Spatiotemporal analysis of projected impacts of climate change on the major C3 and C4 crop yield under representative concentration pathway 4.5: Insight from the coasts of Tamil Nadu, South India.

Ramachandran A,Dhanya Praveen,Jaganathan R,Palanivelu K,Rajalakshmi D,Prasanta K Subudhi

doi:10.1371/journal.pone.0180706

Abstract

India's dependence on a climate sensitive sector like agriculture makes it highly vulnerable to its impacts. However, agriculture is highly heterogeneous across the country owing to regional disparities in exposure, sensitivity, and adaptive capacity. It is essential to know and quantify the possible impacts of changes in climate on crop yield for successful agricultural management and planning at a local scale. The Hadley Centre Global Environment Model version 2-Earth System (HadGEM-ES) was employed to generate regional climate projections for the study area using the Regional Climate Model (RCM) RegCM4.4. The dynamics in potential impacts at the sub-district level were evaluated using the Representative Concentration Pathway 4.5 (RCPs). The aim of this study was to simulate the crop yield under a plausible change in climate for the coastal areas of South India through the end of this century. The crop simulation model, the Decision Support System for Agrotechnology Transfer (DSSAT) 4.5, was used to understand the plausible impacts on the major crop yields of rice, groundnuts, and sugarcane under the RCP 4.5 trajectory. The findings reveal that under the RCP 4.5 scenario there will be decreases in the major C3 and C4 crop yields in the study area. This would affect not only the local food security, but the livelihood security as well. This necessitates timely planning to achieve sustainable crop productivity and livelihood security. On the other hand, this situation warrants appropriate adaptations and policy intervention at the sub-district level for achieving sustainable crop productivity in the future.

Highlights

The majority of the world’s undernourished people live in developing countries
As the crops are highly susceptible to small changes in the microclimatic conditions, the estimates of future crop productivity at microscale would support appropriate actions in the future to curtail the potential impacts
The major crops in the study area, rice, groundnut, and sugarcane, performed in different ways in the emerging scenarios given by Intergovernmental Panel on Climate Change (IPCC) Representative Concentration Pathways (RCPs) 4.5

Summary

Introduction

The majority of the world’s undernourished people live in developing countries. Two-thirds live in just seven countries (Bangladesh, China, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, and Pakistan), with 40 percent living in China and India [1]. Climate change and C3 and C4 crop yield under RCP4.5-South India increasing challenge of food and livelihood insecurity largely depend on the rate of yield gain of the major cereal crops in a country like India [2]. According to the 5th Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC), the global (land and ocean) average temperature has risen 0.85 ̊C (0.65–1.06 ̊C) over the period of 1800– 2012 [3]. This trend in global warming is predicted to increase during the 21st century under all the Representative Concentration Pathways (RCPs). Such changes in global mean temperature can radically disturb human society and the natural environment [5]; the changes in extreme temperature events, such as heat waves, severe winters, summer storms, hot and cold days, and hot and cold nights, may severely impact the agricultural ecosystems [6]

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