Geomorphology and sedimentology of mangroves and salt marshes: the formation of geobotanical units

LARA, RUBÉN JOSÉ; SZLAFSZTEIN, C.F.; COHEN, MARCELO; OXMANN, J.F.; SCHMITT, B.B.; SOUZA FILHO, P.W.

Coastal Wetlands: An Integrated Ecosystem Approach

Elsevier

Lugar: Amsterdam; Año: 2009; p. 593 - 615

<!-- /* Font Definitions */ @font-face {font-family:Times; panose-1:2 2 6 3 5 4 5 2 3 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:536902279 -2147483648 8 0 511 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-fareast-language:PT-BR;} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> The topic of the present chapter is treated under a multiscale approach involving the effect of the major factors leading to the development of salt marshes and mangroves, in a continuum of varying inundation frequency. At a global scale, this involves the main driving forces responsible for shaping sedimentary environments where mangrove and salt marshes can develop, such as the role of tectonics in the formation of extended tidal plains on passive continental margins. At a regional level, the interactions between hydrology and sediment dynamics are treated concerning the origin of geoforms and substrates adequate for the growth of mangroves and salt marshes. Further, the effect of sea level and climate on the regional formation and the sequential alternation in the respective dominance of each of these vegetation units is discussed. The local influence of inundation frequency on the biogeochemical properties of sediments in salt marshes and mangroves is treated focusing on the dynamics of limiting nutrients and the interactions between plant and substrate.