Some Morphology of Forest Soils in Two Community Forests, Mae Wang District, Chiang Mai Province

บทคัดย่อ

Some morphology of forest soils in HKL and HT community forests, Mae Wang, Chiang Mai province was studied. Three soil pits (1.5×2×2 m) were dug in each community forest. Soil samples were collected along soil profiles for analysis of physical and chemical properties and forest soil morphology. The results showed that (for 2 m soil depth) in HKL, soil bulk density was very low to medium; soil reaction (pH) was very strong to slightly acidic, organic matter was moderately low to very high, total N was very low to medium, available P was very low to moderately high, extractable K was very high, extractable Ca and Na were very low, extractable Mg was very low to low, the CEC was very low to high and% BS was very low to low. For HT, soil bulk density was very low to moderately low, soil pH was very strong to slightly acidic, organic matter was very low to moderately high, total N was very low to very high, available P was very low to moderately high, extractable K and Ca were very low to very high, extractable Mg was very low to medium, extractable Na was very low, the CEC was low to very high and % BS was very low. Soil development in both forests was classified in the order Ultisols, suborder Humults, great group Palehumults and the soil profiles were developed as A-AB/BA-Bt-Bt, and the parent rock was granite. Soil color in HKL was gray, reddish yellow, yellow red in dry form and gray, black, yellowish red in moist form. Soil texture was sandy loam and sandy clay loam, with granular and blocky structures, tubular pores and many fine and common medium roots in the topsoil with none found in subsoils. For HT, the soil color was gray, red, reddish yellow in dry form and dark gray, black, yellowish red, dark red in moist form, soil texture was sandy clay loam, sandy clay, clay loam and clay, with granular and blocky structures, tubular and irregular pores and many fine and common medium roots in the topsoil with none found in subsoils. The characteristics and morphology of the soils in both forests showed similar tendencies.