Water Demand Management Models in Agriculture: A Literature Review

Effective water management is essential for achieving sustainability amid rising demand and the challenges posed by climate change [1]. The impacts of climate change are linked to an increase in the frequency and intensity of extreme weather events, such as floods and droughts. Integrated Water Resources Management (IWRM) serves as a key strategy to address this challenge through improved planning and allocation of water resources, particularly during periods of heightened climate variability [2].

Water management is a global concern, as this resource is essential for human survival and economic, social, and environmental activities. Beyond its role in public well-being, water is an element in maintaining ecosystem stability, regulating climate patterns, supporting biodiversity, and sustaining agricultural and industrial production. The growing demand for freshwater, coupled with the increasing impacts of climate change, highlights the urgency of adopting integrated and sustainable management strategies.

In developing countries across continents such as Asia, Africa, and Latin America, particularly in regions facing water scarcity, water management is severely compromised by anthropogenic factors that negatively impact both the quantity and quality of available resources. Industrial and agricultural discharges, linked with rapid population growth and urban expansion, aggravate water pollution and overexploitation. These challenges not only threaten water security but also intensify socio-economic inequalities and environmental degradation [3].

Addressing these issues requires a multifaceted approach that includes community participation, the implementation of strong water policies, and transboundary cooperation. Strengthening regulatory frameworks, investing in infrastructure for water treatment and distribution, and promoting conservation initiatives are essential steps toward ensuring a more equitable and resilient water management system. Without immediate action, the consequences of poor water governance will continue to escalate, further risking global sustainability [4].

In response to these challenges, innovative strategies have been developed to optimize water planning, distribution, and utilization. These management models aim to ensure water security, a concept that encompasses resource availability, equitable access, and adequate quality for various uses. Water security is crucial for reducing community vulnerability to scarcity, promoting sustainable development, and mitigating conflicts arising from unequal distribution.

However, achieving efficient water management remains a complex challenge. Factors such as climate change, population growth, and evolving water demands make resource planning and modeling increasingly difficult. Additionally, each region faces unique conditions that influence water availability, necessitating adaptive approaches and context-specific strategies [5].

The need for actions to improve water management efficiency is evident from data showing that while the global population has tripled over the last century, water consumption has increased six times [6]. The competition for water availability is a growing issue, particularly in regions where water resources are limited, leading to conflicts among various water users [7]. Irrigated agriculture, one of the largest water consumers, is especially vulnerable to poor management and planning [8]. In Latin America, particularly in Mexico, agriculture is estimated to consume up to 76.3% of available freshwater [9]. Thus, agricultural development must be sustainable, balancing soil and water use to maintain environmental system quality without compromising long-term agricultural productivity [10]. IWRM must be grounded in a holistic approach that harmonizes social, environmental, and economic dimensions. This entails designing water management models that prioritize the preservation of water availability for future generations while simultaneously promoting social well-being through equitable access to the resource, protecting associated aquatic and terrestrial ecosystems, and fostering sustainable economic development [11].

Despite growing scientific attention to water assignment, research tends to focus on economic aspects, overlooking environmental and social factors essential for sustainable development [12]. The objective of this study is to analyze scientific production related to water management models and their implementation in the agricultural sector, to determine whether this research has incorporated IWRM approaches to promote more sustainable and efficient water management. This study aims to guide water management model planning for sustainable agricultural development, demonstrating how scientific research has evolved from considering one or two aspects of water management to adopting a holistic perspective aligned with IWRM's triad of approaches which are social equity, economic efficiency and environmental sustainability [13].

The systematic literature review on water management models was based on the following question using the PICOT search strategy, which structures searches effectively and establishes research boundaries [14]: How have water management models evolved over time and whether their implementation in the agricultural sector has complied with IWRM principles, comparing Latin America with other regions? In addition to this central question, three complementary questions were derived: What is the main measurement scale in the evaluation or planning of water management models? What types of models predominate in the development of water management? And which countries conduct the most research on water management? These auxiliary questions helped contextualize and deepen the understanding of different approaches and advances in global water management.

Latin America was selected as the focus of this study because, as in the rest of the world, water resources are essential for regional development. Additionally, the region faces significant challenges in scientific development, particularly in the production and dissemination of high-quality research. Among the main limitations is restricted access to funding, which hinders the ability to conduct comprehensive studies and reduces opportunities for publication in high-impact journals [15].

This situation is further exacerbated by political instability, which influences government support for institutions and affects the availability of funds and resources for research [16]. In this context, understanding how scientific progress develops and its scope in a critical issue such as water management is essential for this study.

