Coevolution of coupled human-water systems (CHWS) is critical for long-term sustainable water management, linking to Panta Rhei. However, the study of CHWS suffers from complexity brought by diverse natural and social science disciplines. In this study, we investigated the general landscape of the theoretical frameworks, methods and data in CHWS case studies. Our meta-analysis, encompassing 205 cases, draws on eight proposed theoretical frameworks in four typologies, quantifying the prevalence and geographical distribution of methods and data. Results demonstrated the analytical strength of sociohydrology for CHWS, underscoring the need to integrate multidisciplinary theoretical frameworks. A combination of qualitative and quantitative methods and data would help overcome the limitations of each method when used in isolation, broadening the research scope of disciplines. This requires sociohydrology to enhance its ability to integrate diverse research approaches. The uneven global distribution of CHWS research teams highlights the necessity of increasing collaboration and resource sharing across borders.

Water management interventions are designed to mitigate undesirable aspects of coupled human-water systems (CHWS). However, due to the nonlinear feedback mechanisms inherent in CHWS, these interventions sometimes lead to unintended consequences that exacerbate the very issues they aim to resolve. To develop a generalized understanding of the underlying mechanisms behind such unintended outcomes, this study conducts a meta-analysis of 37 case studies from around the world. We identified six core subsystems and defined a critical pathway showing how hydrological perturbations propagate in a CHWS and lead to unintended consequences of interventions. By analysing case storylines, we identified the critical pathways and harmonize them into prevalent critical pathways, which most frequently lead to unintended consequences for specific phenomena, together with the key variables. The results of this study can support more sustainable and resilient water management, as it is the critical pathways that must be altered to avoid unintended consequences.

Abstract. Sociohydrology has advanced explanations of coupled human-water systems, but its translation into decision support remains uneven. We argue that a practical bridge from systems thinking to systems doing can be built around two complementary abstractions: (i) canonical feedback structures that make cases comparable without erasing context, and (ii) critical pathways that trace how interventions propagate through behavior, exposure, and outcomes. Canonical forms help organize recurring emergent phenomena such as the levee effect and reservoir effect, while critical pathways turn these insights into a repeatable workflow for intervention design, monitoring, and adaptive learning. We propose a minimal "systems doing loop" that links feedback mapping, pathway tracing, indicator selection, and iteration, with equity and legitimacy treated as explicit constraints on what counts as useful knowledge and acceptable action. This framing complements integrated water resources management by making unintended consequences operational and by clarifying what to monitor and revisit when system behavior changes.

Over 310 transboundary river basins span across 153 countries, covering 47.1% of the Earth's surface, including 52% of the world’s population, and accounting for almost 60% of the world’s freshwater flow. These river systems flow across political boundaries, creating a complex web of environmental, political, economic and security-related interdependencies. As riparian countries have their respective values, priorities and interests towards shared waters, managing transboundary water resources is a long-term and often challenging process. With the increasing hydrological variability due to climate change, accelerated population growth/urbanization, geopolitical instability, economic development, and global epidemics, the uncertainty in transboundary river water management has further intensified. Existing research offers a broad range of empirical studies based on detailed water event data but has not yielded universally applicable conclusions that can be generalized across all transboundary river basins. News media articles provide a full process understanding of the development of water events, recognized as a valid proxy to track societal values or public opinion on water issues, as well as reflect nuanced insights. This study, based on the constructed global transboundary river water conflict and cooperation news media articles dataset covering 105 out of over 310 transboundary rivers worldwide, with a time span from 1977 to 2022, employs text analysis methods to explore and identify patterns of transboundary river water conflict and cooperation dynamics. The findings will contribute to a deeper understanding of the dynamics on global transboundary river conflict and cooperation and provide insights for promoting water cooperation.

