Logo image
The Contrasting Ecology of Temperate Macrotidal and Microtidal Estuaries
Book chapter   Open access

The Contrasting Ecology of Temperate Macrotidal and Microtidal Estuaries

J.R. Tweedley, R.M. Warwick and I.C. Potter
Oceanography and Marine Biology: An Annual Review, pp.73-171
CRC Press
2016
pdf
Tweedley.OMBAR.pdfDownloadView
Author’s Version Open Access

Abstract

Tidal range is a master factor governing the differences in physico-chemical and biological characteristics between microtidal (<2 m) and macrotidal (>2 m) estuaries, which, for convenience, thus include mesotidal estuaries (2–4 m). Microtidal estuaries differ from macrotidal estuaries in geomorphology, tidal water movements, salinity regimes, residence times, turbidity, sedimentology and intertidal area. Consequently, their phytoplankton, microphytobenthos and macrophytes communities differ in biomass and production, areal extent, distribution patterns and composition. Mesozooplankton comprise predominantly autochthonous species in microtidal estuaries and allochthonous species in macrotidal estuaries. Meiobenthos in microtidal estuaries have greater densities in subtidal than intertidal areas and species persist along the estuary. Macrobenthos is dominated by small deposit-feeding species in microtidal estuaries, whereas macrotidal estuaries contain some larger species and suspension feeders. Species richness and abundance of estuarine-resident fish species and the contributions of diving piscivorous birds and wading invertebrate-feeding birds are greater in microtidal estuaries. As paradigms regarding estuarine ecology have been based mainly on northern hemisphere macrotidal systems, this review has redressed this imbalance by detailing the extent of differences between microtidal and macrotidal estuaries. In particular, it uses data and case studies for southern hemisphere microtidal systems to demonstrate that the physico-chemical characteristics and ecology of the main flora and fauna of microtidal estuaries are frequently not consistent with those paradigms.

Details

Metrics

709 File views/ downloads
357 Record Views
Logo image