EVALUATION OF NEWLY ESTABLISH RICE FIELD IN LUBUK LINGGAU, SOUTH SUMATRA

Newly establish rice fields outside from Java Island sometime facing on low nutrient content. To evaluate problem on low nutrient, one year old establish open rice fields converting from dry land in Lubuk Linggau, South Sumatra was investigated both in the field and in the laboratory. Three soil profiles have been made in the field based on the toposequence (HP32, HP33, HP34), one profile in the original upland area (HP31), and two profiles (HP30, HP35) were made randomly. To evaluate soil properties, 31 soil samples were analyzed in the laboratory for their mineral composition, physical and chemical properties. Results indicate that mineralogical composition of sand fraction is dominated by quartz and opaque, while clay mineral is dominated by kaolinite. Soil nutrient resource is poor. Organic carbon content range from low to very low, iron concentration range from moderate to high, aluminum saturation range from high to very high and phosphate in the form potential and available are low. The soils were classified as Typic Hapludox, Typic Kandiudults and Typic Endoaquents. Opening new rice fields in the slopping area through soil leveling cause the lost of soil horizon with organic carbon content and some layers with high aluminum saturation and high phosphate retention becoming exposed. In this area the limiting factors are low nutrient status, high status of aluminum and iron, and soils lack of phosphate