The demand of water for irrigation purposes in Tanzania outstrips the amount of water available for irrigation and other demands. On the other hand, the demand for more food to feed the growing population is increasin...The demand of water for irrigation purposes in Tanzania outstrips the amount of water available for irrigation and other demands. On the other hand, the demand for more food to feed the growing population is increasing, calling for the need to have technologies and farming practices that ensure more food production while minimizing water uses. Rice is among cereal crops grown in Tanzania, and it can assist in meeting the food demand for the nation. Majority of rice producers in Tanzania and Sub-Saharan Africa(SSA) are subsistence farmers and they practice continuous flooding, a technique that requires much water. In addition to using large amounts of water, the conventional practices of growing paddy using local varieties transplanting process are implemented when seedlings are more than 21 days old, and 3-4 seedlings are transplanted in one hole. This practice results in low yields, and low water productivity and water use efficiency. The system of rice intensification (SRI) on the other hand, is a promising new practice of growing paddy rice that has proven to be very effective in saving water and increasing rice yields in many parts of the world. SRI practice is spreading fast and it has been adopted in many countries. The SRI practice has been introduced in Tanzania during the last 3 years as such it is not widely practiced. This paper reviews SRI practice at global, regional and country (Tanzania) level, and evaluates the challenges, opportunities and implications for its adoption in Tanzania. Knowledge gaps at each level have been identified and discussed as well as suggestions for researchable areas.展开更多
Energy and environmental sustainability are important considerations for increased rice production. This study examined the energy utilization and sustainability of rice processing in sub-Saharan Africa. The community...Energy and environmental sustainability are important considerations for increased rice production. This study examined the energy utilization and sustainability of rice processing in sub-Saharan Africa. The community of Gadan Loko village in the song local government of Adamawa State, Nigeria was selected as the focus of study. Rice parboiling, the most energy intensive process in rice processing is carried out usually by women in small quantities of about 13.2 kg using traditional pots on tripod support stoves. The parboiled rice is sun dried on mats before it is taken to the milling stalls where it is milled using milling machines driven by single cylinder diesel engines. There were large variations in the quality of milled rice due to lack of consistency in processing parameters. Accumulation of rice husk in the community created important environmental issues. In this study, methods of improving sustainability of rice processing were investigated. The areas included： the utilization of waste heat from the diesel engines for improved drying and efficient pre-soaking; the utilization of solar energy for pre-soaking; the utilization of rice husks as alternative fuel to firewood; and the optimization and redesign of the stoves and parboiling vessels to minimize heat loss to the environment. The results showed that the utilization of rice husk as alternative fuel and the redesign of the stoves and parboiling vessels will increase the sustainability of rice processing and can be easily adopted by the community. While solar energy pre-soaking was not economical and the utilization of waste heat from the diesel engines for drying and pre-soaking would be difficult to implement at the rural scale, because most of the parboiling is done far away from the milling stalls. The study showed that research, development of appropriate technology, and education （RATE） of the rural community is an important way of increasing sustainability.展开更多
文摘The demand of water for irrigation purposes in Tanzania outstrips the amount of water available for irrigation and other demands. On the other hand, the demand for more food to feed the growing population is increasing, calling for the need to have technologies and farming practices that ensure more food production while minimizing water uses. Rice is among cereal crops grown in Tanzania, and it can assist in meeting the food demand for the nation. Majority of rice producers in Tanzania and Sub-Saharan Africa(SSA) are subsistence farmers and they practice continuous flooding, a technique that requires much water. In addition to using large amounts of water, the conventional practices of growing paddy using local varieties transplanting process are implemented when seedlings are more than 21 days old, and 3-4 seedlings are transplanted in one hole. This practice results in low yields, and low water productivity and water use efficiency. The system of rice intensification (SRI) on the other hand, is a promising new practice of growing paddy rice that has proven to be very effective in saving water and increasing rice yields in many parts of the world. SRI practice is spreading fast and it has been adopted in many countries. The SRI practice has been introduced in Tanzania during the last 3 years as such it is not widely practiced. This paper reviews SRI practice at global, regional and country (Tanzania) level, and evaluates the challenges, opportunities and implications for its adoption in Tanzania. Knowledge gaps at each level have been identified and discussed as well as suggestions for researchable areas.
文摘Energy and environmental sustainability are important considerations for increased rice production. This study examined the energy utilization and sustainability of rice processing in sub-Saharan Africa. The community of Gadan Loko village in the song local government of Adamawa State, Nigeria was selected as the focus of study. Rice parboiling, the most energy intensive process in rice processing is carried out usually by women in small quantities of about 13.2 kg using traditional pots on tripod support stoves. The parboiled rice is sun dried on mats before it is taken to the milling stalls where it is milled using milling machines driven by single cylinder diesel engines. There were large variations in the quality of milled rice due to lack of consistency in processing parameters. Accumulation of rice husk in the community created important environmental issues. In this study, methods of improving sustainability of rice processing were investigated. The areas included： the utilization of waste heat from the diesel engines for improved drying and efficient pre-soaking; the utilization of solar energy for pre-soaking; the utilization of rice husks as alternative fuel to firewood; and the optimization and redesign of the stoves and parboiling vessels to minimize heat loss to the environment. The results showed that the utilization of rice husk as alternative fuel and the redesign of the stoves and parboiling vessels will increase the sustainability of rice processing and can be easily adopted by the community. While solar energy pre-soaking was not economical and the utilization of waste heat from the diesel engines for drying and pre-soaking would be difficult to implement at the rural scale, because most of the parboiling is done far away from the milling stalls. The study showed that research, development of appropriate technology, and education （RATE） of the rural community is an important way of increasing sustainability.
