Paddy lands of south Telangana plateau (Rayalseema), Andhra Pradesh, India: A detailed suitability assessment

Abstract

Soil survey in detailed was undertaken at Rayachoty mandal of YSR Kadapa district, Andhra Pradesh on 1:10,000 scale by using base maps toposheet, sentinel-2 imagery and google imagery. Master soil profile samples were analysed in laboratory for physico-chemical properties. Based on morphological, physical and chemical properties, four major paddy growing soil series were established. As per the USDA keys to soil taxonomy, soils are classified into Madhavaram (Fine loamy mixed isohyperthermic Typic Haplustepts), Balreddigaripalli (Loamy-skeletal mixed isohyperthermic (calcareous) Typic Haplustepts), Nayanurpalli (Sandy mixed isohyperthermic Typic Ustorthents) and Duganvandlapalli (Fine Loamy mixed isohyperthermic (calcareous) Typic Haplustepts) series. Total paddy land in the mandal is 4745.33 ha (20.42%) out of which paddy is moderately suitable (S2) in 4.24% area and marginally suitable (S3) in 12.29% area and 3.87% area is currently not suitable (N). However, in the total geographical area (23240.70 ha) 63% area is marginally suitable provided with irrigation. Major limitations for paddy cultivation are of climate, topography, soil texture, drainage, rooting condition, gravelliness and soil fertility. Soil quality index (SQI) of paddy lands varied from 182 to 237 with the respective relative soil quality index (RSQI) of 45.50 to 59.25. The soil erodibility (K) factor ranged from 0.44 to 0.67 (t ha h MJ-1 ha-1 mm-1). Lower K factor in Balreddigaripalli series followed by Madhavaram series due to lower clay content and high sand content needs higher priority for erosion control. Hence, paddy can be cultivated in both uplands as well as in lowlands in the mandal with the application of external mineral nutrients along with organic manures with suitable agronomic management practices including soil and water conservation techniques.