Aboveground litter production, accumulation, decomposition, and tidal transportation of coral reef-type mangrove forest on Pohnpei Island, Federated States of Micronesia

• ONO Kenji

  Forestry and Forest Products Research Institute

• FUJIMOTO Kiyoshi

  Faculty of Policy Studies, Nanzan University

• HIRAIDE Masakazu

  Forestry and Forest Products Research Institute

• LIHPAI Saimon

  Department of Land and Natural Resources, Pohnpei State Government

• TABUCHI Ryuichi

  Tama Forest Science Garden, Forestry and Forest Products Research Institute

Abstract

Litter production, accumulation, and decomposition were examined on the seaward and landward sides of a long-term mangrove research site on Pohnpei Island, the Federated States of Micronesia, to estimate the contribution of litter deposited on the mangrove forest floor to carbon accumulation in mangrove forests. The annual litter production in the forest site was relatively high, 15 Mg ha^-1 yr^-1. The litterfall was composed of leaves (55%), reproductive organs such as flowers and seeds (34%), and bark and small branches (11%). The seasonal fluctuation of the litter was small. The amounts of litter deposited on the floor were 0.51 Mg ha^-1 on the seaward side and 0.76 Mg ha^-1 on the landward side. Compared with the mangrove substratum, the litter deposited on the forest floor has an extremely low capacity to act as a carbon sink. During the first year of the leaf decomposition, the mangrove leaves decomposed markedly (k = 7.0 - 18.2) faster than the leaves of the terrestrial mahogany forest (k = 0.3). The mangrove leaves decomposed rapidly, losing more than 60% of their initial weight in the first month. This high rate might result from leaching of labile fraction from the leaves by the high frequency of immersion as well as by the high levels of activity of decomposers on the forest floor at high temperatures and humidity. Moreover, the effect of crab’s feeding on the litter disappearance could not be disregarded. Tidal litter transportation rate was examined by collection of marked leaves along a tide level gradient. The transportation rate was greater as the highest tide level was higher. This study clarified that the disappearance of litter on the mangrove forest floor was strongly influenced by the tide, especially on the seaward side, as well as by the active microbial and faunal decomposability. We concluded that, despite the mangrove forest’s high litter production, litter on the forest floor did not contribute much to carbon accumulation, especially on the seaward side, since litter was disappeared rapidly from forest floor by tidal exportation and strong microbial activity.

Journal

• Tropics

  Tropics 15 (1), 75-84, 2006

  JAPAN SOCIETY OF TROPICAL ECOLOGY

Keywords

• mangrove forest
• forest floor dynamics
• litterfall
• deposited litter
• leaf decomposition
• Micronesia

Details

• CRID: 1390001204423902592
• NII Article ID: 10019294186
• NII Book ID: AN10528811
• DOI: 10.3759/tropics.15.75
• ISSN: 18825729
• ISSN: 0917415X
• NDL BIB ID: 8077026
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I8077026
• Web Site: http://www.jstage.jst.go.jp/article/tropics/15/1/15_1_75/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed