Characteristics and classification of soils of Loktak Catchment Area of Manipur for sustainable land use planning

Typical pedons representing major landforms of Loktak catchment area of Manipur viz. very steep high hill slope, steep high hill slope, steep medium hill slope, moderately steep medium hill slope, moderately sloping foot hill slope and very gently sloping plain, developed from shale and occurring at different elevations under varying landuse were studied for their morphological and chemical characteristics and classified. Soils were deep, moderate to slightly acidic (pH 4.6–5.4) in the surface, rich in organic carbon, low to medium in exchange capacities with higher clay and low base status in the subsurface horizon. Soils were high in available nitrogen, medium to high in available potassium and low in available phosphorus. Available iron and manganese were high, Cu and Zn were low particularly in subsurface horizon. The BaCl2-TEA acidity was several times more than KCl acidity. Translocation of clay and iron oixde was prominent. High soil acidity associated with aluminium toxicity and gravelly substratum were the main limitations in these soils. Soils were classified as Humic Dystrudepts, Humic Hapludults, Typic Haplohumults, Typic Palehumults and Aquic Haplohumults. On the basis of the major soil constraints, suitable landuse plan has been suggested.