Premium
Sediment properties, biota, and local habitat structure explain variation in the erodibility of coastal sediments
Author(s) -
Joensuu M.,
Pilditch C. A.,
Harris R.,
Hietanen S.,
Pettersson H.,
Norkko A.
Publication year - 2018
Publication title -
limnology and oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 197
eISSN - 1939-5590
pISSN - 0024-3590
DOI - 10.1002/lno.10622
Subject(s) - sediment , biota , abiotic component , environmental science , erosion , ecosystem , sediment transport , habitat , ecology , oceanography , hydrology (agriculture) , geology , geomorphology , biology , geotechnical engineering
Sediment resuspension is a frequent phenomenon in coastal areas and a key driver for many ecosystem functions. Sediment resuspension is often linked to biological and anthropogenic activities, which in combination with hydrodynamic forcing initiate sediment erosion and resuspension, if the erosion threshold ( τ c ) is exceeded. Despite its importance to ecosystem functions very few studies have provided measurements on natural assemblages for subtidal sediments. The aim of this study was to determinate key environmental variables regulating sediment resuspension potential across a sedimentary gradient in a subtidal coastal environment. In order to explore this, we sampled 16 sites encompassing a wide variety in environmental variables (e.g., grain size distribution, macrofaunal communities, vegetation) in the Gulf of Finland, Baltic Sea. A core‐based erosion device (EROMES) was used to determine sediment resuspension potential measures of erosion threshold, erosion rate (ER), and erosion constant ( m e ). Based on abiotic and biotic properties sampled, sediments diverged into two distinct groups; cohesive (“muddy”) and noncohesive (“sandy”) sediments. Results showed that abiotic sediment properties explained 38–53% and 15–36% of the total variation in resuspension potential measures in “muddy” and “sandy” sediments, respectively. In cumulative models, biota accounted for 12–26% and 6–24% to the total variation in “muddy” and “sandy” sediments, respectively. Sediment erodibility and resuspension potential of natural sediments is highly variable from local habitats to a larger seascape scale. Our results underline the importance of biota to resuspension potential measures in spatially variable environments.