Mireille Consalvey PhD Thesis - University of St Andrews

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Temporal changes in the microscale distribution of pigments can be used
to infer changes in biomass associated with migration (Paterson et al. 1998).
However, LTSEM and pigment sampling is destructive. Non-destructivc remote
sensing (RS) techniques use the optical properties of the sediments to make
inferences about the distribution/abundance of benthic autotrophs (Paterson et al.
1998). However, RS still requires considerable ground truthing.
1.6.2. Algae got rhythm?: Description of migratory work to date
Palmer and Round (1965) and Round and Palmer (1966) provided some
of the first detailed descriptions of the vertical migratory rhythms of
microphytobenthos which can be surnmarised:
1) Cells move to the sediment surface during the daylight hours when the
sediment surface is exposed by the tides.
2) Prior to submersion cells migrate away from the surface (also Faur6-Fremiet
1951; Happey-Wood and Jones 1988; Ser6dio et al. 1997; Paterson et al.
1998).
3) Individual species come to the surface at different times and may arrive in a
distinct order (also Paterson 1986) and stay for differing times.
4) Species may appear at the sediment for only a short period before leaving but
may return, hence showing a bimodal presence at the surface
5) There can be a difference in the migratory patters observed at low tide in the
moming, to low tide in the aftemoon
6) Migratory rhythms can be maintained in the absence of environmental cues
7) Migratory rhythms can be reset/rephased.
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