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Research Article
Navigating ecosystem service assessment tool selection for food-energy-water nexus: An interdisciplinary versus intradisciplinary perspective
expand article infoMei Hua Yuan‡, Te-Hsiu Huang§, Hoda Fakour|, Moslem Imani, I Chou‡
‡ Academia Sinica, Taipei, Taiwan
§ Agricultural Technology Research Institute, Hsinchu, Taiwan
| National Taiwan Normal University, Taipei, Taiwan
¶ National Cheng Kung University, Tainan, Taiwan
Corresponding author: Mei Hua Yuan (meihuayuan@gate.sinica.edu.tw)
Academic editor: Benjamin Burkhard
Received: 21 May 2025 | Accepted: 05 Sep 2025 | Published: 15 Sep 2025
© 2025 Mei Hua Yuan, Te-Hsiu Huang, Hoda Fakour, Moslem Imani, I Chou
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation: Yuan MH, Huang T-H, Fakour H, Imani M, Chou I (2025) Navigating ecosystem service assessment tool selection for food-energy-water nexus: An interdisciplinary versus intradisciplinary perspective. One Ecosystem 10: e159702. https://doi.org/10.3897/oneeco.10.e159702
 Open Access

Abstract

The interconnected nature of the food-energy-water (FEW) nexus underscores its significant impact on ecosystem services. Despite its importance, limited progress has been made in incorporating ecosystem service assessment tools into FEW nexus analysis and decision-making. This study examines how ecosystem service assessment tools incorporate interdisciplinarity and intradisciplinarity in the context of the FEW nexus, with the aim of informing future tool development and enhancing nexus governance. An integrated evaluation framework, based on interdisciplinary and intradisciplinary indicators, was developed. The framework was applied through expert elicitation to assess six ecosystem service assessment tools relevant to the FEW nexus. This study finds that, while ecosystem service assessment tools exhibit considerable variation in intradisciplinary performance, their interdisciplinary scores are consistently low and narrowly distributed. The study also finds that, while ecosystem service tools are widely applied across FEW systems, none provides a fully integrated nexus framework. Their strengths lie in connectivity and innovation within the assessment domain, whereas weak performance in empowerment under the accessibility domain. As a key contribution, this study introduces a decision tree to guide tool selection, based on FEW nexus needs. This study suggests that existing tools primarily support only basic integration of FEW systems and highlights the need for more comprehensive evaluation indicators.

Keywords

natural resource decision support, sustainability trade-offs, systems integration modelling, participatory environmental planning, ecosystem accounting frameworks, tool evaluation methodology, cross-sector governance

Introduction

Human activities and economic development largely depend on support from the food, energy and water systems (Sachs et al. 2019). Zero hunger, access to clean water and sanitation and affordable and clean energy are essential for human well-being. As the world population reaches 8 billion, the demand for food, energy and water is increasing (Albrecht et al. 2018). These three elements are not independent and the interactions amongst them are numerous and substantial (Simpson and Jewitt 2019). Due to the interdisciplinary nature of the relationships amongst these three elements, the FEW nexus approach has been developed to manage the linkages (Anandhi et al. 2023). This approach was first conceived by the 2011 nexus conference in Bonn to promote the inseparable links amongst the three elements. Recent research has increasingly emphasised the critical role of natural systems within the FEW nexus, highlighting that neglecting ecological functions can lead to unintended sustainability trade-offs (Lucca et al. 2025).

The FEW nexus offers a promising conceptual method to evaluate the interlinkages towards sustainable resources management (Zhuang et al. 2021, Xu and Yao 2022, Karamian et al. 2023). Past research documented that a secure supply of ecosystem services serves as the pillar that the FEW domains are often based on and address the consequences of changes to relevant ecosystem services (Qian and Liang 2021, Xu and Yao 2022). Ecosystem services are the direct or indirect benefits humans obtain from ecosystems (Costanza et al. 1997). These services can be classified into three categories, namely, provisioning, regulating and cultural services (Haines-Young and Potschin-Young 2018). Ecosystem services are at the centre of the nexus because they are involved in the food-energy-water system, making it important to understand their role in providing these benefits for human well-being (Yuan et al. 2022).

The assessment of ecosystem services within the FEW nexus has predominantly focused on regulating and provisioning services, each closely linked to one or more key resource domains. Food-related services are mainly represented through provisioning functions such as food production and livestock supply (Yuan and Lo 2020, Shi et al. 2022, Zhou et al. 2023). Water-related services are primarily associated with regulating functions, including water supply (Karabulut et al. 2016, Shi et al. 2022, Zhou et al. 2023), soil erosion and flood control (Yuan and Lo 2020) and sediment regulation (Yuan and Lo 2020, Zhou et al. 2023). In the energy domain, carbon sequestration is commonly highlighted due to its relevance for climate regulation and its indirect link to energy system sustainability (Yuan and Lo 2020, Zhou et al. 2023). Despite this growing body of work, cultural ecosystem services remain significantly underexplored (Yuan and Lo 2020, Zhou et al. 2023). This imbalance reveals a research gap and highlights the need for ecosystem service assessments that move beyond partial treatment of the FEW nexus.

