Degradation of mangrove tissues and implications for peat formation in Belizean island forests
Article first published online: 26 MAR 2002
Journal of Ecology
Volume 89, Issue 5, pages 818–828, October 2001
How to Cite
Middleton, B. A. and McKee, K. L. (2001), Degradation of mangrove tissues and implications for peat formation in Belizean island forests. Journal of Ecology, 89: 818–828. doi: 10.1046/j.0022-0477.2001.00602.x
- Issue published online: 26 MAR 2002
- Article first published online: 26 MAR 2002
- leaf burying crabs;
- litter decomposition;
- litter processing;
- peat accumulation
- 1Macrofaunal leaf consumption and degradation of leaves, woody twigs and roots were studied in mangrove island forests on a Belizean island. Factors influencing accumulation of organic matter deposited both above and below ground in this oligotrophic, autochothonous system were assessed.
- 2Leaf degradation rates of Rhizophora mangle (red mangrove), Avicennia germinans (black mangrove) and Laguncularia racemosa (white mangrove) measured in mesh bags, were much faster in the lower than the upper intertidal zone. Mass loss was most rapid in A. germinans but zonal effects were much larger than species differences.
- 3Exposure to invertebrates such as crabs and amphipods tripled overall rates of leaf litter breakdown. In the lower intertidal, crabs completely consumed some unbagged leaves within 23 days. Crabs also had an effect on some upper intertidal sites, where degradation of leaves placed in artificial burrows was 2.4 times faster than when placed on the soil surface.
- 4In contrast to leaves (27 ± 5% remaining after 230 days), roots and woody twigs were highly refractory (40 ± 2% and 51 ± 6% remaining after 584 and 540 days, respectively). Root degradation did not vary by soil depth, zone or species. Twigs of R. mangle and A. germinans degraded faster on the ground than in the canopy, whereas those of L. racemosa were highly resistant to decay regardless of position.
- 5Peat formation at Twin Cays has occurred primarily through deposition and slow turnover of mangrove roots, rather than above-ground tissues that are either less abundant (woody twigs) or more readily removed (leaves).