This study assessed fluoride levels in domestic water, commonly consumed food crops, cow’s, and human milk. Samples of vegetables were collected from farmer’s home gardens, green banana from local markets, maize flour, and domestic water from households, while cow’s and human (breast) milk were obtained from cows and lactating mothers. Fluoride levels were determined by using a fluoride ion-selective electrode. Fluoride levels were 0.03 ± 0.02 mg/kg in maize, In leafy vegetables the highest levels were found in nightshade 0.081 ± 0.008 mg/kg, while for banana varieties the highest levels were found in in East African highland 0.025 ± 0.004 mg/kg. Levels in cows and human breast milk were 0.34 ± 0.2 mg/L and 0.077 ± 0.06 mg/L, respectively. Levels in domestic and public tap water were 4.57 ± 0.4 mg/L and 4.74 ± 0.8 mg/L, respectively. Study provided useful knowledge of fluoride levels in several crops, milk, and domestic water.

With adverse impacts of climate change growing in number and intensity, there is an urgent need to reduce emissions from food systems to net zero. This can only be achieved if rural areas in low- and middle-income countries gain access to clean energy. A review of the research and capacity building contributions of the CGIAR Research Program on Water, Land and Ecosystems (WLE) over the last 10 years suggests important contributions in the areas of energy policy and energy investment planning, cost and feasibility frameworks, and business models for clean energy technology uptake. WLE has also conducted successful pilot projects on solar irrigation to provide an evidence base for scaling up innovative energy initiatives. Finally, the program also considered non-agricultural uses of energy where relevant to food systems, and implemented capacity building activities. Going forward, CGIAR has a key role to play in providing information, supporting access and piloting innovative, scalable clean energy interventions to support the achievement of multiple impacts for the poorest and most food-insecure women and men farmers and entrepreneurs. | Non-PR | IFPRI5; CRP5 | EPTD | CGIAR Research Program on Water, Land and Ecosystems (WLE)

With adverse impacts of climate change growing in number and intensity, there is an urgent need to reduce emissions from food systems to net zero. This can only be achieved if rural areas in low- and middle-income countries gain access to clean energy. A review of the research and capacity building contributions of the CGIAR Research Program on Water, Land and Ecosystems (WLE) over the last 10 years suggests important contributions in the areas of energy policy and energy investment planning, cost and feasibility frameworks, and business models for clean energy technology uptake. WLE has also conducted successful pilot projects on solar irrigation to provide an evidence base for scaling up innovative energy initiatives. Finally, the program also considered non-agricultural uses of energy where relevant to food systems, and implemented capacity building activities. Going forward, CGIAR has a key role to play in providing information, supporting access and piloting innovative, scalable clean energy interventions to support the achievement of multiple impacts for the poorest and most food-insecure women and men farmers and entrepreneurs.

The impact of human activities and climate change occurs across a range of spatial and temporal scales, and the city or regional scale is critical for managing food–energy–water (FEW) resources. We develop a coupled human-natural system model for Cape Town, South Africa, which consists of an agent-based model and a regional hydrologic model, to study the FEW nexus connecting the agricultural, urban, and hydroelectric generation sectors. We use the model to compare three policies—a simple adaptive approach, adaptation with free water to indigent households, and water supply augmentation—and assess their ability to provide reliable FEW services to the different stakeholders under four different climate scenarios, representing moderate to severe amounts of warming. Our results indicate that Cape Town is likely to face increasing water stress as temperatures rise, and that adaptation strategies could effectively mitigate the effects of water limitations and avoid severe failures in providing FEW services across sectors. One way to manage demand for FEW services is by adjusting water price tariffs, but high prices create inequality in access to water for households with different incomes. Our analysis suggests that the water supply system in Cape Town may already be at, if not over, its sustainable capacity within the FEW nexus. Our model serves as a test-bed for assessing policies to manage stresses on water resources for the benefit of stakeholders across FEW sectors. This model can be adapted to cities and regions around the globe.

