Increasing pressure from population growth and climate change has placed various challenges to urban systems concerning the sustainable supply and use of food, energy and water. To achieve the synergistic and sustainable management of food, energy and water demand, the inter-linkages between the three subsystems should be explored. Taking Beijing as the case study reproducible in a like manner for other urban systems, this research aims to develop a household Food-Energy-Water (FEW) nexus dynamic model to explore the influence of various factors on the end-uses. Three main innovation points are included in this research. Firstly, long-term simulations from 2010 to 2050 can be provided in this model to quantitatively estimate climate change potential under possible management strategies. Secondly, three different levels of influencing factors of household resource consumption are included in this model at the same time, including individual level (behaviors), household level (appliances) and government level (resource prices). Thirdly, multiple scenarios combinations are analyzed in this research. The results demonstrate the complex interconnections among the household food-energy-water uses. What’ more, short-term effects, lag effects as well as lock-in effects can influence the policy effectiveness, so that policy combinations or complements are needed to enhance the effects.

Rice production not only consumes large amounts of irrigation water and fertilizer, but also poses a high risk of water pollution by delivering nitrogen (N) through surface runoff. To ensure sustainable rice production, many water-saving irrigation managements have been proposed and implemented, but drainage water managements receive far less attention and need to be further explored. This study aimed to determine the paddy drainage optimization management and assess its potential to water and food security in China via different scale methods (from pot and field experiments to national assessment). The national investigation of water and N fertilizer use in paddy fields implied that diffuse N pollution was expected to continue increasing, especially in the Yangtze river basin. Two-years field experiments at typical sites identified that the tillering and jointing–booting stages were critical risk stages for N runoff loss, and pot experiments on the critical stages were conducted to determine the optimal drainage water level without yield reduction. Then, the applicability of paddy drainage optimization was verified and evaluated by drainage optimization field experiment and precipitation characteristics analysis. Finally, the potential of drainage optimization on mitigating N runoff loss was estimated by scenario analysis at the national scale. After implementing paddy drainage optimization in field experiments, surface runoff and nitrogen runoff loss decreased by 27.97–78.94% and 35.17–67.95%, respectively, without affecting rice yield. By full implementation of the optimal drainage and fertilization management, N runoff loss could be reduced by 0.19 Tg yr⁻¹ at the national scale. These results suggest that paddy drainage optimization is an agro-ecosystems friendly water management for sustainable rice production, and has notable potential to ensure water and food security in China.

The application of potassium bromate in the baking industry is used in most parts of the world to avert the human health compromise that characterizes bromates carcinogenic effect. Herein, various methods of its analysis, especially the electrochemical methods of bromate detection, were extensively discussed. Amperometry (AP), cyclic voltammetry (CV), square wave voltammetry (SWV), electrochemiluminescence (ECL), differential pulse voltammetry and electrochemical impedance spectroscopy (EIS) are the techniques that have been deployed for bromate detection in the last two decades, with 50%, 23%, 7.7%, 7.7%, 7.7% and 3.9% application, respectively. Despite the unique electrocatalytic activity of metal phthalocyanine (MP) and carbon quantum dots (CQDs), only few sensors based on MP and CQDs are available compared to the conducting polymers, carbon nanotubes (CNTs), metal (oxide) and graphene-based sensors. This review emboldens the underutilization of CQDs and metal phthalocyanines as sensing materials and briefly discusses the future perspective on MP and CQDs application in bromate detection via EIS.

The water-energy-food (WEF) nexus has motivated several studies, opening space to provide robust support for the decision-making process. Certain studies seek to understand the interdependence of these three resources in a quantitative and/or qualitative manner, usually using total water, energy, and food indicators. However, in times of social, economic, and environmental crisis, national policies must be optimized, and hence it is necessary to evaluate marginal and critical indicators of each resource, i.e., sensitive indicators. Based on these indicators, we propose a methodology for assessing ecological efficiency (eco-efficiency) in industries using a multiregional input-output table, Data Envelopment Analysis, and the Malmquist index, with the main objective of internalizing normally overlooked impacts in the national policymaking process. For this, we present a quantitative assessment of the WEF nexus in the Brazilian food and beverage industry, since it is one of the pillars of the country's economy and has several positive and negative effects related to the WEF nexus, as well as a growth trend to meet rising food demand. From 2015 to 2019, this industry eco-efficiency was evaluated in terms of water stress, fossil energy consumption, and financial compensation to low-skilled workers. The main findings show that the Fish industry has the highest average eco-efficiency, with sustainable gains over the period, while the Meat cattle industry has the lowest average eco-efficiency. As a result, the Fish industry places less strain on these resources to generate the same socioeconomic benefits as others, resulting in less food and water insecurity, and should be prioritized in Brazil's national policies regarding industry expansion. We conclude that this methodology can help integrate WEF resources into national policy decision-making processes, allowing the identification of negative impacts that should be avoided or mitigated, as well as positive impacts that should be encouraged.

