IMPACTS OF RAINFALL VARIABILITY AND DROUGHT ON FOOD SECURITYAND SMALLHOLDER FARMERS' ADAPTATION STRATEGIES IN GUJI ZONE, OROMIA REGIONAL STATE, ETHIOPIA

Abstract

Rainfall distribution and trends reveal spatial and temporal variability which has a significant impact on smallholder farmers' livelihood. This research sought to examine spatio-temporal variability and trends of spring and autumn rainfall, characterize drought, and assess perceptions of smallholder farmers towards the impacts of rainfall variability and drought on food security and adaptation strategies across three Agro ecological Zones (AEZs). Primary data were collected via sample survey, key informant interviews, and focus group discussions. Gridded rainfall time series data were obtained from the Ethiopian Meteorological Institute from 1990-2020, besides different published and unpublished data sources were used. The onset and cessation date of rainfall was determined using Walter's formulation. The Mann Kendall trend test was employed to detect the trend of rainfall and drought, while Sen's slope was used to test their magnitude of change. The seasonal and annual variability of rainfall was assessed using Precipitation Concentration Index (PCI) and Coefficient of Variation (CV). The Inverse Distance Weighted Index (IDWI) was used to interpolate the spatial distributions of annual and seasonal rainfall. The Reconnaissance Drought Index (RDI) was applied to analyze the severity, duration, and spatial coverage of drought. The Household Food Security Access Scale (HFIAS) was used to analyze the level of food insecurity across the three AEZ of East Guji Zone. The binary logistic econometric model was used to identify determinants of food security and adaptation techniques of smallholder farmers in the study area. Descriptive statistics were used at every level of data analysis. Geographic Information System, Excel stat, SPSS and DrinC 1.7 software programs were utilized to examine quantitative data. The findings demonstrated that altitude and rainfall decrease as one descends from the western (highland AEZ) to the eastern (lowland AEZ) in the study area. Rainfall in the study area varies from the lowland Negele (624mm) which recorded the smallest to the highland Solemo (1262mm) the highest mean annual rainfall. Similarly, the mean length of the growing season declines from the western to eastern part of the study area. The PCI of the lowlands, midlands, and highlands AEZs were 19 %, 17%, and 12 % respectively implying that both lowlands and midlands had an irregular distribution of rainfall while highlands had moderately concentrated rainfall distribution. In contrast, the low and midlands had shown high variability of rainfall (CV >30%) in all seasons. Conversely, the highland's CV suggests moderate variability of rainfall (CV <30 %), with values of 28%, 29 %, and 29% in the spring, summer, and autumn seasons respectively. Moreover, a significant (p< 0.05) increasing trend of annual rainfall was observed in the highlands AEZs (Bore 15.3 mm/year and Solemo14.6 mm/year), in the lowland AEZs (Chembe 10.9 mm/year, Dawa 8 mm/year and Bitata 7.8 mm/year) as well as in the midland AEZs (Kercha 14.5 mm/year). In the meantime, drought has shown statistically significant (p <0.05) declining trend in the autumn and annual (12 months) drought in the highland AEZs (Bore and Solemo), in the midland (Kercha) and in the lowlands (Chembe and Dawa). Food insecurity increases from high to mid and lowlands in the same manner with the increase in seasonal rainfall variability from high to mid and lowlands (CV >30). The finding indicates that food insecurity decreases from lowlands through midlands to highlands. Based on the HFIAS of the lowland AEZ (Negele) was severely food insecure (17.5), midland (Adola) was moderately food insecure (11.3) and highland (Bore) was mildly food insecure with (8.7) value. The results of the binary logistic model revealed that age and sex of the household head, household size, cultivated land size, farming experience, AEZ, size of the tropical livestock unit, level of education, distance from the market and receipt of food aid all positively contribute to household food security significantly at (p <0.05).On the other hand, factors that are less likely to predict households' food security include marital status, access to credit, and access to drought resistant crops. The most popular adaptation strategies pursued by the smallholder farmers of the study area were planting eucalyptus trees (planting trees) in place of food crops, utilizing drought-resistant crop varieties, and mixed cropping. The significant (p <0.05) factors which determine choices of adaptation strategies were AEZ, sex of the HH, household size, size of the tropical livestock unit, level of educational HH, having enough food, obtaining food aid, and time to reach to the local market. Since shortage and variability of rainwater has been identified as a serious problem, strategies should be designed to use additional water resources for irrigation, supplying irrigation pumps, providing short-cycle growth, and drought-resistant crops in the midlands and lowlands AEZ. Adaptation methods; Agro ecological zone; East Guji; Food security; Rainfall variability and Drought; Perception