An academic analysis with recommendations for water management and planning at the basin scale: A review of water planning in the Segura River Basin

Integrated water resource management in the Segura Hydrographic Basin: An artificial intelligence approach

Managing resources effectively in uncertain demand, variable availability, and complex governance policies is a significant challenge. This paper presents a paradigmatic framework for addressing these issues in water management scenarios by integrating advanced physical modelling, remote sensing techniques, and Artificial Intelligence algorithms. The proposed approach accurately predicts water availability, estimates demand, and optimizes resource allocation on both short- and long-term basis, combining a comprehensive hydrological model, agronomic crop models for precise demand estimation, and Mixed-Integer Linear Programming for efficient resource distribution. In the study case of the Segura Hydrographic Basin, the approach successfully allocated approximately 642 million cubic meters (hm3) of water over six months, minimizing the deficit to 9.7% of the total estimated demand. The methodology demonstrated significant environmental benefits, reducing CO2 emissions while optimizing resource distribution. This robust solution supports informed decision-making processes, ensuring sustainable water management across diverse contexts. The generalizability of this approach allows its adaptation to other basins, contributing to improved governance and policy implementation on a broader scale. Ultimately, the methodology has been validated and integrated into the operational water management practices in the Segura Hydrographic Basin in Spain.

Climate change impacts on temperate fruit and nut production: a systematic review

Temperate fruit and nut crops require distinctive cold and warm seasons to meet their physiological requirements and progress through their phenological stages. Consequently, they have been traditionally cultivated in warm temperate climate regions characterized by dry-summer and wet-winter seasons. However, fruit and nut production in these areas faces new challenging conditions due to increasingly severe and erratic weather patterns caused by climate change. This review represents an effort towards identifying the current state of knowledge, key challenges, and gaps that emerge from studies of climate change effects on fruit and nut crops produced in warm temperate climates. Following the PRISMA methodology for systematic reviews, we analyzed 403 articles published between 2000 and 2023 that met the defined eligibility criteria. A 44-fold increase in the number of publications during the last two decades reflects a growing interest in research related to both a better understanding of the effects of climate anomalies on temperate fruit and nut production and the need to find strategies that allow this industry to adapt to current and future weather conditions while reducing its environmental impacts. In an extended analysis beyond the scope of the systematic review methodology, we classified the literature into six main areas of research, including responses to environmental conditions, water management, sustainable agriculture, breeding and genetics, prediction models, and production systems. Given the rapid expansion of climate change-related literature, our analysis provides valuable information for researchers, as it can help them identify aspects that are well understood, topics that remain unexplored, and urgent questions that need to be addressed in the future.

Water footprint and virtual water trade analysis in water-rich basins: Case of the Chaohu Lake Basin in China

Water footprints and virtual water are widely used as essential tools for water use and conservation analysis of basins worldwide. Despite the importance of water-rich basins as the main force for water-saving, water use analysis has been mainly for water-scarce basins rather than water-rich basins in the existing literature. To fill the gap, in this paper, we investigate the water footprint and virtual water trade in a water-rich basin, namely the Chaohu Lake Basin in China, from 2007 to 2017 using input-output analysis. The results show that: (1) Water use efficiency in the Chaohu Lake Basin was significantly improved. The overall trend of the water intensity was declining, decreasing by 10.21 % in 2017 versus 2012; (2) The internal and external water footprints showed an upward trend, and the growth rate of total water footprint was 36.66 %; (3) The basin was a net virtual water exporter, but the net export flows of virtual water has decreased significantly. The virtual water net export flow decreased by 0.12 billion m³ in 2017 versus 2012; (4) Water resources in the basin were mainly used locally, and its supply to other provinces was minimal. Compared with some water-scarce basins such as the Heihe River Basin and Haihe River Basin, the Chaohu Lake Basin shows significant gaps in the virtual water export flow per capita and behaves differently in the proportion of virtual water transfer. Based on the above findings, we conclude with some guidance and implications for local governments and policymakers.

Multispecies fishways in a Mediterranean river: Contributions as migration corridors and compensatory habitat for fish

River connectivity is essential for the resilience of fish assemblages and populations and is a priority goal to reach good ecological status for river systems. Increasing knowledge on the functionality of restoration tools such as fishways is relevant for future management strategies. The present two-year assessment showed clear ecological contributions of different types of multispecies fishways in the fish assemblage of a strongly modified Mediterranean-type river. Just after their implementation, early and extended use by dominant river-resident fish of both naturelike and technical fishways were observed. All fishways were used in different seasons, especially during the migratory periods by potamodromous cyprinids, suggesting a possible use as migration corridors. Fishways also may provide compensatory habitats for small and juvenile individuals throughout the annual cycles, mostly for rheophilic fish inside nature-like bypasses and for limnophilics inside technical types. Fluvial habitat characteristics and lower flow variability inside the fishways could favour their role as a fish refuge, mainly to juveniles of cyprinids, in heavily regulated rivers where large flow fluctuations occurred. Nature-like fishways could be a better option to function as a compensatory habitat for rheophilic cyprinids in Mediterranean-type Rivers, even more because their use by large nonnative limnophilics seems to be very scarce. However, technical fishways could offer the opportunity to establish control traps of some nonnative fish, which could be of interest to reduce the risk of spreading invasive fish. Therefore, fish ecology and local hydrology should drive the decision between the types to implement. The obtained information on the ecological functionality of multispecies fishways should be considered for applying successful river restorations that are demanded by water and wildlife management schemes (e.g., the European Water Framework Directive).

