44 research outputs found
Optimising hydropower development and ecosystem services in the Kafue River, Zambia
Fisheries are an important resource in Zambia, but are experiencing overexploitation and are under increasing pressure from external development activities that are compromising river ecosystem services and functioning. One such system is the Kafue Flats floodplain, which is under threat from hydropower development. This paper reviews the impact of potential hydropower development on the Kafue Flats floodplain and explores mechanisms to optimise the expansion of hydropower whilst maintain the ecosystem functioning and services the floodplain delivers.Since completion of the Kafue Gorge and Itezhi-tezhi dams, seasonal fluctuations in the height and extent of flooding have been suppressed. This situation is likely to get worse with the proposed incorporation of a hydropower scheme into Itezhi-tezhi dam, which will operate under a hydropeaking regime. This will have major ramifications for the fish communities and ecosystem functioning and likely result in the demise of the fishery along with destruction of the wetlands and associated wildlife. To redress the problem it is recommended that an environmental flows study is conducted, as initiated by World Wildlife Fund, to protect the existing ecosystem services provision and optimise hydropower development, thus ensuring sustainability of the aquatic resources of the Kafue Flats for future generations
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Science for Humanitarian Emergencies and Resilience (SHEAR) scoping study: Annex 3 - Early warning system and risk assessment case studies
This report provides case studies of Early Warning Systems (EWSs) and risk assessments encompassing three main hazard types: drought; flood and cyclone. The case studies are taken from ten countries across three continents (focusing on Africa, South Asia and the Caribbean).
The case studies have been developed to assist the UK Department for International Development (DFID) to prioritise areas for Early Warning System (EWS) related research under their ‘Science for Humanitarian Emergencies and Resilience’ (SHEAR) programme.
The aim of these case studies is to ensure that DFID SHEAR research is informed by the views of Non-Governmental Organisations (NGOs) and communities engaged with Early Warning Systems and risk assessments (including community-based Early Warning Systems).
The case studies highlight a number of challenges facing Early Warning Systems (EWSs). These challenges relate to financing; integration; responsibilities; community interpretation; politics; dissemination; accuracy; capacity and focus.
The case studies summarise a number of priority areas for EWS related research:
• Priority 1: Contextualising and localising early warning information
• Priority 2: Climate proofing current EWSs
• Priority 3: How best to sustain effective EWSs between hazard events?
• Priority 4: Optimising the dissemination of risk and warning information
• Priority 5: Governance and financing of EWSs
• Priority 6: How to support EWSs under challenging circumstances
• Priority 7: Improving EWSs through monitoring and evaluating the impact and effectiveness of those system
Paleo-geohydrology of Lake Chilwa, Malawi is the source of localised groundwater salinity and rural water supply challenges
Meeting long-term rural community water supply needs requires diligent geohydrological conceptualisation. Study of Malawi’s Lake Chilwa Basin, including sampling of 330 water points in Phalombe District, enabled assessment of groundwater quality influence upon supply. The control of larger Lake Chilwa paleo-environments on current Basin groundwater quality is demonstrated. Lacustrine sediment deposition forming high-level deposits under open lake conditions and terrace deposits under open and closed lake conditions significantly control the groundwater major-ion quality and salinity now observed. Paleo-lake extent marks the transition between low-TDS (total dissolved solids) groundwater suitable for water supply at higher elevations and high-TDS brackish groundwater in areas overlain by lacustrine deposits closer to the current lake level. Low-TDS groundwater is limited to mid-to-low reach influent leakage of rivers incising terraces. Permeable fluvial deposits within the deeper paleo-river channel may possibly provide low-TDS water. The conceptual model, whereby paleo-lake controls groundwater salinity, provides science-based evidence to address policy to manage the significant water point functionality concerns quantified at the district and river basin scales. Targeting of the low-TDS groundwater alongside improved use of upland low-TDS stream/river sources with fewer, but larger capacity, and better maintained gravity-fed supply schemes are recommended. This study hence shows the value of paleo-geohydrology interpretation of the lake–groundwater system conceptualisation to inform Sustainable Development Goal 6 (SDG 6.5.1)—integrated water resources management policy for rural water supply
