ABSTRACT
Global carbon (C) cycling is intricately connected to cropping systems. Globally, soils contain 1500-1600 Pg C and it is second compared to C found in deep seas, but it is twice the amount traced in atmosphere. Soil organic-C fluctuations can have a major impact on atmospheric CO2 concentration and C cycle in general. Excessive emissions can lead to deterioration of soil quality and induce green house effects. Maize agroecosystem with its expanse at 140 m ha is an important ecological entity that affects C cycle and crop productivity on earth. A sizeable share of soil C sequestration and emissions could be mediated via maize belts of different continents. Maize agroecosystem, individually may offset sizeable fraction of fossil fuel emission through its ability to sequester C into crop and soil phase of the ecosystem. As such, maize is a preferred crop in dry lands that are prone to massive loss of soil organic carbon (SOC) due to repeated tillage, resultant high microbial activity, and soil respiration. The SOC recycling procedures too could be meager in many locations within maize growing regions of the world, because it is preferred better as forage or utilized more frequently for biofuel production. Obviously, there is a strong need to enhance forage recycling and lessen C emissions. It has been aptly pointed out that an increase in 1.0 ton of soil-C pool in degraded or sandy low fertility soil can increase crop productivity by 20-40 kg ha-1. In case of maize, about 10-20 kg grain ha-1 could be enhanced t –1 soil C sequestered (Lal, 2004).