Value, technology, and policy are three interactive societal factors affecting the willingness, capacity, and formal rules of human interactions with water. Existing human-water models generally neglect the dynamic and accumulated processes of these factors, failing to explain the societal causes of changes in water practices. Here we developed nine process-based quantitative datasets of Value-Technology-Policy regarding water. They contain 17,003 newspaper articles and 801 public submissions to reflect different water values, 1337 ancient technologies and 40,303 patents for water technologies, and 720 water policy documents at various spatial (national, regional, state, and river basin) and temporal (decades to hundreds of years) scales. A consistent, 4-step content analysis approach was adopted to identify, collect and manually code five key elements (processes) of value, technology and policy: the time (“when”), location (“where”), actor (“who”), theme (“what”), and perspective/tone (“what effects”). Inter-coder reliability tests were conducted to ensure the consistency and validity of the data. These datasets will contribute to more process-oriented understanding of societal factors for improved human-water system modelling in the Anthropocene.

Media coverage of water events in transboundary river basins reflects the views of both riparian countries and beyond, and the conflict and cooperation dynamics could be biased due to the linguistic diversity. The aim of this study is to investigate whether any deviation exists in the depiction of water conflict and cooperation dynamics as reflected in the sentiments of French and English news articles, taking the Lancang–Mekong River basin and the Nile River basin as case studies. The results showed that news articles in English itself can reflect the trends of the cooperative or conflictive sentiments of the water events occurring within the basin, but French news is complementary in examining the attitudes and values of a few countries towards the shared river. The study would serve as an important reference for the perspective analysis of all riparian countries, as well as a basis for comprehending water conflict/cooperation dynamics in multiple languages.

Sentiment analysis of news media articles is essential for understanding the dynamics of conflict and cooperation in transboundary rivers. However, it is not known which machine learning model(s) can best meet the requirement of sentiment analysis for transboundary rivers. This study presents a comparative examination of ten machine learning models commonly used in the field of text sentiment analysis, including K-Nearest Neighbors, Naive Bayes, Support Vector Machine, Decision Tree, Random Forest, Gradient Boosting Decision Tree, Extreme Gradient Boosting, Multilayer Perceptron, Long Short-Term Memory and Bidirectional Encoder Representations from Transformers, for five-class sentiment classification of 9382 news articles (1977–2022) attending to transboundary water conflict and cooperation. By evaluating their performance in terms of accuracy, precision, recall and F1-score, the Bidirectional Encoder Representations from Transformers (BERT) model demonstrated good overall performance and prediction capabilities for news articles with conflictive sentiments. By comparing with the AFINN sentiment dictionary, BERT showed superior performance in the prediction and identification of conflictive sentiment labels. And by validating against historical water events in the three river basins, BERT performed best in the Indus River basin. The findings of this study hold significant implications for government agencies in transboundary rivers, allowing them to promptly assess and respond to public sentiment, thereby preventing water conflict and promoting water cooperation.

The transition of a country or a whole society to sustainability is a long-term goal that involves a society’s willingness to carry out such a change and the governance structure to support it. Understanding the role of the governance structure in enabling or constraining the change dynamics of societal values can more effectively foster desired transitions. This paper aims to reveal the co-evolutionary dynamics in the transition processes of the societal value of water resources and the network configurations of water governance in Australia and China in different socioecological contexts. Newspapers were used to track societal value and structural change in water governance. One mainstream newspaper was selected from each country, spanning a timeframe of 175 years in Australia and 72 years in China. The key finding is that the transition in societal value in both countries followed a similar sigmoid function. The value transition process in both countries benefited from a centralized governance structure, particularly in the take-off stage of the transition.

There has been increasing recognition that the global water crisis is due to lack of understanding of wider economic and socio-cultural perspectives, resulted from the intended and/or unintended consequences of co-evolution of coupled human-water systems. In light of such recognition, Panta Rhei Initiative (2013-2022) was proposed to focus on changes in both hydrology and society. Approaching end of this decade, it is time to synthesize the knowledge gained in our understanding of coevolution and prediction of coupled human-water systems. The synthesis will produce a book which includes five parts: (I) Motivation and Overview, (II) Theoretical Foundations and Methodological Approaches, (III) Synthesis of Work Done and Understanding Gained in Specific Application Areas, (IV) Panta Rhei Case Studies, (V) Grand Synthesis and Recommendations. This abstract will present a brief introduction of current progress of Panta Rhei Book.

