Forecasts on population growth and economic development indicate that there will be substantial increases in food demand for the forthcoming decades. We focus here on the water requirements of food production, on the issue of whether there would be enough water to produce sufficient food in the future, and we offer options to face this challenge based on recent trends observed in some agricultural systems. Given the competition for water faced by the agricultural sector, and the uncertainties associated with climate change, improving the efficiency of water use in both rain-fed and irrigated systems is the main avenue to face the challenge. In rain-fed agriculture, managing the risk associated with rainfall variability is a promising option to increase productivity. In irrigated systems, a case study on the improvements in water productivity in Andalusia, Spain, is used to illustrate some of the opportunities to make progress. Progress in reducing irrigation water use in recent decades has been substantial, but decreasing the consumptive use of crops is a much more difficult challenge. The need for more research and technology transfer on improving water-limited crop production is highlighted, and emphasis is placed on interdisciplinary approaches to gain the insight needed to achieve new breakthroughs that would help in tackling this complex problem.

Culture-independent techniques were used for the detection of pathogenic bacteria in drinking water at potentially critical control points along the production lines at a German dairy company and a Spanish dry cured ham company. Denaturing gradient gel electrophoresis (DGGE) was used to describe bacterial population shifts indicating biological instability in the drinking water samples. Autochthonous bacteria were identified by sequencing the excised DGGE DNA bands. More specifically, real-time PCR was applied to detect a number of pathogenic bacteria, i.e. Listeria monocytogenes, Mycobacterium avium subsp. paratuberculosis, Campylobacter jejuni, Enterococcus spp., Salmonella spp, Escherichia coli, and Pseudomonas aeruginosa. Due to the detection limits of the real-time PCR method, a specific protocol was established in order to meet the technical detection requirements and to avoid unwanted polymerase inhibitions. Autochthonous bacterial populations were found to be highly stable at most of the sampling points. Only one sampling point exhibited population shifts at the German dairy company. Enterococci and P. aeruginosa were detected in some water samples from these companies by molecular biology detection methods, but not by conventional culturing methods. Some opportunistic bacteria as Enterobacter sp., Acinetobacter, Sphingomonas sp. and non-pathogenic Bacillus, were also detected after DNA sequencing of DGGE bands.

The availability of freshwater is one of the biggest limitations and challenges of food production, as freshwater is an increasingly scarce and overexploited resource in many parts of the world. Therefore, the concept of water footprint (WF) has gained increasing interest, in the same way that the generation of food loss and waste (FLW) in food production and consumption has become a social and political concern. Along this line, the number of studies on the WF of the food production sector is currently increasing all over the world, analyzing water scarcity and water degradation as a single WF indicator or as a so-called WF profile. In Spain, there is no study assessing the influence of FLW generation along the whole food supply chain nor is there a study assessing the different FLW management options regarding the food supply chain’s WF. This study aimed to assess the spatially differentiated WF profile for 17 Spanish regions over time, analyzing the potential linkages of FLW management and water scarcity and water degradation. The assessment considered compliance and non-compliance with the Paris Agreement targets and was based on the life cycle assessment approach. Results are highlighted in a compliance framework; the scenarios found that anaerobic digestion and aerobic composting (to a lesser extent) had the lowest burdens, while scenarios with thermal treatment had the highest impact. Additionally, the regions in the north of Spain and the islands were less influenced by the type of FLW management and by compliance with the Paris Agreement targets. | This study has been conducted thanks to the financial support of the Project Ceres-Procom: Food production and consumption strategies for climate change mitigation (CTM2016-76176-C2-1-R) (AEI/FEDER, UE), financed by the Ministry of Economy and Competitiveness of the Government of Spain. Daniel Hoehn thanks the Ministry of Economy and Competitiveness of the Spanish Government for their financial support via the research fellowship BES-2017-080296. Thanks are also due to the FCT/MCTES for the contracts granted to Paula Quinteiro (CEECIND/00143/2017) and for the financial support to CESAM (UIDB/50017/2020+UIDP/50017/2020) by means of national funds.

A molecular epidemiology study of Salmonella serotype Enteritidis was carried out by ribotyping performed with a mixture of PstI and SphI (PS ribotyping), and randomly amplified polymorphic DNA (RAPD) typing conducted with the OPB17 primer. A series, including 38 food and 25 water strains, which were epidemiologically unrelated and collected in Spain over 1985-1996, was differentiated into 20 PS ribotypes [discrimination index (DI) = 0.67], RAPD types (DI = 0.28), and by combining both methods into 23 genomic groups (DI = 0.76). With ribotyping data from the strains tested in this and in a previous work, including clinical and reference strains, a similarity dendrogram was traced and the subsequent branches and groupings were correlated with RAPD types, phage types and sources of origin. At a similarity level of 55%, a major cluster (grouping five subclusters and three single branches) and two minor clusters were revealed. Results supported the fact that organisms representing, at least, 40 genomic groups are currently circulating in Spain, but that only the organisms of five groups predominate and these fall into a single subcluster or lineage. Organisms of these five groups could be considered endemic, associated with food-borne human infections and, for epidemiological purposes, can be differentiated by phage typing. The most frequent phage types can be subdivided into genomic groups. Organisms of the prevalent genomic groups and several less frequent ones were mainly associated with poultry transmission and gastroenteritis as the major clinical forms, while organisms of another two frequent, groups were mainly associated with extra-intestinal infections, and organisms of four infrequent groups were only collected from sewage or environmental waters.