Progress has been made in analysing the relationship between the FEW nexus and ecosystem services. ICIMOD (2012) estimated the contribution of Himalayan ecosystems to the security of food, energy and water systems in South Asia. Karabulut et al. (2016) assessed water provisioning services and the associated benefits using a hydrological model soil and water assessment tool (SWAT) to analyse the ecosystem–water–food–energy nexus. Arthur et al. (2019) demonstrated how increased intensity of food, energy and water activities weakened ecosystem services. Yuan and Lo (2020) considered multiple dimensions of ecosystem services in sustainability scenarios. Shi et al. (2022) assessed the temporal and spatial pattern of the land, water, food and habitat nexus under the impact of urbanisation and explored tradeoffs within the food-water-land ecosystem nexus. Zhou et al. (2023) linked the dynamics of multiple ecosystem services and its stressors in terms of food-energy-water interactions. The results indicate that ecosystem services should be considered as constraining variables in food-energy-water-related policy formulations.

A wide array of tools has been developed to support ecosystem service assessment-related functions, including mapping, valuation and scenario analysis in decision-making. These tools have been applied in practical contexts, such as conservation planning (Yuan et al. 2017, Aziz 2023), natural resource management (Cong et al. 2020) and land-use planning (Jafarzadeh et al. 2021). Although such tools facilitate the assessment, valuation and mapping of ecosystem services, their selection remains a key factor influencing their integration into policy development processes (Mengist et al. 2020). Recent literature has increasingly emphasised the need for structured guidance to support tool selection in applied decision-making contexts. Kaddoura and El Khatib (2017) stress the importance of aligning tool choice with the objectives of nexus modelling and integrated policy planning. Shannak et al. (2018) highlight the need to strengthen the link between conceptual models and operational decision-making. Dargin et al. (2019) identify a persistent disconnection between theoretical tool development and on-the-ground application. Taguta et al. (2022) note that overly complex tools often pose practical implementation challenges. These studies collectively suggest that advancing the usability of ecosystem service tools within the FEW nexus is both timely and necessary.

Several studies point out the need for appropriate ecosystem service assessment tools for specific targets. Cremades et al. (2019) emphasise the importance of incorporating ecosystem services assessment into forward-thinking approaches to navigate the nexus effectively. Recent literature points to two key dimensions for evaluating ES assessment tools: interdisciplinary capacity and intradisciplinary robustness. Interdisciplinary capacity refers to a tool’s ability to integrate ecological, social and economic domains to inform complex systems governance, such as that required by the FEW nexus (Bagstad et al. 2025). In contrast, intradisciplinary robustness focuses on how well a tool aligns with core ecological principles and established methods within the ecosystem service assessment field (Huang et al. 2024). As Carpenter et al. (2009) and Steffen (2009)have argued, managing today’s socio-ecological systems requires both cross-disciplinary integration and disciplinary depth. Yet, despite the growing number of tools and datasets, much of this knowledge remains siloed and underused (Cockburn 2021). Evaluating these two dimensions is thus fundamental to understanding how well current tools support integrated and discipline-grounded approaches to ecosystem service assessment within the FEW nexus context.

This research highlights the need for appropriate nexus tools that would enhance the integration of ecosystem service assessment and the FEW interlinkages under study. This study aims to evaluate and compare existing ecosystem service assessment tools, based on their interdisciplinary capacity and intradisciplinary robustness within the context of the FEW nexus. It addresses two key research questions. The first examines how these tools perform with respect to interdisciplinary integration and intradisciplinary coherence. The second explores how the functional gaps identified in these tools can be addressed to support future tool development and improve their practical application in FEW nexus governance. This paper begins by outlining the assessment approach in the Methodology section, drawing on both an integrated framework and insights from expert elicitation. The Results section investigates how the tools support integration across and within disciplines and how their functional gaps can be addressed to improve FEW nexus governance. The Discussion section highlights the main strengths and limitations of the evaluated tools in addressing the complexity of the FEW nexus. The Conclusions section distills key insights and recommendations to enhance tool effectiveness.

Methodology

This study employed a three-step methodology combining a systematic literature review, expert-based evaluation and synthesis. In the first step, a systematic review was conducted to identify six ecosystem service assessment tools relevant to the FEW nexus. A PRISMA-based summary of the selection process and a complete flow diagram along with the list of included studies are provided in Suppl. material 1. Drawing on insights from the literature and theoretical foundations of interdisciplinary and intradisciplinary perspectives, an integrated evaluation framework was developed. This framework includes two complementary matrices, each comprising a set of predefined indicators designed to assess tools from both perspectives. In the second step, expert elicitation was carried out with 14 researchers experienced in food, energy, water and ecosystem service assessment. Each expert independently scored the six tools using the evaluation matrices. In the third step, the results were visualised through scatterplots and boxplots to reveal relative performance. The evaluation findings were then synthesised into a practical tool selection guide. The workflow of this research is as shown in Fig. 1.

