Assessing the soil environment under major cropping systems in Kuanria canal command.

Abstract

Soil parameters viz. activities of soil enzymes, dehydrogenase, phosphatase and urease, soil organic carbon (SOC) content, SOC storage in the surface layer and in the profile were assessed in six different sites under three major cropping systems like rice-fallow, rice-sugarcane and rice-moong in the Kuanria command area of Odisha, India. The study reveals that the soil enzyme, dehydrogenase for surface soil (0-15 cm) for different cropping systems showed a range of 283.52 to 313.31 μg TPF g-1soil 24h-1 with the coefficient of variation (CV) ranged from 8.36 to 9.22%. Soil phosphatase activity ranged from 280.58 to 480.28 μg phenol g-1soil h-1 with the CV of 9.24 to 11.93% and soil urease activity ranged from 38.36 to 67.75 μg NH4 +- N g-1soil 2h-1 with CV of 9.73 to 11.08% irrespective of different sites and cropping systems. The SOC content varied from 0.34 to 0.95%, and there was no sharp difference of SOC due to difference in cropping systems for every soil depths. In the surface soil (0-15 cm), SOC storage was higher in rice-sugarcane crop rotation systems (18.90-20.53 Mg ha-1). However, other systems also had the organic carbon storage of 14.68 to 16.16 Mg ha-1 in rice-fallow and rice-moong. The SOC storage in the profile (0-90 cm) was the highest in rice-sugarcane rotation (100.43 Mg ha-1) and the lowest in rice-fallow (67.51 Mg ha-1) system, indicating a good soil environment with respect to SOC storage. This study concludes with the information on soil enzymes and SOC storage and carbon sequestration potential. These would be useful as inputs for many models studying soil environment and climate change.