Water use and agricultural practices in the Mediterranean area are unsustainable. The situation is worsened by the increased frequency of droughts and floods, as well as desertification and soil depletion, associated with climate change. The aim of Partnership for Research and Innovation in the Mediterranean Area (PRIMA) is to foster an integrated programme of sustainable food production and water provision in the framework of the water-energy-food nexus. A monitoring tool developed under PRIMA is based on the Sustainable Development Goals, two of which are specifically dedicated to food security (SDG 2) and sustainable management of water (SDG 6).The 12 indicators that have been chosen to be monitored in the Mediterranean area are: Multidimensional Poverty Index (MPI); population overweight (%); land use (%); GHG emissions (total and AFOLU)(tCO₂ₑ); cereal yield (kg/ha); agriculture value added (US$/worker); fertilizer consumption (kg/haₐᵣₐbₗₑ ₗₐₙd); crop water productivity (kg/m³); annual freshwater withdrawal for agriculture (%); population served using with safely managed water service (rural, %); population served using with safely managed sanitation (rural, %); amount of agricultural residues used for energy purposes (t). Datasets for these indicators are collected by international bodies such as the World Bank, WHO, FAO and UNFCCC; recent series are available for almost all Mediterranean countries and are constantly updated. The aim of the proposed monitoring tool is to keep track of the impact generated in by PRIMA research and innovation projects Mediterranean countries.

The efficient provision of food, energy, and water (FEW) resources to cities is challenging around the world. Because of the complex interdependence of urban FEW systems, changing components of one system may lead to ripple effects on other systems. However, the inputs, intersectoral flows, stocks, and outputs of these FEW resources from the perspective of an integrated urban FEW system have not been synthetically characterized. Therefore, a standardized and specific accounting method to describe this system is needed to sustainably manage these FEW resources. Using the Detroit Metropolitan Area (DMA) as a case, this study developed such an accounting method by using material and energy flow analysis to quantify this urban FEW nexus. Our results help identify key processes for improving FEW resource efficiencies of the DMA. These include (1) optimizing the dietary habits of households to improve phosphorus use efficiency, (2) improving effluent-disposal standards for nitrogen removal to reduce nitrogen emission levels, (3) promoting adequate fertilization, and (4) enhancing the maintenance of wastewater collection pipelines. With respect to water use, better efficiency of thermoelectric power plants can help reduce water withdrawals. The method used in this study lays the ground for future urban FEW analyses and modeling.

Thesis (PhD)--University of Pretoria, 2018. | Diarrheagenic Escherichia coli (DEC) has been implicated in foodborne outbreaks worldwide and additionally associated with childhood stunting in the absence of diarrhoea. DEC are pathogenic E. coli that cause human gut gastrointestinal infections. They are categorized based on how they elicit disease into groups called pathotypes. Infection is extraordinarily common, but the routes of transmission have not been determined. This work categorized into three phases 1, 2 and 3 aimed at characterizing pathogenic E. coli previously isolated from food sources and irrigation water in South Africa. In phase 1, the study characterized 205 E. coli strains previously isolated from producer distributor bulk milk (PDBM)(n=118), irrigation water (n=48), irrigated lettuce (n=29) and street vendor coleslaw (n=10) in South Africa. Enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), enteroaggregative E. coli (EAEC) and diffusely adherent E. coli (DAEC) were sought. The study used PCR and partial gene sequencing for all 205 strains while 46 out of 205 that showed poor resolution were subsequently characterized using cell adherence (HeLa cells). PCR and partial gene sequencing of aatA and/or aaiC genes confirmed EAEC (2%, 5 out of 205) as the only pathotype. Strains from Genbank showing ?80% nucleotide sequence similarity with those used in this study based on possession of the aaiC gene included 10 clinical and 5 food strains. On the other hand, all strains from GenBank (n=22) showing high nucleotide sequence similarity (?80%) to those from this study based on possession of the aatA gene were clinical. Cluster analysis of sequenced EAEC strains with E. coli strains in GenBank showing ?80% nucleotide sequence similarity based on possession of aaiC and aatA generated distinct clusters of strains separated predominantly based on their source of isolation (food source or human stool). This suggested a potential role of virulence genes in source tracking. EAEC 24%, 11 out of 46 strains (PDBM=15%, irrigation water=7%, irrigated lettuce=2%) was similarly the predominant pathotype followed by strains showing invasiveness to HeLa cells, 4%, 2 out of 46 (PDBM=2%, irrigated lettuce=2%), using cell adherence. All strains that were not characterized based on possession of virulence genes and cell adherence assays were designated as non-DEC. These non-DEC strains were subsequently used as the basis for characterization in phase 2. In phase 2, the study assayed non-DEC strains from environmental sources in South Africa for phenotypes that may be associated with intestinal dysfunction (ID). DEC strains were also used. The strains had previously been isolated from PDBM, irrigated lettuce, street vendor coleslaw and irrigation water. In-vitro assays included; biofilm formation (n=38), extracellular polymeric substance (EPS) formation (n=38), cytotoxic activity (n=10), disruption of tight junctions and induction of Interleukin 8 (IL-8) on polarized T-84 cells (n=20). The number of strains tested for each assay differed, depending on prior molecular and phenotypic characterization that signalled potential pathogenicity. Subsequently, all strains having data points for all analyses were used to compute Principal Component Analysis (PCA) plot curves to infer associations amongst test strains. Biofilm formation varied based on pathotype (DEC and non-DEC) and source of isolation suggesting these two factors influence persistence within a defined environmental niche. Additionally, DEC isolated from irrigated lettuce had significantly higher (p?0.05) biofilm formation in both media compared to all strains including DEC standard controls suggesting irrigated lettuce as a potential source of persistent pathogenic strains. All strains were able to form EPS suggesting ability to form mature biofilms. Of the (60%, 6 out of 10) strains showing cytotoxic activity, most (83%, 5 out of 6 strains) were non-DEC isolated from food sources. Mean percentage reduction in initial TER (a measure of intestinal disruption) in all test strains, was comparable (53.5 to 73.8%) to that observed in the standard DEC. Additionally, IL-8 induction from strains isolated from PDBM (139pg/mL), irrigation water (231.93pg/mL) and irrigated lettuce (152.98pg/mL) was significantly higher (p?0.05) than in the commensal strain aafa. PCA categorized strains based on sources of isolation and showed potential for use in source tracking. This study shows that non-DEC strains along the food chain possess characteristics that may lead to ID. However further investigations with a larger collection of strains may provide a clearer link to these observations. | Food Science | PhD

