Impact assessment of climate change on the major rice cultivar Ciherang in Indonesia

Abstract
In Asia, where rice is a major crop, there is high concern about the detrimental effects of climate change on rice productivity. Evaluating these effects, considering the country-specific cultivars’ responses to climate, is needed to effectively implement the national adaptation plans to maintain food security under climate change. However, to date, information on the effects of climate change on the local rice cultivars used in developing countries is extremely limited. In the present study, we used a process-based crop growth model, MATCRO-Rice, to predict the impact of climate change on yields of the major local rice cultivar Ciherang in Indonesia during the next 25 years (2018-2042). This model simulated the effects of current to future air temperature, precipitation, and atmospheric carbon dioxide concentration on rice yield. A total of 14 future climate scenarios, derived from a combination of four general circulation models and three or four representative concentration pathway scenarios in the Coupled Model Intercomparison Project Phase 5, were used to consider the uncertainty of the future climate. The results showed that the rice yield was reduced under all climate scenarios, mainly because of the higher air temperature, leading to reduced photosynthetic rates, increased respiration rates, and phenological changes such as acceleration of senescence. The mean yield reduction across the 14 future climate scenarios was 12.1% for all of Indonesia in 2039-2042. Therefore, to maintain yields in Indonesia, rice production needs to adapt to climate change, and especially to higher air temperatures, in the near future.