The recent extreme downpour-caused destruction in the Kodagu district of Karnataka has raised many red flags among researchers. The area is the starting point of the river Kaveri and is home to India’s coffee production. A multi-country research team of scientists from Brazil, France and India has been studying the two widely grown coffee varieties, the Coffea arabica and the Coffea robusta. They researched the contrasting management systems of the coffee plantations especially with reference to the native and exotic shade trees of silver oak (Grevillera robusta). They measured carbon storage and shade tree diversity in native forests and the two coffee agro-forestry systems at 67 plots along a slope that receives 3500 mm of rain in the Kaveri watershed in southern India. The researchers concluded that while the native coffee plantations and forests have comparable carbon stocks and tree diversity as the original forests, and introducing exotic shade trees, such as silver oak, reduces these carbon stocks and tree diversity. The same can be said of the recent trend of switching from Coffea arabica to C. robusta agroforestry systems, which is a practice that is affecting carbon storage in coffee farms of the study area, which negatively affects carbon storage and tree diversity, especially in the robusta coffee systems. The research and findings add to previous and ongoing concerns which have been raised over the wisdom of the introduction of silver oak in coffee plantations, brought out by the CAFNET study, a research program “Connecting, enhancing and sustaining environmental services and market values of coffee agroforestry in Central America, East Africa and India (CAFNET)”.
With India opening to the international coffee market and intensifying its coffee production, coffee farmers are opening the tree shade to produce more coffee. This has resulted in a reduction in density and diversity of shade trees and associated biodiversity, the CAFNET study noted. The farmers’ preference for the fast-growing silver oak is mainly due to free harvest and sale which is not possible for other native trees. The quality of coffee is also influenced by the tree cover, native and exotic and within native trees, it varies with different tree species. as pointed out by researchers. It was pointed out that the exotic shade trees were primarily planted to provide supplemental income for the farmers who find it extremely difficult to harvest, transport and sell native trees. Hence, there is a need of strong policy support to balance the farmers’ needs of supplemental income with the maintenance of a sufficient amount of native shade trees and forest areas in the landscape, thus reaching a balance of biodiversity.

— As reported by Mongabay

Cover Photo: Traditionally coffee is grown under the shade of the rainforest in Kodagu. Photo by S. Gopikrishna Warrier/Mongabay.