Over the past decade, a large number of African countries have undergone or are in the process of... more Over the past decade, a large number of African countries have undergone or are in the process of implementing water sector reforms. The reforms have generally been driven by international calls for more efficient and sustainable water management approaches. The need for a global water management review has gathered momentum since the United Nations Convention on Sustainable Development – the Earth Summit – held in Rio de Janeiro in 1992. The modern focus of water management efforts has been to consider the environment as a legitimate user. In the process, efforts towards pollution control have intensified, with the “user pays ” principle being adopted by many countries. Water management functions have also been decentralized to the catchment or watershed scale where stakeholders have a larger say in the
This project will investigate and study constraints and opportunities that determine adoption of ... more This project will investigate and study constraints and opportunities that determine adoption of rainwater systems innovations and conditions and approaches for farmers-led adoption of the innovations. Its focus is the Pangani River Basin, Tanzania, and aims to develop a framework for participatory knowledge sharing, that can contribute to faster and higher adoption rates of rainwater systems innovations. It is expected that the contribution of this study will improve the understanding of on-farm, off-farm, farmer, and non-farmer factors influencing farmer decision-making and driving or hindering adoption of water systems innovations at farm level.
Physics and Chemistry of the Earth, Parts A/B/C, 2018
The Mana Pools flood plain along the Middle Zambezi River and part of the popular Mana Pools Nati... more The Mana Pools flood plain along the Middle Zambezi River and part of the popular Mana Pools National Park of Zimbabwe has been experiencing both ecological and morphological changes since the construction of upstream hydropower reservoirs. This study investigated the hydro-dynamics from natural and human influenced flows, particularly at the Mana Pools floodplains which are downstream of Kariba and Kafue hydropower dams. Descriptive statistics were used to analyse the differences in flow regime upstream and downstream of the hydropower reservoirs. A standard t-test was done to compare the natural and modified mean annual flows. Results show that the presence of upstream reservoirs has reduced the high peak average monthly flows by 17% and increased the average monthly low flows by 5% at Mana Pools. However, the mean annual runoff has not significantly changed. Results also established that. In line with recent calls for ecological considerations in reservoir management, the study recommends that the reservoir operation in the Middle Zambezi River should mimic the pre-impoundment Middle Zambezi River flow regime at Mana Pools.
This study investigates propagation effects of CMORPH rainfall estimation errors on streamflow si... more This study investigates propagation effects of CMORPH rainfall estimation errors on streamflow simulation for a headwater catchment of the Zambezi River. Model simulations (2006-2012) by the Representative Elementary Watershed (REW) framework are carried out for uncorrected and for bias corrected CMORPH product (the Climate Prediction Center Morphing
Physics and Chemistry of the Earth, Parts A/B/C, 2020
Rapid advancements in technologies open up possibilities for water resource authorities to increa... more Rapid advancements in technologies open up possibilities for water resource authorities to increase their ability to accurately, safely and efficiently establish river flow observation through remote and non-intrusive observation methods. Low-cost Unmanned Aerial Vehicles (UAVS) in combination with Global Navigation Satellite Systems (GNSS) can be used to collect geometrical information of the riverbed and floodplain. Such information, in combination with hydraulic modelling tools, can be used to establish physically based relationships between river flows and permanent proxy. This study proposes a framework for monitoring volatile, dangerous and difficult to access rivers using only affordable and easy to maintain new technologies. The framework consists of four main components: i) establishment of geometry using airborne photogrammetry and bathymetry; ii) physically based rating curve development through hydraulic modelling of surveyed river sections; iii) determination of non-intrusive observations with for instance simple cameras or satellite observations; and iv) evaluating the institutional and societal impacts of using new technology. To establish this framework, a number of research questions require addressing. First, the factors impacting on accuracy of geometrical information of the floodplain terrain and bathymetry need to be investigated. Second the accuracy of a physically based rating curve compared to a traditional rating curve needs to be established. Third, for rapidly changing river segments, it should be investigated if the collection of occasional snapshots of multiple proxies for flow can be used to assess the uncertainty of river flows. The study finally explores the social and institutional impact of using new technologies for remote river monitoring. If these research gaps are addressed, this may strengthen water manager's ability to observe flows and extend observation networks.
