Breaking from the past? Environmental narratives, logics of power, and the (re)production of food insecurity in South Sudan.

Skyrocketing commodity prices and conflict-induced mass hunger in recent years have resuscitated discussions about why famines frequently reoccur in specific spaces of vulnerability. Intervention efforts still too often isolate food (in)security from its interwovenness in the political economy of water and energy and from the role of ideas in forging these interconnections across long time periods. Using (South) Sudanese history to rethink the causes of recurrent food insecurity, we underscore the need to analyse how political elites imagine the role of the water-energy-food nexus and associated environmental narratives in consolidating power. South Sudan's 2011 secession (from Sudan) marked the culmination of a struggle against a state that insurgents regarded as having starved its citizens. However, since independence, its leaders have replicated the nostrum they once combatted: Sudanese resources must 'feed the world'. A fixation with inserting water, energy, and food resources into global markets infuses their strategy, even if such an approach will not engender food abundance.

Synergistic evolution of water-energy-food system resilience and efficiency in urban agglomerations.

With increasing internal and external risks to the WEF system, a single emphasis on efficiency or a lopsided pursuit of resilience can lead to difficulties in adapting to complex changes and resource redundancy. Revealing the synergistic evolutionary characteristics between efficiency and resilience of the WEF system is an effective method to deal with systemic internal and external risks. However, the current study of the WEF system lacks a synergistic perspective on resilience and efficiency. Thus, taking Chengdu-Chongqing Economic Circle (CCEC) as the research object and its geospatial boundary as the system boundary, this paper adopted the entropy-topsis model to evaluate the WEF resilience, and applied the super-efficient SBM model to measure the WEF efficiency accurately, which fully considered the non-expected outputs in the process of resource utilization. Then, applying the development coordination degree model, the synergistic relationship between the two was measured. The results indicated that: the average value of WEF resilience in CCEC increased from 0.414 to 0.485 and showed spatial characteristics of west＞east＞central. The WEF efficiency interval was 0.79-0.93, and cities with average WEF efficiency reaching the effective production frontier accounted for only 37.5%. The clustered distribution of the synergy levels intensified. The number of cities with primary, medium, more advanced, and advanced levels was 6, 6, 1, and 3, respectively, with primary and medium synergy levels dominating. The findings suggest that cities should strengthen regional exchanges and formulate targeted measures based on their own situations. In addition, CCEC should possess a comprehensive understanding of the interdependencies and conflicts that arise between resilience and efficiency throughout the decision-making procedure.

A Systematic Review of Methodological Tools for Evaluating the Water, Energy, Food, and One Health Nexus in Transboundary Water Basins.

Water plays a vital role in human socioeconomic development and overall well-being, making its effective management essential in achieving the Sustainable Development Goals. The close interlinkage between water, other environmental resources, and socioeconomic development have prompted the emergence and adoption of holistic and trans-sectoral concepts such as integrated water resources management and, more recently, the resource nexus. However, even such holistic approaches often exclude the one health approach, particularly at the transboundary water basins (TWBs), which not only dominate 40% of the earth but are vital in environmental and human sustainability. This review aimed to understand, evaluate, and compare assessment tools for water, energy, food, and one health (WEF + H) nexus management in TWBs. The review applied the systematic review guidelines for articles published in the Scopus database. The inclusion criteria encompassed English-language articles featuring case studies, meta-studies, or review articles with no less than three nexus resources. The review categorized the article based on criteria that focused on identifying tools capable of analyzing scenarios and policies for WEF + H in TWBs and their accessibility and easiness of implementation in case studies. Of the eighteen analyzed tools, 13 (72%) had limitations in their application at various geographical scales. Additionally, they could not integrate one health into the nexus or analyze policies through running scenarios. On the contrary, the Bayesian networks, system dynamics, agent-based models, life-cycle assessments, and input-output tools were highly accessible for efficiently conducting scenario-based WEF + H nexus assessments in TWBs.

Woke Science and the 4th Industrial Revolution: Inside the Making of UNFSS Knowledge.

