Climate change will leave all cardamom-coffee hotspots of South India vulnerable while the growth, development and yield of various crops will be impacted negatively, says a study based on long-term climate data from Kerala, Tamil Nadu and Karnataka.

"The study showed more precipitation levels and patterns occurred in Cardamom Hills, followed by lower Puleny Hills in Tamil Nadu. The least variation in precipitation levels has been noticed for temperate upper Puleny Hills and Kodagu Hills in Karnataka," says Dr. Muthusamy Murugan, lead author and Professor, who carried out the study with M. Alagupalamuthirsolai, Kaliyaperumal Ashokkumar, Aavudai Anandhi, Raju Ravi, J. Rajangam, M. K. Dhanya and K. S. Krishnamurthy.

They had analysed long-term climate data from four climate stations in South India and the productivity data of select crops including coffee and cardamom. The study found that cardamom is more climate sensitive compared to coffee. While a 40% dip in annual rainfall hardly affected the yields of coffee in CH during 2017-2018, the cardamom yield was reduced to nearly 50%. Ecophysiological studies of coffee, cardamom, and black pepper also proved that coffee will adapt well to challenging climatic conditions.

"Since all the coffee-cardamom hotspots in southern India undergo considerable change in precipitation levels and pattern, necessary precautions, including water and irrigation management strategies, must be given utmost priority to increase the crop yield sustainability of these delicate cardamom-coffee hotspots in India," says the study.

Another important finding of the study is the change in the tree species composition of cardamom-coffee hotspots over the last three decades.