The chemistry, antimicrobial efficacy and energy consumption of plasma-activated water (PAW) was optimized by altering the discharge frequency, ground-electrode configuration, gas flow rate and initial water conductivity for two reactor configurations, i.e., air pin-to-liquid discharge and air plasma-bubble discharge in water. The ratio of NO₂⁻ and NO₃⁻ formation was altered to optimise the antimicrobial effects of PAW, tested against two Gram-negative bacteria. An initial solution conductivity of 0.2 S·m⁻¹ and 2000-Hz discharge frequency with the ground electrode positioned inside the pin reactor showed the highest antimicrobial effect resulting in a 3.99 ± 0.13-log₁₀ reduction within 300 s against Escherichia coli and 5.90 ± 0.24-log₁₀ reduction within 240 s for Salmonella Typhimurium. An excellent energy efficiency of reactive oxygen and nitrogen species (RONS) generation of 10.1 ± 0.1 g·kW⁻¹·h⁻¹ was achieved.Plasma-activated water (PAW) is deemed as an eco-friendly alternative to chemical disinfection because its bactericidal activity is temporary. Optimizing the design and operation of PAW reactors to achieve high inactivation rates of more than 5-log₁₀ reductions, as demonstrated in this work, will support the industrial application of this technology and the scaleup at industrial level.

Green roofs are strategic tools that can play a significant role in the creation of sustainable and resilient cities. They have been largely investigated thanks to their high retention capacity, which can be a valid support to mitigate the pluvial flood risk and to increase the building thermal insulation, ensuring energy saving. Moreover, green roofs contribute to restoring vegetation in the urban environment, increasing the biodiversity and adding aesthetic value to the city. The new generation of multilayer green roofs present an additional layer with respect to traditional ones, which allows rainwater to be stored, which, if properly treated, can be reused for different purposes. This paper offers a review of benefits and limitations of green roofs, with a focus on multilayer ones, within a Water-Energy-Food-Ecosystem nexus context. This approach enables the potential impact of green roofs on the different sectors to be highlighted, investigating also the interactions and interconnections among the fields. Moreover, the Water-Energy-Food-Ecosystem nexus approach highlights how the installation of traditional and multilayer green roofs in urban areas contributes to the Development Goals defined by the 2030 Sustainable Agenda.

The objective of this study was evaluate the efficiency in water and food use in sheep production, using two new traits (residual water intake - RWI; residual feed and residual water intake - RFRWI). For this purpose, we evaluated the relationships between the traits total water intake, RWI and RFRWI with water measures, productive performance and carcass traits (ultrasound). We used 32 lambs with age of 3 months: 16 Santa Ines breed (8 males and 8 females) and 16 crossbred 7/8 Dorper x Santa Ines (8 males and 8 females). They were fed at an automated feed and water station (Intergado®), where the food and water intake by each animal was measured automatically. Residual water intake (RWI), residual feed intake (RFI) and residual body weight gain (RWG) were calculated using the MIXED procedure in SAS®. Correlation coefficients between total water intake (TWI), RWI and all traits (water measures, performance and carcass traits) were calculated using the CORR procedure (P ≤ 0.05). Total water intake showed mean 3.15 L/day during the study and the RWI ranged from 0.66 L to -0.89 L, which represents a difference of 1.55 L between the most and least efficient animal. There was positive correlation between less efficient animals in water consumption (positive RWI) and water intake (r = 0.31); total water intake in relation to dry matter intake (r = 0.36); total water intake in relation to mid-trial metabolic body weight (r = 0.26); residual feed and residual water intake (r = 0.99) and gain/feed ratio (r = 0.44). There was negative correlation between less efficient animal and dry matter intake in relation to body weight (r= -0.33) and feed conversion ratio (r= -0.44). The evaluation of the new variables, RWI and RFRWI, proved effective in identifying the most efficient animals in water use. Moreover, these findings open the possibility of considering the traits RWI and RFRWI in sheep selection, because performance and carcass traits are not adversely affected by selecting for these new traits.

In this paper we analyze the relationship between social inequality and climate change policy actions in African countries. We examine whether the needs of the poor influence mitigation and adaptation policies in the region. The continent is characterized by an interesting dynamic between inequality and climate change: it is predicted to disproportionately bear the effects of climate change, at the same time that it accounts for four out of the top five countries with the starkest inequality globally. In our analysis, we construct a statistical measure of social inequality for a group of 54 African countries and use the Intended Nationally Determined Contributions (INDCs) to obtain corresponding data on mitigation and adaptation policy actions. We then estimate the intensity of the responsiveness of the latter to the former. Using fractional regression and data imputation methods, we find a statistically significant negative relationship between social inequality and climate change policy actions in Africa. Across African countries, mitigation and adaptation actions fall by about 23% for every 1% rise in social inequality. African countries are therefore not responding to climate change threats in ways that simultaneously reduce social inequality and adapt to climate change. Furthermore, there is some evidence that countries emitting more pollutants are less likely to take action to address climate change. Our results imply that in order to address differences in the burden of climate change in Africa, a re-evaluation of current policy actions is warranted.

The notion of a water–energy–food (WEF) nexus was introduced to encourage a more holistic perspective on the sustainable development of natural resources. Most attention has been directed at identifying potential synergies and trade-offs among sectors that could be addressed with improved technologies and management. The governance of the WEF nexus more broadly has received comparatively little attention, and the importance of scale in space and time has been largely ignored. Inspired by scholarship on multi-level governance in individual sectors, this paper identifies four scale-related governance challenges in the WEF nexus, namely: (1) scalar fit, which arises when planning and operating procedures work at different levels along the scales of space and time in different sectors; (2) scalar strategies, wherever the levels at which actors have influence and in which action takes place are contested and negotiated; (3) institutional interplay, where rules and norms in different sectors influence each other at different levels; (4) scalar uncertainty, arising out of the complexity of multi-level and multi-scale interactions. The relevance of these four challenges is illustrated with case studies from developed and developing countries. These examples show the importance of considering multiple levels and scales when assessing the likely effectiveness of WEF nexus governance mechanisms or proposals. The cases underline the need to pay close attention to issues of power, contestation, and negotiation, in addition to the analysis of institutional design. Thus, this paper recommends that nexus governance efforts and proposals be scrutinized for scale assumptions. The four identified challenges offer a suitable starting point for diagnosis.

Microorganism assessment plays a key role in food quality and safety control but conventional techniques are costly and/or time consuming. Alternatively, electronic tongues (E-tongues) can fulfill this critical task. Thus, a potentiometric lab-made E-tongue (40 lipid sensor membranes) was used to differentiate four common food contamination bacteria, including two Gram positive (<i>Enterococcus faecalis</i>, <i>Staphylococcus aureus</i>) and two Gram negative (<i>Escherichia coli</i>, <i>Pseudomonas aeruginosa</i>). Principal component analysis and a linear discriminant analysis-simulated annealing algorithm (LDA-SA) showed that the potentiometric signal profiles acquired during the analysis of aqueous solutions containing known amounts of each studied bacteria allowed a satisfactory differentiation of the four bacterial strains. An E-tongue-LDA-SA model (12 non-redundant sensors) correctly classified 98 ± 5% of the samples (repeated K-fold-CV), the satisfactory performance of which can be attributed to the capability of the lipid membranes to establish electrostatic interactions/hydrogen bonds with hydroxyl, amine and/or carbonyl groups, which are comprised in the bacteria outer membranes. Furthermore, multiple linear regression models, based on selected subsets of E-tongue sensors (12–15 sensors), also allowed quantifying the bacteria contents in aqueous solutions (0.993 ± 0.011 ≤ <i>R</i>² ≤ 0.998 ± 0.005, for repeated K-fold-CV). In conclusion, the E-tongue could be of great value as a preliminary food quality and safety diagnosis tool.

Extant studies address water, food, and health security issues considerably separately and within narrow disciplinary confines. This study investigates the links among these three issues from an ecological viewpoint with a multidisciplinary approach in a modified Millennium Ecosystem Assessment framework developed by the United Nations. The modified framework includes water, food, and health security considerations as the three constituents of human well-being from an ecological (more specifically, ecosystem services) viewpoint. This study examines the links through published data associated with the Minamata incident, which was a historic and horrific methylmercury-induced water, food, and health poisoning crisis in Japan. The results show that when heavy metal pollution changes one component (marine water) of the provisioning ecosystem services, this change subsequently affects another component (seafood) of the services. This then defines the linkages among water, food, and health security as the three constituents of human well-being within the modified framework. The links can have immediate and far-reaching economic, social, legal, ethical, and justice implications within and across generations. This study provides important evidence for emerging economies that ignore the water–food–health security nexus.

