Water-related Ecosystem Services Research Articles

A Refined Supply‐Demand Framework to Quantify Variability in Ecosystem Services Related to Surface Water in Support of Sustainable Development Goals

AbstractAs water‐related ecosystem services (WRES) encounter unprecedented threats with climate change and human activities, it is important to understand the impact of variations in the supply and demand for WRES on Sustainable Development Goals (SDGs). Previous studies commonly overlooked water quality and water‐use sectors when using comprehensive supply‐demand index (SDIcom), defined as the difference between water supply and demand, leading to challenges in applying WRES estimation to SDGs assessment. We constructed a refined supply‐demand framework for WRES, categorizing the water supply by water quality and the water demand by sectors. It allows the calculation of refined supply‐demand index (SDIref), addressing the limitations of SDIcom. Our findings demonstrate that SDIref could be effectively employed to assess SDGs and rectify the overestimation of SDIcom in the case study in Xinjiang. The supply‐demand relationship of water resources indicates surpluses in domestic and industrial water use and deficits in agricultural and ecological water use, with the latter worsening. SDIref is projected to be higher in the scenario with SSP2‐4.5 and high growth rate of irrigation efficiency. Our study suggested informed decisions based on SDG‐specific targets to either maintain or enhance SDG progress scores. The proposed refined supply‐demand framework of WRES established a quantitative link between WRES and human well‐being, providing applicable insights for other ecosystem service assessments in other regions.

Temporal–Spatial Characteristics and Trade-off–Synergy Relationships of Water-Related Ecosystem Services in the Yangtze River Basin from 2001 to 2021

The Yangtze River Basin serves as an essential ecological shelter in China, yet it has encountered escalating aquatic ecological challenges. Exploring the spatial–temporal changes and the trade-off–synergy relationships of water-related ecosystem services (WESs) is necessary for formulating management and planning policies targeting the sustainable development of watersheds. In this study, the InVEST model is utilized to evaluate the spatial–temporal variations in water yield (WY), water purification (WP), and soil conservation (SC) in the Yangtze River Basin using remote-sensed data from 2001 to 2021. The spatial overlay method and a correlation analysis were adopted to reveal the trade-off–synergy relationship among the three WESs. Additionally, we performed a comparative analysis across the grid and sub-basin scales. The results showed that the multi-year average WY, WP, and SC were 536.10 mm, 1.32 kg/ha, and 250.08 t/ha, representing increasing rates of 4.74 mm/a, −0.001 kg/ha/a, and 1.88 t/ha/a, respectively. Moreover, the trade-off–synergy relationships of WESs exhibited spatial variability; specifically, the WY-WP, WP-SC, and WY-SC pairs demonstrated reduced synergy magnitude over time. The WES interactions were stable across the scales of interest, while synergy strength showed noticeable variability. The findings may contribute to the sustainable development of the Yangtze River Basin and enhance the comprehensive management of WESs.

Spatial Correlation between the Changes in Supply and Demand for Water-Related Ecosystem Services

Clarifying the spatiotemporal changes in the supply and demand of water-related ecosystem services (WESs) can provide comprehensive support information for ecological governance decisions. However, the spatial mismatch between the supply and demand of WESs is often overlooked, resulting in a lack of targeted decision-making. At the grid scale, while preserving both natural and social attributes, this study quantitatively analyzed the spatiotemporal changes in the supply and demand of WESs in the Southern River Basin from 2000 to 2020. Ecological zoning was performed based on the temporal changes in WESs supply and demand. The OPGD model was used to investigate the impacts of socio-economic and natural factors on different WESs supply factors and further explore the spatial correlation of WESs supply and demand changes in different zones. The results show that there is significant spatial heterogeneity in the changes in WESs supply and demand. Economic belts and megacities have experienced remarkable changes, with WESs supply decreasing and WESs demand increasing. WESs demand changes significantly affect WESs supply changes. The supply of WESs in all zones is influenced by WESs demand. In the high supply–low demand zone, WY has the highest explanatory power for WESs demand changes. From the high supply–middle demand zone to the low supply–middle demand zone and then to the high supply–high demand zone, the explanatory power of PE for WESs demand changes gradually increases. As WESs demand starts from the middle level, HAI gradually dominates WESs demand changes. The increase in land use changes may promote the impact of WESs demand changes on WESs supply changes. This study contributes to incorporating the supply and demand changes of WESs and their correlations into the ecological protection and restoration system, providing a new perspective and method for regional sustainable management.

Multiscale Analysis for Identifying the Impact of Human and Natural Factors on Water-Related Ecosystem Services

Accurately identifying and obtaining changes in ecosystem drivers and the spatial heterogeneity of their impacts on ecosystem services can provide comprehensive support information for ecological governance. In this study, we investigate the changes in the relationship between human and natural factors and water-related ecosystem services (WESs) in different sub-watersheds across various time periods, focusing on four aspects: single-factor effect, nonlinear effect, interactive effects, and spatial characteristics. Taking the southern basins, which have complex topographic, climatic, and economic characteristics, as a study area, the study area was divided into four sub-basins with different characteristics. WESs of water yield, soil conservation, and water purification were quantified using the InVEST model for five periods from 2000 to 2020, and the OPGD and MGWR models were integrated to assess the impacts of 15 factors on WESs and their spatial characteristics. The results show the following: (1) After comparing the data over multiple time periods, climate factors such as precipitation (0.4033) are the primary factors affecting WESs in the southern basins, and human factors such as construction area (0.0688) have a weaker influence. The direct impact of human factors on WESs is not significant in the short term but increases over time. (2) Different sub-watersheds have different impacts on WESs. For instance, human activity intensity (0.3518) is a key factor affecting WESs in the Inward Flowing Area, while precipitation is the primary factor influencing WESs in other sub-watersheds. (3) Influencing factors and WES changes are often nonlinearly correlated; however, once a certain threshold is exceeded, they may have adverse impacts on WESs. (4) When a single factor interacts with other factors, its explanatory power tends to increase. (5) Compared to traditional methods, the estimation accuracy of MGWR is higher. Intense human activities can adversely affect WESs, while abundant precipitation creates favorable conditions for the formation of WESs. Therefore, integrating long-time-series multi-remote sensing data with OPGD and MGWR models is suitable for identifying and analyzing the driving mechanisms of human and natural factors that influence changes in WESs. Against the backdrop of global change, elucidating the driving factors of ecosystem services can provide crucial insights for developing practical policies and land management applications.

Estimation of Water Yield and Soil Erosion in Samanalawewa Watershed in Sri Lanka using GIS-based InVEST Model

Ecosystem services (ES) are a group of tasks performed by the earth's ecosystems that are required to support life and offer benefits to humanity. Thus, this study explores two of the water-related ecosystem services, water yield, and soil retention that were distributed in the Samanalawewa Watershed (SW) and its eight sub-watersheds in Sri Lanka, over 20 years (2000-2020) with five- year time intervals. Soil and water conservation and water yield play an important role in ecosystem management. Hydrological balance is a crucial component of the hydrological ecosystem services. Assessing water yield and soil erosion are pivotal for watershed management. Thus, this study estimated and mapped the water yield and soil erosion, using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST 3.9.2) Annual Water Yield (AWY) and Sediment Delivery Ratio (SDR) model respectively. According to the obtained results, in 2000, 2005, 2010, 2015 and 2020, the estimated mean annual water yield was 2.62x105, 2.6x105, 3.5x105, 3.58x105 and 2.75x105 m3 ha-1year-1, respectively. Furthermore, the estimated mean annual soil erosion rates for the above- mentioned years were 53.2, 52.9, 69.7, 87.7 and 70.2 t ha-1 year-1. The estimated soil loss values of the SW are 10 to 18 times greater than the soil erosion tolerance (5 t ha-1 year-1) in Sri Lanka. The results show that the years 2015 and 2005 have the highest and the lowest water yield and total soil loss values, respectively. The upper part of the watershed has relatively moderate water yield and soil loss values than the lower part. These findings would be beneficial in developing watershed management strategies and in the implementation of suitable soil and water conservation techniques within the watershed. 
 Keywords: Ecosystem services, InVEST, Samanalawewa watershed, Soil erosion, Water yield

Natural/Small Water Retention Measures: Their Contribution to Ecosystem-Based Concepts

