The Effects of Rainfall Variability on Cassava, Yam, and Maize Yields in Imo State, Nigeria, 1987-2016
A Correlational Analysis
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Abstract
This research examined the impact of rainfall variability on the production of selected food crops in Imo State from the year 1987 to 2016. Rainfall variability has been one of the major causes of agricultural failures for certain crops in Imo State. Rather than having a study involving a single crop analysis of the relationship between rainfall variability and crop yields, the study used three food crops. The study looked at the state's rainfall and crop yield trends over a 30-year period. To accomplish this goal, the researcher gathered secondary data in the form of rainfall and yield statistics for cassava, yam, and maize during a 30-year period. These data were obtained from the Nigerian Meteorological Agency (NIMET) and the Agricultural Development Programme (ADP) offices in Imo state, based on the state's three agricultural zones (Orlu, Okigwe, and Owerri). Statistical analyses such as ANOVA, Pearson's Product-Moment Correlation Analysis, and Regression analysis were performed on the collected data. Tables and figures were used to present the results. The findings demonstrate that rainfall changed greatly between 1987 and 2016, with the Owerri zone receiving the most total yearly rainfall and the Okigwe zone receiving the least. Furthermore, it was discovered that there was a very weak association between rainfall variance and agricultural yields (negative). Furthermore, the study found that variation in rainfall could only predict 4.7% of the variance in cassava yield, 8.2% of the variance in yam yield, and 12.2% of the variance in maize yield, indicating a negligible effect. Rainfall variability, therefore, affects maize yields more than cassava and yam yields, indicating that other factors such as temperature variations, moisture content, soil fertility, farm practices and management may have influenced the annual yields of the studied crops.
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Copyright (c) 2026 Franklin Chimaobi Okoro (Author)
This work is licensed under a Creative Commons Attribution 4.0 International License.
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