The study on the effect of MPTS planting system on microclimate, physical and chemical soil properties in the catchment area of Tondano Lake, North Sulawesi [Indonesia]

The multi purposes trees species (MPTS) are the trees species which were recommended for widely developed by Government in ordered to granted the people needed who lived in around forest area. Some information are required to support this MPTS development programs. Aleurites moluccana is one tree species of MPTS which had known as a fast growth and aleurites oil producer was required study of it's effect to environment, land productivity and farmer income. In related to this issues the experiment was carried out in the catchment area of Tondano Lake, North Sulawesi during October, 1998 to March, 1999. The objective of the research was to determine the effect of plantation for microclimate fluctuation and changes in physical and chemical soil characteristics after the trees had been planted. Air temperature and relative humidity was observed periodically on the site plantation. Soil sampling was carried out at the three plantation systems (monoculture of aleurites, mixed plantation of aleurites and fruits trees and farming area without trees systems) with soil profile and boring. Composite samples of soil cores were taken in unit plots size 0.025 ha, at the top, middle and bottom slopes with three replications for every plantation system at depths of 0-15 and 15-30 cm. Soil analysis was taken at the soils laboratory of Hasanuddin University and samples of soil water content analysis which observed periodically was taken at the laboratory of Ujung Pandang Forestry Research Institute. Significant differences between characteristics of the three plantation systems sites were determined by "t" test. The result showed that monoculture of Aleurites plantation site habit the higher organic matter than the others, also Potassium and CEC in the all depth were significant. Phosphor was significant only at the depth of 0-15 cm. Soil acidity (pH) at all depth towards significance, the lower soil pH on aleurites site. Changes in soil physical characteristics were significant only at the bulk density, permeability and water content. Other physical and chemical characteristics indicated relatively the same results among the plantation systems. Average of air daily temperature (22.08 deg. C) under aleurites lower than the others plantation systems but the average of relative humidity (89.26 percent) higher than the others