การประเมินศักยภาพของที่ดินในพื้นที่ศูนย์การศึกษามหาวิทยาลัยเชียงใหม่ “หริภุญไชย” อำเภอเมือง จังหวัดลำพูน

Abstract

A study on land potential evaluation in Chiang Mai University Education Centre “Hariphunchai”, Mueang district, Lamphun province was done, Eight pedon. The aim of this study was to investigate soil morphology in the field. Then, the soil samples were analyzed for physical, chemical and mineralogical properties in laboratory according to standard methods. Moreover, the plant species diversity was also assessed. The results showed that soils in Chiang Mai University Education Centre “Hariphunchai”, Mueang district, Lamphun province of pedon 1, 2, 5, 6, 7 and 8 were the soil in dry dipterocarp forest, while pedon 3 and 4 is the soil in mixed deciduous forest, where the elevation was 357-517 meters above mean sea level. These areas were undulating to very steep slope area. Most of the pedon were residuum from shale and sandstone, except pedon 5, 6 and 7 were residuum from sandstone. Soil morphology in the field showed that the soil profile of pedon 1 and 2 were A-BA-Bt-BC-Cr-C-R which classification of soil order was Ultisols, subgroup was pedon 1: Typic Paleustults, pedon 2: Typic Haplustults. The soil profile of pedon 3 and 4 were A-BA-Bt-BC-C-R which classification of soil order was Alfisols, subgroup of pedon 3 was Ultic Paleustalfs, pedon 4: Ultic Haplusalfs. The soil profile of pedon 5 and 6 were A-Bw-C-R which soil order were classified as Inceptisols, and subgroup were pedon 5: Typic Dystrustepts, pedon 6: Typic Haplustepts. The soil profile of pedon 7 and 8 were A-CA-Cr-C-R which classification of soil order was Entisols, subgroup was pedon 7: Lithic Ustorthents and pedon 8: Typic Ustorthents. The topsoil was black to dark reddish brown, while subsoil was yellowish brown to dark reddish brown. Soil structure of all pedon in topsoil and sub soil were subangular and angular blocky. Physical properties showed that the soil texture in topsoil and subsoil were sandy loam to clay. Most gravel content tends to increase with depth, except pedon 1 tends to decrease with depth. In all pedon, bulk density in topsoil was lower than subsoil. Particle density and total porosity of all pedon were varied across of soil profile. Field capacity, permanent wilting point and available water capacity in Ultisols and Alfisols increased with depth, but the values decreased from topsoil to subsoil of Inceptisols. Chemical properties showed that, the reaction of soil: water ratio (1:1), in topsoil was strongly acid to neutral; subsoil was very strongly acid to moderately acid. Soil reaction to: potassium chloride ratio (1:1) in topsoil was extremely acid to slightly acid, while subsoil was ultra acid to slightly acid. Organic matter content, total nitrogen, available phosphorus and extractable calcium of topsoil were higher than subsoil. Available potassium and extractable potassium in of most topsoil were higher than subsoil, except pedon 1 which the properties in topsoil were lower than subsoil. The value of extractable magnesium and extractable sodium were fluctuated across of soil profile. sum extractable bases of most topsoil were higher than subsoil, except pedon 6 which topsoil was lower than subsoil. Most extractable acidity of topsoil was similar to subsoil, except Ultisols order showed higher value than the other orders. Cation exchange capacity of topsoil and subsoil ranged from low to high worth. Most bases saturation of topsoil was higher than subsoil, except pedon 6 which the topsoil was lower than subsoil. For soil fertility evaluation, Alfisols order showed more fertility than the other, except topsoil of pedon 7. For mineralogical properties, the result found that. The mineralogical class of most of all pedon was classified as Mixed which consisted of kaolinite, illite, and montmorillonite. Pedon 4 was classified as Kaolinitic because one of kaolinite was found. The potential of soil unsuited for paddy rice cultivation. Moreover, the soil was poorly suited to unsuited for pasture, corn, longan, rubber and oil palm due to the limitation of topography and stoniness. For plant species diversity, the study showed that plot 1, 2, 5, 6, 7 and 8 were dry dipterocarp forest, while plot 3 and 4 were mixed deciduous forest.