Diagnostics and soil forming characteristics of alluvial-meadow soils of Ganykh-Ayrichay valley, Azerbaijan

This study is devoted to the influence of ecological conditions on soil forming and improving the nomenclature of alluvial-meadow-forest soils in the flood plains of the subtropical forest-shrubby zone within Azerbaijan. On the basis of detailed soil mapping, the primary areal of soil units and the structure of soil cover were determined in the area of the Ganykh-Ayrichay valley. The spatial distribution of primary soil units, genetic features and diagnostic indexes (extend of bedding and development of the soil profile, thickness of the decomposed- accumulative layer, content of humus, total nitrogen, base saturation, particle size distribution, etc.) of stratified and typical suborders of alluvial-meadow-forest soils are identified. The turbidity and content of the weighted deposits of stream water is determined using regime-measurements. The weighted deposits contain a considerable amount of humus (1.2-1.8%) and its water soluble part, total nitrogen (0.09-0.13%) which significantly affects the morphogenetic diagnostics of the above described soils. The status of the humus content is characterized by a high activity, in which humic acid (15.3-20.8%) and fulvic acid (16.2-22.5%) dominate significantly, while the third fraction riches to 1.23-2.30% in the selective-group content. The ratio of Ch.a.:Cf.a. reaches to 0.88-0.93 in the leached soil profile (5.8-6.0), while reaching to 1.19-1.32 in carbonated soils (7.3-7.5). The total chemical composition of soils shows that the profile of leached soil is characterized by increasing the SiO2 (60.2-64.0%) content and sesquioxides (Al2O3=17.6-19.5%, Fe2O3=8.5-10.3%) and the carbonated suborders contain more CaO (7.1-9.2%). The active form of iron (Fe3+=182-496; Fe2+=56-123 mg 100 g soil) hints the insufficiency content in carbonated soils.