Effect of Rainfall Variability on Rice Production in the Ketu North Municipality, Ghana

Rice is an important crop cultivated as a food and cash crop in Ghana. Rice production is highly dependent on rainfall, and hence any changes in the pattern of rainfall could significantly impact its production. Despite this, there is a dearth of evidence on the effect of rainfall variability on rice production in Ghana. The key practices utilized by rice farmers to address the effects of rainfall variability and the barriers militating against the effective implementation of such practices have also not been adequately highlighted in the literature. This study uses a mixed-method approach, including household surveys with 200 rice farmers and five focus group discussions, to investigate the effect of rainfall variability on rice production in four selected communities (Agorvega, Atsikpey, Avalevi, and Gagodope) in the Ketu North Municipality, Ghana. The study specifically sought to (i) determine the perception of smallholder rice farmers on rainfall variability in the studied municipality; (ii) assess the extent of rainfall changes in the studied municipality for the period 2010–2021; (iii) determine the relationship between rainfall variability and rice production; (iv) identify the key adaptation practices used by the smallholder rice farmers to address the effects of rainfall variability; and (v) determine the key barriers confronting the smallholder rice farmers in implementing these adaptation practices. The Mann–Kendall trend test was used to determine the extent of rainfall changes in the municipality, while Sen's slope estimator was used to evaluate the slope of the trend. Pearson's correlation coefficient was used to test the degree of linear correlation between rainfall and rice production. Results showed that the smallholder rice farmers perceived the changes in rainfall through the unpredictable and early onset of rains, as well as increasing annual rainfall. The trend analysis indicated an increase in annual rainfall from 2010 to 2021 (Sen's slope = 8.196; p = 0.150, which is not statistically significant). The insignificant increase in annual rainfall significantly correlated with the average yield of rice (r = 0.614, p = 0.034) and total annual rice production (r = 0.576, p = 0.050), contributing to about 37% and 33% of the variability in average rice yield and annual rice production, respectively. Findings also revealed that smallholder rice farmers adopted key practices, including the planting of early maturing rice varieties (96%), application of fertilizers on rice farms (95%), and diversification of rice farming to non-farming activities (84%), to address the effects of rainfall variability. Results also indicated that key barriers such as limited institutional support (96%), lower educational status (96%), and limited access to information on weather forecasts (95%) obstructed the effective implementation of adaptation practices in the studied communities. The study recommends the need for the government to provide interventions for addressing these barriers, including the provision of subsidized improved seeds, fertilizers, and dedicated extension services to rice farmers in the municipality.