Carbon Management in Irrigated Arable Lands of India

摘要

Carbon management which is to examine the options and mechanisms for mitigating the impacts of climate change is of utmost importance. This is very relevant in Indian agriculture as soil organic carbon (SOC) content has decreased by more than 50% in the past 70 years. Despite many studies highlight impacts of management practices on carbon (C) sequestration rates, a comprehensive review is lacking on different options for SOC management and their impacts in Indian arable soils. Hence, this review proposes conservation tillage and conservation agriculture (CA), inclusion of a legume in a cereal-cereal system, location specific organic farming (for basmati rice production), suitable agroforestry and integrated nutrient management (INM) including green and brown manuring could be the major C management practices under irrigated lands of India. Research results indicated that in the surface soil, mean of 11 multi-location studies across India, C sequestration rates under CA was 0.73 Mg C ha"1 year1. Conservation agriculture mainly positively affect the labile C pools, glomalin and C cycling enzymes, and protect C within microaggregates inside macroaggregates. Mean of 12 multi-location trials, carbon sequestration rates under INM was 0.29 Mg C ha"1 year"1. Thus intensive tillage in INM was the major factor of reduced C sequestration rates. Inclusion of pulses and cover crops in cereal-cereal rotations had higher mean C sequestration rates than that of INM. Hence, farmers should adopt these management practices in the irrigated lands of India to enhance SOC and offset global warming.