The increasing incidence of droughts and heavy rainfall events is exacerbating conflicts between human and environmental demands for water. However, through providing multiple water-related ecosystem services and benefits simultaneously, Natural/Small Water Retention Measures (NSWRM) can mitigate such competing claims. Thus, they also contribute to the achievement of various Sustainable Development Goals and environmental targets set out in water- and agriculture-related policies of the European Union. In particular, NSWRM provide for the sound management of watersheds, which can significantly contribute to improved water quality and availability—as well as improving the resilience of agriculture and society. This paper demonstrates how NSWRM fit into the framework of ecosystem-based concepts, including Natural Water Retention Measures (NWRM), Green Infrastructure (GI), Sustainable Land Management (SLM), Ecosystem-based Adaptation (EbA), and Nature-based Solutions (NbS). NSWRM, as a distinct concept, bring added value to the other concepts by focussing on easy-to-implement, modestly sized, localised technical solutions to problems associated with water management, sediment, and nutrient loss. Through experience under the EU Horizon 2020 project OPTAIN (“OPtimal strategies to retAIN and re-use water and nutrients in small agricultural catchments across different soil-climatic regions in Europe”), we show what NSWRM are, how they are linked to each of the ecosystem-based concepts, and how they can help add value to these concepts. Fourteen case studies are drawn upon from diverse countries across Europe. As a result of this analysis, we present the potential for the application of NSWRM in the context of these concepts, while helping to identify planning tools, the expertise required, and potential funding mechanisms.

Multiscale effects and drivers of landscape heterogeneity for water‐related ecosystem services in urban agglomerations

AbstractUnderstanding the multiscale impacts and drivers of urban agglomeration landscape patterns for ecosystem services (ESs), especially water‐related ecosystem services (WESs), is essential for the development of regional ecological management. However, the multiscale impacts and driving mechanisms of urban agglomeration landscape patterns for ESs have not been adequately explained. In this study, multivariate data were employed, and the InVEST model, trend test method, coupled GeoDetector and geographically and temporally weighted regression (GTWR) method were utilized to comprehensively explore the spatial and temporal changes in landscape patterns and WESs in the Pearl River Delta urban agglomeration (PRDUA) at various grid and administrative scales from 1990 to 2020 and to determine the driving mechanisms affecting WESs. The results indicated that the variation characteristics of landscape patterns and WESs in the PRDUA were consistent, forming a binary spatial structure of core and peripheral areas in an inverted “U” shape around the estuary of the Pearl River. The relationship between landscape patterns and WESs weakened with the increase of scale, and the correlation coefficient decreased by approximately 0.10 from 5 km to 10 km grid scale. Additionally, precipitation (PRE) was the main factor controlling WESs changes in the PRDUA, explaining more than 50% of the changes in WESs, and the regression coefficients ranged from 0.0825 to 0.1584. Changes in WESs were the result of the combined effects of natural factors, including PRE, landscape pattern, elevation, slope, and socioeconomic factors, such as population and gross domestic product (GDP). Overall, these findings could contribute to optimizing regional landscape patterns and fostering sustainable development of the ecological environment in urban agglomerations.

Predicting water ecosystem services under prospective climate and land-use change scenarios in typical watersheds distributed across China

Water-related ecosystem services (WES) critical to anthropogenic-related water security are being severely degraded, primarily due to climate and land-use change. Clarifying future trends in WES (i.e., water yield and water purification services) will contribute to water resource sustainability. However, most existing studies are single case studies and rarely consider the combined impacts of climate change and land-use change on ecosystem services, resulting in patterns that cannot be adequately summarized. In this study, the “Annual Water Yield” module of the InVEST model was used to estimate water yield and the “Nutrient Delivery Ratio” module was used to analyze water purification services. In order to compare the impacts of different natural conditions and geographic locations on water ecosystem services, 17 typical watersheds throughout China were selected as study areas. Coupled scenarios were also considered when setting climate and land-use scenarios to predict prospective (2020–2100) evolutionary trends in WES. The response of WES under different scenarios was also assessed. Results show that climate change is more likely to affect water yield services than water purification services. The impact of land use on water purification services is more pronounced than its impact on water yield services. Climate change contributed > 90 % to water yields in 15 out of the 17 watersheds, contributed 79.4 % in the Hei River watershed, while only contributing 11.2 % in the Yarkant River watershed. The influence of climate change on total nitrogen (TN) output in eight of the watersheds was greater than that of land-use change, especially in the Min River and Mintuo River watersheds, for which the contribution was > 95 %. Furthermore, water purification services in nine of the watersheds were more affected by land-use change, especially in the Dongting Lake and Hei River watersheds, for which the contribution was > 95 %. The aim of this study is to assist in the planning of sound water resource measures while developing sustainable management strategies to help relevant water resource sectors cope with prospective risks and challenges.

