Meeting Abstract
Beach nourishment, or the emplacement of dredged sand to mitigate the effects of erosion, has become a standard method of repairing tourist beaches. One long-term effect of nourishment is a coarsening of the beach, as the finer sediments wash away quickly, leaving behind shell-hash. This is of concern, as sediment grain-size is arguably the major abiotic determinant of meiofaunal community structure. Using sieving granulometry to determine sediment parameters and DNA metabarcoding to characterize the meiofaunal community, we have examined two beaches in North Carolina, USA that differ in nourishment history. Our preliminary findings show that there is a significant difference between the two in sediment parameters, with the nourished beach having a significantly greater mean grain-size (437μm vs 218μm; p= .0013) and a greater (160μm vs 41μm), but non-significant, sorting coefficient. Analysis of alpha diversity from the metabarcoding data shows that the nourished beach exhibits significantly higher diversity in all three measures used (Faith’s PD, Chao1, and number of OTU’s). It seems possible that the increased proportion of micro-habitats in the nourished beach supports higher community diversity. This project was supported by INBRE Bioinformatics Pilot Project and INBRE RET grants to JSIII; student stipend support was provided from grant P20GM103499 (SC INBRE) from the National Institute of General Medical Sciences, National Institutes of Health.
