Morphological, Physical and Chemical Characteristics of Hill Forest Soils at Chittagong University, Bangladesh

Md Akhtaruzzaman,Md Enamul Haque,Khan Towhid Osman

doi:10.4236/ojss.2014.41004

Abstract

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 ( varied from 4.44 to 5.52 and pHKCl 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.

Highlights

IntroductionThe investigation area comprising of low hill soils is mainly underlain by little consolidated sandstone and shale of Dupi Tila formation probably of mid Miocene to Pliocene age [5]
The differences in soil characteristics associated with landscape position are usually attributed to differences in the runoff, erosion and deposition processes which affect soil genesis [1,2,3,4]
The results of this study showed that matured soils were developed on the hill top while more young soils formed on the piedmont sites

Summary

Introduction

The investigation area comprising of low hill soils is mainly underlain by little consolidated sandstone and shale of Dupi Tila formation probably of mid Miocene to Pliocene age [5]. These are well-drained strong brown, strongly structured, deep acid soils and low to moderately fertile. These soils unless hindered by lateritic formation, plinthitic concretions at shallow depth, are suitable for a wide range of forest tree species, horticultural species, and industrial plantations e.g. rubber, tea, systematic orchards etc. The degree of surface runoff and soil erosion is mainly related to land physiography and slope gradients

Objectives

Methods

Conclusion