Figure 1.

The workflow of this research.

Ecosystem service assessment tools selection for this study

The methodology used to screen and select relevant literature for this study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. This research conducted a systematic literature review across three academic databases: ScienceDirect, Web of Science and Google Scholar. The review covered literature published between 2005 and 2023, using consistent Boolean search terms: "ecosystem services" AND "assessment tools" AND ("food" OR "energy" OR "water" OR "nexus"). Minor syntax adjustments were applied to accommodate database-specific formatting, but the search logic remained equivalent. The initial search yielded 138 records. After removing duplicates and screening titles and abstracts for relevance, 44 peer-reviewed articles and nine review papers were selected for full-text analysis. Inclusion criteria required that each study: (1) apply or evaluate an ecosystem service assessment tool in the context of at least one of FEW domain and (2) focus on tools that remained active and publicly accessible as of December 2023.

Table 1 presents references supporting the selection of each ecosystem service assessment tool. Identified through a PRISMA-guided review, these sources indicate the documented application and relevance of the tools to FEW nexus studies. Amongst these publications, a total of six tools were selected.

Table 1.
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Ecosystem service assessment tools selected for comparison, based on systematic review evidence.

Assessment tools

References

ARIES (Artificial Intelligence for Ecosystem Services)

Bagstad et al. (2012), Villa et al. (2012), Balbi et al. (2015), Barquín et al. (2015), Sharps et al. (2017), Kerebel et al. (2019), Martínez-López et al. (2019), Capriolo et al. (2020), Yuan and Lo (2020)

Co$tingNature

Adedeji and Elegbede (2018), Aziz and Van Cappellen (2019), Willcock et al. (2019), Mulligan et al. (2020), Chaplin-Kramer et al. (2022), Musetsho et al. (2022), Shi et al. (2022), Correa et al. (2023), Farahani and Asgharzadeh (2023)

InVEST (Integrated Valuation of Ecosystem Services and Trade-offs)

Leh et al. (2013), Beusen et al. (2015), Cabral et al. (2016), Ochoa and Urbina-Cardona (2017), Sharps et al. (2017), Trodahl et al. (2017), Adedeji and Elegbede (2018), Willcock et al. (2019), Shi et al. (2022)

Social Values for Ecosystem Services (SolVES)

Sherrouse et al. (2011), Sherrouse et al. (2014), Paudyal et al. (2018), Pan et al. (2022)

TESSA (Toolkit for Ecosystem Service Site-based Assessment)

Birch et al. (2014), Peh et al. (2016), Liu et al. (2017), Ávila-García et al. (2020), Calvo Robledo et al. (2020), MacDonald et al. (2020), Aung et al. (2021), Perosa et al. (2021), Ratto et al. (2022)

Value transfer

Troy and Wilson (2006), Plummer (2009), Kubiszewski et al. (2013), Frélichová et al. (2014), Yuan et al. (2017), Willcock et al. (2019), Zhou et al. (2020)

Review papers Farrell et al. (2011), Bagstad et al. (2013), Landuyt et al. (2013), Engel et al. (2017), Jiang (2017), Zhao et al. (2020), Delpy and Pedersen Zari (2021), Wang et al. (2021), Sanou et al. (2023)

Tool descriptions

ARIES (Artificial Intelligence for Ecosystem Services)

ARIES is a web-interface ecosystem services modelling platform. It can accommodate a range of analysis including scenarios, spatial assessment and economic valuation estimation, optimisation of payments for ecosystem services programmes and spatial policy planning.

Co$tingNature

Co$tingNature is a web-based tool for spatial and ecosystem services analysis. It assesses human interventions (i.e. land-cover and land-use change) impacts on the natural system and provides global or local scale relative indexes. Conservation prioritisation, co-benefits, pressures and threats can be analysed in terms of monetary valuation.

InVEST (Integrated Valuation of Ecosystem Services and Trade-offs)

InVEST is a set of software models for mapping, modelling and quantifying ecosystem services. InVEST requires available input data to assess biophysical or monetary value under different scenarios.

Social Values for Ecosystem Services (SolVES)

SolVES allows users to identify, assess and map social values. The cultural ecosystem services, such as aesthetic, historical, therapy and recreational values can be assessed combining spatial and points-based responses from surveys.

TESSA (Toolkit for Ecosystem Service Site-based Assessment)

TESSA is a manual providing guidance and rapid methods to estimate the benefits people obtain from nature at particular sites. TESSA generates primary data information by requiring stakeholder participation that can be used to influence decision-making.

Value transfer

The Value transfer method is an environmental-economics methodology which applies quantitative estimations of ecosystem service values from existing study sites to another policy site. Value transfer assumes a constant unit value per hectare when specific information, such as detailed model outputs, local economic valuations or stakeholder engagement processes, is not available.

Interdisciplinary and intradisciplinary evaluation matrix

The integrated evaluation framework comprises two complementary matrices. This study adopts the definitions of intradisciplinary and interdisciplinary research from Aboelela et al. (2006) and Schary and Cardinal (2015) and applies them to evaluate ecosystem service assessment tools in the context of the FEW nexus.