Physics and Chemistry of the Earth, Parts A/B/C, 2018
Innovative solutions for intractable water problems in the face of climate change in southern and... more Innovative solutions for intractable water problems in the face of climate change in southern and East African sub regions 1. Introduction This issue has a total of thirty-two (32) papers; and covers the IWRM sub themes of Hydrology, Land and People, Water Resources Management, Water and Environment and Wastewater and Sanitation. Water issues have become more and more complex as the supply side is affected by issues of quantity, availability and vulnerability due to natural factors such as climate change and urbanization. These challenges call for new management strategies and governance styles. Access to clean freshwater is a basic requirement for enhanced quality of life and development by all. However, this access has three main components that must be met adequately as this issue illustrates. These components are firstly, the quantity of water available; secondly, the quality and thirdly supply and appropriate delivery of this precious resource to domestic, commercial and industrial users. The demand side has also become more challenging, especially in urban areas as more and more people move from the rural areas to the cities. It has become a daily challenge in many African cities to supply water to these new urban dwellers and more so in unplanned settlements. These issues require a way and manner of delivering solutions and new innovative ideas. The topics in this issue vary from climate variability and how we are to improve our management strategies to mitigation, through to vulnerability of water resources and how to strengthen governance issues that plague some institutions in our region.
Physics and Chemistry of the Earth, Parts A/B/C, 2019
Mapping floods in the Middle Zambezi Basin using Earth observation and hydrological modeling tech... more Mapping floods in the Middle Zambezi Basin using Earth observation and hydrological modeling techniques The Lower Middle Zambezi catchment, on the Zimbabwean side, is vulnerable to floods almost every year. In this work, the causes and impacts of floods in the Mbire District of the Middle Zambezi Basin are investigated. An algorithm based on the binary logistic regression is used together with MODIS NDVI images to determine the spatial and temporal variation of flood inundation. The HEC-HMS model is used to simulate rainfall time series at daily time step. The quantified peak flow is given as an input to a mono-dimensional hydraulic model, HEC-RAS. Results from the mapped inundated areas for the period 2005 to 2015 showed that 16 January 2006 had the highest flooded area of 1934 km 2. Factors explaining causes of flooding were distance from surface water bodies. The simulated flooded areas obtained are used to deepen our understanding of the contribution of geomorphic features towards flooding as well as the extent of flooding. Results obtained contribute towards defining new strategies for prompt flood risk management in the District.
For evaluation of the Climate Prediction Center-MORPHing (CMORPH) satellite rainfall product in t... more For evaluation of the Climate Prediction Center-MORPHing (CMORPH) satellite rainfall product in the Zambezi Basin, daily time series (1998-2013) of 60 rain gauge stations are used. Evaluations for occurrence and rain rate are at sub-basin scale and at daily, weekly, and seasonal timescale by means of probability of detection (POD), false alarm ratio (FAR), critical success index (CSI) and frequency bias (FBS). CMORPH predicts 60% of the rainfall occurrences. Rainfall detection is better for the wet season than for the dry season. Best detection is shown for rainfall rates smaller than 2.5 mm/day. Findings on error decomposition revealed sources of Hit, Missed and False rainfall bias. CMORPH performance (detection of rainfall occurrences and estimations for rainfall depth) at sub-basin scale increases when daily estimates are accumulated to weekly estimates. Findings suggest that for the Zambezi Basin, errors in CMORPH rainfall should be corrected before the product can serve applications such as in hydrological modelling that largely rely on reliable and accurate rainfall inputs.
