Soil resource characterization, land capability and suitability of soils in hilly undulating terrain - a case study.
Amaresh Das, Shinde R. D.
Author Affiliation: Department of Soil Science, Navsari Agricultural University, Navsari, India.
International Journal of Agricultural Science and Research (IJASR) 4 : 171-183
Abstract : An investigation was carried out on soils of Sarvar village situated at latitude and longitude of 20°50?55?N and 73°36?55?E, respectively (an elevation of 350 to 458 m above msl.) in undulating hilly sloppy land of Dang district of Gujarat (India) with an objective to characterize soil resource, classify these soils as per land capability and also to evaluate their suitability for crops. The village comes under heavy rainfall zone with an average annual rainfall of around 2500 mm. Seven pedons were dugout at varying elevation in the village and studied and samples were collected from each pedon. Samples were analyzed for important physical, Physico-chemical and chemical characters. Based on the analytical data and limitations, soils were classified as per USDA soil class, Land capability class and based on the optimum growth requirement of crop in relation to climate, soil-site parameters, the suitability of soils for prevailing crops were evaluated, keeping in mind the ecological stability of the area. Results revealed that texture of surface soils varied from gravelly loam or gravelly clay loam, while slope varied from 0-1% (nearly flat land) to 25-35% (steep sloping land). The depth of different pedons varied widely i.e. from 7.5 (very very shallow) to >90 cm (deep). The erosion varying widely ranged from e1 (slight/sheet erosion) to e4 (very severe/ big gully). Pedon 1, 2, 3, 4, 5, 6 and 7 were classified as Fluventic Ustochrep, Vitrandic Ustochrept, Lithic Eutrochrept, Fluventic Ustochrept, Lithic Ustochrept, Udic Ustochrept and Lithic Ustorthent respectively. Pedon 1 and 6 were classified under land capability sub-class IIes to IIesw, while pedon 2, 3, 4, 5 and 7 came under IIIs, Ves, IIIes, VIes and VIIes sub-classes, respectively. Considering the extent and type of limitations, sub classes were further classified in to different capability units. Very gently sloping flat (2%) land and very gently sloping flat hill top (2 to 3%) coming under IIes and IIesw sub-class were marginally suitable for (S3) rainfed rice, finger millet and vari, and moderately suitable (S2), particularly during kharif rainy season, for sorghum, pigeon pea and groundnut, vegetables like, cabbage, tomato, french bean, peas and cowpea and horticultural plants like, mango, custard apple, guava and cashew nut. Very gently sloping (4 to 5%) land coming under IIIs sub-class were placed under marginally suitable (S3) for all the above crops with proper land conservation measures during Kharif and moderately suitable (S2) for all horticultural plants as above. Undulating moderately sloping terrace (5 to 8%) land coming under IIIes sub-class could be placed as non-suitable (N1) to marginally suitable (S3) after proper management for all the crops as above, excepting horticultural plants as above which were moderately suitable (S2). Undulating moderately sloping (9 to 10%) land coming under Ves sub-class was considered non-suitable (N1) for all arable crops and marginally suitable (S3) for all horticultural plants as above. Moderately to strongly sloping (14 to 16%) and strongly sloping hill cap (19 to 20%) land coming under VIes and VIIes sub-classes were non-suitable (N1) for arable crops and should be grouped for development of forest and pasture land with Teak, Subabul, Nilgiri, Khair, Kalam, Karanj, etc. for income generation and ecological stabilization as well.