Virologic outcomes in early antiretroviral treatment: HPTN 052
Introduction: The HIV Prevention Trials Network (HPTN) 052 trial demonstrated that early antiretroviral therapy (ART) prevented 93% of HIV transmission events in serodiscordant couples. Some linked infections were observed shortly after ART initiation or after virologic failure. Objective: To evaluate factors associated with time to viral suppression and virologic failure in participants who initiated ART in HPTN 052. Methods: 1566 participants who had a viral load (VL) > 400 copies/mL at enrollment were included in the analyses. This included 832 in the early ART arm (CD4 350–550 cells/mm3 at ART initiation) and 734 in the delayed ART arm (204 with a CD4 < 250 cells/mm3 at ART initiation; 530 with any CD4 at ART initiation). Viral suppression was defined as two consecutive VLs ≤ 400 copies/mL after ART initiation; virologic failure was defined as two consecutive VLs > 1000 copies/mL > 24 weeks after ART initiation. Results: Overall, 93% of participants achieved viral suppression by 12 months. The annual incidence of virologic failure was 3.6%. Virologic outcomes were similar in the two study arms. Longer time to viral suppression was associated with younger age, higher VL at ART initiation, and region (Africa vs. Asia). Virologic failure was strongly associated with younger age, lower educational level, and lack of suppression by three months; lower VL and higher CD4 at ART initiation were also associated with virologic failure. Conclusions: Several clinical and demographic factors were identified that were associated with longer time to viral suppression and virologic failure. Recognition of these factors may help optimize ART for HIV treatment and prevention
Perverse Market Outcomes from Biodiversity Conservation Interventions
Conservation interventions are being implemented at various spatial scales to reduce the impacts of rising global population and affluence on biodiversity and ecosystems. While the direct impacts of these conservation efforts are considered, the unintended consequences brought about by market feedback effects are often overlooked. Perverse market outcomes could result in reduced or even reversed net impacts of conservation efforts. We develop an economic framework to describe how the intended impacts of conservation interventions could be compromised due to unanticipated reactions to regulations in the market: policies aimed at restricting supply could potentially result in leakage effects through external or unregulated markets. Using this framework, we review how various intervention methods could result in negative feedback impacts on biodiversity, including legal restrictions like protected areas, market-based approaches, and agricultural intensification. Finally, we discuss how conservation management and planning can be designed to ensure the risks of perverse market outcomes are detected, if not overcome, and we address some knowledge gaps that affect our understanding of how market feedbacks vary across spatial and temporal scales, especially with teleconnectedness and increased international trade
Africa: Inside the Triangle of Devaluation, Inflation and Stagnation (article)
The author argues that a policy of devaluation imposed on African economies in compliance with real exchange rate rules contradicts the inflation objectives of fiscal stabilisation because by devaluing a currency at every instance of inflation, it implies that the exchange rate is indexed to the domestic price level via the balance of payments and money supply. Given that one characteristic of African economies is that government is the largest consumer of foreign exchange, in the context of debt service payments, exchange rate depreciation magnifies the public sector net cash requirement and leads to a faster rate of monetary growth, thus resulting in further cyclic inflation. The author also argues that the other effect of devaluation is also to compromise bank balance sheets and lead to contractions in bank lending capacities, which also affect the real economy. This is on account of the fact that African banks hold open speculative positions in foreign exchange, which increase vulnerability of the entire financial system. The author supports the effectiveness of devaluation in changing the vector of relative prices via the price mechanism and therefore operating as an expenditure-switching device, but the fact that it also serves as a ‘conveyor belt’ transmitting costs into production structures and driving inflation quicker than the acclaimed price improvements undermines such merits.devaluation, inflation, stagnation, africa, imf
Food, faith and livelihoods : a case study of World Vision Malawi's food security programme in Chata ADP.
Masters Degree. University of KwaZulu-Natal, Pietermaritzburg.Abstract available in PDF.Not available for copying