The intradisciplinary evaluation matrix is guided by a single criterion. This criterion is the alignment of each tool with the System of Environmental-Economic Accounting-Ecosystem Accounting (SEEA-EA), a framework developed by the United Nations to integrate ecosystem services into national accounting systems. SEEA EA is widely used for assessing sustainability (Hamilton 2015), guiding policy (Markandya et al. 2022) and identifying indicators for environmental and economic planning (Yermolenko et al. 2020). In this study, intradisciplinary performance is evaluated, based on five specific SEEA-EA account types. These are ecosystem extent accounts, ecosystem condition accounts, ecosystem services flow accounts in physical terms, ecosystem services flow accounts in monetary terms and monetary ecosystem asset accounts. Tools were scored according to the number of account types they address. The scoring matrix for this evaluation is shown in Table 2.

Table 2.
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Intradisciplinary evaluation matrix.

Criteria

Score

Scoring descriptions

Alignment with SEEA-EA

1

Tool applies to only one SEEA-EA account type.

2

Tool applies to two SEEA-EA account types.

3

Tool applies to three SEEA-EA account types.

4

Tool applies to four SEEA-EA account types.

5

Tool applies to all five SEEA-EA account types.

Note: The five SEEA EA account types include: ecosystem extent, ecosystem condition, physical flow of services, monetary flow of services and monetary ecosystem assets. Index values are scored on a unified five-point scale, where: 1 very low, 2 low, 3 moderate, 4 high and 5 very high.

The interdisciplinary evaluation matrix focuses on a tool’s ability to address the complexity of the FEW nexus. It is informed by governance principles proposed by Yuan and Lo (2022) and is structured around three criteria: assessment, awareness and accessibility. Under each criterion, nine indicators were identified: connectivity, innovation, equitability, participation, coordination, sharing, legitimacy, empowerment and strategy. Each of these nine indicators is scored on a scale from one to five. The full set of definitions and scoring descriptions for each indicator is presented in Table 3.

Table 3.
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Interdisciplinary evaluation matrix.

Criteria/ indicator

Score

Scoring descriptions

Assessment

Connectivity

1

Tool applies to only one of the three FEW domains.

2

Tool applies to two of the three FEW domains.

3

Tool applies to all three domains with basic integration.

4

Tool effectively integrates all three FEW domains.

5

Tool demonstrates seamless integration across all three FEW domains.

Innovation

1

Tool lacks openness, accessibility and technical quality.

2

Tool offers limited technical features and low usability.

3

Tool is functional with acceptable usability and partial accessibility.

4

Tool is well-designed, accessible and technically sound.

5

Tool is highly innovative, open, user-friendly and technically advanced.

Equitability

1

Tool disregards equity or fairness in outcomes.

2

Tool shows minimal concern for equitable considerations.

3

Tool includes some elements promoting equity.

4

Tool actively supports fair outcomes across sectors or groups.

5

Tool is designed to maximise equitable outcomes and reduce trade-offs.

Awareness

Participation

1

No stakeholder involvement is considered.

2

Minimal stakeholder input is included.

3

Stakeholder involvement is partial or limited.

4

Stakeholders are clearly involved throughout the process.

5

Tool strongly integrates diverse stakeholder perspectives and input.

Coordination

1

No attempt at cross-sector coordination.

2

Coordination is limited or informal.

3

Tool includes some effort to integrate sectors.

4

Tool enables coordinated actions across FEW sectors.

5

Coordination is a core feature, enabling full multi-sector integration.

Sharing

1

No data or outcome sharing mechanisms are present.

2

Basic sharing mechanisms are included, but limited in scope.

3

Tool facilitates some data or knowledge sharing.

4

Sharing is well-supported and encouraged.

5

Tool promotes open, transparent and comprehensive sharing practices.

Accessibility

Legitimacy

1

Tool lacks scientific credibility or procedural fairness.

2

Tool’s legitimacy is weak or poorly demonstrated.

3

Tool is generally accepted, but with some limitations.

4

Tool is trusted and methodologically sound.

5

Tool is widely recognised as fair, transparent and scientifically valid.

Empowerment

1

Tool does not support capacity building or adaptive governance.

2

Tool provides limited potential for learning or problem-solving.

3

Tool offers some empowerment and learning opportunities.

4

Tool facilitates adaptive learning and decision-making.

5

Tool enables continued empowerment and capacity building.

Strategy

1

Tool does not offer strategic guidance for governance.

2

Tool provides vague or minimal strategic direction.

3

Tool contains basic strategies, but lacks clarity or application.

4

Tool informs governance through clear strategies.

5

Tool delivers strategies for long-term governance.

Note: All criteria in the interdisciplinary index are scored on a unified five-point scale, where: 1 (very low): The tool shows minimal or no performance on the given criterion. 2 (low): The tool demonstrates weak or limited performance. 3 (moderate): The tool performs at an acceptable or average level. 4 (high): The tool demonstrates strong and effective performance. 5 (very high): The tool fully satisfies the criterion with outstanding performance.