The Lower Middle Zambezi Basin is sandwiched between three hydropower dams; Kariba, Kafue (Itezhi... more The Lower Middle Zambezi Basin is sandwiched between three hydropower dams; Kariba, Kafue (Itezhi-tezhi) and Cahora Bassa. The operation of the upstream dams impacts on the inflows into the downstream Cahora Bassa Dam which, in turn, affects the area inundated upstream of the Cahora Bassa Dam. This study applied a rainfall-runoff model (HEC-HMS) and GIS techniques to estimate both the gauged and ungauged runoff contribution to the water balance of Cahora Bassa. The rivers considered in the study are the Zambezi, Kafue, Luangwa, Chongwe, Musengezi and Manyame. Missing data were generated using the mean value infilling method. The DEM hydro-processing technique was used to determine the spatial extent of the ungauged area. A hydrological model, HEC-HMS, was used to simulate runoff from the ungauged catchments. Results from the study show that the ungauged catchment contributes about 12% of the total estimated inflows into the Cahora Bassa Dam. Averaged results over 30 years show total inflows of 71.73 x 10 9 m 3 /yr, total outflows of 52.25 x 10 9 m 3 / yr and a residual storage of 20 x 10 9 m 3 /yr. The study successfully estimated the water balance of the Middle Zambezi Basin which, in turn, may help to inform the operation of the Cahora Bassa Dam and management of artificial floods in the basin.
Hydrology and Earth System Sciences Discussions, 2017
Satellite rainfall estimates (SRE) are prone to bias because such estimates are indirectly derive... more Satellite rainfall estimates (SRE) are prone to bias because such estimates are indirectly derived from visible, infrared, and/or microwave based information of cloud properties. We tested the influence of elevation and distance from large scale water bodies on bias for Climate Prediction Center-MORPHing (CMORPH) rainfall estimates. Effectiveness of five linear/non-linear and time-space variant/invariant bias correction schemes is evaluated. Evaluation also covers for different magnitudes of daily rainfall and climatic seasonality. We used daily rain gauge time series…
Hydrology and Earth System Sciences Discussions, 2016
Obtaining reliable records of rainfall from satellite rainfall estimates (SREs) is a challenge as... more Obtaining reliable records of rainfall from satellite rainfall estimates (SREs) is a challenge as SREs are an indirect rainfall estimate from visible, infrared (IR), and/or microwave (MW) based information of cloud properties. SREs also contain inherent biases which exaggerate or underestimate actual rainfall values hence the need to apply bias correction methods to improve accuracies. We evaluate the performance of five bias correction schemes for CMORPH satellite-based rainfall estimates. We use 54 raingauge stations in the Zambezi Basin for the period 1998-2013 for comparison and correction. Analysis shows that SREs better match to
The challenge of water scarcity as a result of insufficient seasonal rainfall and dry spell occur... more The challenge of water scarcity as a result of insufficient seasonal rainfall and dry spell occurrences during cropping seasons is compounded by inefficient agricultural practices by smallholder farmers where insignificant soil and water conservation efforts are applied. The hypothesis of this research is that many of the past research efforts have taken a fragmented approach to deal with the challenges facing subsistence farmers in rainfed systems The research has been conducted in the semi-arid Makanya catchment of northern Tanzania. The research has successfully applied different analytical techniques to better understand soil and water interactions at field scale. It has been successfully demonstrated that there is indeed scope to increase crop water productivity provided the local farmers adopt more efficient cultivation techniques. Substantial yield increases occur as a result of diverting runoff and these further improve when other techniques such as ripping, application of manure and cover cropping are introduced. This confirms that no single solution exists to solve the problem of low yields in rainfed farming systems. However, even with these promising results, the research has shown that there is room to further improve the efficiency of crop water use through improvement in research approaches and exploration of better techniques.
Physics and Chemistry of the Earth, Parts A/B/C, 2014
Most of Southern Africa is affected by extreme weather events, droughts and floods being the most... more Most of Southern Africa is affected by extreme weather events, droughts and floods being the most common. The frequency of floods and droughts in Southern Africa in general, of which the Zambezi River Basin is part of, has been linked to climate change. Droughts and floods impact on the natural environment, and directly and indirectly impact on livelihoods. In the Middle Zambezi River Basin, which is located between Kariba and Cahora Bassa dams, extreme weather events are exacerbated by human activities, in particular the operation of both the Kariba and the Cahora Bassa reservoirs. To understand better, whether, and in what ways extreme weather events impact on livelihoods, this study used both quantitative and qualitative research methods to analyse rainfall variability and coping strategies used by households in the river basin. Data collection was done using semi-structured interviews, focus group discussions and structured questionnaires which were administered to 144 households. An analysis of rainfall variability and Cahora Bassa water level over 23 years was carried out. The study found that perceptions of households were that average rainfall has decreased over the years, and dry-spells have become more frequent. Furthermore, households perceived flood events to have increased over the last two decades. However, the analysis of rainfall variability revealed that the average rainfall received between 1988 and 2011 had not changed but the frequency of dry-spells and floods had increased. The occurrence of floods in the study area was found to be linked to heavy local rain and backflow from Cahora Bassa dam. The study found that households adopted a number of strategies to cope with droughts and floods, such as vegetable farming and crop production in the floodplain, taking on local jobs that brought in wages, planting late and livestock disposals. Some households also resorted to out-migration on a daily basis to Zambia or Mozambique. The study concluded that coping mechanisms were found to be inflexible and poorly suited to adapt to floods and droughts. The study recommends the implementation of adaptation measures such as the cultivation of drought-resistant crop varieties, irrigation and off-farm employment opportunities.