Understanding how science, technology, and innovation is produced by the UN Food Systems Summit process offers a lens into how dominant actors in global food policy continually rework their power and legitimacy. Focusing on discourses and material networks, the article shows that the Scientific Group makes appeals to inclusivity-of people of colour, women, youth, smallholders, and more-while extending old Green Revolution ideas through new 4th Industrial Revolution innovations and governance ambitions.

Innovating at the food, water, and energy interface.

Food, energy, and water (FEW) systems are inexorably linked. Earth's changing climate and increasing competition for finite land resources are creating and amplifying challenges at the FEW nexus. Managing FEW systems to mitigate these negative impacts and stresses is a pressing policy issue. The FEW interface is often managed as three independent systems, missing disruptive opportunities for streamlined integrated management. We contend that existing technologies can be reframed and emerging technologies can be harnessed for integrated FEW management, changing the way that each resource system operates within the broader system. We discuss solutions to three main challenges to integrating FEW system management: resolving spatiotemporal disconnections over multiple scales; closing resource loops; and creating actionable information. Sustainable resource management is critical for humanity, as well as for functioning trade systems and ecological health. Embracing integrated management in FEW systems would enable policy makers and managers to more efficiently and effectively secure critical resource systems in the face of global change.

Energising the WEF nexus to enhance sustainable development at local level.

The water-energy-food (WEF) nexus is increasingly recognised as a conceptual framework able to support the efficient implementation of the Sustainable Development Goals (SDGs). Despite growing attention paid to the WEF nexus, the role that renewable energies can play in addressing trade-offs and realising synergies has received limited attention. Until now, the focus of WEF nexus discussions and applications has mainly been on national or global levels, macro-level drivers, material flows and large infrastructure developments. This overlooks the fact that major nexus challenges are faced at local level. Aiming to address these knowledge gaps, the authors conduct a systematic analysis of the linkages between small-scale energy projects in developing countries and the food and water aspects of development. The analysis is based on empirical data from continuous process and impact evaluations complemented by secondary data and relevant literature. The study provides initial insights into how to identify interconnections and the potential benefits of integrating the nexus pillars into local level projects in the global south. The study identifies the complex links which exist between sustainable energy projects and the food and water sectors and highlights that these needs are currently not systematically integrated into project design or project evaluation. A more systematic approach, integrating the water and food pillars into energy planning at local level in the global south, is recommended to avoid trade-offs and enhance the development outcomes and impacts of energy projects.

Modelling the availability of water, energy, and food resources in transboundary river basins to achieve Sustainable Development Goals 2, 6, and 7.

The Water-Energy-Food Nexus (WEFN) has gained international attention as an approach for managing water more holistically, building on the progress made by the Integrated Water Resources Management (IWRM) approach. However, modelling the availability of water, energy, and food and their interconnections is complex, with major barriers that include the availability of both data and modelling platforms capable of assessing the interconnected systems of the WEFN. There have been attempts to model resource availability in each sector generally, but few attempts to consider the WEFN in complex transboundary basins, especially considering Sustainable Development Goals (SDGs). Here, a water, energy, and food availability model was developed using a combination of remotely sensed, national government reported, and global datasets. The model explores the complex interactions between the physical availability and production of water, energy, and food for several subbasins representing different states. Results showed the potential impacts of socioeconomic development, population changes and transboundary cooperation on resources. Transboundary cooperation in the case study Ma Basin in Southeast Asia, under existing resources and operations could improve monthly food security and reduce coal power operations using excess hydropower in the basin during the dry season. These findings show that transboundary cooperation improves access to energy and food, whilst potentially reducing demands for water. Furthermore, the research has highlighted ways in which transboundary cooperation can further assist in attaining SDGs 12 and 13 on responsible production and climate action, respectively. The modelling framework is easily transferable and can support similar analysis in other basins, contributing to global attainment of several SDGs.

Assessment of the water-energy-food nexus in the life cycle of energy products.