Abstract. Increasing hydrologic variability, accelerating population growth, and resurgence of water resources development projects have all indicated increasing tensions among the riparian countries of transboundary rivers. This article aims to review the existing knowledge on conflict and cooperation in transboundary rivers from a multidisciplinary perspective and propose a socio-hydrological framework that integrates the slow and less visible societal processes with existing hydrological-economic models, revealing the hidden feedbacks between changes in societal processes and hydrological changes. This framework contributes to understanding the mechanism that drives conflict and cooperation in transboundary river management.

Abstract. Management of transboundary rivers will be one of the great political and environmental challenges of the 21st century if knowledge of conflict and cooperation is not fully developed. Transboundary river conflict and cooperation are critical for the sustainable development of river basins, regional security, and stability, and have significant scientific and practical implications. The construction of a dataset of transboundary water events – individual conflictive or cooperative interaction between riparian –provides important data support and factual basis for the study of transboundary rivers. However, the most representative research, the Transboundary Freshwater Dispute Database, is built by means of manual reading for information extraction, thus difficult for fast updating, also does not cover the global changes in the past decade. This research aims to build a methodological framework for news media datasets tracking of conflict and cooperation dynamics on transboundary rivers, provide mass of relevant data for the research of transboundary rivers in the globe, prepare a potent research toolkit, lay a solid foundation for further data mining research, and better suit the big data age. In order to test the effectiveness of the methodological framework and toolkit for dataset construction, this research analyses the word frequency and themes of the articles in datasets. The results show that the datasets built by this framework can reflect comprehensive themes of transboundary water conflict and cooperation. Through the analysis of media activity in different river basins, it is possible to get a global overview of the participation of countries located within and outside of the basin in transboundary water issues.

Transboundary rivers flow across political boundaries, requiring riparian countries to share a complex network of environmental, economic, political, social and security interdependencies. Transboundary river fluctuates in both space and time, and have multiple and conflicting demands on its uses, which have often resulted in tensions between riparian countries. Conflict and cooperation is thus an emergent phenomena of this co-evolved human-water systems. The choice of cooperative or conflictive behaviours from riparian countries is not only related to the nature of the water issue itself, but it attains more to the political, cultural, institutional, and socioeconomic conditions of the upstream and downstream countries involved. Understanding of the feedback mechanism is thus needed to be able to develop the understanding of how different actors cake to cooperation of conflict and knowledge to manage it effectively. As part of Panta Rhei Synthesis book, this study provides case study of transboundary human-water system by reviewing knowledge of conflict and cooperation dynamic from various disciplines, existing models and frameworks developed.

Riparian countries have their respective values and priorities for water management, and their values of shared water have fundamental impacts for their propensity to be involved in cooperative management and adhere to treaties/agreements. However, there is limited understanding of the changing values and interests of each riparian country. Taking the Lancang–Mekong River basin as a case study, this paper aims to analyse the evolution of water conflict and cooperation dynamics from the perspectives of multiple countries. Newspaper articles were used as the key data source as they provide insights into events reported on by the media that are representative of each country/sector they are published within. The results depict a trend of cooperative sentiments towards water events occurring within the region. The six riparian countries (China, Myanmar, Laos, Thailand, Cambodia, and Vietnam) had a greater average sentiment score (0.5) for cooperation than international countries (0.16) for the majority of the study period. The trend also shows that countries further downstream showed lower cooperative sentiments, except for Vietnam (China 0.86, Myanmar 0.58, Laos 0.46, Thailand 0.34, Cambodia 0.13, Vietnam 0.91). Dam infrastructure was often negatively reported (60 % of negatively reported articles), which is therefore a major contributor to conflict for the Lancang–Mekong River basin. Events that are positively reported are those that aid in connecting leaders and project developers between riparian countries including meetings, bilateral and multilateral cooperation, and development projects. These findings provide the basis for further revealing the mechanism of cooperation and conflicts as well as more proactively managing cooperation and conflict in the Lancang–Mekong River basin and beyond.