Physics and Chemistry of the Earth, Parts A/B/C, 2014
I would like to acknowledge the guidance of Almighty God in this project. Lord God, You are my Sh... more I would like to acknowledge the guidance of Almighty God in this project. Lord God, You are my Shepherd. Teach me to love you more. My sincere gratitude goes to Waternet for sponsoring me to do my Masters. I know it will go a long way in changing my life. To all Civil Engineering staff in the Faculty of Engineering, I would like to say thank you so much for the guidance and support. I am heavily indebted to my three supervisors, Mr. C. Mabiza, Mr. K. Kujinga and Dr. J. Goldin who tirelessly gave me direction and encouragement. You were really patient with me. Many thanks also go to Mr. J. Michael of CAMPFIRE in Kanyemba, Miss. Sibande of the Department of Civil Protection, Mr. Majaya the Chief Executive of Mbire Rural District Council, Mr. Kavenda of Agritex at Mushumbi, Chief Chapoto Councillor, Mr. Kachasu, and Mr. Murinya of World Vision Zimbabwe To my uncle Mr. S.E. Mapunda, my brother Mr. A. Mapunda, I say thank you.
Over the past decade, a large number of African countries have undergone or are in the process of... more Over the past decade, a large number of African countries have undergone or are in the process of implementing water sector reforms. The reforms have generally been driven by international calls for more efficient and sustainable water management approaches. The need for a global water management review has gathered momentum since the United Nations Convention on Sustainable Development – the Earth Summit – held in Rio de Janeiro in 1992. The modern focus of water management efforts has been to consider the environment as a legitimate user. In the process, efforts towards pollution control have intensified, with the “user pays ” principle being adopted by many countries. Water management functions have also been decentralized to the catchment or watershed scale where stakeholders have a larger say in the
This project will investigate and study constraints and opportunities that determine adoption of ... more This project will investigate and study constraints and opportunities that determine adoption of rainwater systems innovations and conditions and approaches for farmers-led adoption of the innovations. Its focus is the Pangani River Basin, Tanzania, and aims to develop a framework for participatory knowledge sharing, that can contribute to faster and higher adoption rates of rainwater systems innovations. It is expected that the contribution of this study will improve the understanding of on-farm, off-farm, farmer, and non-farmer factors influencing farmer decision-making and driving or hindering adoption of water systems innovations at farm level.
Physics and Chemistry of the Earth, Parts A/B/C, 2018
The Mana Pools flood plain along the Middle Zambezi River and part of the popular Mana Pools Nati... more The Mana Pools flood plain along the Middle Zambezi River and part of the popular Mana Pools National Park of Zimbabwe has been experiencing both ecological and morphological changes since the construction of upstream hydropower reservoirs. This study investigated the hydro-dynamics from natural and human influenced flows, particularly at the Mana Pools floodplains which are downstream of Kariba and Kafue hydropower dams. Descriptive statistics were used to analyse the differences in flow regime upstream and downstream of the hydropower reservoirs. A standard t-test was done to compare the natural and modified mean annual flows. Results show that the presence of upstream reservoirs has reduced the high peak average monthly flows by 17% and increased the average monthly low flows by 5% at Mana Pools. However, the mean annual runoff has not significantly changed. Results also established that. In line with recent calls for ecological considerations in reservoir management, the study recommends that the reservoir operation in the Middle Zambezi River should mimic the pre-impoundment Middle Zambezi River flow regime at Mana Pools.