Ending hunger and ensuring food security are among targets of 2030 s SDGs. While food trade and the embedded (virtual) water (VW) may improve food availability and accessibility for more people all year round, the sustainability and efficiency of food and VW trade needs to be revisited. In this research, we assess the sustainability and efficiency of food and VW trades under two food security scenarios for Iran, a country suffering from an escalating water crisis. These scenarios are (1) Individual Crop Food Security (ICFS), which restricts calorie fulfillment from individual crops and (2) Crop Category Food Security (CCFS), which promotes eating local by suggesting food substitution within the crop category. To this end, we simulate the water footprint and VW trades of 27 major crops, within 8 crop categories, in 30 provinces of Iran (2005 2015). We investigate the impacts of these two scenarios on (a) provincial food security (FSp) and exports; (b) sustainable and efficient blue water consumption, and (c) blue VW export. We then test the correlation between agro-economic and socio-environmental indicators and provincial food security. Our results show that most provinces were threatened by unsustainable and inefficient blue water consumption for crop production, particularly in the summertime. This water mismanagement results in 14.41 and 8.45 billion m3 y-1 unsustainable and inefficient blue VW exports under ICFS. Eating local improves the FSp value by up to 210% which lessens the unsustainable and inefficient blue VW export from hotspots. As illustrated in the graphical abstract, the FSp value strongly correlates with different agro-economic and socio-environmental indicators, but in different ways. Our findings promote eating local besides improving agro-economic and socio-environmental conditions to take transformative steps toward eradicating food insecurity not only in Iran but also in other countries facing water limitations. © 2021, The Author(s). | We would like to thank the reviewers of the manuscript for their constructive comments. Thanks to Ms. Manuela Rosso—Brugnach for proofreading the article. This Project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Earth@lternatives Project, Grant agreement No 834716). Brugnach is supported by the Spanish Government through María de Maeztu excellence accreditation 2018–2022 (Ref. MDM-2017-0714) of BC3.

Pseudomonas aeruginosa (P. aeruginosa) is the common infection-causing bacterial pathogen. Conventional methods for the detection of P. aeruginosa are time-consuming, and therefore, a more rapid analytical method is required. Here, monoclonal antibodies (Mabs) against P. aeruginosa (CICC 10419) were prepared and based on paired Mabs, an immunochromatographic assay (ICA) was developed. The ICA strip showed a limit of detection of 2.41 × 104 CFU/mL and the linear range of detection was 3.13 × 104-1.0 × 106 CFU/mL. No cross-reactivity was observed when other common Gram-negative and Gram-positive bacteria were used. The analytical performance of the ICA strip indicated that the developed ICA had good specificity and stability. Moreover, the feasibility of the ICA strip was verified by detecting P. aeruginosa (CICC 10419) in spiked water and food samples. The ICA strip could detect samples contaminated with a low-level of P. aeruginosa (CICC 10419) after 8 h enrichment.

The challenges posed by the water–food–energy nexus have been well documented. Demand for all three of these crucial elements of human growth is increasing, driven by a rising global population, rapid urbanization, changing diets, and economic growth. However, an integrated approach to technological, institutional, and policy innovation is missing in the context of achieving the Sustainable Development Goals (SDGs). The proposed strategy in this policy brief relies on three pillars: (1) improvements in the measurement and promotion of better policies and investments for integrated energy, water, and food security; (2) the assessment of the institutional constraints and determinants of the inequalities between leading and lagging countries and the speed of adjustment that will bring convergence among them; and (3) the facilitation of renewable energy technologies as an environmentally sustainable supply of energy, with substantial positive spill-over effects in the water and food sectors. The suggestion is to promote policies to (1) facilitate which determinants are best suited to enhance the convergence of policy process, such as economic diversification, subsidy removal, and liberalization through a multisectoral approach; and (2) support increasing electricity access using alternative sources of energies in remote rural areas in Asia, Africa, and Latin America through integrated Official Development Assistance (ODA) and Foreign Direct Investment (FDI). | Non-PR | IFPRI5 | DSGD