The scoring process was informed by expert scoring involving fourteen researchers with experience in ecosystem service assessment or FEW-related tools. Each expert independently evaluated the six tools using the predefined evaluation matrices developed for this study. Experts were selected, based on their disciplinary background, familiarity with relevant tools, academic qualifications and professional recommendations. To ensure diversity, the panel included individuals from fields, such as environmental science, ecology, sociology, economics, hydrology and policy. Participants were based in different regions of the country, including the north, south, central and east and were selected with attention to variation in age and gender. Summaries of each tool were provided to participants in advance. Experts were contacted by email to obtain informed consent. A pilot phase was conducted with three experts to refine the scoring format and structure. Background information on the expert panel, including disciplinary field, region, age and gender, is presented in Table 4.

Table 4.
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Information on experts.

Expert

Field

Geographic area

Age

Gender

Expert 1

environmental science

northern region

70-

M

Expert 2

environmental science

northern region

50-70

F

Expert 3

environmental science

southern region

70-

M

Expert 4

environmental science

northern region

50-70

M

Expert 5

environmental science

northern region

30-50

M

Expert 6

environmental science

southern region

30-50

M

Expert 7

ecology

northern region

50-70

M

Expert 8

ecology

southern region

30-50

F

Expert 9

sociology

northern region

30-50

F

Expert 10

sociology

northern region

50-70

M

Expert 11

economics

northern region

70-

M

Expert 12

economics

central region

50-70

M

Expert 13

hydrology

central region

30-50

F

Expert 14

policy

eastern region

50-70

M

Each tool was evaluated using the predefined interdisciplinary and intradisciplinary criteria and the individual indicator scores were then aggregated to generate composite index values for both dimensions. These values served as the basis for visualisations using scatterplots and box plots. In the scatterplots, the intradisciplinary index value appears on the x-axis as the independent variable, while the interdisciplinary index value is plotted on the y-axis as the dependent variable. Each point represents a specific assessment tool, while the accompanying box plots illustrate the distribution of index values.

Results

Visualisation of tool interdisciplinarity and interdisciplinarity

In the visualisation of tool interdisciplinarity and intradisciplinarity, indexes are computed for each tool, based on the criteria presented in previous section. The results of the scoring processes are visualised into scatterplot displays in Fig. 2. We use the intradisciplinary index as the independent variable to examine its potential relationship with the tool’s interdisciplinary applicability, which is treated as the dependent variable. The figure is not intended to imply causality, but to visualise possible associations between the two indicator sets. The outcomes of the intradisciplinary index for the different tools are as follows: ARIES (4.5), SolVES (4), InVEST (3.5), Co$tingNature (2.5), TESSA (2) and Value transfer (1). The outcomes of the interdisciplinary index for the different tools are as follows: Co$tingNature (3.8), ARIES (3.5), InVEST (3.5), SolVES (2.9), Value transfer (2.8) and TESSA (2.4).

Figure 2.

Interdisciplinarity and intradisciplinarity visualisation of tools.

This study highlights two main findings. First, ecosystem service tools exhibit substantial variation in intradisciplinary performance, with scores ranging from 4.5 (ARIES) to 1 (value transfer), whereas their interdisciplinary scores are relatively concentrated, typically between 2.4 and 3.8. This discrepancy reflects fundamental differences in the evaluation criteria. Intradisciplinary assessment is based on clearly defined benchmarks, particularly the tool’s alignment with the SEEA-EA accounting framework. In contrast, interdisciplinary assessment relies on broader and less standardised criteria, which are still evolving. Tools often achieve similar scores despite differing levels of FEW integration, reflecting the early stage of methodological development in interdisciplinary ecosystem service assessment within the FEW nexus context. Second, none of the assessed tools achieved an interdisciplinary score above 4, with most ranging between 2.4 and 3.8. This pattern suggests that existing tools primarily support basic or preliminary integration of FEW systems. While some tools incorporate cross-sectoral interactions through scenario analysis or spatial modelling, they generally lack more comprehensive features, such as structured support for governance processes, mechanisms for stakeholder engagement or integration of institutional dimensions.

The interdisciplinary and intradisciplinary indices provide useful distinctions for aligning tool selection with user needs. Tools with higher interdisciplinary scores tend to be more relevant for government actors who need to address policy integration across FEW sectors. In contrast, tools with strong intradisciplinary performance are better suited for evaluators and analysts engaged in detailed ecological or sector-specific assessments. For stakeholders, especially community-based users, tools that balance accessibility with conceptual clarity are essential, regardless of index scores. Researchers may draw on both indices to identify tools that support either broad nexus integration or focused disciplinary analysis, depending on the scope of their inquiry.