This study investigates propagation effects of CMORPH rainfall estimation errors on streamflow si... more This study investigates propagation effects of CMORPH rainfall estimation errors on streamflow simulation for a headwater catchment of the Zambezi River. Model simulations (2006-2012) by the Representative Elementary Watershed (REW) framework are carried out for uncorrected and for bias corrected CMORPH product (the Climate Prediction Center Morphing
Physics and Chemistry of the Earth, Parts A/B/C, 2020
Rapid advancements in technologies open up possibilities for water resource authorities to increa... more Rapid advancements in technologies open up possibilities for water resource authorities to increase their ability to accurately, safely and efficiently establish river flow observation through remote and non-intrusive observation methods. Low-cost Unmanned Aerial Vehicles (UAVS) in combination with Global Navigation Satellite Systems (GNSS) can be used to collect geometrical information of the riverbed and floodplain. Such information, in combination with hydraulic modelling tools, can be used to establish physically based relationships between river flows and permanent proxy. This study proposes a framework for monitoring volatile, dangerous and difficult to access rivers using only affordable and easy to maintain new technologies. The framework consists of four main components: i) establishment of geometry using airborne photogrammetry and bathymetry; ii) physically based rating curve development through hydraulic modelling of surveyed river sections; iii) determination of non-intrusive observations with for instance simple cameras or satellite observations; and iv) evaluating the institutional and societal impacts of using new technology. To establish this framework, a number of research questions require addressing. First, the factors impacting on accuracy of geometrical information of the floodplain terrain and bathymetry need to be investigated. Second the accuracy of a physically based rating curve compared to a traditional rating curve needs to be established. Third, for rapidly changing river segments, it should be investigated if the collection of occasional snapshots of multiple proxies for flow can be used to assess the uncertainty of river flows. The study finally explores the social and institutional impact of using new technologies for remote river monitoring. If these research gaps are addressed, this may strengthen water manager's ability to observe flows and extend observation networks.
Physics and Chemistry of the Earth, Parts A/B/C, 2018
Innovative solutions for intractable water problems in the face of climate change in southern and... more Innovative solutions for intractable water problems in the face of climate change in southern and East African sub regions 1. Introduction This issue has a total of thirty-two (32) papers; and covers the IWRM sub themes of Hydrology, Land and People, Water Resources Management, Water and Environment and Wastewater and Sanitation. Water issues have become more and more complex as the supply side is affected by issues of quantity, availability and vulnerability due to natural factors such as climate change and urbanization. These challenges call for new management strategies and governance styles. Access to clean freshwater is a basic requirement for enhanced quality of life and development by all. However, this access has three main components that must be met adequately as this issue illustrates. These components are firstly, the quantity of water available; secondly, the quality and thirdly supply and appropriate delivery of this precious resource to domestic, commercial and industrial users. The demand side has also become more challenging, especially in urban areas as more and more people move from the rural areas to the cities. It has become a daily challenge in many African cities to supply water to these new urban dwellers and more so in unplanned settlements. These issues require a way and manner of delivering solutions and new innovative ideas. The topics in this issue vary from climate variability and how we are to improve our management strategies to mitigation, through to vulnerability of water resources and how to strengthen governance issues that plague some institutions in our region.
Physics and Chemistry of the Earth, Parts A/B/C, 2019
Mapping floods in the Middle Zambezi Basin using Earth observation and hydrological modeling tech... more Mapping floods in the Middle Zambezi Basin using Earth observation and hydrological modeling techniques The Lower Middle Zambezi catchment, on the Zimbabwean side, is vulnerable to floods almost every year. In this work, the causes and impacts of floods in the Mbire District of the Middle Zambezi Basin are investigated. An algorithm based on the binary logistic regression is used together with MODIS NDVI images to determine the spatial and temporal variation of flood inundation. The HEC-HMS model is used to simulate rainfall time series at daily time step. The quantified peak flow is given as an input to a mono-dimensional hydraulic model, HEC-RAS. Results from the mapped inundated areas for the period 2005 to 2015 showed that 16 January 2006 had the highest flooded area of 1934 km 2. Factors explaining causes of flooding were distance from surface water bodies. The simulated flooded areas obtained are used to deepen our understanding of the contribution of geomorphic features towards flooding as well as the extent of flooding. Results obtained contribute towards defining new strategies for prompt flood risk management in the District.
