Abstract
We examined temporal changes in macrofaunal α- and β-diversity over several spatial scales (within patches, among patches, across landscapes and across regions) in Long Island Sound on the northeast USA coast. Regional ε-diversity was estimated at 144 taxa, however γ-diversity fluctuated over time as did α- and β-diversity components. Based on additive partitioning, patch- and region-scale β-diversity components generally had the highest contributions to γ-diversity; lower percentages were found at within-patch and landscape scales. Multiplicative diversity partitioning indicated highest species turnover at within- and among patch scales. For all partition results, within-patch and patch-scale β-diversity increased sharply when hypoxia impacted benthic communities. Spatial variation in diversity components can be attributed to the collection of different patch types at varying spatial scales and their associated habitats across the benthic landscapes, as well as gradients in depth and other estuarine-scale characteristics. Temporal variation in diversity components across spatial scales may be related to seasonal changes in habitat heterogeneity, species population dynamics, and seasonal disturbances. Rare species were significant and temporally consistent components of macrofaunal diversity patterns over different spatial scales. Our findings agree with other marine and terrestrial studies that show diversity components vary significantly over different spatial scales and the importance of habitat/landscape heterogeneity in supporting diversity. However, our results indicate that the relative contributions of scale-specific β-diversity components can also change significantly over time. Thus, studies of diversity patterns across patches and landscapes based on data collected at one time, or assembled into a single data set from different times, may not capture the full suite of diversity patterns that occur over varying spatial scales and any time-specific determinants of those patterns. Many factors that shape and maintain sedimentary communities vary temporally, and appear to play an important role in determining and maintaining macrofaunal diversity over different spatial scales.
Highlights
Biological diversity is a central focus of ecological research, environmental management and conservation
This study focuses on how macrofaunal diversity components, a, b and c [17], vary over time across different spatial scales of benthoscape structure in a large estuarine system, using both additive and multiplicative approaches for partitioning diversity We assess patterns of species rarity across benthoscape structure
Diversity Partitioning The time-specific c-diversity in each sampling month fell below the estimated e-diversity for the entire study period, and diversity components based on additive partitioning across different scales of benthoscape structure varied considerably among sampling dates (Fig. 3)
Summary
Biological diversity is a central focus of ecological research, environmental management and conservation. Spatial patterns of soft-sediment biodiversity have been addressed to varying extent [9], our knowledge of how different aspects of benthic diversity vary over sea floor landscapes at varying scales in relation to benthic patch structure is rudimentary. Understanding how benthic biodiversity is related to benthoscape structure at different spatial scales, and how t temporal environmental variations may affect such relationships, provides a necessary framework to parse the processes determining the patterns. Biodiversity in estuaries is at high risk due to impacts from concentrated and growing levels of human development and activity [1], and acquiring a better knowledge of the patterns and dynamics of estuarine biodiversity is time sensitive as species are potentially being lost and habitats irreversibly altered in these important global environments [18]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
