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Managing water and agroecosystems for food security
2013
Boelee, Eline
Managing water and agroecosystems for food security Texte intégral
2013
Boelee, Eline
Punjab’s Water Woes and India’s Food Security Texte intégral
2015
Khush, Gurdev S.
Ground water tables in Punjab are declining at alarming rates in most districts of Punjab. One of the major causes of declining water tables is the increased cropping intensity. Whereas cropping intensity in Punjab was only 120% until about 50 years ago, it is now 190%. With one crop per year, a balance was maintained between water extraction and aquifer recharge. With two crops per year, this balance has been altered. Homogenization of crops in the state has also exacerbated the problem. Even more serious threat to nation’s agriculture is climate change. Himalayan glaciers, which are water towers for our rivers, are retreating. This will reduce the water flow in our rivers. While the climate-change impact on our water availability is several years away, we must address immediate problem of declining water tables in the state. Suggested interventions include crop diversification, precision agriculture, including water saving technologies, and developing crop varieties with improved water-use efficiency.
Afficher plus [+] Moins [-]A metropolitan scale water management analysis of the food-energy-water nexus Texte intégral
2020
Guan, Xin | Mascaro, Giuseppe | Sampson, David | Maciejewski, Ross
Quantifying the interactions of the food-energy-water (FEW) nexus is crucial to support new policies for the conjunctive management of the three resources. Currently, our understanding of FEW systems in metropolitan regions is limited. Here, we quantify and model FEW interactions in the metropolitan area of Phoenix, Arizona, using the Water Evaluation and Planning (WEAP) platform. In this region, the FEW nexus has changed over the last thirty years due to a dramatic population growth and a sharp decline of cultivated land. We first thoroughly test the ability of WEAP to simulate water allocation to the municipal, agricultural, industrial, power plant, and Indian sectors against historical (1985–2009) data. We then apply WEAP under possible future (2010–2069) scenarios of water and energy demand and supply, as well as food production. We find that, if the current decreasing trend of agricultural water demand continues in the future, groundwater use will diminish by ~23% and this would likely result in aquifer safe-yield and reduce the energy demand for water. If agricultural activities decrease at a lower rate or a multidecadal drought occurs, additional (from 7% to 33%) water from energy-intensive sources will be needed. This will compromise the ability to reach safe-yield and increase energy demand for water up to 15%. In contrast, increasing the fraction of energy produced by solar power plants will likely guarantee safe-yield and reduce energy demand of 2%. This last solution, based on an expanded renewable portfolio and current trends of municipal and agricultural water demand, is also projected to have the most sustainable impacts on the three resources. Our analytical approach to model FEW interconnectivities quantitatively supports stakeholder engagement and could be transferable to other metropolitan regions.
Afficher plus [+] Moins [-]Ensuring water security, food security, and clean water in the North China Plain – conflicting strategies Texte intégral
2019
Wang, Shiqin | Hu, Yukun | Yuan, Ruiqiang | Feng, Wenzhao | Pan, Yun | Yang, Yonghui
The North China Plain (NCP) is a major food producing region in China. Overexploitation of groundwater for irrigation and overapplication of nitrogen (N) fertilizer have contributed to increased food production but have also resulted in water shortages and groundwater contamination. This paper reviews potential conflicts between strategies that ensure water security, food security, and water pollution reduction in the NCP. It outlines some agriculture-related strategies for resolving water shortages. Besides water saving and N saving technologies, policies such as fallow tillage, a water transfer project accounting for the recovery of groundwater level, and N management limiting N input in farmland are discussed. In particular, there are conflicts between the strategies for recovering shallow groundwater and releasing N from the unsaturated zone to the aquifer in the piedmont plain because a large amount of N is stored in the thick unsaturated zone. A transition from food-oriented strategies to sustainable development management of resources and the environment is necessary. To benefit from synergies and avoid tradeoffs between water security, food security, and clean water in the NCP, we must combine water and N management, groundwater level and water quantity control, socioeconomic issues, and climate change.
