Sustainable Growing Areas for Sugarcane in Sri Lanka Under a Changing Climate

Climate change causes shifts in areas suitable for cultivating a wide range of crops. Sugarcane is a perennial crop currently grown in the intermediate and dry zones of Sri Lanka. However, there may be shifts in the potential areas for sugarcane cultivation due to climate change. This study thus attempted to analyze the suitability of rain-fed areas for cultivating sugarcane in Sri Lanka under the current and future projected climate. Ecocrop model was used to predict the climatically suitable areas for sugarcane, based on the present and future climate scenarios. Monthly minimum and maximum temperature, monthly mean rainfall, and crop data were used as inputs to the model. Climate data of the baseline period (1971-2000) were evaluated against the projected climate data in 2030 and 2050 under a Representative Concentration Pathway (RCP) of 4.5 and 8.5 emission scenarios of six Global Climate Models Projected changes revealed to increase the area of intermediate zone of the country by 128, 8, 135, and 170% at RCP 4.5, 2030; RCP 8.5, 2030; RCP4.5, 2050, and RCP 8.5, 2050, respectively, compared to baseline status. Areas for optimum temperature range for sugarcane have expanded in future time periods in the country under two scenarios. The excellent suitable areas for cane growth are projected to increase in 2030 by 56 and 47%, under RCP 4.5 and RCP 8.5, respectively. Considering the aggregated effect of temperature and rainfall, areas for sugarcane cultivation in Sri Lanka tend to increase with climate change.