摘要
The functions of and services from wetlands are seriously compromised due land and water scarcity coupled with the inability of poor people to adopt sound management strategies. The expansion of rice irrigation into the Ombeyi wetland ecosystem is likely to reduce their long-term ecological functionality. Using field observations and measurements, stakeholder analysis framework and consultative fora, this study investigated the growth in irrigated agriculture, irrigation practices and existing and potential trade-offs between the various uses of the wetland and their ecological functions. The objective was to identify the equilibrium between expansion of area under rice and restoration of the Ombeyi wetland ecosystem. Issues affecting wetland use and management were identified and used to derive possible solutions that could lead to sustainable use of the wetlands. The study showed that the area under rice cultivation increased by up to 760% as compared to the 1970s, most of it into the wetlands. There was a huge dependency on irrigation for food and income generation. However, there was observed low efficiency in water use and management. Recent emerging crops, especially arrow roots, would pose more threats to the wetland ecosystem because of their tolerance to waterlogged soils, low labour input, continuous harvesting and fewer pests and diseases. The fast exhaustion of soil fertility by arrow roots is also likely to motivate expansion into new areas, predominantly the wetlands. It was established that transplanting rice by mid May as opposed to the current practice in which farmers transplant in mid July saves water. The impact could further be reduced if the farmers adopted an optimized seasonal calendar. The study concluded that the solutions to wetland encroachment and over exploitation of resources lie in capacity building of farmers, improving efficiency in resource use and seeking for alternative livelihood options.
The functions of and services from wetlands are seriously compromised due land and water scarcity coupled with the inability of poor people to adopt sound management strategies. The expansion of rice irrigation into the Ombeyi wetland ecosystem is likely to reduce their long-term ecological functionality. Using field observations and measurements, stakeholder analysis framework and consultative fora, this study investigated the growth in irrigated agriculture, irrigation practices and existing and potential trade-offs between the various uses of the wetland and their ecological functions. The objective was to identify the equilibrium between expansion of area under rice and restoration of the Ombeyi wetland ecosystem. Issues affecting wetland use and management were identified and used to derive possible solutions that could lead to sustainable use of the wetlands. The study showed that the area under rice cultivation increased by up to 760% as compared to the 1970s, most of it into the wetlands. There was a huge dependency on irrigation for food and income generation. However, there was observed low efficiency in water use and management. Recent emerging crops, especially arrow roots, would pose more threats to the wetland ecosystem because of their tolerance to waterlogged soils, low labour input, continuous harvesting and fewer pests and diseases. The fast exhaustion of soil fertility by arrow roots is also likely to motivate expansion into new areas, predominantly the wetlands. It was established that transplanting rice by mid May as opposed to the current practice in which farmers transplant in mid July saves water. The impact could further be reduced if the farmers adopted an optimized seasonal calendar. The study concluded that the solutions to wetland encroachment and over exploitation of resources lie in capacity building of farmers, improving efficiency in resource use and seeking for alternative livelihood options.
