Mangrove plantation. A total number of 1,723 Rhizophora saplings and 327 Avicennia marina saplings were planted in February 2006. Rhizophora saplings were planted in two rows along the lower edges of the bund whereas Avicennia saplings were planted about 2 meters above the Rhizophora plantation. Both Rhizophora and Avicennia were planted at 5 meters intervals in a row. Data on growth parameters of both Rhizophora and Avicennia were collected at three-month intervals and survival rate was observed once a month. At the end of a year, the survival rate of Rhizophora was about 70 per cent and that of Avicennia was 90 per cent. The average height of Rhizophora after one year was about 0.74 meters and the average number of leaves per plant was 36. The average height of Avicennia was only 0.21 meters. The reason for the low survival rate of Rhizophora was pest attack, which is not normally observed in wildlings. One species of sap-sucking scale insect of the Cicadae family was found affecting the leaves of the Rhizophora plants. This pest attack was noticed in 28 plants (1.6 per cent of the total population) and all of them died before control measures could be taken. It was observed that the attack by scale insect was severe when the 20 THE ASIA REGIONAL FORUM ON BIODIVERSITY salinity of the water in the farming system goes below 24 ppt. To prevent infestation, the plants were sprayed with different concentrations of neem oil, which showed that 5 per cent solution was very effective, when sprayed three times at an interval of 15 days. In March 2006, all the dead Rhizophora saplings were replaced with two-year-old nursery grown saplings. At the end of November 2009, all Rhizophora and Avicenna saplings were found surviving and Rhizophora reached an average height of 2.26 meters with about 46 stilt roots. Avicennia reached a height of about 1.69 meters with more than 60 aerial roots. Halophyte plantation. A succulent halophyte namely, Sesuvium portulucastrum, which has commercial potential as a component of salads, was planted on the top and sides of the bunds in January 2007. Stem cuttings of about 15 cm in length were planted at an interval of 1 meter. The fresh weight of the plantation, measured at monthly intervals, showed that values increased from 542 g/m2 in September 2007 to 1,132 g/m2 in January 2008 and about 1,344 g/m2 in April 2009. Observation indicates that the growth of this plant reaches its peak only during the northeast monsoon season. Figure 3. A view of the Integrated Mangrove Fishery Farming System showing the inner bunds, outer bunds, mangrove plantation, halophytes and water spread area - April 2007.
In Celebration of His Majesty the King of Thailand’s 84th Birthday Anniversary
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