Agroeconomic performance of Aguthi, Matanya and Thome smallholder irrigation schemes
The key objectives of smallholder irrigation projects are increasing agricultural production, household incomes, employment generation and ensuring local food security. However, performance of existing projects in line with their objectives is seldom known. This study aimed at assessing the technical and economic performance of Matanya, Thome and Aguthi smallholder irrigation schemes. The first component assessed yield response of maize (hybrid 511) to different levels of irrigation water using 33%, 66% and 100% of the computed irrigation water requirement (IR). The second component assessed agro-economic performance of the schemes with respect to cropping patterns, crop yields, cropping intensities, employment generation and primary sources of food and income by carrying out a field survey on stratified sample households representing the head, middle and tail reaches of the schemes. The results showed that crop height, percentage cover and grain yield were significantly different for Treatment 1 and non-significantly different for Treatment 2 relative to Treatment 3 at 5% level of significance. Crop height and percentage crop cover were highly correlated with r = 0.965, 0.975 and 0.973 at 33%, 66% and 100% IR respectively. Yield response factors (Ky) ranged between 0.77 to 0.85 and 0.11 to 0.17 with means of 0.82 and 0.14 in Treatments 1(33% IR) and 2(66%IR) respectively relativeto Treatment 3(100% IR). Agro-economic performance was found to vary between individual farmers, schemes andscheme sections and skewed in favour of head and middle sections. Differences between scheme sections were attributed to unequitable water allocation that favours head-section farmers. Percentage of total holding size under irrigation generally decreased downstream with a mean of 44.7%,44.8% and 34.3% for the head, middle and tail scheme sections respectively. Irrigation improved cropping patterns through introduction of horticultural crops which were not grown under rain-fed condition. The farmer-reported mean irrigated maize and bean yields were 1377 kg/ha and 1349 kg/ha.Rain-fed yields were 994kg/ha and 978 kg/ha for maize and beans respectively. Cropping intensities were higher under irrigation than under rain-fed condition with xv means of 255.3% and 160.0% respectively. Majority of sample households relied primarily on irrigation for food with 44%, 40.7% and 38.3% in Matanya, Thome and Aguthi respectively. As a primary source of income, irrigation was second after livestock with 26.8%, 26.6% and 30.0 % of sample households being dependent on irrigation in Matanya, Thome and Aguthi respectively. Thome and Aguthi schemes are commercial-oriented whereas Matanya is subsistenceoriented with 57.8%, 65.5% and 41% of the mean irrigated area per household under horticultural crops respectively. Although majority of the sample households depended on family labour, irrigation was the major source of employment with 40%, 30.9% and 52% of the sample households allocating hired labour in irrigation-related activities in Matanya, Thome and Aguthi respectively. Poor water management, low levels of agronomic practices and poor marketing organisation were the key factors constraining agro-economic performance.