Forty five soil samples were collected from the four pedons of the hill areas at Chittagong University based on the depth of soil horizon. Soil profiles on hill top were relatively well developed and belonged to Ultisols according to USDA soil Taxonomy. The profiles at the piedmont were relatively young soils and classified as Inceptisols and Entisols. The soils of all profiles were characterized by coarse texture (38% to 73%, sand fraction), high bulk density (1.15 to 1.32 Mg•m −3), low organic-C content (0.26% to 1.73%), acid soil reaction (2 H O pH varied from 4.44 to 5.52 and pH KCl from 3.57 to 4.90). Soils in all pedons were poor in exchangeable bases and base saturation. The CEC values ranged from 9.12 cmolc•kg −1 to 14.5 cmolc•kg −1 while ECEC varied from 1.96 to 4.78 cmolc•kg −1. The exchangeable Al (aluminum) concentration ranged from 0.41 to 0.66 cmolc•kg −1. Exchangeable acidity level ranged from 0.74 to 1.25 cmolc•kg −1. Exchangeable Al and aluminum saturation increased with depth and their concentrations were below the toxic range for tree stands. The study revealed that more young soils formed on the piedmont sites had somewhat better properties as compared to matured hill top soils. The variation in physico-chemical properties of the soils seemed to be influenced by the topography to a greater extent in the studied area.

Soil samples were collected from M. R. Khan tea-estate area of Moulvibazar district, Bangladesh. Organic matter, active acidity, reserve acidity, cation exchange capacity, clay content and textural class of the collected soil samples for different topographic positions and depths were determined. The percentage of sand, silt and clay varied from 59.75 to 70.50, 12.50 to 20.00 and 14.50 to 22.75, respectively. Active acidity and reserve acidity of the soils varied from 4.13 to 5.82 and 3.46 to 4.84, respectively. Organic matter content varied from 0.37% to 1.93%. Cation exchange capacity (CEC) varied from 11.42 to 24.86 cmolKg -1 . Soils were acidic in nature with considerably high reserve acidity. The measured parameters of the soil samples were plotted and analyzed with reference to topography and depth. The parameters have been found to vary with sampling sites, depths and topography.

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DTPA (Diethelene-triamine pentaacetic acid) extractable micronutrients of surface soil samples from six different locations of Cox's Bazar and Chittagong districts were studied. All the soils under study were sufficient in DTPA extractable Fe, Mn and Cu contents. The available Zn contents in soils of Dulhazara, Chengchhari and Faissakhali under study were also above the critical limit while soils at Fulchhari, Hasnabad and CU were deficient in available Zn. The study also showed that DTPA extractable Fe content had the significant and positive relationships with clay and soil organic carbon. On the hand, negative and significant relationship was observed between extractable Mn and soil pH while DTPA extractable Zn and Cu were positively and significantly correlated with soil organic carbon of the studied area.