With the notion of the Water-Energy-Food Nexus long neglected interlinkages between water, energy, and food are becoming visible. Yet, the diversity in understandings of the Nexus (as an analytical tool and political agenda) is the starting point for our research interest, stemming as it does from a governance perspective. The contributions of this special issue highlight different facets of governance around the Nexus. While some papers attempt to conceptualize the Nexus-Governance further, others clearly have an empirical focus. Thereby this special issue provides a rich body of work for further WEF-Nexus studies and integrative policies, such as the SDGs.

Negative emission technologies such as bioenergy with carbon capture and storage (BECCS) are regarded as an option to achieve the climatic target of the Paris Agreement. However, our understanding of the realistic sustainable feasibility of the global lands for BECCS remains uncertain. In this study, we assess the impact of BECCS deployment scenarios on the land systems including land use, water resources, and ecosystem services. Specifically, we assess three land-use scenarios to achieve the total amount of 3.3 GtC year⁻¹ (annual negative emission level required for IPCC-RCP 2.6) emission reduction by growing bioenergy crops which requires huge use of global agricultural and forest lands and water. Our study shows that (1) vast conversion of food cropland into rainfed bio-crop cultivation yields a considerable loss of food production that may not be tolerable considering the population increase in the future. (2) When irrigation is applied to bio-crop production, the bioenergy crop productivity is enhanced. This suppresses the necessary area for bio-crop production to half, and saves the land for agricultural productions. However, water consumption is doubled and this may exacerbate global water stress. (3) If conversion of forest land for bioenergy crop cultivation is allowed without protecting the natural forests, large areas of tropical forest could be used for bioenergy crop production. Forest biomass and soil carbon stocks are reduced, implying degradation of the climate regulation and other ecosystem services. These results suggest that without a careful consideration of the land use for bioenergy crop production, a large-scale implementation of BECCS could negatively impact food, water and ecosystem services that are supporting fundamental human sustainability.

This study proposed a holistic three-fold scheme that synergistically optimizes the benefits of the Water-Food-Energy (WFE) Nexus by integrating the short/long-term joint operation of a multi-objective reservoir with irrigation ponds in response to urbanization. The three-fold scheme was implemented step by step: (1) optimizing short-term (daily scale) reservoir operation for maximizing hydropower output and final reservoir storage during typhoon seasons; (2) simulating long-term (ten-day scale) water shortage rates in consideration of the availability of irrigation ponds for both agricultural and public sectors during non-typhoon seasons; and (3) promoting the synergistic benefits of the WFE Nexus in a year-round perspective by integrating the short-term optimization and long-term simulation of reservoir operations. The pivotal Shihmen Reservoir and 745 irrigation ponds located in Taoyuan City of Taiwan together with the surrounding urban areas formed the study case. The results indicated that the optimal short-term reservoir operation obtained from the non-dominated sorting genetic algorithm II (NSGA-II) could largely increase hydropower output but just slightly affected water supply. The simulation results of the reservoir coupled with irrigation ponds indicated that such joint operation could significantly reduce agricultural and public water shortage rates by 22.2% and 23.7% in average, respectively, as compared to those of reservoir operation excluding irrigation ponds. The results of year-round short/long-term joint operation showed that water shortage rates could be reduced by 10% at most, the food production rate could be increased by up to 47%, and the hydropower benefit could increase up to 9.33 million USD per year, respectively, in a wet year. Consequently, the proposed methodology could be a viable approach to promoting the synergistic benefits of the WFE Nexus, and the results provided unique insights for stakeholders and policymakers to pursue sustainable urban development plans.

