The study objective was to develop and use the Water-Energy-Food Nexus Phosphate (WEF-P) Tool to evaluate the impact of Morocco's phosphate industry on water, energy, and food sectors of Khouribga, which is the representative phosphate mining region of Morocco. The developed WEF-P Tool enabled a trade-off analysis based on integrating supply-chain processes, transportation, and water- energy footprints of the region. Field data from the mining to transportation processes were collected and applied to possible supply-chain scenarios in accordance with the type of product (phosphate rock and slurry). The potential impacts of the scenarios were considered in terms of the water supply in the agricultural areas. The analysis of the positive impacts of dynamic management suggests that seasonal management of phosphate production (less during the irrigated season, more during wetter or rainier seasons) is more effective. Additionally, while the transport of raw phosphate slurry through a pipeline increased the total water required to 34:6-106 m3, which is an increase of 76% over the business as usual (BAU) scenario, it also resulted in an energy savings of nearly 80% over BAU: slurry transport requires only 40:5-106 L of fossil fuel instead of the 204-106 L required to transport rocks. During the dry or water-scarce irrigation season (May to July), total groundwater use decreased from 5:8-106 to 5:2-106 m3. Dynamic management of the phosphate industry can also save 143MWh (megawatt-hour) of electricity annually and can bring a reduction of 117 t of CO2 emissions. Making water available at the correct season and location requires analysis of complex scientific, technical, socioeconomic, regulatory, and political issues. The WEF-P Tool can assist by assessing user-created scenarios; thus, it is an effective management-decision aid for ensuring more sustainable use of limited resources and increased reliability of water resources for both agricultural and industrial use. This study on the applications of WEF Nexus to the phosphate industry offers a roadmap for other industrial application for which trade-offs between the primary resources must be considered. © 2020 Copernicus GmbH. All rights reserved.

Abstract While agricultural activities are a major drain on water resources in Rwanda, its high population growth continually escalates energy–water–food–land nexus pressures. With 13.03 million inhabitants on a 26,336 km2 area which translates to be 495 inhabitants per km2, Rwanda has the second‐highest population density in Africa because of its high annual population growth rate of 2.95%. Access to clean drinking water, energy, and food to meet the demographic needs in Rwanda are fundamental, but this is unlikely to be the case by 2050 due to the anticipated land scarcity. Land stress is endangering energy, water, and food security, and this works against ecological sustainable development. This research analyzed the ecological balance of human activities in Rwanda and how policymakers have increasingly emphasized on energy–water–food nexus sectors separately without integrating land usage and population growth which poses an even more critical situation if left unattended to. The research study recommends the Multi‐Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) method as being appropriate to support the transition toward a sustainable economy because it is used to optimize resources, generate focused decisions, actions, investments, and policies that would combat nexus pressures and promote ecological sustainable development.

The winter wheat–summer maize double cropping system caused overexploitation of groundwater in the North China Plain; it is unsustainable and threatens food security and the overall wellbeing of humankind in the region. Finding water-saving cropping systems without compromising food security is a more likely solution. In this study, six alternative cropping systems’ water conservation and food supply capacity were compared simultaneously. A combined water footprint method was applied to analyze the cropping systems’ water consumption. The winter wheat–summer maize system had the largest water consumption (16,585 m³/ha on average), followed by the potato/spring maize, spinach–spring maize, rye–spring maize, vetch–spring maize, pea/spring maize, soybean||spring maize and mono-spring maize cropping systems. For the groundwater, the spinach–spring maize, pea/spring maize, soybean||spring maize systems showed a higher degree of synchronization between crop growth period and rainfall, which could reduce use of groundwater by 36.8%, 54.4% and 57.6%, respectively. For food supply capacity, the values for spinach–spring maize, pea/spring maize, soybean||spring maize systems were 73.0%, 60.8% and 48.4% of winter wheat–summer maize, respectively, but they showed a better feeding efficiency than the winter wheat–summer maize system. On the whole, spinach–spring maize may be a good option to prevent further decline in groundwater level and to ensure food security in a sustainable way.