Given the urgent need to achieve energy security and transition from conventional to renewable energy sources, the energy sector is expanding rapidly. However, this growth often involves trade-offs with food and water resources. One way to address this complex interplay is to adopt the Water-Energy-Food nexus within a Life Cycle Assessment. This approach allows the analysis of interrelationships among the three sectors, aiming to foster synergies and minimize trade-offs. While numerous indicators exist to quantify the water-energy relationship, no similar approaches for the energy-food relationship could be found. To bridge this gap, in this paper, we introduce a novel indicator that measures the amount of food that could be produced causing the same land use impact in form of biodiversity damage as 1 MJ of the energy product. Together with another existing indicator that measures the water scarcity footprint per megajoule, a new framework for the analysis of the Water-Energy-Food (WEF) nexus of energy products is developed. Additionally, we present an optional net factor for both indicators. This factor helps to consider the energy use within the product's processes, contributing to a more comprehensive analysis. In our case study, we implement the outlined framework by examining biodiesel production in Argentina. We specifically analyze the impacts of two distinct agricultural technologies-Early and Late Soybean-on the Food and Water sectors. Our findings reveal that for every megajoule of the evaluated product, one could produce 62 or 93 kcal of food causing the same species loss. Additionally, the production process incurs a water scarcity footprint of 6.5 or 6.8 liters per megajoule, depending on the technology used. The proposed framework offers a means to mitigate the water and land use impacts associated with energy products. Consequently, it has the potential to enhance the WEF nexus.

Predictive simulation of the water-energy-food nexus for the City of Cape Town.

The City of Cape Town (CoCT), South Africa faced a critical situation between 2015 and 2018 in which the municipal water supply was almost completely exhausted. This situation, commonly referred to as Day Zero in South Africa emanated from a decline in rainfall, resulting in one of the most severe droughts in history. The crisis was also aggravated by rapid population growth and urbanization. CoCT was on the verge of becoming the first city in the past decade to experience a complete cessation of water supply for urban and agricultural purposes. In addition to the effects of low rainfall and population surge, urban energy consumption and increased food demand impacted directly the available water resources. To evaluate the interlinkages between water utilization, water production, energy supply and demand, and food production and demand, this study employed a system dynamics modeling (SDM) approach. The model was developed as a stock and flow diagram utilizing Stella Architect and encompassed five interconnected nodes: water, energy, food, land, and population. The findings revealed that by the end of the 20-year modeling period, the volume of accessible and stored water in all the major dams will be approximately 459 million cubic meters, with residential use accounting for about 85 % of urban water use and agriculture accounting for approximately30.37 % of total water demand. The model illustrates the impacts of precipitation rate, runoff, and evaporation on variables such as land-use change and population dynamics. It is anticipated that the outcomes of this study will serve as valuable inputs for decision-making processes, not only within the CoCT as it aims to mitigate or prevent the recurrence of Day Zero, but also for other cities facing similar challenges.

Coupling efficiency and spatial dynamic evolution of urban water-energy-food in China-A case of evidence from 94 cities.

Quantifying and interpreting the water-energy-food (WEF) nexus is critical to achieve the sustainable development of urban resources. The mismatch between urban water, energy and food allocations is a prominent problem that is particularly acute in the Yellow River Basin (YRB) of China. In this study, models for the WEF coupling degree and coupling efficiency were constructed. The WEF coupling efficiencies of the 94 cities in the YRB from 2011 to 2020 were quantified using a data envelopment analysis (DEA) model. On this basis, the spatial distribution characteristics and evolutionary trends of different urban WEF coupling efficiencies were analysed and explored using an exploratory spatial data analysis (ESDA) model and a parametric kernel density estimation model. The results show that the energy subsystem constrain the development of the WEF nexus, and the food subsystem, in turn, regulates the development of the WEF nexus. In some years, the phenomenon of 'resource curse' occurred, in which the WEF coupling degree increased while the coupling efficiency decreased. Overall, the values of the urban WEF coupling efficiency were low, ranging from 0.5300 to 0.6300, which is not effective. Spatial clustering was detected in the urban WEF coupling efficiency. The clustering types were 'high-high' clustering areas in less developed regions and 'low-low' clustering areas in developed regions. The two clusters and the median contiguous group had different evolutionary trends. Both efficiency and polarisation increased in the high-clustering group, efficiency improved in the low-clustering group, and a new efficiency pole was formed in the median contiguous group. Among the three grouped cities, we discuss the potential of policies such as cross-city cooperation, intra-city multi-sectoral cooperation and cultivating new central growth cities to improve the WEF coupling efficiency in the YRB.

A review of interconnected challenges in the water-energy-food nexus: Urban pollution perspective towards sustainable development.

The swift growth of cities worldwide poses significant challenges in ensuring a sufficient water, energy, and food supply. The Nexus has innovated valuable systems to address these challenges. However, a crucial issue is the potential for pollution resulting from these systems, which directly and indirectly impacts public health and the overall quality of urban living. This study comprehensively reviews the interconnected challenges of the water-energy-food (WEF) nexus and various forms of pollution in cities. The primary focus of this review article is to showcase the findings of WEF nexus studies regarding various pollutions across different geographical regions and spatial scales. It aims to examine the problems resulting from these pollutions, specifically their effects on human health and urban life. It also delves into the sources of pollution as identified in these studies. Furthermore, the article will highlight the proposed solutions from the research aimed at effectively mitigating pollution in each sector studied. This article is a systematic review which analyses research sources from the Scopus database. It extensively reviewed 2463 peer-reviewed published articles and focused explicitly on articles related to the WEF nexus that discussed pollution. Our study emphasizes, firstly, raising awareness about the crucial link between the WEF nexus, pollution, urban environments, and human health among policymakers and key stakeholders, including urban planners, industry partners and municipalities. This is to promote the development of policies that encourage sustainable practices and key stakeholders. Secondly, it evaluates WEF nexus and pollution research methods and findings, aiding in identifying research gaps technological innovation and potential, as well as enhancing decision-making. Lastly, it outlines future research challenges, providing a roadmap for researchers and policymakers to advance understanding in this domain and identify opportunities for resource efficiency and collaboration between different sectors.

A multivariate dataset on water-energy-food nexus: Multi-actor governance for social justice.

The article presents and validates an extensive multivariate dataset that offers insights into water-energy-food (WEF) nexus governance for social justice at the intrahousehold, household, and community levels. The lack of insights in the WEF nexus debate that take social justice and governance into account is what spurred the data collection. The initial process involved scoping the originally selected investigated sites and their suitability. Once the research areas were identified, the data were collected from 1184 households in the Matatiele, Magareng, and Greater Taung Local Municipalities in South Africa, using a semi-structured questionnaire and KoboCollect software. The freely available software was installed on Android Tablets which were used by the enumerators. The questionnaires were initially piloted in Matatiele Local Municipality, testing for internal validity and skip patterns, as well as time to complete the questionnaire. The reliability of the Likert responses from the questionnaire was evaluated using Cronbach's alpha. The questionnaire was then refined for data collection and utilized a total of twenty-two (22) locally trained enumerators who were employed at the investigated sites. These enumerators were trained in administering the questionnaire and the use of the KoboCollect software used in data collection. The enumerators also received training on how to conduct the survey ethically, including informed permission, confidentiality, and the option to withdraw from the interview. The design of the data collection process was a cross-sectional survey that was conducted between 6 June and 4 August 2022, using purposive sampling. At the end of each data collection day, the enumerators uploaded their collected data into the KoboTool cloud, which allowed the lead in the survey to assess the data and effect any correctional measures on the questionnaire if the need arose. The enumerators also used a WhatsApp chat group to communicate real time opportunities and challenges in the questionnaire, which allowed the lead in the survey to constantly update the questionnaire. The multivariate questionnaire was divided into sections of socioeconomic and demographic characteristics, community-level governance, decision-making, food, energy, and water security, social justice, legal knowledge, and rights to utilize these resources. The dataset will be of significance to multi-disciplinary researchers focusing on WEF security, governance, and social justice in Southern Africa. Furthermore, environmental and sustainability practitioners can find valuable insights from the provided data. The employed methodology is replicable and adaptable, enabling real-time monitoring of social justice and governance in the context of food, energy, and water security. The real time monitoring of governance and social justice in water, energy and food allows for the possibility of continual data collection and updating, and if a longitudinal design is adopted, it can be used for impact inquiry of any interventions or policies.

Water energy food nexus model: an integrated aqua-agriculture system to produce tilapia and sweet basil using desalinated water.

