SIMULATING RICE YIELDS UNDER CLIMATE CHANGE SCENARIOS USING THE CERES-RICE MODEL

2012

English

The effects of climate change on rice production and yield cannot be overlooked in finding measures to increase production and yield. The CERES-Rice (Ver. 4.0) model was calibrated and evaluated for use in simulating rice yields under different climate change scenarios in Ghana using data from the Anum Valley Irrigation Project. Eighteen years of weather data (1989-2006) was used to run the model. The model was found to be sensitive to climatic parameters (temperature, CO2 concentration, solar radiation and rainfall) and had various effects on rice.Simulated rice yields were sensitive to weather years as there was 13% less yield of rice in 1999 compared with 2001. Increases or decreases of temperature by 4 oC from the maximum or minimum, decreased rice yields by 34% as compared to base scenario of 2006. Similar change in temperatures along with an increase in solar radiation by 1 MJ m-2 day-1, decreased rice yield by 32% compared to base scenario. On the other hand, the same changes in temperature from the maximum and minimum, together with an increase in CO2 concentration by 20 ppm from the standard CO2 concentration of 330 ppm, led to a reduction in rice yield of 33%. Simulations demonstrate that the effects of planting dates cannot be overlooked in finding measures to increase rice yield under climate change mitigations. The effects of climate change on rice yield of will depend on the actual patterns of change in rice growing areas. However, the negative impacts can be averted through appropriate measures such as changes in agronomic practices, development of more temperature tolerant rice varieties and effective training of farmers.

Oteng-Darko, P.; Kyei-Baffour, N.; Ofori, E.