The PRISMA method was used to guide the research, ensuring transparency and replicability in each phase [17]. The databases selected for the search were SCOPUS and Web of Science (WOS); these two databases were selected over the others due to their reliability and coverage, as well as their ability to provide a controlled search environment. While Google Scholar offers a broader range of publications, it also contains a significant amount of grey literature and non-peer-reviewed material. In the database selected using the equation and keywords described in Table 1. The choice of these keywords aimed to identify primarily agricultural regions, a sector that belongs to the primary group and is the largest consumer of blue water [18]. The term 'blue water' refers to surface and groundwater stored in aquifers, lakes, reservoirs, and other bodies with water available for use [19]. Additionally, the problem of water scarcity and its counterpart, water security, were considered within the framework of water management models.

In identification phase, inclusion and exclusion criteria were defined as the first filter to guide the selection of relevant publications for the study. The inclusion criteria selected only scientific articles that contained at least one search term in the title, abstract, and/or keywords, and were written in English or Spanish. The exclusion criteria ruled out review articles, book chapters, books, conference papers, and articles without full access. Only journal articles were selected due to the quality and rigor with which scientific contributions are reviewed. While conference papers have greater dissemination, they typically have lower rejection rates and focus on newness and research clarity, often undergoing single-blind review [20]. Our primary reason for this selection is to analyze the evolution of management models over time rather than just their innovations.

The literature review focused exclusively on the two most widely used languages in scientific production in Latin America and internationally, facilitating comparisons with studies from other regions. While Brazil is the country with the highest scientific output in the region, both in this and other fields [21], the lack of proficiency in Portuguese led to the exclusion of articles in this language. This decision aims to minimize potential biases that could compromise the interpretation of key concepts while translating texts.

From the articles obtained in the previous process, in the screening phase the abstract and methodology were reviewed to ensure that the study considered at least one of the three approaches governing integrated water management models, thereby limiting the review to studies relevant to the research (Figure 1). The results were excluded during the screening process because, after reviewing the abstracts of the articles, the application of water management models was not identified. Specifically, we refer to studies that assess water use in an economic sector and include variables associated with the IWRM framework to meet its concept. Consequently, studies focusing solely on the impact of climate variability, land use, and water quality were discarded.

The metadata from the selected publications were compiled in a spreadsheet, including the title and year of publication, each assigned a unique identifier (ID). Relevant data were extracted from the articles, such as the country where the study was conducted, the variables evaluated, the type of model used, the scale of analysis, and the IWRM framework to which the model belongs to (social equity = social; economic efficiency = economic; environmental sustainability = environmental). Additionally, the level of water stress or the index Falkenmark was obtained for each country, based on the data presented by Ruess (2015), which relies on population figures from 2002. This indicator defines the total renewable water resources available per capita in a given region and classifies water availability (D) into the following categories: Extreme Scarcity (D < 1,000 m³/capita/year), Critical Scarcity (1,000 ≤ D < 1,700 m³/capita/year), Low Availability (1,700 ≤ D < 5,000 m³/capita/year), Medium Availability (5,000 ≤ D < 10,000 m³/capita/year), and High Availability (D > 10,000 m³/capita/year) [23].

Cross-analyses between variables were performed to answer secondary questions, such as identifying the predominant scale of evaluation, the evolution of water management research and its recurring focus in studies and analyzing the link between countries with water issues and their scientific output.

In this systematic review analysis, studies were categorized based on the type of model used. Models classified as "Tools" are those used for the simulation, analysis, or optimization of water supply and demand. Another category, "Water Policy" focuses on developing and implementing policies and regulatory frameworks for water management. Lastly, models classified as "Practice" refer to specific methods applied in targeted locations to enhance the efficiency and sustainability of water supply.

Ultimately, a bibliometric analysis was conducted on keywords related to water management models, with a specific focus on the agricultural sector. For this purpose, a bibliometric network map was used to graphically represent the interconnections among the reviewed studies, thought VOSviewer software [24].

The 44% of studies used the basin as analysis scale (Figure 2), which is the accepted management unit for the development of water strategies [25, 26]. Watershed delineation is a key mechanism in water governance, as it enables resource management through an approach that considers the specific environmental and social conditions of each territory. This framework helps the participation of various stakeholders in decision-making processes, including local communities, governmental agencies, and civil society organizations. By aligning management strategies with the natural hydrological boundaries, this approach promotes a more integrated and sustainable use of water resources.

However, despite its advantages, watershed-based delineation can lead to conflicts when natural boundaries do not align with jurisdictional divisions established by governmental entities. In many cases, administrative and political frameworks are based on criteria that do not necessarily reflect the natural dynamics, resulting in overlapping authorities, discrepancies in resource allocation, and challenges in interinstitutional coordination. These discrepancies can hinder effective water management and create tensions among different governance levels.

