A mathematical model for the vertical distribution of chlorophyll A in estuarine intertidal sediments
Brotas, V.; Serodiô, J. (1995). A mathematical model for the vertical distribution of chlorophyll A in estuarine intertidal sediments. Neth. J. Aquat. Ecol. 29(3-4): 315-321. https://dx.doi.org/10.1007/BF02084230 In: Netherlands Journal of Aquatic Ecology. Kluwer Academic Publishers/Netherlands Society of Aquatic Ecology: Bilthoven. ISSN 1380-8427; e-ISSN 2214-7098, more Also appears in:Moreira, M.H.; Quintino, V.M.S.; Rodrigues, A.M.J. (Ed.) (1995). Northern and Southern Estuaries and Coastal Areas: Proceedings of the ECSA-24 Symposium September 5-9 1994, University of Aveiro, Portugal. Netherlands Journal of Aquatic Ecology, 29(3-4). Netherlands Society of Aquatic Ecology: Bilthoven. 199-471 pp., more |  |
| Keywords | Marine/Coastal; Brackish water | | Author keywords | Chlorophylla vertical distributionmicrophytobenthosintertidal sediments |
| Abstract | Coastal and estuarine intertidal sediments are commonly colonized by dense populations of microphytobenthos. Due to wind and tides, important fractions of microphytobenthic populations may be buried. A mathematical model describing the depth variation of chlorophyll a in intertidal sediments was developed and experimentally tested. The model assumed first-order chlorophylla degradation and a constant mean burial velocity which resulted in a negative exponential variationCZ=COexp{-k/vz} (CZ andCO=chlorophylla concentration at depth zand at the surface;k=specific degradation rate of chlorophyll a to pheopigments;V=mean burial velocity). Chlorophylla concentration depth profiles in different sediment types measured at the Tagus estuary and Ria Formosa (Portugal) were used to validate the model. The model was adjusted to field data. The chlorophyll a degradation rate was measured in a microcosm experiment under total darkness and no tidal action, and sampled during three months. This rate was shown to be independent of time and depth for the upper 0–15 mm depth interval. This result allowed the estimation ofV for each sampling site. Comparison of predicted and observed temporal data further confirmed the validity of the model andk andV values. Despite its simplicity, the proposed model adequately described the depth distribution of chlorophylla in different types of intertidal sediments. The model allowed the quantitative characterization of the buried microphytobenthic biomass (depth-integrated biomass) and the assessment of its importance as potentially productive stock of cells. |
|
