Tritep Vichkovitten

DOI: 10.14456/sjst-psu.2021.182

pp. 1392 - 1399

Abstract

Forest structure of Tagal mangrove (Ceriops tagal (Perr.) C.B. Rob.) and soil characteristics were examined at five
different positions along the 1,800 m transect line perpendicular to the coast of Trat province, Thailand. Tree stands at the
outermost station were highest and exhibited the decreasing trend from the coastal fringe landward. Average soil salinities were
ranging from 22 to 37 ppt and increased with increasing distance from coastal to the inner zone. High organic matter contents (up
to 44%) in soil from the inner stations indicated the peat formation in this mangrove landscape. Porewater nutrient concentrations
including nitrite+nitrate, ammonia and phosphate at the inner zones were relatively low compared to other mangrove forests.
Porewater sulfide was low and could not showed any negative effects on this mangrove vegetation. Responses of C. tagal to soil
salinity gradient under field conditions were evaluated in term of chlorophyll a (chl-a), chlorophyll b (chl-b), carotenoids, sugar
and starch. High salinity had no significant detrimental effects on photosynthetic pigments for both tree and seedling however,
variation on plant responses pattern was achieved. This study indicated the physiological adaptation of C. tagal to survive an
extensive variation of soil salinity could be varied depending on plant developmental stage.