Differential rates of vertical accretion and elevation change among aerial root types in Micronesian mangrove forests

K. W. Krauss, J. A. Allen, D. R. Cahoon

Research output: Contribution to journalArticlepeer-review

214 Scopus citations

Abstract

Root systems in mangrove swamps have captured the attention of scientists for decades. Among the postulated roles of root structures include a contribution to the geomorphological stability of mangrove soils through sediment trapping and binding. In this study, we used feldspar marker horizons and sediment pins to investigate the influence of three different functional root types - prop roots in Rhizophora spp., root knees in Bruguiera gymnorrhiza, and pneumatophores in Sonneratia alba - on vertical accretion and elevation change in three mangrove forests in the Federated States of Micronesia. Prop roots facilitated vertical accretion (11.0 mm year-1) more than pneumatophores or bare soil controls (mean, 8.3 mm year-1). Sediment elevation, on the other hand, increased at an average rate of only 1.3 mm year-1 across all root types, with rate differences by root type, ranging from -0.2 to 3.4 mm year-1, being detected within river basins. This investigation demonstrates that prop roots can assist in the settling of suspended sediments from estuarine waters, yet prop root structures are not as successful as pneumatophores in maintaining sediment elevation over 2.5 years. As root densities increase over time, an increase in turbulence-induced erosion and in shallow subsidence as organic peat layers form is expected in Micronesian mangrove forests.

Original languageEnglish (US)
Pages (from-to)251-259
Number of pages9
JournalEstuarine, Coastal and Shelf Science
Volume56
Issue number2
DOIs
StatePublished - Feb 1 2003

Keywords

  • Accretion
  • Mangrove swamps
  • Micronesia
  • Pacific islands
  • Sedimentation

ASJC Scopus subject areas

  • Oceanography
  • Aquatic Science

Fingerprint

Dive into the research topics of 'Differential rates of vertical accretion and elevation change among aerial root types in Micronesian mangrove forests'. Together they form a unique fingerprint.

Cite this