-ground biomass, it took between 2 and 13 mo. There was no evidence of recovery resulting from sexual reproduction at any sites regardless of the presence of seeds in the sediment or flower production. We found no differences in recovery at the regional scale, but we found substantial differences between local sites. At some sites, rapid recovery occurred because seagrasses grew quickly, but at others, apparent recovery occurred because regrowth coincided with overall declines in cover of undisturbed areas. Recovery time was unrelated to seagrass canopy height, biomass, percentage cover, stem density, seed bank density, epiphyte cover or sediment organic matter in seagrass adjacent to disturbance experiments. This study highlights the importance of understanding fine-scale variation in local recovery mechanisms, which may override or obscure any regional signal.


KEY WORDS: Zostera nigricaulis · Port Phillip Bay · Sexual reproduction · Asexual reproduction · Resilience · Spatial scales · Heterozostera nigricaulis


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Cite this article as: Smith TM, York PH, Macreadie PI, Keough MJ, Ross DJ, Sherman CDH (2016) Recovery pathways from small-scale disturbance in a temperate Australian seagrass. Mar Ecol Prog Ser 542:97-108. https://doi.org/10.3354/meps11531

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