Marine foundation species, such as corals and seagrasses, are known to provide habitats to associated organisms and enhancing both biodiversity and ecosystem functions. However, it is still unclear how increased biodiversity is related to higher ecosystem functions. In this study, we examined the spatial variation in biodiversity and ecosystem functions of dwarf eelgrass (Zostera japonica) beds along the coastline of eastern Hokkaido by analyzing effects of abiotic/biotic factors on both taxonomical and functional diversities.
Five Z. japonica meadows that were separated by 10-100 km were surveyed in September 2016. The benthic invertebrate species were collected, identified into lowest taxonomic levels, and further categorized into different functional groups based on its mobility and feeding mode. Spatial variation in taxonomic and functional diversities of animal assemblages were then analyzed in relation to abiotic factors and plant traits.
There were no statistical variation in animal species richness among meadows, whereas total abundances and diversity indices differed significantly. Variation in functional structure was most pronounced between gastropod-dominated and crustacean-dominated meadows. Observed variation can be partially explained by the combination of different abiotic and biotic factors although the pattern of correlation varied among dependent variables on taxonomic and functional diversities.