Climate Change Mitigation and Adaptation through Conservation Agriculture and Precise Nutrient Management in Current and Future Cereal-based Cropping Systems of the Indo Gangetic Plains

The project aims to quantify the soil and environmental health indicators under conservation agriculture and precise nutrient management to develop strategies to counteract the changing weather conditions, degrading resource use bases on a long-term basis for a sustainable agricultural production and environment system.

IPNI-2013-IND-520

25 Mar 2015

2014 Annual Interpretive Summary


The soil organic carbon (SOC) dynamics and changes in SOC stock has significance with respect to climate change mitigation and sustainability of agricultural production systems. The present study in its final year measured on-site SOC content and its spatial distribution in the Upper Gangetic Plain (UGP) zone of India to establish the cause-effect relationship between agro-ecological characteristics, prevailing crop management practices, and SOC stock. The Northern Gangetic Plains of India covers 37 districts of the State of Uttar Pradesh and two districts of the State of Uttarakhand. The UGP covers five National Agricultural Research Project (NARP) zones including the Bhabar and Tarai zone (BTZ), Mid-western Plain zone (MWPZ), Western Plain zone (WPZ), Southwestern Plain zone (SWPZ), and Central Plain zone (CPZ). Over 70% of the geographical area of the region is cultivated with a cropping intensity of 146%. Nearly 65% of the cultivated area of the region is irrigated. This zone falls under semi-arid to sub-humid climatic conditions, with mean annual rainfall between 595 and 1400 mm. The topography is fairly level to very gently sloping (0 to 3% slope). The soils of this zone are generally deep (>1 m depth) alluvial loams. In general, soils are neutral in pH and have moderate clay and low organic carbon content.

An Area Spread Index (ASI) approach was used to collect soil samples from the NGP areas supporting pre-dominant cropping systems. Exponential ordinary kriging was found to be the most suitable geo-statistical model for developing SOC surface maps of the UGP. Predicted surface maps indicated that 43.7% of the UGP area had 0.5 to 0.6% SOC, while the rest of the area was equally distributed with higher (0.61 to 0.75%) and lower (<0.5%) SOC content. Averaged across cropping systems, maximum SOC content was recorded in BTZ, followed by CPZ, MWPZ, WPZ, and SWPZ. The SOC stock was above the optimum threshold (>12.5 t C/ha) in 97.8%, 57.6% and 46.4% of areas within the BTZ, CPZ and MWPZ, respectively. Only 9.8% and 0.4% of the area within WPZ and SWPZ had SOC stock above the threshold value. The variation in SOC stock was attributed largely to carbon addition through crop biomass and organic recycling, cropping systems, tillage intensity, crop/residue cover and land use efficiency, nutrient use pattern, soil texture, ground water quality, and the prevailing ecosystem. Adoption of conservation agriculture, balanced and integrated nutrient application to crops, inclusion of legumes in cropping systems and agro-forestry were suggested measures for enhancing SOC stock in the region.