Water-related ecosystem services interactions and their natural-human activity drivers: Implications for ecological protection and restoration

Sustainable development faces the crucial challenge of safeguarding water-related ecosystem services, particularly in arid regions. However, scale-dependent interactions and their influencing factors remain unclear. This study addresses this local gap on the regional level by focusing on ecologically vulnerable mountain areas, employing a comprehensive quantitative and spatial analysis approach, utilizing Spearman coefficient, trade-off/synergy index, and trade-off/synergy criterion, to examine water-related ecosystem services interactions across scales in arid area. Additionally, a Geographical detector was used to identify dominant natural and human activity factors. Finally, we determined ecologically optimal and worst areas and proposed spatial planning and management recommendations for ecological protection and restoration. Key results indicate that: (1) From 1995 to 2015, water yield and nutrient delivery ratio exhibited a declining trend, while soil retention showed an increasing trend, with the weakest nutrient delivery ratio function in the reserve. (2) At the grid scale, there were 2 trade-offs among water-related ecosystem services in 1995, which decreased to 1 trade-off in 2005 and 2015. The synergistic was most prominent near Qinghai Lake, while the trade-off was most obvious in the western mountainous areas. Conversely, the county scale demonstrated synergy. (3) NDVI, slope, and precipitation dominantly influence the spatial heterogeneity patterns of soil retention_water yield, soil retention_nutrient delivery ratio, and water yield_nutrient delivery ratio, respectively, with natural factors outweighing human activities in impacting water-related ecosystem services. This study contributes to the improvement and optimization of ecological environment management decisions.

Understanding the role of innovation systems in PES development: A survey of stakeholder perspectives

Water-related ecosystem services of forest land are essential for human well-being. Their provision is related to forest management practices that forest owners and managers apply. When these preferential management practices increase the operating costs, they should be paid/compensated by users of these services. The research focused on identifying the prerequisites of the innovation systems to support payments for ecosystem services (PES) in Slovakia. We analysed the structure, relationships, and functions of the innovation system as monetary and non-monetary incentives, cooperation support and risk mitigation. We collected data using a standardised questionnaire sent out to stakeholders from forestry, nature protection, water management and civil society. The data was processed with simple descriptive methods commonly used in social studies and survey data processing. The information about the potential supply and demand of water-related ecosystem services were obtained from forest owners and managers makes the PES development in the future more feasible. Results revealed that when developing PES schemes, the coordination of stakeholders should follow settled legislation rules at the national level, which still need to be included. Furthermore, the innovation system should provide mainly monetary incentives to providers of ecosystem services.

Assessment of water-related ecosystem services based on multi-scenario land use changes: focusing on the Poyang Lake Basin of southern China

A scientific understanding of the trends of water-related ecosystem services (WESs) under different scenarios is crucial to improving WESs and maintaining ecological security. However, there is a lack of high-resolution land use simulation and assessment of WESs under the SSP-RCP scenarios, and the impacts of different land-use change (LUC) on WESs are not clear. This study focused on the Poyang Lake Basin (PYLB), utilizing the SSP-RCP scenarios, the PLUS model and the InVEST model to explore the dynamic changes of land use and WESs historically and in the future, and to reveal the impacts of specific LUC on WESs from 2000 to 2020. The results demonstrated that: (1) The forest land increased under both SSP1-2.6 and SSP2-4.5 scenarios but increased first and then decreased under SSP5-8.5 scenarios; Cropland increased significantly under SSP5-8.5 scenarios, and the construction land showed an expansion trend under the three scenarios. (2) From 2000 to 2020, only the water purification capacity decreased, while the rest of the WESs increased. Under the SSP1-2.6 scenario, the overall benefits of the WESs in the PYLB were the highest. (3) Between 2000 and 2020, deforestation in the PYLB brought about the greatest increase in the water yield (+9.06 × 108 m3). The increase in the construction land brought about the most water conservation loss (−18.19 × 108 m3). Additionally, the forest expansion and cropland reduction brought about the largest increase in soil retention (+3.94 × 105 t and +4.79 × 105 t) and enhanced water purification, and the opposite was true for deforestation. The conclusions can provide an important basis for the ecological protection and high-quality development of the PYLB.

