Assessment of the Spatial and Temporal Variabilities of Phosphorus Sorption Index of the Sediments in the Maryland Coastal Bays

Abstract

Gurung, D.P.; Chen, N.; Waguespack, Y.; Ishaque, A.B., and Chigbu, P., 2022. Assessment of the spatial and temporal variabilities of phosphorus sorption index of the sediments in the Maryland Coastal Bays. Journal of Coastal Research, 38(4), 766–775. Coconut Creek (Florida), ISSN 0749-0208. Coastal bays are valuable ecosystems that can act as a sink of phosphorus (P), so it is essential to understand P sorption in sediments to investigate the dynamics of P in the coastal bays. The objectives of this study were to examine spatial and temporal variability of P sorption index (PSI) of the sediments of Maryland Coastal Bays (MCBs) and to identify factors that affect adsorption of P in sediments. Sediment samples were collected at 13 sites from 2012 to 2014 and PSI of dried sediments was measured. The PSI was comparatively higher in sediments at sites with finer particles than at sites where sediments comprised coarser particles. Water column dissolved reactive phosphorus (DRP) was significantly lower in 2013 than in 2012 throughout the MCBs. No clear pattern in spatial variation of average water column DRP occurred at each site. A positive relationship between PSI and percentage contribution of clay/silt to the sediment was observed, indicating that sediment grain size is a major factor influencing P sorption in the MCBs. Negative relationships between PSI and salinity were observed, suggesting that salinity is an important factor determining P sorption by sediment particles. There was, however, no clear influence of DRP, pH, and temperature in water column and L.Adsorp-P fraction in sediments on PSI in sediment in MCBs.