This paper assesses the sustainability of bioenergy production under a nexus perspective through a new efficiency type index. The index describes 1st generation biofuel production under the perspective of the implied consumption of natural resources. We consider the sustainability of energy production as a sequence of steps, each characterised by its efficiency, and propose an index which returns an overall efficiency value describing the adequacy or inadequacy of the considered processes under a nexus perspective. The direct application of the nexus index entails an indication of the possible improvements needed to move production towards most sustainable processes or places. Moreover, it allows evaluating the efficiency of the main crops currently used in biofuel production with respect to the water–food–energy nexus. The results depict countries presently capable of performing sustainable production of 1st generation biofuel from particular crops. Furthermore, the analysis of the single components of the nexus index allows understanding the effects of possible improvements (e.g. soil and water management, new generation biofuels) on the overall production efficiency under a nexus perspective.

The improvement of the sustainability of global food systems is a top priority. Many efforts have targeted the production side, yet managing food consumption demand, i.e., people’s eating habits, might deliver important co-benefits from a land, water, and energy perspective. This paper focuses on assessing the water-related implications of food consumption and waste among Spanish consumers to discern possible policy recommendations. Specifically, we estimated the water footprint (WF) of the diet and associated food waste of Spanish households from October 2014 to September 2015, broken down by WF component (green, blue and grey) and its geographical origin. Our results showed that, for the analyzed period, the WF of food consumption in Spain is 52,933 hm3, equivalent to 3302 liters per person and day. The consumptive fraction (green + blue water) of this diet-related WF accounts for 89%, while the remaining 11% (127 m3 per person/year) is attributed to water quality impacts (grey water). The products that account for the largest share in the total WF are meat, fish and animal fats (26%) and dairy products (21%). Likewise, roughly 41% of the total WF linked to household diets is foreign, i.e., imported virtual water, and the main countries of origin are Tunisia, Portugal, and France. The WF of food waste accounts for 2095 hm3, equivalent to 131 liters per person and day. From a policy perspective, several studies have highlighted that high water savings can be achieved by reducing food waste; in Spain, however, eliminating food waste at household level would reduce the Spanish food-related WF by only 4% (292 hm3 of blue water and 1555 hm3 of green water). In the light of these results, a shift back to a Mediterranean diet, in which fruits and vegetables account for a larger share of the food intake, would deliver greater water savings.

Global food trade entails virtual flows of agricultural resources and pollution across countries. Here we performed a global-scale assessment of impacts of international food trade on blue water use, total water use, and nitrogen (N) inputs and on N losses in maize, rice, and wheat production. We simulated baseline conditions for the year 2000 and explored the impacts of an agricultural intensification scenario, in which low-input countries increase N and irrigation inputs to a greater extent than high-input countries. We combined a crop model with the Global Trade Analysis Project model. Results show that food exports generally occurred from regions with lower water and N use intensities, defined here as water and N uses in relation to crop yields, to regions with higher resources use intensities. Globally, food trade thus conserved a large amount of water resources and N applications, and also substantially reduced N losses. The trade-related conservation in blue water use reached 85km³y⁻¹, accounting for more than half of total blue water use for producing the three crops. Food exported from the USA contributed the largest proportion of global water and N conservation as well as N loss reduction, but also led to substantial export-associated N losses in the country itself. Under the intensification scenario, the converging water and N use intensities across countries result in a more balanced world; crop trade will generally decrease, and global water resources conservation and N pollution reduction associated with the trade will reduce accordingly. The study provides useful information to understand the implications of agricultural intensification for international crop trade, crop water use and N pollution patterns in the world.

Twenty-four adult Beagles were utilised to evaluate the partial replacement of wheat bran with corn gluten feed without steep water on digestibility and characteristics of faeces. The treatments were 0 (no substitution), 30, 60 or 90 g/kg of corn gluten without steep water. There was no effect (p > .05) on the digestibility coefficients (g/kg) of dry matter (0.771), organic matter (0.806), crude protein (0.813), ether extract (0.798), crude fibre (0.393), neutral detergent fibre (0.425), acid detergent fibre (0.286) and crude energy (0.812), whilst there was effect (p < .05) on the digestible and metabolisable energy. There were effects (p < .05) for dry matter and pH of faeces but no effect (p > .05) was found on the remaining faecal characteristics: excretion for 100 g of food (56.77 g), excretion (129.6 g/day and 49.0 g dry matter/day), score (3.90), dry matter excretion for 100 g of food (22.86 g), buffering capacity (BC) at pH 5 (57.81), ammonia nitrogen (1.46 g/kg of faecal dry matter) and water balance (333.25 mL/day), in vivo and in situ gas production (p > .05). Corn gluten feed without steep water can be utilised to replace up to 90 g/kg of wheat bran without causing negative effect on the digestibility and characteristics of faeces.