The current water shortage in China is critical. Moreover, the water shortage has become the main bottleneck hindering sustainable economic growth. Against the background of China’s dual control target of total water use and intensity, we choose the Yangtze River Delta (YRD) region as a research object, which encompasses Shanghai, Jiangsu, Zhejiang, and Anhui. Based on the perspective of water-energy-food nexus, we employ the generalized Divisia index method to decompose the change of water use into eight factors, regional economic scale effect, regional energy use scale effect, regional food production effect, regional water technology effect, regional energy technology effect, regional water-energy nexus effect, regional food-energy nexus effect, and regional water technology for food production effect, and analyze the contribution of each driver to identify the key drivers of total water use control. The results showed that the top four influencing factors are GDP, water intensity, energy consumption, and water-energy nexus in the YRD region. Regional economic scale is the first driving factor for increasing water use in the YRD region except for Zhejiang. Water intensity is the primary driving force of water-saving in Zhejiang. Energy consumption is the third driver of increasing water use in Jiangsu and Anhui. The effect of water-energy nexus is the third driving factor that affects the change of water use in Shanghai and Zhejiang. The authorities in the YRD region should vigorously develop water and energy utilization technologies to increase the water intensity and decrease energy consumption. The energy sector should decrease the water use to decrease the water-energy nexus which is also the main driving factor affecting the change of water use.

Identifying the critical socioeconomic drivers of food-related scarce water uses at the provincial level is conducive to the formulation of region-specific policies. However, existing studies have not quantified the effects of regional socioeconomic factors on food-related scarce water uses in China. This study used the environmentally extended multi-regional input-output analysis and structural decomposition analysis to explore the socioeconomic determinants for the changing food-related scarce water uses in Chinese regions during 2007–2012. The results showed that the decrease of scarce water use intensity in the North Coast and Northwest (e.g., Hebei and Xinjiang) is the most effective way to reduce scarce water uses, contributing 11.5 and 11.4 billion tons of scarce water use reductions, respectively. It is also critical for Hebei, Shandong, Henan, and Xinjiang to focus on the improvement of local production structures. Moreover, reducing excessive food consumption and optimizing dietary patterns in developed coastal regions (e.g., Guangdong and Shanghai) can effectively reduce national water scarcity. For example, 4% reduction of the food consumption level in Guangdong would lead to 11% reduction of induced scarce water uses. Furthermore, it is essential to consider the interprovincial trade in food-water-related policy-making. The strengthening of interregional cooperation is also highlighted for sustainable food and water resource management in China.

As the basis for virtually any form of nitrogen fertilizers, ammonia plays a vital role in agriculture; in addition, there has been an increased interest in its use as a carbon-free energy carrier. However, ammonia is also associated with two major environmental concerns: CO₂ emissions from the conventional production process and nitrogen pollution from the excessive use of ammonia-based fertilizers. To mitigate these environmental impacts, we develop an optimization framework for the design of a sustainable ammonia-based agricultural system that synergistically integrates the production of ammonia from renewable resources and effective measures for nitrogen management. The proposed model captures the effect of intermittency by incorporating both design and detailed operational decisions. By applying a multiscale time representation that reduces the problem size and a tailored surrogate model that accurately approximates model nonlinearity, we are able to achieve optimal solutions within reasonable computation times. A computational case study is conducted using real-world data from a local farm in Morris, Minnesota, and the results indicate the trade-off between cost and nitrogen loss. Importantly, we show that practicing effective nitrogen management can significantly reduce the nitrogen loss with only a small increase in net present cost.

In face of the interdependencies between policy areas in the management of common pool resources, studying nexus challenges is insightful for the exploration of new governance strategies. This includes the co-occurrence of and the interaction between different governance modes. We put forward the argument that a promising approach to explore these dynamics over time is the method of discourse network analysis. By conducting a discourse network analysis of German agricultural and water policy in a region with intensive livestock farming and large surpluses of manure that exert pressure on water and soil resources, we analyse the development of discourses within and across policy areas. We show that the analysis of public discourses contributes to the understanding of coordination between actors.