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Managing water for food and agricultural transformation in Africa: key issues and priorities النص الكامل
2019
Williams, Timothy O.
This chapter examines the links between water, food and society in Africa. Agricultural transformation to promote growth, eliminate poverty and hunger and sustain ecosystems is one of the central pillars of current development agenda in Africa. Achievement of this agenda will crucially depend on sustainable water management. However, agri-food systems and water resources are under greater pressure than ever before due to demographic, economic and climatic changes. The nature and scale of these changes suggest that only a holistic and integrated management of all shades of water resources, green, blue and grey, will allow Africa to eliminate hunger and poverty. Research-based technical solutions as well as institutional and policy measures are proposed that would allow available water resources to be sustainably used to promote climate-resilient farming systems, improve agricultural productivity and food security and spur the development of viable food value chains needed for agricultural and rural transformation.
اظهر المزيد [+] اقل [-]Governance of the water-energy-food security nexus: A multi-level coordination challenge النص الكامل
2019
Pahl-Wostl, Claudia
The Water-Energy-Food (WEF) nexus is increasingly perceived as promising approach to overcome governance failures in dealing with complex and interconnected resource management challenges. Are such expectations warranted and what is required to mobilize the transformative potential inherent in this approach? The paper addresses these questions and argues in favour of developing a nexus paradigm which guides processes of purposeful design and of self-organization of nexus governance systems. Such a paradigm could be anchored in addressing water, energy and food security from a nexus perspective if such a security concept is appropriately defined and operationalized. To develop the argument, governance challenges arising from the different logics of the concepts of water, energy and food security are addressed with a definition for WEF security from a nexus perspective. An analytical framework using a network and ecosystem services perspective is introduced. The power of the approach introduced is illustrated for a typical case to identify coordination failures and persistent sustainability problems but as well leverage points for transformative change. The paper concludes by elaborating on the transformative potential of the SDGs and on the role of a WEF nexus approach in realizing such a potential.
اظهر المزيد [+] اقل [-]A Systems Approach To Assess Trade Dependencies in U.S. Food–Energy–Water Nexus النص الكامل
2019
Vora, Nemi | Fath, Brian D. | Khanna, Vikas
We present a network model of the United States (U.S.) interstate food transfers to analyze the trade dependency with respect to participating regions and embodied irrigation impacts from a food–energy–water (FEW) nexus perspective. To this end, we utilize systems analysis methods including the pointwise mutual information (PMI) measure to provide an indication of interdependencies by estimating probability of trade between states. PMI compares observed trade with a benchmark of what is statistically expected given the structure and flow in the network. This helps assess whether dependencies arising from empirically observed trade occur due to chance or preferential attachment. The implications of PMI values are demonstrated by using Texas as an example, the largest importer in the U.S. grain transfer network. We find that strong dependencies exist not only just with states (Kansas, Oklahoma, Nebraska) providing high volume of transfer to Texas but also with states that have comparatively lower trade (New Mexico). This is due to New Mexico’s reliance on Texas as an important revenue source compared to its other connections. For Texas, import interdependencies arise from geographical proximity to trade. As these states primarily rely on the commonly shared High Plains aquifer for irrigation, overreliance poses a risk for water shortage for food supply in Texas. PMI values also indicate the capacity to trade more (the states are less reliant on each other than expected), and therefore provide an indication of where the trade could be shifted to avoid groundwater scarcity. However, some of the identified states rely on GHG emission intensive fossil fuels such as diesel and gasoline for irrigation, highlighting a potential tradeoff between crop water footprint and switching to lower emissions pumping fuels.
اظهر المزيد [+] اقل [-]The Groundwater‒Energy‒Food Nexus in Iran’s Agricultural Sector: Implications for Water Security النص الكامل
2019
Mirzaei, Atena | Saghafian, Bahram | Mirchi, Ali | Madani, Kaveh
This paper presents the first groundwater‒energy‒food (GEF) nexus study of Iran’s agronomic crops based on national and provincial datasets and firsthand estimates of agricultural groundwater withdrawal. We use agronomic crop production, water withdrawal, and energy consumption data to estimate groundwater withdrawal from electric-powered irrigation wells and examine agronomic productivity in Iran’s 31 provinces through the lens of GEF nexus. The ex-post GEF analysis sheds light on some of the root causes of the nation’s worsening water shortage problems. Access to highly subsidized water (surface water and groundwater) and energy has been the backbone of agricultural expansion policies in Iran, supporting employment in agrarian communities. Consequently, water use for agronomic crop production has greatly overshot the renewable water supply capacity of the country, making water bankruptcy a serious national security threat. Significant groundwater table decline across the country and increasing energy consumption underscore dysfunctional feedback relations between agricultural water and energy price and groundwater withdrawal in an inefficient agronomic sector. Thus, it is essential to implement holistic policy reforms aimed at reducing agricultural water consumption to alleviate the looming water bankruptcy threats, which can lead to the loss of numerous agricultural jobs in the years to come.
اظهر المزيد [+] اقل [-]Microcystin-RR: Occurrence, content in water and food and toxicological studies. A review النص الكامل
2019
Díez-Quijada, Leticia | Puerto, María | Gutiérrez-Praena, Daniel | Llana-Ruiz-Cabello, María | Jos, Angeles | Cameán, Ana M.
