Influence of macrofauna

Field studies of leaf removal by sesarmide crabs in mangrove forests in Thailand have shown that the crabs can remove about 75% of the total daily litter fall and green, yellow as well as brown leaves were consumed (Fig. 1.12). It was estimated that the total population of sesarmide crabs could consume 58% of the total leaf litter per year, in this case 1130tons (Thongtham etal., 2003). A more detailed study of the economically important sesarmide crab 

Neoepisesarma versicolor was done, and it was found that the crab spends most of the time during the day in its burrow or resting by the entrance, and is mainly active during the night. It mainly feeds on mangrove leaves (62%) and scraped-off food materials from sediment surface (38%). The plant material mostly comprised small pieces of mangrove leaves. Supplementary laboratory studies of leaf consumption and leaf preferences on N. versicolor showed that the crab mostly feeds on brown leaf, followed by green and yellow leaves. 

Introduction of sesarmine crabs (Uca sp.) into non-bioturbated mangrove sediments has been found to enhance the sediment organic matter decomposition (Nielsen etal., 2003b). The sulphate reduction activity was in particular 

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