To address these challenges, it is essential to develop governance strategies that foster cooperation among jurisdictions and promote integrated management mechanisms. Strengthening coordination between local, national, and international stakeholders can contribute to a more equitable and efficient distribution of water resources, reducing conflicts and enhancing long-term sustainability [27].

The remaining 38 articles are distributed across five different types, such as cities, irrigation districts, worldwide, country, and regional scales. In another analysis, it was found that over 50% use models as Tools, the most frequent category, 28% employ them as practices, and the remaining 21% use them as policies. This result could be associated with the screening process applied in Prisma, where conferences and books were excluded, and gray literature, which often addresses public policy topics in informational resources, was not considered.

The representation of scientific production on water management was cross-referenced with the number of publications per country, and evaluated using the Falkenmark indicator [28], which assesses surface runoff and population data from 2002.

The analysis of 68 publications reveals references to 23 different countries, with 21 studies focusing on nations in Asia (Figure 3). According to the Falkenmark indicator, Indonesia is the only country not classified as water-stressed, while all others face absolute water scarcity. Europe follows in publication count, with 16; however, the Falkenmark indicator shows that most countries in this continent face water scarcity, except for Greece, which is at a low level of water stress. The Americas have a total of 15 publications, with the United States leading with nine publications; 7.3% of the records are from Latin America. Like the United States, the remaining American countries are not under water stress, except for Mexico, which is reported to be in scarcity according to the Falkenmark indicator. Africa and Oceania recorded five and one publications, respectively, with Africa facing scarcity and absolute scarcity across its territory. The remaining 10 publications were excluded as they were global or cross-border studies. A significant trend highlights the relationship between scientific research focused on water management models and the issue of water scarcity, particularly in countries located in tropical and subtropical climatic regions. This correlation suggests that these areas, which are highly exposed to climatic variability and extreme events such as prolonged droughts and severe floods, have become a priority in water management research.

It is important to highlight that a country's economic development directly influences its scientific production. The promotion or limitation of this activity depends on the specific social, economic, and political context. A high GDP is often associated with greater investment in Research and Development (R&D), which supports a more robust scientific output. In Latin America, for example, a lack of focus on teacher training practices linked to research has shown a tendency to reduce scientific productivity [29].

This difference in resource allocation and educational approaches may explain why countries such as China, the United States, and several European nations have significantly higher scientific production compared to Latin America.

The increasing pressure on water resources in these regions is partly driven by rising demand due to multiple factors, including population growth, urban and agricultural expansion, and industrial development. These drivers have underscored the need to develop models capable of assessing and optimizing water allocation to ensure equitable access and long-term sustainability.

Furthermore, studies in these areas aim to identify innovative solutions that integrate technological, regulatory, and community-based approaches to enhance water resilience, mitigate the adverse effects of climate change, and guide development toward achieving water security.

The evolution of research on the technical and methodological approaches of water management models was analyzed to determine if the three approaches of integrated water management were addressed during the assessment, optimization, and simulation of the equitable distribution process of water resources among different uses. A review of articles published over 21 years (2003-2024) was conducted. The number of publications with an economic-social focus was 26, with this focus dominating during the first 12 years with a total of 9 publications (Figure 4).

After 2015, there is a marked dominance of the economic-social focus, with 23 out of 26 publications analyzed for this study period. This trend may be related to the fact that agriculture, industry, and municipal water provision are the primary stakeholders in blue water utilization, leaving the general population in the tertiary group [18]. Water market models, where a price is assigned to water, are commonly used in several countries worldwide, although results vary, complicating their application [30]. These types of models aim to improve water use efficiency by increasing its price, thereby encouraging users to prefer crops with higher economic value or that require less water [9].

While the economic-environmental link shows limited recurrence, the economic-social-environmental triplet in the last decade shows increased participation, reporting 14 out of 19 records (Figure 4).

Additionally, the concept of water footprint, both green and blue, is a common evaluation parameter across numerous studies. However, its definition shows uncertainty in evaluating water resource allocation models. This is because it refers to the volume withdrawn according to the source for consumption in a socio-economic activity, without concern for balancing the water requirements of the environmental system. Although there are records where a volume planned for the environment, known as environmental flow, is considered, it should represent 80% of the flow to avoid impacting ecosystem structure and function, leaving 20% for socio-economic activities [31, 32]. Additionally, Hatamkhani et al. [12] mention that water allocation models have used economic objectives, but environmental factors are often disregarded or only considered to a limited extent.

The following is a selection of studies that apply various terms, indices, and indicators to evaluate and plan water management in agriculture.