Bibliometric Analysis of Groundwater’s Life Cycle Assessment Research

Groundwater is an important water resource that accounts for 30% of the world’s freshwater. 97% of this extracted groundwater is for drinking and human use. Due to anthropogenic activities, this resource is affected and, consequently, its life cycle is modified, changing its natural state. This paper aims to analyse the scientific production that deals with the study of groundwater’s Life Cycle Assessment (LCA), using bibliometric methods. Thus, it contributes to the evolution of knowledge of this resource in terms of its use (environmental, economic and social). The methodological process includes: (i) selection and analysis of search topics in the Scopus and Web of Science (WoS) databases; (ii) application of Bibliometrix and Visualisation of Similarity Viewer (VOSviewer) software to the data collected; (iii) scientific structure of the relation of the topics groundwater and life cycle, considering programme lines and relations in their sub-themes; (iv) literature review of Author keywords. A total of 780 papers were selected, 306 being from Scopus, 158 from WoS and 316 published in both databases. The time evolution of the analysed data (publications) indicates that groundwater LCA studies have seen exponential growth (between 1983 and 2021). In addition, it has three development periods: introduction (years between 1983 and 2001), growth (between 2002 and 2011) and maturation (between 2012 and 2021). At the country level (origin of contributions authors), the USA dominates the total scientific production with 24.7%, followed by Denmark with 12.8% and 10.3% for China. Among the main topics of study associated with LCA are those focused on: the proposal of remediation methods, the application and development of technologies and the use of water resources by the urban community. This study allows establishing new trends in agricultural development issues about irrigation efficiency, wastewater reuse, mining and treatment, climate change in a circular economy scheme related to sustainability and life cycle assessment.

Water Footprint and Virtual Water Trade of Maize in the Province of Buenos Aires, Argentina

Agriculture is the largest fresh water consuming sector, and maize is the most produced and consumed crop worldwide. The water footprint (WF) methodology quantifies and evaluates the water volumes consumed and polluted by a given crop, as well as its impacts. In this work, we quantified for the first time the green WF (soil water from precipitation that is evapotranspired) and the green virtual water exports of maize from Buenos Aires province, Argentina, during 2016–2017, due to the relevance of this region in the world maize trade. Furthermore, at local level, we quantified the green, blue (evapotranspired irrigation), and grey (volume of water needed to assimilate a pollution load) WF of maize in a pilot basin. The green WF of maize in the province of Buenos Aires ranged between 170 and 730 m3/ton, with the highest values in the south following a pattern of yields. The contribution of this province in terms of green virtual water to the international maize trade reached 2213 hm3/year, allowing some water-scarce nations to ensure water and water-dependent food security and avoid further environmental impacts related to water. At the Napaleofú basin scale, the total WF of rainfed maize was 358 m3/ton (89% green and 11% grey) and 388 m3/ton (58% green, 25% blue, and 17% grey) for the irrigated crop, showing that there is not only a green WF behind the exported maize, but also a Nitrogen-related grey WF.

Water Footprint and Virtual Water Trade: The Birth and Growth of a New Research Field in Spain

The growth in the number of studies applying and expanding the concepts of the water footprint and virtual water trade in Spain has generated a wealth of lessons and reflections about the scarcity, allocation, productive use, and management of water from the viewpoint of a semi-arid country. This paper reviews the evolution of this research field in Spain since its introduction in 2005 and reflects on its main contributions and issues of debate. It shows how these concepts can be useful tools for integrated water accounting and raising awareness, when used with certain precautions: (1) Supply-chain thinking, taking into account value chains and the implications of trade, generally ignored in water management, can help to address water scarcity issues and sustainable water use. (2) Green water accounting incorporates land use and soil management, which greatly influences hydrological functioning. (3) The grey water footprint indicator analyzes pollution from an ecosystem point of view and facilitates the understanding of the water quantity and quality relationship. (4) Apparent water productivity analysis, innovatively incorporated into Spanish studies, considers the economic and social aspects associated with water use. However, the decision-making context should be broader, contextualizing and complementing water information with other indicators.

