Effect of long term terrace cultivation on nutrient availability and lime requirements in acid soils of Kalimpong hills under mulberry farming

Abstract

This study was undertaken in 2011–12 to assess the effect of long term terrace cultivation on nutrient availability and lime (CaCO3) requirements in acid soils of Kalimpong hills under mulberry farming. Soil samples were collected from the mulberry field of Regional Sericultural Research Station (RSRS) farm, Regional Sericultural Research Station Annexure (RSRSA) farm and farmers field from eight different villages. The overall pH mean in the soils of RSRS farm and farmers field was 6.0 and 5.0 in RSRSA farm. The overall mean of OC content in the RSRS farm was 1.80% followed by 1.50% in farmers’ field and 1.30% in the RSRSA farm. The available nutrients e.g. nitrogen (N) 474.1 kg ha−1; phosphorus (P) 14.4 kg ha−1; potassium (K) 164.7 kg ha−1 and sulphur (S) 9.6 kg ha−1 were present in the soils of RSRSA research farm, however, these nutrients were 586.4 kg ha−1 (N); 17.9 kg ha−1(P); 183.6 kg ha−1(K) and 15.3 kg ha−1 (S) in the soils of RSRS research farm and 590.5 kg ha−1(N); 19.5 kg ha−1(P); 284.6 kg ha−1 (K) and 12.7 kg ha−1 (S) in the progressive farmers’ field. The overall mean of the CaCO3 requirements for reclamation of RSRSA farm soil was 2.30 mt ha−1 followed by 1.50 mt ha−1 in RSRS farm and 1.16 mt ha−1 in the farmers’ fields. These data revealed that, the long term terrace cultivation under mulberry farming in acid soils of entire Kalimpong hills, significantly affects the nutrients availability and lime requirements. The nutrients availability at RSRS research farm and farmers’ field under long term terrace cultivation was quite high than RSRSA research farm.