"Water, energy and food are key resources to sustain life, and are fundamental to national, regional, and global economies. These three resources are interlinked in multiple ways, and the term 'nexus' captures the interconnections. The nexus has been discussed, debated, researched, and advocated widely but the focus is often on the pairings of 'water-energy' or 'water-food' or 'energy-food'. To really benefit from the nexus approach in terms of resource use efficiency, it is essential to understand, operationalize, and practice the nexus of all three resources. As demand for these resources increases worldwide, using them sustainably is a critical concern for scientists, citizens, governments, and policymakers. Water-Energy-Food Nexus: Principles and Practices is a valuable resource for students, research scholars, and professionals in academic institutions with strong interests in interdisciplinary research involving geography, earth science, environmental science, environmental management, sustainability science, international development, and ecological economics. The volume will also be useful for professionals, practitioners and consultants in NGOs, government, and international agencies"--Back cover.

Global challenges have exacerbated a search for solutions to poverty and environmental degradation. Integration it was argued would help address the twin challenge. Integrated Water Resources Management (IWRM) was supposed to be that magic bullet and was embraced by scientists because of the clinical efficiency with which it argued for integrated analysis of sectors and resources and of systems and scale conditions. This paper argues that effective implementation of the Water-Energy-Food (WEF) Nexus can be supported by robust science. The corollary that robust science automatically leads to effective implementation is not always known to be true. The nexus approach sheds light on the challenges of implementation by introducing concepts of trade-offs and thresholds and consequently emphasizes the importance of transdisciplinary approaches to sustainable development. This paper reviews the results of recent research to offer tentative answers to the following questions: (a) Why is the governance dimension important to undertake an integrated analysis of water-energy-food challenges? (b) What does the nexus approach connote in normative and institutional terms? (c) What does implementation mean in nexus terms? (d) How can we establish if the nexus approach is an improvement over business as usual? and (e) What tools are available that would enable translation of results of scientific research to create an evidence base that would enable decision makers to act in support of sustainable development?

The review papers presented in this special issue all derive from an NSF sponsored workshop held in January 2017, in College Station, Texas: FEW Nexus Workshop on Integrated Science, Engineering, and Policy: a Multi Stakeholder Dialogue Symposium. The workshop was organized by the Texas AM WEF Nexus Initiative, and their scientific committee partners: Prairie View AM and Texas AM-San Antonio, Purdue University, Ohio State University, National Council for Science and Environment (NCSE), Columbia University, World Wildlife Federation, University of Texas, Rice University, Los Alamos National Lab, Future Earth, Texas Christian University, Circle of Blue, University of California-Riverside, International Food Policy Research Institute, National Renewable Energy Laboratory, University of New Mexico, Pennsylvania State University, University of Minnesota, and Water Future. The papers represent the work of the scientists and professionals hailing from the private and industrial sectors, government agencies, and research and educational institutions.

El presente trabajo es un resumen en que el agua, está presente en todo alimento, ya sea fruta, pescado, carnes rojas, verduras, hortalizas, alimentos líquidos y otros, así mismo este componente que está en porcentaje mayoritario, es la que reacciona con las grasas, carbohidratos, proteínas, minerales y vitaminas, las cuales tienen funciones específicas en el cuerpo humano. Todo alimento tiene un porcentaje determinado como su actividad de agua, así el agua tiene dos tipos de agua siendo agua ligada y agua libre, siendo este último el que mayor cantidad o porcentaje, está presente en cada alimento. Cada alimento tiene una actividad de agua, siendo tres tipos: Tipo 1, Tipo 2 y Tipo 3, el cual tiene determinados valores: 1.00 – 0.80, 0.25 – 0.80 7 menor de 0.25, cada alimento tiene un determinado tiempo de vida útil, que está relacionado por el contenido de su actividad y porcentaje de agua libre, el cual esta registrada en sus gráficas correspondiente, porque cada alimento tiene un comportamiento diferente uno de otro (frutas, carnes, hortalizas, etc.). Así mismo dentro de la distribución del agua en los alimentos hay alimentos con alto contenido de agua (alimentos frescos como frutas, hortalizas, verduras, alimentos líquidos), alimentos con humedad intermedia (cereales, derivados de estos, derivados de carnes, derivados de leche, soya, bebidas, leguminosas, oleaginosas) y por último alimentos altamente secos (alimentos secos como: leche en polvo, café instantáneo, aceites vegetales, productos con humedad menor de 5% de agua libre). Un alimento bien procesado según el tipo de tecnología usada, tiene un largo tiempo de vida útil, porque para esto se realiza, estudios de prolongación de vida en anaquel, estas pruebas se realizan usando temperaturas altas forzando al alimento a condiciones extremas, de temperaturas, presión y tiempo. Así mismo en cada actividad de agua, existe un determinado microorganismo que se desarrolla, y altera la calidad del producto o alimento. | Trabajo academico

Population growth, increasing demands for food, ever-growing competition for water, reduced supply reliability, climate change and climate uncertainty and droughts, decline in critical ecosystems services, competition for land use, changing regulatory environments, and less participatory water resources governance are contributing to increasing difficulties and challenges in water resource management for agriculture and food. The need for sustainable food security for our global population and the need for preserving the environment, namely natural and man-made ecosystems and landscapes, have created an increased need for integrated, participative and scalable solutions focusing the various levels of irrigation and nature water management, from the field crop to the catchment and basin scales. Meanwhile, challenges and issues relative to water management for agriculture and food have evolved enormously in the last 30 years and the role of active management of the components of the water cycle is assuming an increased importance since their dynamics are key to assure water use sustainability, mainly agriculture and natural ecosystems sustainability. However, different regions face context-specific challenges associated with water scarcity, climate, governance, and population requirements. The main and first challenge is producing enough food for a growing population, which is intimately related with challenges placed to agricultural water management, mainly irrigation management. This paper revises challenges and progress achieved in the last 30 years focusing on irrigated agriculture, mainly water management, and its contribution to food security and the welfare of rural communities.

Water, food and energy are strongly interconnected. In this study we address this issue taking the lens of financial concerns to investigate the WFE relationship. Specifically, the aim of our paper is to analyze the volatility spillovres between indexes representing the financial component of WFE nexus. We use a multivariate GARCH model with daily data from November 2001 to May 2013. Water is proxy by equity index that represents the performance of the industry involved in water business both at global and local level. For the food and energy sectors we use two sub-indexes of S&P GF-Commodity Index. Our results highlight the existences of a financial nexus between WFE that is particular exacerbated during 2008 crisis. Evidence therefore suggests the need to better investigate the policy options that can be used to reduce price volatility in a framework of a rising relevance of water issues within the nexus.