TY - JOUR
T1 - Sandification vs. muddification of tidal flats by benthic organisms: A flume study
AU - Soissons, Laura M.
AU - Gomes da Conceiçâo, Tatiana
AU - Bastiaan, John
AU - van Dalen, Jeroen
AU - Ysebaert, Tom
AU - Herman, Peter M.J.
AU - Cozzoli, Francesco
AU - Bouma, Tjeerd J.
PY - 2019/11/15
Y1 - 2019/11/15
N2 - Bioturbating benthic organisms have typically been characterised by how they modify the vertical sediment erosion thresholds. By means of several annular flume experiments, we aimed to understand how benthic organisms may affect grain-size sediment properties over time, and how this depends on the sediment type and the sediment loading of the water column. We compared the effect of two bioturbating macroinvertebrate species: a local dominant species, the cockle Cerastoderma edule and a spreading non-indigeneous species, the clam Ruditapes philippinarum. Our results indicate that the effect of benthic organisms on sediment dynamics is strongly dependent on both the prevailing environmental conditions and the benthic species present. If sediment is sandy, the benthos can gradually enhance the silt content of the sediment by mixing in part of the daily tidal sediment deposition. In contrast, if sediment is muddy, benthos can gradually decrease the silt content of the sediment by specifically suspending the fine fraction. Moreover, we observed that the native cockles had a stronger impact than invasive clams. Therefore, bioturbating benthos can have an important effect in determining the local sediment properties, with the outcome depending both on the species in question and the environmental conditions the bioturbator lives in. Our findings show that sediment bioturbation may have strong implications for tidal flat stability undergoing major changes from natural or anthropogenic sources.
AB - Bioturbating benthic organisms have typically been characterised by how they modify the vertical sediment erosion thresholds. By means of several annular flume experiments, we aimed to understand how benthic organisms may affect grain-size sediment properties over time, and how this depends on the sediment type and the sediment loading of the water column. We compared the effect of two bioturbating macroinvertebrate species: a local dominant species, the cockle Cerastoderma edule and a spreading non-indigeneous species, the clam Ruditapes philippinarum. Our results indicate that the effect of benthic organisms on sediment dynamics is strongly dependent on both the prevailing environmental conditions and the benthic species present. If sediment is sandy, the benthos can gradually enhance the silt content of the sediment by mixing in part of the daily tidal sediment deposition. In contrast, if sediment is muddy, benthos can gradually decrease the silt content of the sediment by specifically suspending the fine fraction. Moreover, we observed that the native cockles had a stronger impact than invasive clams. Therefore, bioturbating benthos can have an important effect in determining the local sediment properties, with the outcome depending both on the species in question and the environmental conditions the bioturbator lives in. Our findings show that sediment bioturbation may have strong implications for tidal flat stability undergoing major changes from natural or anthropogenic sources.
KW - Benthic organisms
KW - Cerastorderma edule
KW - Ruditapes philippinarum
KW - Sediment properties
KW - Silt content
KW - Suspended sediment concentration
KW - Tidal flats
U2 - 10.1016/j.ecss.2019.106355
DO - 10.1016/j.ecss.2019.106355
M3 - Article
AN - SCOPUS:85071437866
SN - 0272-7714
VL - 228
JO - Estuarine, Coastal and Shelf Science
JF - Estuarine, Coastal and Shelf Science
M1 - 106355
ER -