Effect of Climate-Smart Agriculture Practices on Climate Change Adaptation, Greenhouse Gas Mitigation and Economic Efficiency of Rice-Wheat System in India

Suresh K Kakraliya,Parbodh C Sharma,Hanuman S Jat,Manoj K Gora,Tek B Sapkota,Manish Kakraliya,Mangi L Jat,Ishwar Singh

doi:10.3390/agriculture11121269

Abstract

Conventional rice–wheat (RW) rotation in the Indo-Gangetic Plains (IGP) of South Asia is tillage, water, energy, and capital intensive. Coupled with these, crop residue burning contributes significantly to greenhouse gas (GHG) emission and environmental pollution. So, to evaluate the GHG mitigation potential of various climate-smart agricultural practices (CSAPs), an on-farm research trial was conducted during 2014–2017 in Karnal, India. Six management scenarios (portfolios of practices), namely, Sc1—business as usual (BAU)/conventional tillage (CT) without residue, Sc2—CT with residue, Sc3—reduced tillage (RT) with residue + recommended dose of fertilizer (RDF), Sc4—RT/zero tillage (ZT) with residue + RDF, Sc5—ZT with residue + RDF + GreenSeeker + Tensiometer, and Sc6—Sc5 + nutrient-expert tool, were included. The global warming potential (GWP) of the RW system under CSAPs (Sc4, Sc5, and Sc6) and the improved BAU (Sc2 and Sc3) were 33–40% and 4–26% lower than BAU (7653 kg CO2 eq./ha/year), respectively. This reflects that CSAPs have the potential to mitigate GWP by ~387 metric tons (Mt) CO2 eq./year from the 13.5 Mha RW system of South Asia. Lower GWP under CSAPs resulted in 36–44% lower emission intensity (383 kg CO2 eq./Mg/year) compared to BAU (642 kg CO2 eq./Mg/year). Meanwhile, the N-factor productivity and eco-efficiency of the RW system under CSAPs were 32–57% and 70–105% higher than BAU, respectively, which reflects that CSAPs are more economically and environmentally sustainable than BAU. The wheat yield obtained under various CSAPs was 0.62 Mg/ha and 0.84 Mg/ha higher than BAU during normal and bad years (extreme weather events), respectively. Thus, it is evident that CSAPs can cope better with climatic extremes than BAU. Therefore, a portfolio of CSAPs should be promoted in RW belts for more adaptation and climate change mitigation.

Highlights

The angles between the greenhouse gas (GHG) and sustainability indicators were significantly different. These results show that the area scaled/global warming potential (GWP) were correlated with C-sequestration, N-factor productivity, grain yield, net return, and eco-efficiency (Table 5)
Climate-smart agricultural practices estimated lower CH4 emissions compared to business as usual (BAU), which may be due to avoidance of puddling and less frequent irrigation
Our results suggest that the eco-efficiency of the RW system can be enhanced by the practice of climate-smart agricultural practices (CSAPs), which reduces negative environmental impacts while at the same time maintaining or increasing the net farm income [25]

Summary

Introduction

In the era of climate change, traditional rice farming has been criticized for the elevated level of GHG emissions. In situ burning of crop residue, faulty irrigation management, and indiscriminate use of chemical fertilizers are the main sources of anthropogenic GHG emissions in the RW production system and are accountable for ill effects of climate change [1,2,3,4]. Methane from enteric fermentation and rice cultivation [5] and nitrous oxide emissions from soil and from applied fertilizers [1,6] are major contributors to agricultural GHG emissions. A recent report by the Intergovernmental Panel on Climate

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