Microcystins (MCs) are hepatotoxins, produced by various species of cyanobacteria, whose occurrence is increasing worldwide owing to climate change and anthropogenic activities. More than 100 variants have been reported, and among them MC-LR is the most extensively studied, but there are other MC congeners that deserve to be investigated. The need for data to characterize the toxicological profile of MC variants other than MC-LR has been identified in order to improve risk assessment in humans and wildlife. Accordingly, the aim of this study was to evaluate the information available in the scientific literature dealing with MC-RR, as this congener is the second most common cyanotoxin in the environment. The review focuses on aspects such as occurrence in water and food, and toxicity studies both in vitro and in vivo. It reveals that, although MC-RR is a real hazard with a high exposure potential in some countries, little is known yet about its specific toxicological properties that differ from those of MC-LR, and important aspects such as genotoxicity and chronic effects have not yet been sufficiently addressed.
اظهر المزيد [+] اقل [-]Pinch Methods for Efficient Use of Water in Food Industry: A Survey Review النص الكامل
2019
Nemati-Amirkolaii, Keivan | Paris-Saclay Food and Bioproduct Engineering (SayFood) ; AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | ANR-17-CE10-0015,MINIMEAU,Minimisation des consommations d'eau dans les agro-industries par le développement d'une approche intégrée associant Empreinte Eau et Pinch massique(2017)
International audience | The implementation of sustainable water management practices, through the recycling and reuse of water, is essential in terms of minimizing production costs and the environmental impact of the food industry. This problem goes beyond the classical audit and housekeeping practices through developing a systemic water-using reduction strategy. The implementation of such an approach needs R&D development, especially for the food industry, where there is a lack of knowledge on: (a) process integration and (b) data on the pollutant indicators or (c) volumes of water used and discharged at specific steps of the food processing line. Since energy pinch analysis emerged, different variations of pinch methods have been developed. As a variation of pinch, Water pinch analysis is a global and systematic approach to minimize water consumption and discharges, especially for the most energy-intensive and water-consuming factories. Based on the nature of the food industry, the real systems are complex, multi-source multi-contaminant systems, the problem should be well formulated, including mathematical constraints (inequalities thresholds). Current work has reviewed comprehensive literature about different variations of pinch analysis. In continue, water pinch method deeply discussed and some relevant data concerning the water using process and pollutant indicators have been reviewed with emphasis on the food industry sector.
اظهر المزيد [+] اقل [-]Coupling and Coordination Degrees of the Core Water–Energy–Food Nexus in China النص الكامل
2019
Shasha Xu | Weijun He | Juqin Shen | Dagmawi Mulugeta Degefu | Liang Yuan | Yang Kong
Achieving sustainable development in the water&ndash:energy&ndash:food (WEF) nexus is gaining global attention. The coupling and coordination degrees are a way to measure sustainable development levels of a complex system. This study assessed the coupling and coordination degrees of the core WEF nexus and identified key factors that affect sustainable development. First, an index system for assessing coupling and coordination degrees of the core WEF nexus was built. Second, the development levels of three subsystems as well as the coupling and coordination degrees of the core WEF nexus in China were calculated. The results showed that from 2007 to 2016, the mean value of the coupling degree was 0.746 (range (0.01, 1)), which was a high level. This proved that the three resources were interdependent. Hence, it was necessary to study their relationship. However, the mean value of the coordination degree was 0.395 (range (0, 1)), which was a low level. This showed that the coordination development of the core WEF nexus in China was low. It is necessary to take some measures to improve the situation. According to the key factors that affect the development levels of water, energy, and food subsystems, the authors put forward some suggestions to improve the coordination development of the WEF system in China.
اظهر المزيد [+] اقل [-]Managing water for food and agricultural transformation in Africa: key issues and priorities النص الكامل
2019
Williams, Timothy O.
Food Safety on the Farm: Good Agricultural Practices and Good Handling Practices – Water النص الكامل
2019
Jaysankar De | Christopher R Pabst | Jessica Lepper | Renee M. Goodrich Schneider | Keith R. Schneider
Good agricultural practices (GAPs) and good handling practices (GHPs) encompass the general procedures growers, packers, and processors of fresh fruits and vegetables should follow to ensure the safety of their product. GAPs usually address preharvest practices (i.e., in the field), while GHPs cover postharvest practices, including packing and shipping. This 7-page fact sheet covers GAPs and GHPs relating to water use. This major revision is a part of the Food Safety on the Farm series and was written by Jaysankar De, Christopher R. Pabst, Jessica Lepper, Renée Goodrich-Schneider, and Keith R. Schneider and published by the UF/IFAS Food Science and Human Nutrition Department. http://edis.ifas.ufl.edu/fs136
اظهر المزيد [+] اقل [-]A Study on the Sustainable Development of Water, Energy, and Food in China النص الكامل
2019
Lei Jin | Yuanhua Chang | Xianwei Ju | Fei Xu
It is of great significance to deal with the relationship between external factors and the water-energy-food internal system for China&rsquo:s sustainable development. This paper takes China as the research object, uses the system dynamics method to construct a model for China&rsquo:s water-energy-food system, and introduces the &ldquo:two-child&rdquo: policy and trade friction as the scenario parameters for simulation. The main results of scenario simulation can be summarized as the following three points. In terms of water, the trade friction will hinder China&rsquo:s industrial water consumption into a low-consumption stage. In terms of energy, both the trade friction and the &ldquo:two-child&rdquo: policy, will not change the increasing trend of energy demand. In terms of food, if there is strong response to the &ldquo:two-child&rdquo: policy, there will be insufficient food inventory under the current capacity and import ratio. In short, this paper takes the sustainable development of water-energy-food as a starting point and puts forward policy suggestions on the comprehensive formulation of policies.
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