Climate change impact on karstic aquifer hydrodynamics in southern Europe semi-arid region using the KAGIS model

Nowadays, there are many urban settlements in arid and semiarid areas supplied by groundwater from adjacent small aquifers. Climate projections with expected decreases in averages precipitation values jointly with increases in the frequency of heavy rainfall events does not show a clear pattern to how water resources in karstic aquifers are going to evolve. This paper, focused in the province of Alicante (Southeast of Spain), assesses the behaviour of a small karstic aquifer, the Mela aquifer, whose resources supply urban water consumption for close municipalities. We assess the hydrogeological response of the aquifer, through the KAGIS black-box GIS-based model, for the present climate conditions and for the long period analysing the four scenarios provided by the International Panel of Climate Change. Main results prove that, if we do not diminish the greenhouse gas emissions, the climate change impact on the hydrological response of the study aquifer shows a decrease in the flow rate from its unique spring and will be non-existent during the summer months. So, it will be necessary to design supply strategies for these municipalities and to carry out them, meeting budget restrictions and avoiding potential water shortages.

Assessing adaptation measures on agricultural water productivity under climate change: A case study of Huai River Basin, China

This study explored an integrated framework to assess the effectiveness of adaptation measures on the water productivity (WP) of the agricultural water management (AWM) system in the Huai river basin of China considering climate change impact. The adaptation measures include optimization of cropping pattern (OCP) and upgradation of irrigation techniques (UIT). The delta change method was used to downscale the climate variables from RCP4.5 and RCP8.5 of general circulation models (GCMs) during 2021-2050, the water footprint theory was used to estimate the spatial distribution of blue water to calculate the WP, and the nonlinear optimization model was used to seek optimal cropping pattern aiming at maximizing the system's WP. The changes in WP due to climate change and adaptation measures (e.g. combinations of OCP and UIT) were compared. Results indicated that WP under RCP4.5 and RCP8.5 would be 4.56% and 6.51% lower than those under the benchmark scenario, respectively. The mitigation rates to the negative impact of climate change on WP under RCP4.5 and RCP8.5 would be (1) 3.05% and 3.37% for the combination of spay irrigation technique and OCP, and (2) 4.34% and 4.59% for the combination of drip irrigation technique and OCP, respectively. It was revealed that the combination of drip irrigation and cropping pattern optimization could largely offset the adverse effect from climate change on WP under RCP4.5. Under such a scenario, the total plant areas of wheat and maize would reduce over the basin and so would the net export of crops in the basin; this would lead to a decrease in the crop trade benefit of 7.07 × 10⁹ $ and a relief of 7.50 × 10⁹ m³ of blue water loss. This study results could offer strategic decision support for long-term sustainable AWM of Huai river basin in a changing environment.

Wastewater Treatment and Water Reuse in Spain. Current Situation and Perspectives

The issues of wastewater treatment and the reuse of water are of great importance, especially in areas where the shortage of conventional resources is a structural problem, as it is in the case of Spain. Wastewater reuse is a valid mechanism to avoid problems derived from droughts and water scarcity. It allows access to water resources in areas with water restrictions and to prevent futures scenarios, due to it being expected that water consumption will double by 2050 over the world. Thus, the likelihood that this unconventional, strategic resource would become scarce is unquestionable, particularly in cases where water planning and exploitation systems prioritize the preservation, protection, and improvement of water quality, as well as the sustainable and efficient use of natural resources. This paper shows how wastewater treatment and reuse are linked, as the reuse of wastewater is associated with a previous regeneration, and both of them are essential tools for maximizing environmental outcomes, as called for in the European Union Directives.

Assessing Water Shortage through a Balance Model among Transfers, Groundwater, Desalination, Wastewater Reuse, and Water Demands (SE Spain)

Currently, water demands are increasing notoriously, spreading the pressure on available water resources around the world in both quantity and quality. Similarly, the expected reduction of natural water inputs, due to climate change, depicts a new level of uncertainty. Specifically, Southeast Spain presents water scarcity due to its aridity—irregular and scarce precipitation and high evapotranspiration rates—combined with the competition between several water demands: environment, agricultural dynamics, urban-tourist activities, and industry. The study area of this work is the most relevant functional urban area of Alicante province (SE Spain), where the administration of water management is carried out by a range of authorities at different levels as the consequence of a complex historical development of water governance schemes: at the national, regional, and local levels. This study analyzes 21 municipalities and proposes a conceptual model which was developed by including different origins of water inputs—surface resources, groundwater, desalination, wastewater reuse, or interbasin transfers—and water demands with information obtained from 16 different sources. Our main results denote a relevant water deficit of 72.6 hm3/year even when one of the greatest rates of desalinated water and reused wastewater in Europe are identified here. This negative balance entails restrictions in urban development and agricultural growth. Thus, presented results are noteworthy for the water policy makers and planning authorities, by balancing the demand for water among various end users and providing a way for understanding water distribution in a context of scarcity and increasing demand, which will become one of the most challenging tasks in the 21st century.