For evaluation of the Climate Prediction Center-MORPHing (CMORPH) satellite rainfall product in t... more For evaluation of the Climate Prediction Center-MORPHing (CMORPH) satellite rainfall product in the Zambezi Basin, daily time series (1998-2013) of 60 rain gauge stations are used. Evaluations for occurrence and rain rate are at sub-basin scale and at daily, weekly, and seasonal timescale by means of probability of detection (POD), false alarm ratio (FAR), critical success index (CSI) and frequency bias (FBS). CMORPH predicts 60% of the rainfall occurrences. Rainfall detection is better for the wet season than for the dry season. Best detection is shown for rainfall rates smaller than 2.5 mm/day. Findings on error decomposition revealed sources of Hit, Missed and False rainfall bias. CMORPH performance (detection of rainfall occurrences and estimations for rainfall depth) at sub-basin scale increases when daily estimates are accumulated to weekly estimates. Findings suggest that for the Zambezi Basin, errors in CMORPH rainfall should be corrected before the product can serve applications such as in hydrological modelling that largely rely on reliable and accurate rainfall inputs.
The Lower Middle Zambezi Basin is sandwiched between three hydropower dams; Kariba, Kafue (Itezhi... more The Lower Middle Zambezi Basin is sandwiched between three hydropower dams; Kariba, Kafue (Itezhi-tezhi) and Cahora Bassa. The operation of the upstream dams impacts on the inflows into the downstream Cahora Bassa Dam which, in turn, affects the area inundated upstream of the Cahora Bassa Dam. This study applied a rainfall-runoff model (HEC-HMS) and GIS techniques to estimate both the gauged and ungauged runoff contribution to the water balance of Cahora Bassa. The rivers considered in the study are the Zambezi, Kafue, Luangwa, Chongwe, Musengezi and Manyame. Missing data were generated using the mean value infilling method. The DEM hydro-processing technique was used to determine the spatial extent of the ungauged area. A hydrological model, HEC-HMS, was used to simulate runoff from the ungauged catchments. Results from the study show that the ungauged catchment contributes about 12% of the total estimated inflows into the Cahora Bassa Dam. Averaged results over 30 years show total inflows of 71.73 x 10 9 m 3 /yr, total outflows of 52.25 x 10 9 m 3 / yr and a residual storage of 20 x 10 9 m 3 /yr. The study successfully estimated the water balance of the Middle Zambezi Basin which, in turn, may help to inform the operation of the Cahora Bassa Dam and management of artificial floods in the basin.
Hydrology and Earth System Sciences Discussions, 2017
Satellite rainfall estimates (SRE) are prone to bias because such estimates are indirectly derive... more Satellite rainfall estimates (SRE) are prone to bias because such estimates are indirectly derived from visible, infrared, and/or microwave based information of cloud properties. We tested the influence of elevation and distance from large scale water bodies on bias for Climate Prediction Center-MORPHing (CMORPH) rainfall estimates. Effectiveness of five linear/non-linear and time-space variant/invariant bias correction schemes is evaluated. Evaluation also covers for different magnitudes of daily rainfall and climatic seasonality. We used daily rain gauge time series…
Hydrology and Earth System Sciences Discussions, 2016
Obtaining reliable records of rainfall from satellite rainfall estimates (SREs) is a challenge as... more Obtaining reliable records of rainfall from satellite rainfall estimates (SREs) is a challenge as SREs are an indirect rainfall estimate from visible, infrared (IR), and/or microwave (MW) based information of cloud properties. SREs also contain inherent biases which exaggerate or underestimate actual rainfall values hence the need to apply bias correction methods to improve accuracies. We evaluate the performance of five bias correction schemes for CMORPH satellite-based rainfall estimates. We use 54 raingauge stations in the Zambezi Basin for the period 1998-2013 for comparison and correction. Analysis shows that SREs better match to
The challenge of water scarcity as a result of insufficient seasonal rainfall and dry spell occur... more The challenge of water scarcity as a result of insufficient seasonal rainfall and dry spell occurrences during cropping seasons is compounded by inefficient agricultural practices by smallholder farmers where insignificant soil and water conservation efforts are applied. The hypothesis of this research is that many of the past research efforts have taken a fragmented approach to deal with the challenges facing subsistence farmers in rainfed systems The research has been conducted in the semi-arid Makanya catchment of northern Tanzania. The research has successfully applied different analytical techniques to better understand soil and water interactions at field scale. It has been successfully demonstrated that there is indeed scope to increase crop water productivity provided the local farmers adopt more efficient cultivation techniques. Substantial yield increases occur as a result of diverting runoff and these further improve when other techniques such as ripping, application of manure and cover cropping are introduced. This confirms that no single solution exists to solve the problem of low yields in rainfed farming systems. However, even with these promising results, the research has shown that there is room to further improve the efficiency of crop water use through improvement in research approaches and exploration of better techniques.
