The habit of eating three kinds of mangrove leaves, nutrient content in mangroves leaves and feces of Sesarma sp. in Ca Mau province

Abstract

The study on feeding habit of Sesarma sp. in Vien An commune, Ngoc Hien district, Ca Mau province have shown that: for mangrove leaves, Sesarma sp. eats more yellow leaves than green leaves; for Avicenia alba leaves, Sesarma sp. eats no choice about yellow leaves and green leaves and for Bruguiera sp., Sesarma sp. eats more yellow leaves than green leaves. The experimental results about the choice between three types of leaves of Sesarma sp. have shown that: for yellow leaves, Sesarma sp. likes Avicenia alba leaves most, followed by Bruguiera sp. leaves and Rhizophora sp. leaves; for green leaves, Sesarma sp. likes green Avicenia alba leaves most and has no choice about Bruguiera sp. and Rhizophora sp. leaves. The nutrient content (C, N, P) in yellow leaves is lower than that in green leaves. When food goes through the digestive system, nutrition (C/N) has been significantly reduced. As for yellow leaves, the C/N ratio in Bruguiera sp. has been decreased 3.96 times from 94.49 in feces to 23.88 in leaf, and this ratio in yellow Avicenia alba leaf has been reduced 3.43 times from 68.33 (feces) to 19.94 (leaf). The ratios in Bruguiera sp. and Avicenia alba green leaves has been reduced 2.49 times and 1.5 times respectively. The nutrient content goes to the digestive system of Sesarma sp. has significantly increased which shows that Sesarma sp. is very important in nutrient cycle of mangrove forest and is one of the important links in the nutrient network of mangrove forest.