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Rebelo L.-M.,International Water Management Institute
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing | Year: 2010

Maps describing the eco-hydrology of inland wetland systems in Africa are needed to identify and implement appropriate adaptive management plans related to land use and land cover. Many African countries lack regional baseline information on the temporal extent, distribution and characteristics of wetlands. This information is provided here in the form of maps which characterize two wetland sites of international importance in Malawi and Mozambique. Multi-temporal L-band Synthetic Aperture Radar (SAR) datasets are combined with Landsat Thematic Mapper and ASTER images, digital elevation models, and vegetation species data to provide information on wetland ecology and hydrology. These data were used as input to a hybrid, Decision Tree classifier and a Principal Components Analysis classification approach to produce maps depicting the spatial distribution of vegetation species and characterizing the wetland dynamics. The maps exhibit classification accuracies of 89% and 84% for the two sites respectively. The L-band SAR datasets have proved to be an essential information source in the production of these maps due to i) frequent cloud cover/smoke which reduces the temporal coverage of optical data, and ii) a systematic observation strategy and frequent image acquisition which enables characterization of the flood dynamics at a high temporal resolution. © 2010 IEEE. Source

Wegerich K.,International Water Management Institute
Central Asian Survey | Year: 2011

This article explores the cooperation after independence on four Central Asian transboundary rivers. The paper shows that, even though the Central Asian states agreed in 1992 to continue with the basic water-sharing principles, new agreements had to be made. New agreements were only made in basins with large-scale water-control infrastructure, which have transboundary significance or are transboundary themselves. The inequitable water allocation between the riparian states has continued and has not triggered new agreements.© 2011 Southseries Inc. Source

Villholth K.G.,International Water Management Institute
Water International | Year: 2013

Groundwater irrigation for smallholder farmers in Sub-Saharan Africa is growing in extent and importance. This growth is primarily driven spontaneously by the farmers themselves, spurred by improved access to low-cost technologies for pumps and drilling services as well as market opportunities for produce. This paper presents a review of the current status and knowledge of the prospects and constraints for sustainable and pro-poor groundwater irrigation in Sub-Saharan Africa. Further unlocking the potential of groundwater irrigation for smallholders will require better integrated approaches, simultaneously addressing groundwater-access constraints as well as enabling factors. © 2013 2013 International Water Resources Association. Source

Yakubov M.,International Water Management Institute
International Journal of Water Resources Development | Year: 2012

Irrigation management transfer (IMT) reforms in most transition economies of Central Asia have largely relied on the funding and expertise of multiple international aid providers. Such reforms are aimed at the establishment of water users associations; however, progress has remained slow and patchy due to poor aid coordination and poor knowledge regarding what works and what does not. This paper argues that a sector-wide impact study is needed to better inform and consolidate local IMT reform. Placing the discourse within the larger domain of evaluation research, this article looks into the approaches, tools, and practical implications of such an impact study. © 2012 Taylor & Francis. Source

Qureshi A.S.,International Water Management Institute
Mountain Research and Development | Year: 2011

The Indus River basin supplies water to the largest contiguous irrigation system in the world, providing water for 90% of the food production in Pakistan, which contributes 25% of the country's gross domestic product. But Pakistan could face severe food shortages intimately linked to water scarcity. It is projected that, by 2025, the shortfall of water requirements will be ∼32%, which will result in a food shortage of 70 million tons. Recent estimates suggest that climate change and siltation of main reservoirs will reduce the surface water storage capacity by 30% by 2025. The per capita water storage capacity in Pakistan is only 150 m 3, compared with more than 5000 m 3 in the United States and Australia and 2200 m 3 in China. This reduction in surface supplies and consequent decreases in groundwater abstraction will have a serious effect on irrigated agriculture. Supply-side solutions aimed at providing more water will not be available as in the past. Current low productivity in comparison with what has been achieved in other countries under virtually similar conditions points to the enormous potential that exists. To harness this potential, Pakistan needs to invest soon in increasing storage capacity, improving water-use efficiency, and managing surface-water and groundwater resources in a sustainable way to avoid problems of soil salinization and waterlogging. Building capacity between individuals and organizations, and strengthening institutions are key elements for sustaining irrigated agriculture in the Indus Basin. © International Mountain Society. Source

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