| Summary: | 碩士 === 國立屏東科技大學 === 熱帶農業暨國際合作系所 === 97 === As the world population continues to grow, so does the need to constantly increases food production. Several actions are required to cope with this increasing demand. Globally, the core challenge must be to improve water productivity. Where land is limiting, yields per unit area must also be enhanced. These measures lead to two basic development directions; increasing the yield in areas where present levels of production are close to their potential; closing the yield gap where considerable production gains can be achieved with current technologies. Based on the above scenarios, studies were carried out to develop irrigation agriculture in Malawi. The studies were done based on climatic data and crop information collected from different areas of Malawi. By considering the fact of improving water productivity, seasonal temperature-based method of estimating reference evapotranspiration based on FAO Penman Monteith (FPM) equation was established for different study sites. Furthermore it has been confirmed that when a single climatic variable such as wind speed, relative humidity or sunshine duration is missing, its estimated value from the FPM missing data procedure can be used for accurate ETo computation in Malawi. The thesis also, examines the scope for meeting the crop water demand under rainfed condition based on the suitable planting period approach in Ouagadougou of Burkina Faso and Ngabu of Malawi. The rainfall contribution index and yield estimation model were introduced to examine the availability of rainwater to suffice the crop water demand and then predicting the yields. Following the suitable planting periods determined in this study might increase the yield of maize, bean, millet, and groundnuts by 10.31, 16.22, 10.57, and 4.82 % in Ouagadougou, and 5.00, 7.41, 7.14, and 4.30 % in Ngabu, respectively. This paper also presents the results of feasibility analysis of using solar powered pump for irrigation in Chileka. The 0.5Hp pump was analyzed if it can be used for irrigation of beans, maize and tomato. The system was compared with rainfed production by taking the yield gap as the gain from the system. The results show that, the energy is enough for the studied PVP system for irrigation in Chileka. However, based on the economic analysis, the system is only viable for irrigation of tomato. The use of the PVP system is therefore strongly recommended for irrigation of tomato in Chileka to promote social and economic development through sustainable irrigated agriculture which is the overall Malawi government’s policy. Another study was done on soil moisture monitoring using results of soil tests from National Pingtung University of Science and Technology experimental field. The soil information was linked with the climatic condition of Malawi to determine irrigation interval by assuming similar soil condition in the study sites. The soil was determined to be clay loam and monthly constants for each site were obtained and recommended for monitoring soil moisture and determination of irrigation interval. Therefore, strategies based on different scenarios presented in this thesis are recommended to ensure the efficient and sustainable use of water and land for agricultural production.
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