Physics and Chemistry of the Earth, Parts A/B/C, 2014
Most of Southern Africa is affected by extreme weather events, droughts and floods being the most... more Most of Southern Africa is affected by extreme weather events, droughts and floods being the most common. The frequency of floods and droughts in Southern Africa in general, of which the Zambezi River Basin is part of, has been linked to climate change. Droughts and floods impact on the natural environment, and directly and indirectly impact on livelihoods. In the Middle Zambezi River Basin, which is located between Kariba and Cahora Bassa dams, extreme weather events are exacerbated by human activities, in particular the operation of both the Kariba and the Cahora Bassa reservoirs. To understand better, whether, and in what ways extreme weather events impact on livelihoods, this study used both quantitative and qualitative research methods to analyse rainfall variability and coping strategies used by households in the river basin. Data collection was done using semi-structured interviews, focus group discussions and structured questionnaires which were administered to 144 households. An analysis of rainfall variability and Cahora Bassa water level over 23 years was carried out. The study found that perceptions of households were that average rainfall has decreased over the years, and dry-spells have become more frequent. Furthermore, households perceived flood events to have increased over the last two decades. However, the analysis of rainfall variability revealed that the average rainfall received between 1988 and 2011 had not changed but the frequency of dry-spells and floods had increased. The occurrence of floods in the study area was found to be linked to heavy local rain and backflow from Cahora Bassa dam. The study found that households adopted a number of strategies to cope with droughts and floods, such as vegetable farming and crop production in the floodplain, taking on local jobs that brought in wages, planting late and livestock disposals. Some households also resorted to out-migration on a daily basis to Zambia or Mozambique. The study concluded that coping mechanisms were found to be inflexible and poorly suited to adapt to floods and droughts. The study recommends the implementation of adaptation measures such as the cultivation of drought-resistant crop varieties, irrigation and off-farm employment opportunities.
Physics and Chemistry of the Earth, Parts A/B/C, 2014
I would like to acknowledge the guidance of Almighty God in this project. Lord God, You are my Sh... more I would like to acknowledge the guidance of Almighty God in this project. Lord God, You are my Shepherd. Teach me to love you more. My sincere gratitude goes to Waternet for sponsoring me to do my Masters. I know it will go a long way in changing my life. To all Civil Engineering staff in the Faculty of Engineering, I would like to say thank you so much for the guidance and support. I am heavily indebted to my three supervisors, Mr. C. Mabiza, Mr. K. Kujinga and Dr. J. Goldin who tirelessly gave me direction and encouragement. You were really patient with me. Many thanks also go to Mr. J. Michael of CAMPFIRE in Kanyemba, Miss. Sibande of the Department of Civil Protection, Mr. Majaya the Chief Executive of Mbire Rural District Council, Mr. Kavenda of Agritex at Mushumbi, Chief Chapoto Councillor, Mr. Kachasu, and Mr. Murinya of World Vision Zimbabwe To my uncle Mr. S.E. Mapunda, my brother Mr. A. Mapunda, I say thank you.
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Papers by H Makurira