Tool interdisciplinary index scores

Figs. 3 to 5 present the interdisciplinary index scores within the framework of assessment (connectivity, innovation, equitability), awareness (participation, coordination, sharing) and accessibility (legitimacy, empowerment, strategy). The overall scores are calculated by averaging the three sub-criteria within each domain and then taking the mean of the three domain scores. The domain scores are 3.27 for assessment, 3.43 for awareness and 2.77 for accessibility.

a. Tool interdisciplinarity for assessment

As shown in Fig. 3, the tool interdisciplinarity scores across the three assessment domains are as follows: connectivity (3.48), innovation (3.48) and equitability (2.79). These values indicate that equitability is the most challenging domain, receiving the lowest overall scores amongst the methods assessed. None of the methods achieves consistently high performance across all domains. ARIES and Co$tingNature exhibit relatively stable and high levels of performance, with minimal variation across domains. In contrast, InVEST, SolVES, TESSA and value transfer show greater variability, with performance differing substantially between domains. The selection of assessment tools should be aligned with the specific objectives and priorities of the evaluation. Methods demonstrating consistent and balanced performance (ARIES and Co$tingNature) may be positioned as central components within an assessment framework, while others may be incorporated to complement and address domain-specific limitations. For instance, InVEST may be used to enhance assessments related to connectivity.

Figure 3.

Interdisciplinary index for assessment domain. A higher index refers to a higher interdisciplinary tool.

b. Tool interdisciplinarity for awareness.

As shown in Fig. 4, the tool interdisciplinarity scores across the three awareness-related assessment domains are as follows: participation (2.7), coordination (2.79) and sharing (4.75). These values indicate that sharing is the strongest domain in terms of interdisciplinary integration, while participation and coordination show substantially lower scores. Tool-specific patterns are also evident. TESSA consistently performs at the upper end across all three domains, particularly excelling in participation and sharing. Co$tingNature and ARIES show moderate performance overall. InVEST, SolVES and value transfer perform poorly in participation and coordination, with stronger results mainly in the sharing domain. An important observation is the tight clustering of scores in the sharing domain, suggesting a higher level of methodological consensus or robustness in that area. In contrast, the broader spread and presence of low outliers in participation and coordination indicate potential gaps in tool design or limited attention to these dimensions in existing assessment frameworks.

Figure 4.

Interdisciplinary index for the awareness domain. A higher index refers to a higher interdisciplinary tool.

c. Tool interdisciplinarity for accessibility

Fig. 5 shows the interdisciplinary index scores across the three dimensions of the accessibility domain: legitimacy, empowerment and strategy, with median scores of approximately 3.55, 1.9 and 2.8, respectively. InVEST performs consistently well across all dimensions, reflecting a more integrated and participatory approach to accessibility. Other tools show more variable or limited results. Value transfer and SolVES consistently perform poorly across all three dimensions, suggesting limited attention to legitimacy, empowerment and strategy. Notably, empowerment appears to be the weakest dimension overall, with most tools scoring low and clustering between 1 and 3 on the index. This suggests a general lack of methodological depth and differentiation in supporting empowerment-related objectives.

Figure 5.

Interdisciplinary index for accessibility domain. A higher index refers to a higher interdisciplinary tool.

Decision tree for ES tool selection

One single consideration may not be useful because many of the tools can be applied in many contexts. To synthesise considerations and which tools can be used in each case in combination, this research developed a set of decision trees that can help a practitioner to select a tool, based on practical considerations. We used several standard sets of criteria that we believe are needed when selecting existing tools for measuring FEW nexus and modelling ecosystem services for study sites, including: applicability to FEW domains, level of stakeholder engagement required, outputs expressed as maps, capacity for data collection, synergies and conflicts analysis. Fig. 6 illustrates the decision tree for ES tool selection, based on practical considerations, building on existing comparisons of ecosystem service tools.

Figure 6.

Decision tree for ES tool selection, based on practical considerations. It synthesises multiple criteria, including applicability to FEW domains, stakeholder engagement level, map outputs, data collection capacity and synergies and conflicts analysis.

When users seek a comprehensive analysis to understand the intricacies of the FEW nexus, InVEST emerges as the preferred tool. Additionally, the selection of tools varies when considering stakeholder involvement. For instance, SolVES and TESSA excel in showcasing stakeholder-engaged analysis results, particularly with SolVES offering cartography. In scenarios devoid of stakeholder participation, ARIES can furnish decision-making maps. Moreover, Co$ting Nature can be further employed for nuanced analyses of trade-offs and synergies.

a. Generalisable modelling for assessment: ARIES, Co$tingNature, InVEST, SolVES, TESSA, Value transfer

The majority of ecosystem service assessment tools seek to quantify services for food, energy and water perspectives, respectively. Depending on the context, users might be interested in assessing provisioning services, such as fisheries, aquaculture, wild goods, livestock grazing and energy generation; regulating services, such as freshwater supply, water purification, flood protection; and cultural services, such as aesthetic, educational, recreational and therapeutic services. Not all tools are suitable to assess all services, so it is useful to consider which ecosystem services are relevant to food-energy-water domains before selecting a tool.

