Improvement and Development of Tin Mined Land for Forage Production

Abstract

Trial of 4 glass species with different rates of fertilization on spoiled tin mined land at Takua Pa, Phangnga province, was carried out during 1987-1988. For the silty – clay area, the average biomass of 4 grass species under different rates of fertilization was 6.05 ton/ha which was 13 times more than that of the control plots (0.45 ton/ha ). Brachiaria ruziziensis produced the highest biomass of 7.06 ton/ha. The biomass of the other grass species, Panicum maximum cv. hamil, Panicum maximum and Brachiaria brizantha were 6.86, 5.65 and 4.61 ton/ha, respectively. Statistical analysis of the biomass showed that there was significant difference ( p < 0.01 ) existed among grass species as well as among rates of fertilization. Apparently, the rate of fertilization of 400 kg/rai of chemical fertilizer ( 15 – 15 - 15 ) applied to this area seems to be more suitable than the other rates of application. For the sandy area, under the application of 400 kg/rai of chemical fertilizer and 4000 kg/rai of city compost, the average biomass of the 3 grass species was 0.86 ton/ha. There was a significant difference (p < 0.05 ) existed among grass species. Brachiaria ruziziensis gave the highest biomass of 1.07 ton/ha followed by Panicum maximum ( 0.78 ton/ha ) and Panicum naximum cv. hamil ( 0.74 ton/ha ) the results indicated that the average amount of biomass in the silty – clay area was 6 times higher than that in the sandy area. It was concluded that the application of fertilizer was the only feasible alternative for revegetation in the spoiled tin – mined area. The performance of those grass species were quite well if applied with fertilizer. The appropriate rate of fertilization was 400 kg/rai of chemical fertilizer.