Evaluation of Soil Suitability for Paddy Cultivation in Chhattisgarh – A Parametric Approach

Fourteen different soils from the government research farms mostly under paddy cultivation in seven districts of Chhattisgarh State were studied. Soils were evaluated for paddy by using parametric approach. The actual crop yields were correlated to identify and establish relationship among soil subgroups and yields of paddy. These soils varied in their climate: (Rainfall 1200–1500 mm; temp. (Max.), 35–45°C; (Min) 10–15°C, geology (granite, sandstone, laterite & alluvium), landforms (plain, plateau, & terrain valleys), slope gradient (1–3, and 8–15%), drainage (excessive, somewhat excessive, well, and moderately well). Similarly, there was considerable variation in different soils (min. to max.) pertaining to soil depth (7–150 cm), content of sand (14–16 to 65–73%), silt (8–10 to 25–35%), clay (18–15 to 60–65%), coarse fragments (8–10 to 40–45%), surface texture (loam to clay), pH (5.4–6.5 to 7.7–8.2), organic carbon (0.2–0.3 to 2.1–2.4%), CEC (8–12 to 40–44 cmol(p⁺)kg⁻¹), and base saturation (50–65 to 85–97%). These soils were classified as Haplusterts (Kanhar) (Typic/Chromic/Entic/Udic); Haplustepts (Matasi) (Lithic/Typic/Vertic/Udic); Haplustalfs (Typic/Udic), Typic Rhodustalfs, Plinthustalfs (Dorsa), Ustorthents (Bhata) (Lithic/Typic) are highly related to landform and geological make up. The soil suitability classes, based on cumulative rating value, for each soil, subgroup were assessed and correlated with actual crop yield. The yield efficiency is estimated which is highly correlated with actual yield of crop. The suitability classes along with rating values and yield as SI (Highly suitable) > 851, Udic Haplusterts (41.1 q ha⁻¹), Entic Haplusterts (37.8 q ha⁻¹), Chromic Haplusterts (37.7 q ha⁻¹), Typic Haplusterts (34.7 q ha⁻¹), Udic Haplustepts (31.1 q ha⁻¹); S2 (Moderately suitable), 701–850, Vertic Haplustepts (22.0 q ha⁻¹), Typic Haplustepts (20.0 q ha⁻¹); S3 (Marginally suitable), 551–700 Plinthustalfs (18.5 q ha⁻¹), Udic Haplustalfs (16.3 q ha⁻¹), Typic Haplustalfs (1l.5 q ha⁻¹), Typic Rhodustalfs (10.2 q ha⁻¹); Nl (Not suitable-temporarily) 401–550, Lithic Haplustepts (8.4 q ha⁻¹), Typic Ustorthents (6.9 q ha⁻¹), and N2 (Not suitable-Permanently) Lithic Ustorthents (5.0 q ha⁻¹). The rating values hold true with actual yield of paddy and potential yield efficiency per cent.