Afficher plus [+] Moins [-]An MCDM-based social network analysis of water governance to determine actors’ power in water-food-energy nexus Texte intégral
2020
Ghafoori Kharanagh, Samaneh | Banihabib, Mohammad Ebrahim | Javadi, Saman
A major water governance concern is how to coordinate the complex relationships of the water, food, and energy sectors and the resulting economic, social, and environmental consequences. Focusing on the challenges in one sector (e.g. water shortage in the water sector) and making decisions without considering other sectors will not solve these problems; rather, it will create a new problem (the decline of food production) in the food sectors. The nexus approach is a novel method to represent the interrelated challenges of the water, food, and energy sectors by considering the sectors’ policies to achieve sustainable development. The present study analyzes the social network of nexus actors in the Yazd-Ardakan aquifer, Yazd province, Iran. For this purpose, 54 partners in the nexus network were first identified in various public, private, semi-private and non-governmental organizations. Three types of interactions (knowledge and information exchange, budget transfer, and collaboration) were analyzed among the actors. The actor-network was, then, assessed at the levels of the entire network and individual actors. Then, a coherence analysis was performed by the density index at the entire network level, and the power analysis was carried out using in-degree, out-degree, betweenness, closeness, and eigenvector centrality indices at the individual actor level. Social network analysis criteria were, then, incorporated with the multi-criteria decision-making model ELECTRE I to select the key and powerful actors in the nexus network. Next, the powerful actors were identified and introduced with respect to 15 criteria employed in the social network analysis. According to the results, the power structure in the nexus network of the research area is not at equilibrium. Most of the power lies with the public sector. The water, food, and energy sectors act alone and they do not exploit their maximum organizational capacities to establish relationships with one another.
Afficher plus [+] Moins [-]Participatory Water-Food-Energy Nexus Approach for Evaluation and Design of Groundwater Governance Texte intégral
2021
Ghafoori-Kharanagh, Samaneh | Banihabib, Mohammad Ebrahim | Javadi, Saman | Randhir, Timothy O.
Improving the groundwater governance structure can help reduce groundwater decline and improve the state of an aquifer. This study develops an approach to modify groundwater governance based on a participatory, water-food-energy (WFE) nexus. Given the need for the participation of actors in the decision-making for the WFE nexus, we identified and selected some powerful nexus actors. Using the actor’s viewpoints, factors that led to excessive withdrawal of groundwater resources in each sector were identified as governance challenges. Using the DPSIR (Driving Force-Pressure-State-Impact-Response) approach, the actors assessed the cause-and-effect relationships of the groundwater governance challenges and proposed modification in the groundwater governance. Thirteen groundwater governance scenarios were defined. Then, the impact of scenarios on WFE sectors was evaluated by the participation of nexus actors and the nexus assessment ranking of the scenarios. The results show that, out of the 13 groundwater governance scenarios, only seven scenarios had positive effects in all three sectors (WFE). The scenario of developing and enforcing region-specific cropping patterns and value-chain management has the highest rank. This paper highlights the need for the participation of actors in decision-making and the use of WFE nexus in modifying the groundwater governance system.
Afficher plus [+] Moins [-]Urbanisation and emerging economies: issues and potential solutions for water and food security Texte intégral
2020
Kookana, R.S. | Drechsel, Pay | Jamwal, P. | Vanderzalm, J.
Urbanisation will be one of the 21st century's most transformative trends. By 2050, it will increase from 55% to 68%, more than doubling the urban population in South Asia and Sub-Saharan Africa. Urbanisation has multifarious (positive as well as negative) impacts on the wellbeing of humans and the environment. The 17 UN Sustainable Development Goals (SDGs) form the blueprint to achieve a sustainable future for all. Clean Water and Sanitation is a specific goal (SDG 6) within the suite of 17 interconnected goals. Here we provide an overview of some of the challenges that urbanisation poses in relation to SDG 6, especially in developing economies. Worldwide, several cities are on the verge of water crisis. Water distribution to informal settlements or slums in megacities (e.g. N50% population in the megacities of India) is essentially non-existent and limits access to adequate safe water supply. Besides due to poor sewer connectivity in the emerging economies, there is a heavy reliance on septic tanks, and other on-site sanitation (OSS) system and by 2030, 4.9 billion people are expected to rely on OSS. About 62–93% of the urban population in Vietnam, Sri Lanka, the Philippines and Indonesia rely on septic tanks, where septage treatment is rare. Globally, over 80% of wastewater is released to the environment without adequate treatment. About 11% of all irrigated croplands is irrigated with such untreated or poorly treated wastewater. In addition to acute and chronic health effects, this also results in significant pollution of often-limited surface and groundwater resources in Sub-Saharan Africa and Asia. Direct and indirect water reuse plays a key role in global water and food security. Here we offer several suggestions to mitigate water and food insecurity in emerging economies.
Afficher plus [+] Moins [-]A Systems Approach To Assess Trade Dependencies in U.S. Food–Energy–Water Nexus Texte intégral
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.
Afficher plus [+] Moins [-]Urbanisation and emerging economies: issues and potential solutions for water and food security
2020
Kookana, R.S. | Drechsel, Pay | Jamwal, P. | Vanderzalm, J.