FIELD EXPERIMENT ON RHIZOPHORA PLANTING IN MUD FLAT AREA, KHUNG KRABAEN BAY

Abstract

In May 1992, seedlings of Rhizophora apiculata and R. mucronata were planted in mud flat area, Khung Krabaen Bay, Chantaburi (12 34' N, 101 65' E). The spacing of 0.5 x 0.5 m and 1 x 1 m were applied for both species. Soil properties, survival rates and growth performances of seedlings were investigated in August 12, 1995. It was found that the mud flat comprised 56.08% of soil particle with Size less than 212 µm. Average dissolved oxygen (DO), electrical conductivity (EC), NaCl, and pH of the soils at 5 cm depth were 0.69 mg/l, 0.42 s/m, 0.21%, and 8.07 respectively. The values slightly changed at 30 cm depth where average DO, EC, NaCl, and pH of the soils were 1.79 mg/l, 0.46 s/m, 0.24 %, and 8.25 respectively. Values of survival rate, diameter at 30 cm above ground (D_0.3 ) and total height (Ht) of R. mucronata in both spacing were remarkable greater than those of R. apiculata. In addition, survival rate and total height of R. apiculata in spacing 0.5 x 0.5 m were remarkable greater than that in spacing 1 x 1 m, whereas diameters at 30 cm above ground in both spacing showed no different. Growth of R. mucronata performed without any remarkable influencing from the spacing, but the narrower the spacing, the higher the survival rate was observed.