A bi-level decentralized chance-constrained programming (BDCP) method is developed for planning water-food-ecology-energy (WFEE) nexus system. The BDCP method has advantages in balancing the tradeoff between two-level stakeholders in hierarchical structure and reflecting the synergy effect among multiple divisions under random uncertainty. Then, a BDCP-WFEE model is formulated for the Aral Sea Basin, where the upper-level model aims to maximize system benefit, and the multiple divisions at the lower-level model aim to maximize food production, ecological water allocation, and electricity generation. Compared with the conventional single-level model, results obtained from the BDCP-WFEE model under multiple scenarios reveal that (i) the food production would increase by 2.0%–3.6% , implying that the food demand of additional 0.7 million people can be met; (ii) the ecological water allocation would increase by 0.9%–3.0%, denoting that the amount of water to the Aral Sea would reach 23.4 km³ at the end of planning period; (iii) the electricity generation would increase by 5.4%–8.5%. Besides, under the premise of ensuring food security, the proportion of agricultural water allocation in the Aral Sea Basin would reduce by 17.0%, indicating that the BDCP-WFEE model can effectively optimize the water allocation pattern and alleviate the conflict of water resources allocation among competetive users. These findings can provide policy support for managers to solve the problems of water shortage, food crisis, ecological degradation, and electricity insecurity.

Supercritical water gasification (SCWG) can efficiently convert food waste to hydrogen-rich syngas without pre-dewatering. NaCl salt is the most common food additive and therefore inevitably accumulated in food waste. Though, the role of NaCl in SCWG of food waste is still unexplored. In this study, the influences of NaCl salt in food waste during SCWG on syngas production and corrosion of reactor material were investigated. The model food waste, representing food waste in China, with different NaCl contents (0–6 wt% dry basis) was gasified in supercritical water at 500 °C and autogenous pressure of ca. 28 MPa. The highest total gas yield of 21.70 mol/kg and H₂ yield of 6.89 mol/kg were obtained in the case of 3 wt% NaCl. The corrosion test on Hastelloy C276 and stainless steel SS316L materials was conducted in supercritical water for 24 h with different NaCl concentrations. Hastelloy C276 showed better resistance to corrosion in supercritical water than stainless steel 316L. However, when NaCl was involved in the reaction, large oxides grains of NiFe₂O₄, FeCr₂O₄, NiO, and Fe₃O₄ were observed on the surface of both materials.

Effects of a changing climate on agricultural system productivity are poorly understood, and likely to be met with as yet undefined agricultural adaptations by farmers and associated business and governmental entities. The continued vitality of agricultural systems depends on economic conditions that support farmers’ livelihoods. Exploring the long-term effects of adaptations requires modeling agricultural and economic conditions to engage stakeholders upon whom the burden of any adaptation will rest. Here, we use a new freeware model FEWCalc (Food-Energy-Water Calculator) to project farm incomes based on climate, crop selection, irrigation practices, water availability, and economic adaptation of adding renewable energy production. Thus, FEWCalc addresses United Nations Global Sustainability Goals No Hunger and Affordable and Clean Energy. Here, future climate scenario impacts on crop production and farm incomes are simulated when current agricultural practices continue so that no agricultural adaptations are enabled. The model Decision Support System for Agrotechnology Transfer (DSSAT) with added arid-region dynamics is used to simulate agricultural dynamics. Demonstrations at a site in the midwest USA with 2008–2017 historical data and two 2018–2098 RCP climate scenarios provide an initial quantification of increased agricultural challenges under climate change, such as reduced crop yields and increased financial losses. Results show how this finding is largely driven by increasing temperatures and changed distribution of precipitation throughout the year. Without effective technological advances and operational and policy changes, the simulations show how rural areas could increasingly depend economically on local renewable energy, while agricultural production from arid regions declines by 50% or more.

Understanding the interconnections and tradeoffs between food, energy, and water (FEW) in grain production, which are essential for agricultural sustainability, remains an elusive yet important task. We propose a four-step analysis method for exploring potential approaches to coordinating the FEW nexus in grain production based on a conceptual framework that incorporates the impact of rural livelihood transitions and farmland resource constraints. We apply this method to a small-scale watershed in Hunan Province, China using data from land-use maps, farm household surveys, farmland quality surveys, and cropping-pattern surveys. Transitions of rural livelihoods have led farmlands to become increasingly large in scale. The combined impacts of this concentration of large-scale farms and the government subsidy policy, which favors double cropping, undermines the FEW nexus. Our findings suggest two operational approaches for coordinating the FEW nexus in rice production. One is to develop adaptive agricultural policies that support farmers whose aggregate performance on rice production is superior or more balanced. The other is to optimize cropping patterns based on the suitability of farmland for grain planting.