The main challenge faced by agriculture is to produce enough food for a continued increase in population, however in the context of ever-growing competition for water and land, climate change, droughts and anthropic water scarcity, and less-participatory water governance. Such a context implies innovative issues in agricultural water management and practices, at both the field and the system or the basin scales, mainly in irrigation to cope with water scarcity, environmental friendliness, and rural society welfare. Therefore, this special issue was set to present and discuss recent achievements in water, agriculture, and food nexus at different scales, thus to promote sustainable development of irrigated agriculture and to develop integrated approaches to water and food. Papers cover various domains including: (a) evapotranspiration and crop water use; (b) improving water management in irrigated agriculture, particularly irrigation scheduling; (c) adaptation of agricultural systems to enhance water use and water productivity to face water scarcity and climate change; (d) improving irrigation systems design and management adopting multi-criteria and risk approaches; (e) ensuring sustainable management for anthropic ecosystems favoring safe and high-quality food production, as well as the conservation of natural ecosystems; (f) assessing the impact of water scarcity and, mainly, droughts; (g) conservation of water quality resources, namely by preventing contamination with nitrates; (h) use of modern mapping technologies and remote sensing information; and (i) fostering a participative and inclusive governance of water for food security and population welfare.

Editorial | The main challenge faced by agriculture is to produce enough food for a continued increase in population, however in the context of ever-growing competition for water and land, climate change, droughts and anthropic water scarcity, and less-participatory water governance. Such a context implies innovative issues in agricultural water management and practices, at both the field and the system or the basin scales, mainly in irrigation to cope with water scarcity, environmental friendliness, and rural society welfare. Therefore, this special issue was set to present and discuss recent achievements in water, agriculture, and food nexus at di erent scales, thus to promote sustainable development of irrigated agriculture and to develop integrated approaches to water and food. Papers cover various domains including: (a) evapotranspiration and crop water use; (b) improving water management in irrigated agriculture, particularly irrigation scheduling; (c) adaptation of agricultural systems to enhance water use and water productivity to face water scarcity and climate change; (d) improving irrigation systems design and management adopting multi-criteria and risk approaches; (e) ensuring sustainable management for anthropic ecosystems favoring safe and high-quality food production, as well as the conservation of natural ecosystems; (f) assessing the impact of water scarcity and, mainly, droughts; (g) conservation of water quality resources, namely by preventing contamination with nitrates; (h) use of modern mapping technologies and remote sensing information; and (i) fostering a participative and inclusive governance of water for food security and population welfare | info:eu-repo/semantics/publishedVersion

Northeast Farming Region of China (NFR) produces about one-third of the national maize output. Shortage of crop irrigation water is one of the main threat to the stable level of maize production in the NFR. Previous studies on the sensitivity of maize production to drought are typically based on field experiments and treat the maize growing season as a whole, with rare attention to the varying impacts of drought across different maize growth stages. Given the importance of NFR on China’s food security, it is crucial to optimize the irrigation schedule to mitigate the adverse effects of drought. In this study, we employ Agro-ecological Zone (AEZ) model to investigate how climate change affects irrigation water requirement (IWR) of maize during different growth stages and under different climate change scenarios. Results indicate that the NFR would experience a substantial increase in the probability of extremely shortage of crop irrigation water under future climate change. The ensemble simulation under future climate projections indicates more frequent demands for irrigation with substantially increased amount in the mid-season stage (G3) when maize is more sensitive to water deficit compared with other stages. These findings indicate that earlier planning of irrigation infrastructure and development of more efficient irrigation scheme and technologies is of great importance to secure maize production in the region.

In the tropics, the water potential of a region cannot be adequately assessed from precipitation alone due to the seasonal character of rainfall and even more so owing to the changing climate scenario. It is therefore necessary that in any agro-climatological program, there must be a clear understanding of the actual amount of water that evaporates and transpires (AET), and the amount of water that would evaporate and transpire if water were always readily available (PET). This could be done through the method of the water balance. The present work examines the water budget of parts of the Imo river basin and its implications for improved crop production through supplementary irrigation schedules. It was observed, that the study area is already facing moisture-stress. This is because even during rainy months supplementary irrigation is required to compensate for the occasionally moisture deficit due to increased evapotranspiration. The study showed that cultivation of maize, rice and tomatoes can be carried out on an all-year round basis under a scientific irrigation scheme. Thus the study provided farmers with guideline on the period and quantity of water required for supplementary irrigation, a development which will prevents wilting of plants before the application of needed water.

In the process of urban agglomeration, water-food security can be deemed as a key to support urban development and human living, but which can be challenged by expanded population growth, accelerated industrialization, unbalance regional economic development and diversity of weather (due to climate changes). In this study, a water resources allocation and food production (WF) optimization is developed for regional sustainability under multiple uncertainties. A hybrid two-stage fuzzy programming with Laplace criterion (TSFL) is proposed into a WF optimization to handle hybrid indeterminacies, which can increase the robustness of decision-making. The WF optimization with proposed TSFL method can be applied to a practical case of Beijing-Tianjin-Hebei (BTH) region. The obtained results associated with water deficits, optimal water allocations, inadequate capacities of food production, rational irrigation schedules, sound livestock scales, optimized agricultural possessing layouts and system benefits under various population-economy regulation scenarios can be obtained. The results can reflect the tradeoff between economic development and water-food safety; meanwhile, they can display risk violation of WF plan under various credibility levels and Laplace criterions (based on TSFL method). All above results can facilitate to produce an optimized water-food plan to support the synergetic development of BTH region in a robust manner.