Abstract
In order to clarify the vegetation and soil characteristics in the dry dipterocarp forest (DDF) and mixed deciduous forest (MDF) at Mae Chaem district, Chiang Mai, Thailand, fifteen quadrats (40×40m) were set up in each forest type. In DDF, 30 families, 56 tree species were identified, and the relative dominance of DIPTEROCARPACEAE was 75%. In MDF, 28 families, 77 tree species were identified and the relative dominance of LEGMINOSAE was 41%, VERVENACEAE was 18%. Though absence in DDF, bamboos was 26m^2 per hectare for stem basal area in MDF. The value of tree density in DDF was higher than that in MDF, however, the value of total basal area in DDF was lower than that in MDF. DDF was more simple stand structure as compared with MDF. Nutrient contents significantly differed in the upper soil layer among the soil profiles. DDF had lower contents of soil nutrients than MDF. In DDF, there were no differences in soil chemical properties among the three sites as upper, middle and lower on the slope. On the other hand, the pH, available P, total C content, total N content and exchangeable Ca content of the lower site at MDF was significantly higher than those of the other two sites.