The analysis identified three main clusters derived from a dataset of 863 keywords, applying a minimum occurrence threshold of six times in distinct articles. As a result, a total of 38 relevant keywords were obtained. Figure 5 illustrates these three major groups, each represented by a different color. The size of each concept indicates its frequency of occurrence within the analysis. “Water management” occupies a central position within the network, strongly associated with analogous terms such as "water use" and "water supply," both linked to critical issues such as land-use change and climate change.

One of the main challenges identified in the literature is climate change adaptation, given that precipitation and temperature variability significantly impact water yield. These fluctuations affect water availability for agriculture, compelling farmers to adopt innovative practices to ensure productivity. However, in certain scenarios, the implementation of new strategies is insufficient to counteract negative effects, leading to increased production costs, higher food prices, and a decline in both quality and availability [33].

The second major issue identified is land-use change, which, driven by various factors, alters the conditions of natural vegetation, thereby affecting water availability. Multiple processes, such as reductions in evapotranspiration and infiltration, contribute to this phenomenon, with increased surface runoff being one of the primary causes. These findings highlight the importance of natural landscape conservation as a key strategy for water resource management. However, ongoing debate persists regarding the role of vegetation with high evapotranspiration in promoting regional precipitation and its subsequent effect on water production within specific watersheds [34].

These approaches encompass different perspectives on IWRM and are implemented through various models. These studies highlight the interactions among different water users, employing specific methodologies that enhance the understanding of their dynamics and needs (Table 2).

Another proposal for future studies after of this review, based on identified gaps, is to use different databases with a larger number of publications in Spanish to gain a better understanding of the situation in Latin America. The current research yielded very few articles from this region, indicating a possible underrepresentation of research conducted in these countries. This approach could enrich the analysis and provide a more comprehensive and contextualized view of water management in Latin America, a region facing significant challenges in this area.

This systematic literature review on water management models has provided a comprehensive overview of methodologies, revealing the approaches employed in different regions worldwide. The research identified that the watershed is the fundamental unit accepted for water resource management. Scientific development has focused on creating methodologies and tools for assessing water resources and their use in productive activities. However, a crucial question remains: How can IWRM models be effectively applied to address water security challenges and help mitigate water scarcity?

For this reason, it is essential to strengthen collaboration between academia, government, and the private sector. The synergy among these actors should be directed toward implementing clear and effective regulatory measures for water governance, promoting the development of strong policies, establishing monitoring and evaluation mechanisms, generating knowledge, and developing concrete solutions.

The analysis showed that more than 50% of the studies employed tool-based models, followed by water policies and specific practices. Scientific production varied significantly across continents, with Asia leading in the number of publications, although most of these countries face water scarcity according to the Falkenmark indicator. Europe and North America also contributed a substantial number of studies, although with varying degrees of water stress. However, the databases consulted contained relatively few publications from Latin America, highlighting comparisons with other regions worldwide. Consequently, this region was underrepresented, despite facing significant challenges in water management. Despite the significant challenges facing water management, Latin America remains underrepresented in scientific studies on the topic. The region faces multiple water-related problems, mainly linked to pollution, deforestation, and limited technological advances. Water pollution, driven by industrial and agricultural discharges and inadequate treatment of domestic wastewater, affects water quality and quantity, posing risks to both human populations and ecosystems. Furthermore, the loss of natural vegetation, particularly in watersheds, reduces water production by altering the hydrological cycle, decreasing infiltration rates, and increasing surface runoff, which favors erosion and sedimentation in water bodies.

These factors hinder sustainable water resources management, further highlighting the need for increased scientific production and policy-driven strategies tailored to the region’s specific challenges. Scientific production is linked to the availability of optimal conditions, such as funding for infrastructure and education focused on research. These factors, in turn, depend on a country's initiatives and economic conditions, such as its GDP.

A viable approach to strengthening research on water management in Latin America is fostering collaboration between local, national, and international academic institutions. Expanding these partnerships could facilitate access to global expertise and international funding sources, not only enhancing scientific research in the region but also promoting the exchange of knowledge and best practices. This would contribute to a broader understanding of local water-related challenges and support the development of solutions.

In terms of methodological approaches, a significant evolution toward an economic-social focus was observed, especially after 2015. This shift may be related to the increasing importance of industry, municipal water supply and agriculture, the primary stakeholders in blue water resources. However, the concept of water footprint, which represents the total volume of freshwater used to produce goods and services [23], introduces uncertainty in the evaluation of IWRM and supply models. This is because it primarily focuses on human consumption needs without adequately considering the water requirements of environmental systems.

In summary, this review underscores the need for more integrated and specific approaches to water management, addressing both socio-economic and environmental needs. The evolution of models and including studies in multiple languages and regions, can provide a stronger foundation for decision-making and implementing effective water resource management policies.