These tools differ in their applications. The current ARIES release includes five food-energy-water relevant ecosystem services – riverine and coastal flood regulation, freshwater supply, pollination, subsistence fisheries and cultural services. Co$ting Nature is designed for seven food-energy-water relevant services – grazing/fodder (livestock grazing), non-wood forest products (harvested wild goods/hunting), water provisioning (quantity, quality), fish catch, natural hazard mitigation (flood) and recreational value. The current InVEST model includes ten food-energy-water relevant services - crop pollination, crop production, offshore wind energy, reservoir hydropower production (water yield), seasonal water yield, urban flood risk mitigation, urban stormwater retention, water purification, wave energy and cultural services. SolVES tool intends to quantify and map the perceived social values for ecosystem services using preference surveys. This typology largely corresponds to cultural services, such as aesthetic, recreation, spiritual, education and cultural heritage. No food-energy-water relevant typology under provisioning services or regulating services was observed. TESSA is designed to use surveys in settings with stakeholders and decision-makers for eight services. Value transfer links ecosystem assessment data and make these accessible to the local assessments, which can include all food-energy-water relevant services. While it has the capability to capture more comprehensive food-energy-water domains, the scores are not high as experts concerned about the accuracy of the value transfer method.

b. Generalisable modelling for awareness: SolVES and TESSA

Ecosystem services assessment to support decision-making is greatly enhanced with early engagement of the actual stakeholders involved in the decisions. Two of the six models - SolVES and TESSA - were designed to capture information about social and cultural ecosystem services through stakeholder surveys or workshops. Currently, these two tools require conducting stakeholder surveys and running models to produce spatial outputs. Further, TESSA is distinctly place-specific, accounting for locally human preferences underlying ecosystem services. It explores how development policies in terms of future scenario affect ecosystem service patterns. Scenarios can help communicate the outcomes of different choices for governance while, at the same time, enhancing stakeholders in a powerful learning process by assessing the impact of decisions and exploring possible futures.

c. Generalisable modelling for accessibility: ARIES, Co$tingNature, InVEST

Co$tingNature and InVEST tools produce maps to display results in biophysical units and per-unit monetary values. Co$tingNature and InVEST provide functions of identifying the beneficiaries of these services and assessing the impacts of human interventions. In addition, the ARIES model can be used to model physical budgets (the balance between supply and delivery) and physical flows (the link between the areas of supply and those of delivery) between supply and demand. These three reviewed tools can be used to estimate economic values and provide results that are spatial. The capacity of economic and spatial analysis helps decision-makers better understand the application of assessment outcomes.

Discussion

Interdisciplinary and intradisciplinary performance

This study bolsters the arguments previously put forth by researchers (Neugarten et al. 2018, Wang et al. 2021, Ghodsvali et al. 2022), highlighting that these tools, by facilitating comprehensive assessments, enhancing awareness and promoting accessibility, significantly contribute to fostering resilience and environmental stewardship. The results of this study reveal that current ecosystem service assessment tools display significant variation in both interdisciplinary integration and disciplinary robustness within the FEW nexus context. Tools such as ARIES and InVEST demonstrate relatively high interdisciplinary capacity. ARIES stands out by using semantic AI modelling to combine ecological, economic and spatial data, allowing it to simulate environmental flows and cross-sector trade-offs dynamically (Capriolo et al. 2020). InVEST, while rooted in biophysical modelling, supports interdisciplinary usage through its modular design and decision-relevant outputs, particularly in land-use and hydrological planning (Rahimi et al. 2020, Daneshi et al. 2021). Our expert elicitation confirmed that these tools are perceived as more adaptable to integrated FEW assessments.

Value transfer approaches, while not a conventional modelling tool, offer a streamlined way to apply economic valuation in FEW-related contexts. Although their intradisciplinary grounding in environmental economics is solid, their interdisciplinary flexibility is limited by assumptions that may not fully reflect local socio-ecological conditions (Brander et al. 2024). Experts noted that value transfer methods are frequently used due to their low data demands, but often lack nuance and spatial accuracy. Co$tingNature is grounded in ecological risk modelling and offers robust functionality for rapid global assessments of ecosystem services and stressors. However, its capacity to integrate economic and social dimensions remains underdeveloped and its interface is less amenable to stakeholder engagement (Willcock et al. 2020). Unlike ARIES or InVEST, it lacks the flexibility to model alternative futures or detailed local interventions (Willcock et al. 2023).

SolVES and TESSA demonstrate strong contributions in engaging with local communities and addressing cultural ecosystem services, an area traditionally overlooked in nexus assessments. SolVES, in particular, enables the spatial visualisation of non-material values, such as recreational or spiritual significance, which is crucial in contexts where cultural services influence resource decisions (Zhou et al. 2020). TESSA provides a site-based, participatory framework for ecosystem assessment, although it is limited in its ability to support dynamic or cross-sector modelling (Márquez et al. 2023) .

Compared to earlier literature, such as Grêt-Regamey et al. (2017) and Neugarten et al. (2018), this study contributes a more practice-orientated perspective by combining literature-based evaluation with empirical insights from expert users. Our findings underscore the divergence between theoretical potential and applied usability in complex FEW scenarios.