Under the framework of Water-Energy-Food Nexus, this study investigates the integration of solar-powered desalination with aquaculture and agriculture production systems to grow crops. Brackish water desalination is performed using reverse osmosis (RO), the permeate is directed to an aquaculture unit, and the fish effluent is used as irrigation water for crops. The experiment followed a split-plot design with three main variants: a full irrigation schedule for the basil plants with fish effluents as fertilizers, irrigation as fertigation with chemical fertilizers, and a mixed treatment of effluents and chemical fertilizers at 50% application each. Each treatment was further sprayed with or without foliar nutrient application. RO results gave a permeate recovery of 22%, and a salt rejection of 98.7%. In the aquaculture unit, tilapia harvest weight was 0.458 kg with a survival rate of 97.7% and harvest yield of 25 kg/ m3 of water. Effluent treatment exhibited the highest branching and plant height irrespective of the cut number, reaching 17.7 branches and 62-cm height. The effluent treatment under foliar application recorded the highest fresh and dry weights of basil with 14.7 ton/ha and 4.7 ton/ha, respectively. Effluent irrigation plus foliar application recorded basil yield of 5 kg/m3 effluent water. The dominant essential oil elements were linalool (55.5-61.6%), tau.-cadinol (5.3-8.3%), eucalyptol (5.4-7.7%), eugenol (2-6.8%), and (Z,E)-.alpha.-farnesene (3-5.2%). The study is among the very few integrated systems and, in particular, the current study is the first-time investigation of an integrated desalination, aquaculture, and agriculture production using renewable energy. Therefore, results suggest that integrating desalination, aquaculture, and agriculture could be a potential solution for the global water, energy, and food challenges.

Evaluation of water-energy-food-environment-agricultural economic growth nexus integrated approach to achieve sustainable production.

Today, growing the production of the agricultural sector in order to meet the increasing demand of food is happening through excessive consumption of water resources, energy, chemical fertilizers, and pesticides, especially in developing countries. Therefore, the present study aims to design a new approach for sustainable management of resources and realization of clean production in the agricultural sector. In order to design the new approach of the present study, the integration of two concepts of water-energy-food (WEF) nexus and decoupling pollution-agricultural growth (DEC) was used. The proposed approach is modeled through the multi-objective programming model by optimizing the WEF and DEC indices, which is the first research effort in this field. In this regard, the performance of this approach was evaluated in Jiroft County in Kerman province, Iran. The results of the study showed that the consumption of chemical fertilizers and pesticides in the optimal pattern with the simultaneous provision of WEF and gross margin (GM) goals (optimal 1) is about 110 kg and 0.19 l per hectare, respectively, more than the proposed pattern (optimal 3). On the other hand, the consumption of water and energy resources in the optimal pattern with the simultaneous provision of DEC and GM goals (optimal 2) is about 8785 cubic meters and 1108 MJ per hectare more than the proposed pattern (optimal 3), respectively. Therefore, this approach, due to the simultaneous integration of two concepts of sustainable development in the agricultural sector, can overcome the weakness of the WEF nexus in not paying attention to the issues of environmental pollution affected by the use of chemical inputs and the weakness of separating pollution-agricultural growth in not paying attention to the management of water and energy resources in the agricultural sector.

Development of WEF-P Nexus based on product-supply chain: A case study of phosphorous fertilizer industry in Morocco.

The aim of this study was to analyze various sustainability strategies for phosphate and phosphorous fertilizer production systems from the perspective of their holistic impacts on water, energy, and CO2 emissions. The study was conducted using the Water-Energy-Food (WEF) Nexus Tool 2.0, adapted to include the phosphate industry (WEF-P tool). It assesses the scenarios based on priorities identified by the Moroccan phosphate industry, such as the environmental impact of transporting phosphate rock by train and phosphate slurry by pipeline and increased desalinated water use. Results show that each scenario's sustainability can be assessed in terms of phosphate production, processes, resource (water and energy) availability, and CO2 emissions in mining and manufacturing areas. The analytical methodology of the tool is based on an integrated supply chain and life cycle assessment, which includes the production flows linking mining phosphate and manufacturing phosphorous fertilizers and their water and energy supply systems. Field surveys were used to identify the supply chain and estimate the relationships between production and resource consumption in each process. The tool is a decision-support platform that produces sustainability indices for multiple scenarios of resource allocation (water and energy) and CO2 emissions, allowing stakeholders to compare potential outcomes and formulate decisions based on their understanding of the actual trade-offs involved.