The incorporation of lipid ingredients into food matrices presents a main drawback—their susceptibility to oxidation—which is associated with the loss of nutritional properties and the generation of undesirable flavors and odors. Oil-in-water emulsions are able to stabilize and protect lipid compounds from oxidation. Driven by consumers’ demand, the search for natural emulsifiers, such as proteins, is gaining much interest in food industries. This paper evaluates the in vitro emulsifying properties of protein hydrolysates from animal (whey protein concentrate) and vegetal origin (a soy protein isolate). By means of statistical modelling and bi-objective optimization, the experimental variables, namely, the protein source, enzyme (i.e., subtilisin, trypsin), degree of hydrolysis (2–14%) and emulsion pH (2–8), were optimized to obtain their maximal in vitro emulsifying properties. This procedure concluded that the emulsion prepared from the soy protein hydrolysate (degree of hydrolysis (DH) 6.5%, trypsin) at pH 8 presented an optimal combination of emulsifying properties (i.e., the emulsifying activity index and emulsifying stability index). For validation purposes, a fish oil-in-water emulsion was prepared under optimal conditions, evaluating its physical and oxidative stability for ten days of storage. This study confirmed that the use of soy protein hydrolysate as an emulsifier stabilized the droplet size distribution and retarded lipid oxidation within the storage period, compared to the use of a non-hydrolyzed soy protein isolate.

One of the key components essential to the productivity of small-scale farmers who secured farms through the land redistribution programme in South Africa is access to reliable sources of water for irrigation. In this study, we deployed a stakeholder-oriented qualitative research methodology to understand the extent to which land reform farming schemes in Bela-Bela and Greater Sekhukhune have been able to access water and use it to enhance their agricultural production. We were keen to identify and articulate the water-related challenges and missing ingredients for successful agricultural production on the new farming schemes. The study found that access to water for irrigated agriculture is not guaranteed for most of the emerging farmers and they do not have the finance needed to invest in sustainable water supply systems for irrigation. As a result, the majority of the farmers in our study sample have not been able to realize any meaningful agricultural production, with their farming schemes being either underutilized or not functioning at all. Other key challenges include lack of finance, high costs of electricity, and lack of farming knowledge among the emerging farmers. The paper concludes that there is need for key actors in the development sector to provide more substantive post-land transfer support and ensure better access to water for the emerging farmers. This will enhance the farmers' chances of realizing more meaningful agricultural production while improving their livelihoods.

Issues of water scarcity, food crisis, and ecological degradation pose great challenges to the sustainable development of Central Asia. In this study, a bi-level chance-constrained programming (BCCP) method is developed for planning water-food-ecology (WFE) nexus system of the Amu Darya River basin, where the efficiency of water-trading mechanism and the impact of uncertain water-availability are examined. This is the first attempt for planning WFE nexus system by incorporating chance-constrained programming (CCP) within a bi-level optimization framework. BCCP can reflect the risk of violating probabilistic constraint under uncertainty as well as balance the tradeoff between two-level decision makers in the WFE nexus system. Under trading scheme, multiple scenarios in association with different food demand, ecological-water requirement, and water availability are examined. Major findings are: (i) compared with that under non-trading, system benefits would increase [3.9, 20.4]% under trading scenarios, disclosing that water trading is an effective mechanism for the study basin; (ii) when food demand increases 10.5%, water allocated to ecological use would decrease [0.9, 2.7]% under all scenarios, revealing that agriculture can squeeze ecological water; (iii) both system benefit and water allocation would increase with p level, implying there is a tradeoff between system benefit and system-failure risk. These findings can gain insight into the interaction between two-level stakeholders and objectives as well as provide decision support for WFE nexus synergetic management.

Halogenated organic compounds are a particular group of contaminants consisting of a large number of substances, and of great concern due to their persistence in the environment, potential for bioaccumulation and toxicity. Some of these compounds have been classified as persistent organic pollutants (POPs) under The Stockholm Convention and many toxicity assessments have been conducted on them previously. In this work we provide an overview of enzymatic assays used in these studies to establish toxic effects and dose-response relationships. Studies in vivo and in vitro have been considered with a particular emphasis on the impact of halogenated compounds on the activity of relevant enzymes to the humans and the environment. Most information available in the literature focuses on chlorinated compounds, but brominated and fluorinated molecules are also the target of increasing numbers of studies. The enzymes identified can be classified as enzymes: i) the activities of which are affected by the presence of halogenated organic compounds, and ii) those involved in their metabolisation/detoxification resulting in increased activities. In both cases the halogen substituent seems to have an important role in the effects observed. Finally, the use of these enzymes in biosensing tools for monitoring of halogenated compounds is described.

Gathala et al., 'Enabling smallholder farmers to sustainably improve their food, energy and water nexus while achieving environmental and economic benefits', Renewable and Sustainable Energy Reviews 120, no. 109645 (2020): 16 p.