The dynamics of suspended particulate matter (SPM) and chlorophyll- a from intratidal to annual time scales in a coastal turbidity maximum
van der Hout, C.M.; Witbaard, R.; Bergman, M.J.N.; Duineveld, G.C.A.; Rozemeijer, M.J.C.; Gerkema, T. (2017). The dynamics of suspended particulate matter (SPM) and chlorophyll- a from intratidal to annual time scales in a coastal turbidity maximum. J. Sea Res. 127: 105-118. https://dx.doi.org/10.1016/j.seares.2017.04.011 In: Journal of Sea Research. Elsevier/Netherlands Institute for Sea Research: Amsterdam; Den Burg. ISSN 1385-1101; e-ISSN 1873-1414, more | |
Author keywords | Wave climate; In-situ observations; Bed shear stress; SPM; Chlorophyll-a; Season |
Authors | | Top | - van der Hout, C.M., more
- Witbaard, R., more
- Bergman, M.J.N., more
| - Duineveld, G.C.A., more
- Rozemeijer, M.J.C.
- Gerkema, T., more
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Abstract | The analysis of 1.8 years of data gives an understanding of the response to varying forcing of suspended particulate matter (SPM) and chlorophyll-a (CHL-a) in a coastal turbidity maximum zone (TMZ). Both temporal and vertical concentration variations in the near-bed layer (0–2 m) in the shallow (11 m deep) coastal zone at 1 km off the Dutch coast are shown. Temporal variations in the concentration of both parameters are found on tidal and seasonal scales, and a marked response to episodic events (e.g. storms). The seasonal cycle in the near-bed CHL-a concentration is determined by the spring bloom. The role of the wave climate as the primary forcing in the SPM seasonal cycle is discussed. The tidal current provides a background signal, generated predominantly by local resuspension and settling and a minor role is for advection in the cross-shore and the alongshore direction. We tested the logarithmic Rouse profile to the vertical profiles of both the SPM and the CHL-a data, with respectively 84% and only 2% success. The resulting large percentage of low Rouse numbers for the SPM profiles suggest a mixed suspension is dominant in the TMZ, i.e. surface SPM concentrations are in the same order of magnitude as near-bed concentrations. |
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