The Lancang-Mekong River (LMR) basin has historically been affected by severe floods and is likely to suffer further flood events with higher peaks and longer duration in the future due to climate change, which calls for collective action to respond. This study examined the potential flood control effect of coordinated operation of the LMR transboundary multi-reservoir system by establishing a distributed hydrological model coupled with a reservoir operating model, simulating the runoff of 13 tributaries and 5 mainstream sections. Results show that:① Flood magnitude at the five sections along the Mekong River is significantly reduced by mitigating flood recurrence from 200 years to 20-50 years.② In terms of flood control, the left-bank tributaries contribute more than the right bank. Tributaries with relatively higher flood control capacity are:Lancang, Nam Ou, Nam Ngum and Nam Theun, Nam Mun, Se Kong and Se San. ③ Different tributaries play a major role in flood control across regions. Luang Prabang's main flood control tributaries are Lancang and Nam Ou. At Nakhon Phanom, Lancang's flood control contribution is same as Nam Ngum and Nam Theun's sum. In the downstream of Pakse, the flood control contribution of Nam Mun and Se Kong are higher than Lancang. This research provides a reference for transboundary flood control cooperation between riparian countries, which face an important opportunity underpinned by the Lancang-Mekong Cooperation Mechanism (LMC).

The transboundary Lancang–Mekong River basin has experienced dynamics of cooperation over the past several decades, which is a common emergent response in transboundary coupled human–water systems. Downstream countries rely on the Mekong River for fisheries, agriculture, navigation and ecological services, while upstream countries have been constructing dams to generate hydropower. The dam construction and operation in upstream countries have changed the seasonality of streamflow in downstream countries, affecting their economic benefits. More recently, cooperation between upstream and downstream countries has been enhanced throughout the river basin. In this study, we introduce a quantitative socio-hydrological model to simulate hydrological processes, reservoir operations, economic benefits, policy feedbacks and therefore dynamics of cooperation within the Lancang–Mekong River basin. The model reproduces the observed dynamics of cooperation in the basin revealed by sentiment analysis of news articles. Hydrological variability such as droughts and human activities associated with reservoir operations affect dynamics of cooperation between the riparian countries, with importance attached to indirect political benefits of upstream playing an important role in the enhancement of cooperation. In this way, our study generated understanding of emergent cooperation dynamics in this transboundary river basin, and the socio-hydrological model used here provides a useful new framework to investigate and improve transboundary water management elsewhere.

Abstract. Riparian countries have their respective values and priorities for water management, and their values of shared water often has possible impacts for their propensity to involve in cooperative management and adhere to treaties/agreements. Improving transboundary water management therefore firstly requires nuance understanding of the changing values and interests of each riparian country to better understand factors that encourage and discourage changes toward cooperation or conflict. This paper provides understanding of the evolution of conflict and cooperation dynamics in Lancang-Mekong River Basin with in-depth analysis of the perspectives of multiple countries. Newspaper articles were used as a key data source as it provides insights into events reported on by the media that are representative of each country/sector they are published within. The results depict a continual trend of cooperative sentiments towards water events occurring within the region. The six riparian states have had a greater average sentiment score for cooperation than international countries for the majority of the study period showing that the region perceived transboundary water management more positively than global audiences. Except for few outliers, the trend also shows that countries further downstream showed lower cooperative sentiments. Dam infrastructure was often negatively reported, thus, it is likely a major contributor to conflict for the Lancang-Mekong River Basin, while events that are positively reported are those that aid in connecting leaders and project developers between riparian countries including meetings, bilateral and multilateral cooperation and development projects. These findings provide the basis for further revealing the mechanism of cooperation and conflicts through understanding these inherent and diverse perspectives of each riparian country, we can gain an insight into the underlying interests that create conflictive or cooperative environments and ultimately predict and manage cooperation/conflict in transboundary rivers.

