Low - Cost Irrigation Technology, in the Context of Sustainable Land Management and Adaptation to Climate Change in the Kilimanjaro Region

Abstract

Unsustainable land management and poor adaptation to climate change limits agricultural production in different districts in Kilimanjaro Region. The aim of this study was to train farmers on different aspects of Sustainable Land Management (SLM), improve water use efficiency (WUE) through rehabilitation of traditionally managed irrigation schemes and installation of precision irrigation systems in order to compare their performance without such systems and to assess the impact of the interventions on crop yield and water use productivity. Data were collected during land survey and farmers training in selected areas in Kilimanjaro Region using land survey and farmers training techniques. The data showed increased area under irrigation, improved crop yield, farmer income, water use efficiency and production and productivity in drip irrigation system demonstrated plots compared with furrow or gravity irrigation methods. Improved intake and main canal in Ngalachu irrigation scheme had overall all measured parameters but less compared with drip irrigation. Water saved by drip irrigation was greater by between 33 % and 50 % compared with furrow irrigation methods. The data also showed that crop yields and total revenue in drip irrigation were greater by between 25 % and 60 % and 167 % and 400 % respectively compared with the furrow irrigation methods. These results suggest that farmers using drip irrigation systems were able to realize skills and knowledge, less water loss and greater WUE, higher crop yields, higher incomes compared with places without drip irrigation systems or furrow irrigation methods. However, more time is needed to test these technologies in the field so as to have more meaningful results. It is recommended that the technologies as well as rehabilitation of traditional irrigation schemes be up scaled to a larger area and assess their impact to farmers. Targeted agronomic practices such as the choice of appropriate crop/cultivar (i.e. high value crops) for a specific environment as well as planting and harvesting times, adequate plant nutrition, soil management, and weed control should be observed by both farmers and extension staff since such agricultural practices can significantly contribute to improve WUE and farmers income through increased gross margins.

Keywords: Climate change, water use efficiency, canal, total revenue, water harvesting, land, management