Comparative micromorphology of some soil types of Lower Egypt

Abstract

A comparative micromorphological study was carried out on typical profiles of six soil types that represent major soil regions of Lower Egypt. The macro- and micromorphology of each soil profile is described and the main physical and chemical data are given. The mode of occurrence and organization patterns of the fabric elements (plasma, skeleton grains, and voids) and units (s-matrix, pedological features, and peds) are systematically discussed at the different fabric levels (plasmic fabric, plasma-skeleton grains fabric and basic, elementary, primary, and secondary structure). It was found that most of the soil profiles were apedal. The main pedological features were sesquioxidic and/or carbonate nodules and gypsic crystallaria. The plasmic fabric, in general, was argillasepic but was vo-or skel-masepic in the clayey soil types. The plasma-skeleton grains fabric was mainly porphyroskelic. The basic structure included vughy and planar types, and the elementary and primary structures included glaebular, crystallaric and subcutanic types. Only the heavy clayey horizons showed secondary structures such as platy to subrounded blocky peds. Micromorphological features are discussed in relation to soil-forming processes.