Climate change effects of adaptation on annual and perennial crop yields in Uganda

Climate change impacts are expected to negatively affect crop productivity in several agricultural systems and agro-ecological zones of Africa, where the majority of the rural people derive their livelihood from rain-fed agriculture. In Uganda, mountainous and lake ecosystems are dominant growing areas for major annual and perennial crops, but are more susceptible to future changes in climate. This is likely to deteriorate agricultural livelihoods of these ecosystems through declining productivity of various crops. This study assessed the near-term future climate change effects of selected adaptation practices on yields of annual and perennial crops in coffee growing agro-ecological zones of Uganda. Based on a Cobb-Douglas logarithmic production function, the study examined whether future climate would increase crop productivity through the influence of adaptation practices at current and increased adoption levels in the near-term under RCP8.5 and RCP4.5 for five climate regimes. The study results showed that rainfall changes, particularly wetter conditions (cool-wet and hot-wet climate regimes) are expected to be the most damaging to coffee, banana, maize and beans yields than temperature changes with drier conditions (including ensemble mean, cool-dry and hot-dry) under various altitude gradients. Hence, current adaptation practices have significant potential to reduce crop yield losses especially if future climate becomes drier than wetter in the near-term. The study therefore, recommends that there is a need for further research to identify complementary adaptation practices e.g. through bioengineering, soil loss control and water draining efficiency technologies; that would boost positive crop productivity effects of current adaptation practices, as they are not sufficient on their own in the near-term future even with enhanced adoption rates. Also, plant breeding programs should focus on generating crop varieties that are drought tolerant but can also perform well in volatile hydrological conditions; and those that are more suitable for the various altitudinal changes in climate.