Abstract
The implications of differences in plant size for seagrass productivity were examined based on an extensive compilation of data on architecture and growth of seagrass species. The analysis revealed strong allometric relationships between the size of different components, particularly a close scaling of the size of leaves, shoots, and fruits to rhizome diameter, as well as strong relationships between shoot size and the dynamics (e.g. turnover rate, plastochrone interval, and longevity) of seagrass leaves and rhizomes of different species. The decrease in rhizome elongation rates and leaf turnover rates with increasing seagrass size demonstrates the importance of architecture for seagrass productivity, and also provides explanations for the different ecological roles of small, colonizing species, and large, climax seagrass species. In addition, these results demonstrate that while habitat conditions have important influences on seagrass productivity, differences in size may explain the vast range of turnover times, plastochrone intervals, and module longevities, encountered among seagrass species.