Water, energy, and food are lifelines for modern societies. The continuously rising world population, growing desires for higher living standards, and inextricable links among the three sectors make the water-energy-food (WEF) nexus a vibrant research pursuit. For the integrated delivery of WEF systems, quantifying WEF connections helps understand synergies and trade-offs across the water, energy, and food sectors, and thus is a critical initial step toward integrated WEF nexus modeling and management. However, current WEF interconnection quantifications encounter methodological hurdles. Also, existing calculation results are scattered across a wide collection of studies in multiple disciplines, which increases data collection and interpretation difficulties. To advance robust WEF nexus quantifications and further contribute to integrated WEF systems modeling and management, this study: (i) summarizes the estimate results to date on WEF interconnections: (ii) analyzes methodological and practical challenges associated with WEF interconnection calculations: and (iii) points out opportunities for enabling robust WEF nexus quantifications in the future.

Molecular Microbial Diagnostic Methods: Pathways to Implementation in the Food and Water Industries attempts to address the shortage of guidance on implementation of molecular-based methods for routine diagnostic laboratories. What industry and analysts can expect from routine use of these methods is discussed and outlined. The book uncovers industry needs for the use of molecular methods by providing a brief history of water and food analysis for the pathogens of concern. It also describes the potential impact of current and cutting-edge molecular methods. It discusses the advantages of the implementation of molecular methods, describes information on when and how to use specific methods, and presents why one should utilize them for pathogen detection in the routine laboratory. The reference material in the book is also pertinent for anyone carrying out microbiological analysis at the research level and covers a wide spectrum of classical and cutting-edge methods.

This paper is a perspective paper, which investigates whether the water footprint (WF) concept addresses the water–food–energy–ecosystem nexus. First, the nexus links between (1) the planetary boundary freshwater resources (green and blue water resources) and (2) food security, energy security, blue water supply security and water for environmental flows/water for other ecosystem services (ES) are analysed and graphically presented. Second, the WF concept is concisely discussed. Third, with respect to the nexus, global water resources (green and blue) availability and use are discussed and graphically presented with an indication of quantities obtained from the literature. It is shown which of these water uses are represented in WF accounting. This evaluation shows that general water management and WF studies only account for the water uses agriculture, industry and domestic water. Important water uses are however generally not identified as separate entities or even included, i.e. green and blue water resources for aquaculture, wild foods, biofuels, hydroelectric cooling, hydropower, recreation/tourism, forestry (for energy and other biomass uses) and navigation. Fourth, therefore a list of essential separate components to be included within WF accounting is presented. The latter would be more coherent with the water–food–energy–ecosystem nexus and provide valuable extra information and statistics.

Water, food and energy are at the core of human needs and there is a boundless complex cycle among these three basic human needs. Ecosystems are in the center of this nexus, since they contribute to the provision of each component, making it imperative to understand the role of ecosystems in securing food, water and energy for human well-being. In this study we aimed to map and assess water provisioning services and associated benefits to support the ecosystem–water–food–energy nexus by taking into account environmental flow requirements for riverine ecosystems using the hydrological model Soil and Water Assessment Tool (SWAT). We developed a framework that includes indicators of renewable water (capacity of ecosystem to provide water) and water use (service flow) and we applied it in the Danube river basin over the period 1995–2004. Water scarcity indicators were used to map the possible water scarcity in the subbasins, and analyze the spatial match of water availability and water use. The results show that modelling is instrumental to perform the integrated analysis of the ecosystem–water–food–energy nexus; and that spatial mapping is a powerful tool to display environmental availability of water provisioning and regulatory services delivered by ecosystems, and can support the nexus analysis.

We quantify the potential impacts of global food production on freshwater availability (water scarcity footprint; WSF) by applying the water unavailability factor (fwua) as a characterization factor and a global water resource model based on life cycle impact assessment (LCIA). Each water source, including rainfall, surface water, and groundwater, has a distinct fwua that is estimated based on the renewability rate of each geographical water cycle. The aggregated consumptive water use level for food production (water footprint inventory; WI) was found to be 4344 km3/year, and the calculated global total WSF was 18,031 km3 H<inf>2</inf>Oeq/year, when considering the difference in water sources. According to the fwua concept, which is based on the land area required to obtain a unit volume of water from each source, the calculated annual impact can also be represented as 98.5 × 106 km2. This value implies that current agricultural activities requires a land area that is over six times larger than global total cropland. We also present the net import of the WI and WSF, highlighting the importance of quantitative assessments for utilizing global water resources to achieve sustainable water use globally.

Materials, energy, and organisms from groundwater serve as resource subsidies to lotic systems. These subsidies influence food production and post-emergent fish growth and condition through nutrient inputs and water temperature changes. To test whether post-emergent fish grew faster in gaining sites, we grew hatchery post-emergent salmon in enclosures, sampled periphyton, benthic invertebrates and wild salmon, and modeled fish growth across a gradient of groundwater-surface water exchange. Fish grew almost twice as fast in gaining (2.7 % g d | The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author.

Materials, energy, and organisms from groundwater serve as resource subsidies to lotic systems. These subsidies influence food production and post-emergent fish growth and condition through nutrient inputs and water temperature changes. To test whether post-emergent fish grew faster in gaining sites, we grew hatchery post-emergent salmon in enclosures, sampled periphyton, benthic invertebrates, and wild salmon, and modeled fish growth across a gradient of groundwater – surface water exchange. Fish grew almost twice as fast in gaining (2.7%·day⁻¹) than in losing (1.5%·day⁻¹) sites. Fish from transient sites grew as much as gaining sites, but their condition was significantly lower (18.3% vs. 20.7%). Results suggest that groundwater – surface water exchange affects fish growth and energetic condition through direct and indirect pathways. Elevated nitrogen concentrations and consistently warmer water temperature in gaining sites have a strong effect on basal production with subsequent effects on invertebrate biomass, fish growth, and condition. Findings highlight the importance of groundwater – surface water exchange as a subsidy to rearing salmon and may inform strategies for restoring fish rearing habitat.