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Renewable energy-powered membrane technology in Tanzanian communities
(Nature Research, 2018-12-03) Schäfer, Andrea; Shen, Junjie; Richards, Bryce
Dissolved contaminants such as ions or organic matter require advanced technology for effective removal. Technologies such as membrane processes are to date absent in remote areas of developing countries, in part due to the absence of a reliable electricity grid to power such technologies, but also due to the large distances to be served in remote areas. By directly coupling a nanofiltration system with solar energy, the energy provision and storage obstacle can be resolved. Here, two very challenging natural waters were treated to drinking water standard without requiring permanent infrastructure: both water samples had very high concentrations of fluoride (50–60 mg/L), while one of them also had a high total organic carbon content (255 mg/L). In both cases the WHO guideline value of 1.5 mg/L for fluoride was achieved with the chosen membrane. The solar irradiance provided an unsteady power source, which did not impact on water quality in a significant manner. Given the somewhat extreme characteristics of the source waters, making such waters potable effectively increased the available water quantity. The technical feasibility of such a solar-powered ultrafiltration and nanofiltration hybrid system was demonstrated in terms of produced drinking water quantity (1200 L per solar day), water quality and specific energy consumption. While such state-of-the-art technology offers great potential towards the provision of clean water in rural areas, the remaining obstacles for effective implementation of such technologies are predominantly non-technical.
Integrating insights from social-ecological interactions into sustainable land use change scenarios for small Islands in thewestern Indian ocean
(MDPI, 2020-02-12) Newman, Rebecca; Capitani, Claudia; Courtney-Mustaphi, Colin; Thorn, Jessica; Kariuki, Rebecca; Enns, Charis; Marchant, Robert
Small islands are vulnerable to the synergistic effects of climate change and anthropogenic disturbances due to the fact of their small area, geographical isolation, responsive ecologies, rapidly growing and developing populations and exposure to sea level and climate change. These changes exert pressures on ecosystem services, such as the provisioning of resources, and therefore threaten the sustainability of livelihoods. We reviewed key sustainability and livelihoods literature to bring together concepts of environmental livelihood resilience and stability across temporal and spatial scales and integrated them to produce a new conceptual framework for dynamic environmental livelihood sustainability (DESL). This framework aims to facilitate the incorporation of local community perspectives into water, energy and food nexus thinking about sustainable land use to support local livelihoods. Finally, we provide insights from this case study to evaluate the effectiveness of the DESL framework in addressing gaps in existing frameworks. We suggest this framing provides a mechanism for enhancing the agency of communities to produce more cohesive and inclusive land use management plans that can lead to enhanced environmental sustainability pathways.
Financial management practices and performance of agricultural small and medium enterprises in Tanzania
(Elsevier Ltd., 2023-03-29) Mang'ana, Kulwa; Ndyetabula, Daniel; Hokororo, Silver
Small and Medium-Sized Enterprises in agriculture sector, contribute significantly to economic change in developing countries by addressing a wide range of unemployment, nutrition, income poverty, and food security issues. Despite their critical role and contribution to economic growth, they have received a great deal of criticism for their poor performance. Most of the challenges confronting these agro-enterprises, however, are the result of poor financial management practices. Previous research studies have indicated generally that financial management practices have an impact on the performance and success for small businesses, yet scholarly research shows there is limited empirical evidence on which financial management practices have an influence on the agri-SMEs performance, which is why it was critical to examine this phenomenon. A total of 427 SMEs in Tanzania's agricultural sector were surveyed and examined. The developed hypotheses were evaluated using Structural Equation Modeling (SEM) with Smart PLS 4 to determine the effect of implementing financial management practices on the performance of agri-SME. Findings from the empirical study shows that working capital management practices and financing management practices have significant positive influence on both financial and organizational performance of the surveyed agro enterprises, while the accounting, financial reporting practices and capital budgeting management practices have insignificant influence on the performance agri-SMEs performance. Based on the findings, the study recommends that the government and regulatory authorities such as the Small Industries Development Organization (SIDO) must continue to emphasize their policies for improved agri-SME performance and sustainability while directly or indirectly encourage managers (venture owners) to consider working capital and financing practices as core to their financial management strategies.
Integrated Water Management in Mountain Communities: The Case of Feutap in the Municipality of Bangangté, Cameroon
(MDPI, 2023-04-09) Nya, Esther; Mwamila, Tulinave; Komguem-Poneabo, Lydie; Njomou-Ngounou, Emma; Fangang-Fanseu, Junior; Tchoumbe, Raoul; Tepong-Tsindé, Raoul; Gwenzi, Willis; Noubactep, Chicgoua
The whole population of Feutap still collects drinking water from two protected springs, some 1 km away from this small rural agglomeration. For many generations, the only improvement has been the protection of the springs during the 1980s. The resulting high incidence of gastrointestinal infections continues to hinder the socioeconomic development of this mountain community. This dynamic wherein “poverty begets disease, and disease begets poverty” seems endless given the number of water improvement programs and other health-focused campaigns in rural areas of Cameroon since the 1960s. Fortunately, the hydrographic regime of Feutap and its geographical situation enable the implementation of the Kilimanjaro Concept (KC), wherein rainwater is quantitatively harvested, partly infiltrated, and largely stored to (i) meet the whole-year water needs of the population, (ii) create new ecosystems, and (iii) enable irrigated agriculture. This communication prepares the implementation of the KC in Feutap, including the creation of irrigation ponds for agriculture and small farm animals (e.g., goats and sheep). The view is promoted that Feutap is a potential viable space in which life and work are possible, using the existing rainfall and the few natural springs in a sustainable manner. The presented concept can be extended to other hilly small communities with similar hydraulic regimes.
Metallic iron for decentralized safe drinking water supply: self-reliance is possible
(Elsevier, 2024-01-01) Noubactep, Chicgoua
Metallic iron (Fe0) is readily available worldwide and it has shown promise for water treatment in filtration systems. Fe0 filters remove physical contamination (e.g., colloids, suspended particles), pathogens (e.g., bacteria, viruses), and micropollutants (e.g., arsenic, nitrate, pesticides, and pharmaceuticals) from polluted waters. Accordingly, Fe0 filters can be used for water treatment applications where other materials (e.g., activated carbon, biochar, and bone char) are economically or logistically infeasible. Therefore Fe0 filters are a good candidate to help low-income communities in their efforts to achieve universal access to safe drinking water by 2030. The objective of this chapter was to summarize available knowledge on the design of Fe0 filters to booster their large-scale application at household and small community levels. Optimal conditions for Fe0 filters include the rational choice of the used materials building the reactive zone (Fe0 and other aggregates), the Fe0 ratio in the reactive zone, the Fe0 mass (e.g., size of the filter or number of filters in series), and the contact time (flow velocity). The proper combination of these design parameters is discussed. The results show that (1) all reactive Fe0 can be used for efficient water filters, (2) only porous Fe0 materials are suitable for sustainable water filters, (3) well-designed hybrid Fe0/aggregate systems are also sustainable, and (4) the major limitation of Fe0 filters is the lack of knowledge on the long-term corrosion rate. Future research efforts should last for months or years.