The Columbia River Treaty, signed in 1961, solidifies cooperation between the United States and Canada to manage the operation of the Columbia River’s extensive dam network jointly to optimize benefits for the whole system. Under the treaty, Canada operates dams to provide flood protection and maximize hydropower potential downstream. In exchange, the U.S. compensates Canada with half of the estimated benefits of the treaty, which provides an economic incentive to cooperate not seen in many other transboundary basins. However, since the treaty was established, this highly-managed system has responded to unanticipated external social and environmental factors. For example, mounting social pressure in the 1990s to protect the aquatic environment resulted in operational changes to U.S. dams to accommodate flows for fish migration, which ultimately resulted in financial losses for hydropower producers. These changes affected the relative benefits each country receives from cooperation. Utilizing a range of hydrological, economic, social, and environmental datasets, a socio-hydrological model was developed that simulates system operations using historical data to mimic operational changes, shifts in flood control and hydropower production, and cooperation dynamics. Renegotiations of the Columbia River Treaty started in 2018, and the new treaty in 2024 must include provisions for environmental protection that were, originally, not considered. The purpose of this study is to use the established model to envision how changing conditions such as climate change, spring fish flows, and First Nation rights would affect each country’s willingness to cooperate. For example, how would changes in snowpack upstream or seasonal changes in precipitation alter the hydrology of the basin and, in turn, the benefits each country receives from cooperation. This scenario analysis provides insight into how a revised treaty that takes future uncertainties into account would affect the balance of benefits to maintain or disrupt cooperation on the Columbia River.

Millions of people around the world are affected by water crises manifesting at different scales, such as increasing drought severity and flood risk, groundwater depletion, ecological degradation, poor sanitation, water pollution and its impact on human health. This global water crisis is increasingly interconnected and growing in complexity. Negative effects often result from a lack of understanding of wider economic and socio-cultural perspectives. More specifically, water crises can be deemed the intended or unintended consequences of long-term changes of social norms and values (or, more broadly, culture), ideology or political systems, which are not typically anticipated or accounted for in coping with water-related issues. Sociohydrology engages with these principles by examining the outcomes of water management and governance processes –successes and failures as well as the distribution of costs and benefits across social groups— themselves as subjects of scientific study. In this presentation, we show how feedback mechanisms between human and water systems can generate a wide range of phenomena (including crises) in different places around the world. Moreover, we argue that a generalized understanding of sociohydrological phenomena has an important role to play in informing policy processes while assisting communities, governments, civil society organizations and private actors to address the global water crisis and meet the Sustainable Development Goals, the societal grand challenge of our time.

The transboundary Lancang-Mekong River Basin has experienced both cooperation and conflict over the past several decades. Downstream countries (Thailand, Cambodia and Vietnam) rely on Mekong River for fisheries and agriculture, while upstream countries including China and Laos have been constructing dams to generate hydropower. The construction and operation of dams in upstream countries has changed the seasonality of streamflow in downstream countries, affecting their agriculture and fishery benefits. More recently, cooperation between upstream and downstream countries has led to benefit sharing and improved international relations throughout the river basin. In this presentation, we introduce a socio-hydrological model that simulates the hydrological changes in downstream countries resulting from upstream dam operation, based on collection of hydrological, economic and social data in Lancang-Mekong river basin. Our model captures the cooperation and conflict feedback loops which impacts the operation rules of upstream dams. In this way, our study generates understanding of the connections between water resources management and hydro-political dynamics underpinning cooperation and conflicts mechanism in this transboundary river basin.