The availability of freshwater is one of the biggest limitations and challenges of food production, as freshwater is an increasingly scarce and overexploited resource in many parts of the world. Therefore, the concept of water footprint (WF) has gained increasing interest, in the same way that the generation of food loss and waste (FLW) in food production and consumption has become a social and political concern. Along this line, the number of studies on the WF of the food production sector is currently increasing all over the world, analyzing water scarcity and water degradation as a single WF indicator or as a so-called WF profile. In Spain, there is no study assessing the influence of FLW generation along the whole food supply chain nor is there a study assessing the different FLW management options regarding the food supply chain’s WF. This study aimed to assess the spatially differentiated WF profile for 17 Spanish regions over time, analyzing the potential linkages of FLW management and water scarcity and water degradation. The assessment considered compliance and non-compliance with the Paris Agreement targets and was based on the life cycle assessment approach. Results are highlighted in a compliance framework: the scenarios found that anaerobic digestion and aerobic composting (to a lesser extent) had the lowest burdens, while scenarios with thermal treatment had the highest impact. Additionally, the regions in the north of Spain and the islands were less influenced by the type of FLW management and by compliance with the Paris Agreement targets.

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.

The study of the impact of economic activities on natural resources through global supply chains is increasingly demanded in the context of the growing globalization of economies and product fragmentation. Taking Spain as a case study and a sector with significant economic and environmental impacts, the agri-food industry, the objective of this work is two-fold. First, we estimate the associated water impact, both from the production and consumption perspectives, paying special attention to the water embodied in production exchanges among countries and sectors. To that aim, we use an environmentally-extended multiregional input-output model (MRIO). Second, we assess the main driving factors behind changes in direct and embodied water consumption between the years 1995 and 2009 by means of a structural decomposition analysis. The MRIO model provides a comprehensive estimate of the economic linkages among regions and economic sectors and, therefore, allows calculating the environmental impacts over international value chains. The results indicate that the food industry exerts large impacts on global water resources, particularly given the remarkable interactions with the domestic and foreign agricultural sectors, These growing linkages show how consumption patterns, and, therefore, lifestyles, involve large environmental impacts through the whole and global supply chains.

A nexus approach can support the transition to sustainability by addressing trade-offs and pursuing synergies to improve water, energy, and food security. In this paper, a participatory system dynamics model was developed to identify and assess the key interlinkages between water, food, and energy in Andalusia (Spain). A panel of relevant stakeholders contributed to all stages of the model’s development. Further, by calibrating the model to CAPRI-Water projections until 2050, the evolution of the system under a plausible climate scenario, as well as effects of water prices changes, was evaluated. The results revealed a close link between water cost, irrigation water use, energy consumption, and the economic development of agriculture in the region. Large variability was observed in the effects of water pricing policies across crops. This paper concludes that a participatory system dynamics model can help in understanding the nexus synergies and can support the design of more coherent sustainability strategies in the region.

This paper proposes a framework for the identification, assessment and analysis of the water–energy–food nexus at a basin scale. This methodology is applied to the Duero river basin in Spain to detect the most important conflicts derived from water, food and energy interdependencies. Some of the most important issues are the limitations posed by rising energy prices for irrigated agriculture due to modernization, limitations to water treatment, and the possible emergence of new water demands for energy by hydraulic fracturing for oil and gas and enhanced bioenergy.

The introduction of drug residues into the food chain and their presence in drinking water has been recently investigated. The aim of this work was to monitor the presence of 19 active drugs in water samples collected from milking parlors of dairy farms located in Galicia (northwest Spain), one of the main Spanish milking areas. Overall, 65% of the samples tested positive for at least one of the compounds analyzed. A total of 12 drugs were measured, with concentrations ranging between 17 and 3,941 ng/L. Considering that a mixture of compounds may contribute to the overall effect of each compound and might increase or reduce its toxicity, it should be noted that 29% of the samples tested contained more than one pharmaceutical. To date, the effects of the continuous consumption of these mixtures of drugs in water or milk are unknown; however, antimicrobials may affect the human gut microbiota or have toxic effects in sensitive individuals.