Rainfall Variability and its Impact on Rice Productivity in Fogera Plain, Northwest Ethiopia

Abstract

Abstract
The objective of this study was to analyze rainfall variability and its impact on rice
production in the Fogera Plain. The analysis used historical rainfall and yield data
from four stations. Historical daily rainfall and yield data were obtained from the
National Meteorology Agency (NMA) and Amhara Regional State Bureau of
Agriculture, respectively. The rainfall data were subjected to trend and variability
analysis. Partial correlation and multiple regression analyses were used to determine
the relationship and impact of rainfall characteristics on rice yield. Results showed a
decreasing trend of rainfall amount, shortening of the length of the growing period
(LGP), increased the variability of rainfall onset date and dry spell length in the study
area. The analysis revealed that dry spell lengths of 5 days (sp5), 7 days (sp7), 10
days (sp10) and 15 days (sp15) varied over the study areas with dry spells getting
more prevalent in Woreta and Maksegnit compared to Bahir Dar and Gondar
stations. Rice yield was positively and significantly correlated with annual rainfall
amount (0.69**), LGP (0.61**), and a number of rainy days (0.59*). On the other
hand, rice yield was negatively and significantly correlated with rainfall onset date
(-0.693**) and length of a dry spell (-0.62**). Rainfall parameters explained 69% of
the rice yield variability. The study indicated the need for managing rainfall
variability to increase the productivity of rice in the Fogera Plain.