The agricultural community has a challenge of increasing food production by more than 70% to meet demand from the global population increase by the mid-21st century. Sustainable food production involves the sustained availability of resources, such as water and energy, to agriculture. The key challenges to sustainable food production are population increase, increasing demands for food, climate change, and climate variability, decreasing per capita land and water resources. To discuss more details on (a) the challenges for sustainable food production and (b) mitigation options available, a special issue on “Water Management for Sustainable Food Production” was assembled. The special issue focused on issues such as irrigation using brackish water, virtual water trade, allocation of water resources, consequences of excess precipitation on crop yields, strategies to increase water productivity, rainwater harvesting, irrigation water management, deficit irrigation, and fertilization, environmental and socio-economic impacts, and irrigation water quality. Articles covered several water-related issues across the U.S., Asia, Middle-East, Africa, and Pakistan for sustainable food production. The articles in the special issue highlight the substantial impacts on agricultural production, water availability, and water quality in the face of increasing demands for food and energy.

In this review paper we focus on the dilemma of whether or not current fresh water supply will meet the demand/needs of agricultural crops despite the continuing impact of water scarcity. In addition, we evaluate whether an increase in future population, change in water demand and supply patterns, due to climate change, will allow sustainable food production. With increased scarcity of freshwater, new water conservation technologies and biotechnology were developed, as well as newly developed water sources such as recycled wastewater, and various water institutions, which may help ease water scarcity. With new advancements in farming practices and crop innovations global food supply is still challenged by climate change effects on both water and land resources used for food production.

Water, energy, and food security are of critical concern as rising population growth and rapid urbanization place greater pressure on our natural resources. The trade of ‘virtual water’ through agricultural products and its appropriation through foreign direct investment (FDI) in food production have emerged as potential strategies for water-scarce countries seeking food security. In Saudi Arabia, where domestic agricultural enterprise remains a state priority despite extreme water scarcity, a shift to overseas food production to meet domestic demand could have significant implications for water and energy use as well as local labor markets. This study evaluates the growing internationalization of food production in water-scarce countries using the case of Saudi Arabia as a microcosm to illustrate the tradeoffs in resource consumption associated with crop selection and farming practices. This analysis indicates that the implications of different types of large-scale agribusiness must be more explicitly accounted for in government policy given the non-renewable nature of groundwater and energy. This work also quantifies the increase in the import of virtual water through conventional trade, which has significant potential to minimize groundwater pumping for food production in arid environments. A brief, complementary assessment of the growing role of FDI shows that further analysis is needed to ascertain the long-term resource impacts of direct investment in overseas enterprise and to minimize potentially negative impacts on water access and rural livelihoods in target nations. Active engagement of local communities and/or more holistic investment in infrastructure or improving agricultural productivity could also help avoid the potential for conflict and contribute towards long-term sustainability.

Food processing is among the greatest water‐consuming industries with a significant role in the implementation of sustainable development goals. Water‐consuming industries such as food processing have become a threat to limited freshwater resources, and numerous attempts are being carried out in order to develop and apply novel approaches for water management in these industries. Studies have shown the positive impact of the new methods of process integration (e.g., water pinch, mathematical optimization, etc.) in maximizing water reuse and recycle. Applying these methods in food processing industries not only significantly supported water consumption minimization but also contributed to environmental protection by reducing wastewater generation. The methods can also increase the productivity of these industries and direct them to sustainable production. This interconnection led to a new subcategory in nexus studies known as water‐food‐environment nexus. The nexus assures sustainable food production with minimum freshwater consumption and minimizes the environmental destructions caused by untreated wastewater discharge. The aim of this study was to provide a thorough review of water‐food‐environment nexus application in food processing industries and explore the nexus from different aspects. The current study explored the process of food industries in different sectors regarding water consumption and wastewater generation, both qualitatively and quantitatively. The most recent wastewater treatment methods carried out in different food processing sectors were also reviewed. This review provided a comprehensive literature for choosing the optimum scenario of water and wastewater management in food processing industries.

Food sovereignty is the rights of every nation to maintain and develop skills in producing basic foods, with respect for cultural and product diversity. The food sovereignty of a nation would be viable provided that the natural resources essential for plant growth are available and one of them is water. However, the increase of water demand far exceeds its availability, thus water shortage for agriculture with, as water is also needed by other organisms. As a tropical country, Indonesia has sufficient water supplies from both rainfall and groundwater. With good water management and conservation strategy, it should suffice the demand. Therefore, save the water movement as part of water sustainability program would highly contribute in achieving sustainable food production hence food sovereignty in the long run.

Urban agriculture is booming. During case study Water-Energy-Food nexus research at urban farms, investigation indicated two types of ‘food’ to be relevant for urban agriculture. Consequently, the ‘food’-component in the WEF nexus is split, which leads to a Water-Energy-Nutrients-Food (WENF) nexus framework for urban farming. This systematic WENF nexus monitoring, analysis and evaluation framework aims to facilitate acquisition of quality data during case study research at farming sites, in order to fill the quantitative data gap regarding urban agriculture and closed circularity loops. Stocks of various types of water, energy, nutrients and food are differentiated and flows within each described. Subsequently, multi-sectoral flows between the four main resource stocks and their interactions and interdependencies are identified with the aim of formulating options for circularity in urban farming. The analysis shows that urban systems offer many opportunities for the realisation of sustainable agriculture in cities because waste management and farming could mutually reinforce each other. Local reuse of resources found in urban “waste” has the potential to reduce stormwater nuisances, energy needs for water, nutrient and food transport, irrigation, and wastewater pumping while eliminating the need for synthetic soil improvement and unsustainable mineral mining. All in all, reusing resources from urban (waste)waters in urban farming initiatives can reduce the negative impact of food production on the environment.

This study investigates the possibilities of applying water generated from the atmosphere for agricultural processes, particularly hydroponic systems. A solar powered, off-grid greenhouse system is proposed as a theoretical solution to food production, in areas affected by water scarcity. Two experiments are conducted with the purpose of testing atmospheric water quality and how it performs in a hydroponic setting. The plausibility of powering said greenhouse system using solar energy is investigated, considering several available solar technologies. Ultimately, the footprint area required to install enough capacity to power the system is discussed, and the potential site of such a system is modelled and visualized. The experiments concluded that atmospheric water is likely suitable for hydroponic use. The study also found that the footprint area required for the greenhouse system probably can be considered reasonable for certain applications, but more research and advances within solar power technology would be beneficial | <p>2021-06-08</p>

If a decision is made at the national level to increase the share of bioenergy, what implications does this have for water, land and energy? How do electricity subsidies contribute to groundwater depletion and what can be done about it? How can we ensure that sectoral policies and strategies consider the potential trade-offs for other sectors? Finding answers to these questions is the main challenge of the Water-Energy-Food Nexus. By describing the complex and interrelated nature of our global resource systems, the Nexus approach helps us to better understand and systematically analyze how we can use and manage our resources in light of different, often competing interests and goals.