Tool functionality gaps and areas for improvement

This study identified several cross-cutting limitations across the six tools examined. Most tools provide limited support for assessing cultural ecosystem services, which are increasingly recognised as integral to resource governance (Huynh et al. 2022). SolVES is the notable exception, yet even it faces challenges in scaling and integrating with biophysical models (Chen et al. 2025). TESSA also captures qualitative and site-specific cultural values, but lacks interoperability with quantitative planning tools. Stakeholder participation is often superficial or post hoc (Iversen et al. 2024). While SolVES and TESSA explicitly aim to incorporate local perspectives, they are rarely integrated with broader system modelling or policy instruments. The gap between participatory engagement and technical robustness remains pronounced (Humaedi et al. 2025). Tools like Co$tingNature and value transfer methods are efficient, but largely expert-driven, offering little room for end-user input (Brander et al. 2024, Schlemm et al. 2025).

Only a few tools offer dynamic decision-support mechanisms. ARIES and InVEST allow for scenario modelling and provide spatially explicit outputs suitable for providing information for trade-offs. However, even these tools have limited capacity for real-time feedback or uncertainty modelling. The absence of such features constrains their relevance for adaptive governance, especially in the context of climate volatility (Brandon et al. 2021). Tool accessibility remains a substantial barrier. High data and software requirements, steep learning curves and lack of multilingual interfaces limit usability, especially in developing contexts. Value transfer is more accessible, but sacrifices ecological realism and local relevance for ease of use (Brander et al. 2024).

These gaps are consistent with, but expand upon limitations, reported in previous reviews, such as Hülsmann et al. (2019) and Bagstad et al. (2025). By combining expert elicitation with systematic tool comparison, this study deepens our understanding of why certain tools succeed or fail in FEW nexus planning.

Implications for Future Tool Development

Findings from this study offer several key recommendations for advancing ecosystem service tools to better address the FEW nexus. Tools must move beyond single-discipline optimisation and develop true modular architectures (Hernández‐Blanco et al. 2022). This would enable users to plug in models or datasets relevant to specific local or national contexts (Bai et al. 2024). The flexibility observed in ARIES and InVEST should serve as a design benchmark.

Stakeholder engagement must be embedded from the outset. Future tools should facilitate co-design processes and allow for locally meaningful indicators and inputs (Vári et al. 2021). While SolVES and TESSA provide partial models, new tools should support multi-level governance integration and link grassroots concerns to national or regional policy scenarios.

Scenario modelling must become more interactive and uncertainty-aware (Pereira et al. 2024). Tools should allow users to explore trade-offs dynamically and integrate real-time data and feedback loops. Current limitations in this area hinder the ability of planners to respond to evolving environmental or social stressors (Vidal-Abarca Gutiérrez et al. 2022).

Future development should prioritise inclusive design (Meraj et al. 2021). Open-source code, customisable language settings and tiered user interfaces can bridge technical divides and broaden the reach of ecosystem service tools. Especially in low-capacity regions, minimising technical complexity, while preserving analytical rigour, is essential (Srivathsa et al. 2023).

Value transfer techniques should be expanded and improved because their speed and accessibility make them useful for preliminary assessments or rapid policy appraisals (Brander et al. 2024). Enhanced contextual calibration, clearer documentation of assumptions and integration with spatial models could significantly increase their value in nexus planning (Grammatikopoulou et al. 2023).

Limitation

This study relies on one-on-one expert elicitation with 14 experienced researchers. While the experts provided valuable qualitative insights, the relatively small sample size may limit the generalisability of the findings to broader sectors or contexts. In addition, the perspectives captured may not fully reflect the diversity of decision-making processes in the field and the potential for respondent bias remains a methodological limitation.

Conclusions

This study examined ecosystem service assessment tools in the context of the FEW nexus by developing an evaluation framework with indicators and applying it through expert elicitation. Six ecosystem service assessment tools were evaluated using interdisciplinary and intradisciplinary criteria to assess their relevance and applicability to FEW nexus-related challenges. The findings show that, although many tools have been developed to assess food, energy and water systems, none offers a fully comprehensive framework for integrated nexus assessment. Gaps remain in capturing interlinkages, supporting stakeholder engagement and enabling policy-relevant outcomes. These insights provide guidance for selecting appropriate tools for real-world applications and underscore the need for further development towards more integrated, decision-orientated frameworks. Future research should focus on building tools that better estimate cross-sector interactions, incorporate participatory processes and support effective governance for sustainable resource management.

Acknowledgements

This study was financially supported by the National Science and Technology Council of the Republic of China (113-2221-E-001 -004 -).

Funding program

Ministry of Science and Technology (113-2221-E-001 -004 -)

Conflicts of interest

The authors have declared that no competing interests exist.

References

Supplementary material

Suppl. material 1: Systematic review process  
Authors:  Mei Hua Yuan, Te-Hsiu Huang, Hoda Fakour, Moslem Imani, I Chou
Data type:  docx
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