A Comprehensive Evaluation Framework of Water-Energy-Food System Coupling Coordination in the Yellow River Basin, China.

For mankind's survival and development, water, energy, and food (WEF) are essential material guarantees. In China, however, the spatial distribution of WEF is seriously unbalanced and mismatched. Here, a collaborative governance mechanism that aims at nexus security needs to be urgently established. In this paper, the Yellow River Basin in China with a representative WEF system, was selected as a case. Firstly, a comprehensive framework for WEF coupling coordination was constructed, and the relationship and mechanism between them were analyzed theoretically. Then, we investigated the spatiotemporal characteristics and driving mechanisms of the coupling coordination degree (CCD) with a composite evaluation method, coupling coordination degree model, spatial statistical analysis, and multiscale geographic weighted regression. Finally, policy implications were discussed to promote the coordinated development of the WEF system. The results showed that: 1) WEF subsystems showed a significant imbalance of spatial pattern and diversity in temporal changes; 2) the CCD for the WEF system varied little and remained at moderate coordination. Areas with moderate coordination have increased, while areas with superior coordination and mild disorder have decreased. In addition, the spatial clustering phenomenon of the CCD was significant and showed obvious characteristics of polarization; and 3) the action of each factor is self-differentiated and regionally variable. For different factors, GDP per capita was of particular importance, which contributed most to the regional development's coupling coordination. For different regions, GDP per capita, average yearly precipitation, population density, and urbanization rate exhibited differences in geographical gradients in an east-west direction. The conclusion can provide references for regional resource allocation and sustainable development by enhancing WEF system utilization efficiency.

A copula-based security risk evaluation and probability calculation for water-energy-food nexus.

Water-energy-food (WEF) are essential for human survival and development and they interact complexly. The research on Water-energy-food-coupling security risk (WEF-CSR) is crucial to promoting multi resource collaborative management. In this study, a comprehensive index system was constructed using three dimensions: reliability (Ra), coordination (C), and resilience (Rs). We selected the middle and upper reaches of the Yellow River Basin in China to study WEF-CSR conflicts, coupled with the Copula method of risk probability calculation. The results showed that: 1) from 2005 to 2021, the WEF-CSR index in the study area showed a progressively increasing trend, with a mean value of 0.49 in a critical safety state and lower values in the upper reaches of Ningxia and Gansu provinces. 2) The Ra-indexes in the criterion layer is not clearly affected by resource endowment conditions between annual periods; C-indexes are growing rapidly, with their annual growth rate four times as fast as the Ra-indexes, and Rs-indexes growing at about 2.7 times faster. 3) "Energy consumption per capita, carbon emissions, and water-related indicators" are the six main limiting factors, with a combined impediment degree of over 35 %, water resources are major constraint. 4) The Ra-C, C-Rs, and Ra-C-Rs indexes are well fitted by Clayton copula, and the C-Rs indexes are well fitted by Frank copula. The three-dimensional joint distribution risk probability, Ra-C-Rs (Ra ≤ 0.4, C ≤ 0.4, Rs ≤ 0.4) is 0.29. When the Ra or C indexes increases, the probability of unsafe Rs rises to 40 %-50 %, meaning future development must emphasize synergy, especially in Rs. In future, the five provinces in the middle and upper reaches of the Yellow River should focus on reducing energy pressure, improving water shortage conditions, and enhancing the overall resilience to avoid single-factor adverse conditions affecting WEF's coordinated and sustainable development.

Characteristics, regional differences, and influencing factors of China's water-energy-food (W-E-F) pressure: evidence from Dagum Gini coefficient decomposition and PGTWR model.

Water, energy, and food security are global concerning issues especially in China. To promote regional environmental management cooperation as well as find resource security influencing factor differences among regions, this paper calculates the water-energy-food (W-E-F) pressure, find W-E-F pressure's regional differences, and the influencing factors by Dagum Gini coefficient decomposition and geographically and temporally weighted regression model for panel data (PGTWR). First, the temporal trend of W-E-F pressure is decreasing and then increasing during 2003-2019; pressure in the eastern provinces is significantly higher than in other provinces and structurally energy pressure is the dominant resource pressure in W-E-F in most provinces. Besides, inter-regional differences are the main source of regional differences in China's W-E-F pressure, particularly for the inter-regional differences between eastern regions and other regions. In addition, there are obvious spatio-temporal heterogeneity effects of population density, per capita GDP, urbanization, energy intensity, effective irrigated area, and forest cover on W-E-F pressure. Balancing regional development gaps and developing differentiated resource pressure mitigation strategies based on the characteristics of different regional drivers are of great importance.

Environmental assessment of on-site source-separated wastewater treatment and reuse systems for resource recovery in a sustainable sanitation view.

Sustainable sanitation solutions are necessary for promoting public health and environmental security. In this study, on-site domestic wastewater treatment (WWT) systems used for households in rural and peri-urban areas of Brazil were compared in different scenarios from a life cycle assessment (LCA) perspective. The evaluated scenarios represented different practices in wastewater management, such as direct discharge into the soil, rudimentary treatment, septic tank, public sewerage system, and source separation of wastewater streams for water, nutrient, and organic matter recovery. The WWT technologies considered in the proposed scenarios of source-separated wastewater streams were as follows: an evapotranspiration tank (TEvap) and composting toilet for blackwater, a modified constructed wetland (EvaTAC) for greywater, and a storage tank for urine. LCA was performed in this study according to the ISO standards to assess the environmental impacts at both midpoint and endpoint levels. The results show that on-site source-separated wastewater treatment systems with resource recovery result in significant reductions in environmental impacts compared to scenarios with precarious conditions or 'end-of-pipe' solutions. For example, regarding the human health damage category, the scenarios involving resource recovery, including systems such as EvaTAC, TEvap, composting toilet, and urine storage tank, demonstrate significantly lower values (-0.0117 to -0.0115 DALY) compared to scenarios with rudimentary cesspits and septic tanks (0.0003 to 0.001 DALY). We conclude that the focus should be beyond mere pollution aspects and instead concentrate on the benefits of the co-products, which are: avoiding the extraction and consumption of valuable and increasingly scarce raw materials, such as potable water, and production of synthetic fertilizer. Furthermore, it is highly recommended that an LCA of sanitation systems synergistically integrates the WWT process, the constructive aspects, and the resource recovery potential.

Input-Output Efficiency of Water-Energy-Food and Its Driving Forces: Spatial-Temporal Heterogeneity of Yangtze River Economic Belt, China.

The high-quality development of the Yangtze River Economic Belt (YREB) plays a crucial role in economic transformation in China. Climate change, rapid population growth, and increased urbanization have contributed towards increased pressures on the water, energy, food (WEF) nexus system of YREB. Thus, there is an imperative need to improve the efficiency of WEF in YREB. However, few studies have conducted spatial-temporal heterogeneity exploration of YREB about the input-output efficiency of WEF (IOE-WEF). Using panel data from 2008-2017, a super slack based model (SSBM), combined with the spatial autocorrelation and spatial econometric method, were proposed to calculate the IOE-WEF of YREB's 11 provinces, the results indicated that: (1) From the perspective of time, the IOE-WEF in YREB was relatively low and displayed a fluctuating downward pattern while considering the undesirable outputs. (2) From the perspective of space, the spatial distribution of IOE-WEF in YREB was uneven. The efficiency values of the three sub-regions of YREB were "the lower reaches > the middle reaches > the upper reaches". The IOE-WEF of YREB had a prominent positive spatial correlation and also had a spatial spillover effect. (3) The spatial aggregation effect of IOE-WEF of YREB is gradually weakening. The spatial aggregation types of IOE-WEF in YREB were "high-high" cluster areas in lower reaches and "low-low" cluster areas in upper reaches. (4) From the perspective of driving forces, environmental regulation and technological innovation promoted the improvement of IOE-WEF of YREB, while the industrial structure and mechanization level inhibited the improvement of IOE-WEF of YREB. Furthermore, the role of government support of IOE-WEF of YREB was not obvious. The improvement of IOE-WEF in adjacent regions also had a notable positive spatial spillover effect on the region.