People, place, and planet: Global review of use-inspired research on water-related ecosystem services in urban wetlands

Abstract With climate change and urbanization, city planners and developers have increasing interest and practice in constructing, restoring, or incorporating wetlands as forms of green infrastructure to maintain water-related ecosystem services (WES). We reviewed studies that valued in functional or monetary units the water regulation and purification services of urban wetlands around the globe. We used the adaptive management cycle (AMC) as a heuristic to determine the step that a study would represent in the AMC, the connections between the cycle steps that were used or considered, and the stakeholders involved. Additionally, we identified the social, ecological, and/or technological dimension(s) of the environmental stressors and management strategies described by study authors. While use-inspired research on WES occurs throughout the globe, most studies serve to singularly assess problems or monitor urban wetlands, consider or use no connectors between steps, and involve no stakeholder groups. Both stressors and strategies were overwhelmingly multidimensional, with the social dimension represented in the majority of both. We highlight studies that successfully interfaced with cities across multiple steps, connectors, engaged stakeholder groups, and disseminated findings and skills to stakeholder groups. True use-inspired research should explicitly involve management systems that are used by city stakeholders and propose multidimensional solutions.

Characteristics of urban expansion in megacities and its impact on water-related ecosystem services: A comparative study of Chengdu and Wuhan, China

The megacity expansion that continues to occur in developing countries is an unavoidable trend at this stage, yet there exists a dearth of knowledge regarding the comprehensive impacts of urban expansion on water-related ecosystem services (WESs) within these areas. Taking Chengdu and Wuhan, two megacities in the upper and middle Yangtze River Economic Belt in China as the study area, this study first compare the magnitude, rate, spatial divergence, and the mode of urban expansion; then evaluate its impact on three typical types of WESs, i.e., water yield (WY), water purification (WP), and habitat quality (HQ) using spatial econometric models and bivariate Moran’s I. The research findings show that Chengdu’s suburbs tend to experience edge-based expansion along rivers, while Wuhan’s city center also spreads outward in edge-based from the river junctions of the Yangtze and Han rivers. Urban expansion negatively impacts all three types of WESs, and its effect in Chengdu is greater than in Wuhan. WY in the suburbs of Wuhan is severely impacted by urban expansion, while WP in the suburbs of Chengdu is as well. HQ in Chengdu’s city center suffers the largest negative impact. The study also reveals a spatial spillover effect of urban expansion, with extensive negative externalities on all WESs in the city centers of both cities and positive externalities on WY and WP in the southwestern suburbs of Chengdu. Based on these results, we suggest that megacities in developing countries should focus on protecting HQ in the city center and limiting cross-regional edge-based expansion in suburbs. Attention should be paid to the water-ecological protection of the suburb rivers. City managers should consider ecological zoning geared toward the conservation of WESs to address the adverse impacts of expansion.

Responses of soil and water-related ecosystem services to landscape dynamics in the eastern Afromontane biodiversity Hotspot

The investigation of soil and water-related ecosystem services (ES) and recognizing the spatiotemporal effects of land-use and land cover changes (LULC) are essential for the formulation of conservation strategies. The research employed the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and the Revised Universal Soil Loss Equation (RUSLE) models for the assessment of ES. The study was carried out in the Kaffa Forest Biosphere Reserve in Ethiopia, which is part of the eastern Afromontane biodiversity hotspots. The aim of this investigation was to examine and map the temporal and spatial fluctuations in sediment retention, soil erosion, and water yield resulting from LULC modifications between 1986 and 2019, and to provide forecasts for the next three decades. According to the RUSLE analysis, the landscapes exhibited estimated soil losses ranging from zero to 1.5 tons ha-1 yr-1 in 1986, 2009, and 2019, respectively. The mean annual sediment exports for the years 1986, 1999, and 2019 were estimated to be 12.6, 9.9-, and 28.7-tons ha−1, respectively. The water yield of the site experienced a notable increase from 9.8 × 109 m3 in 1986 to 19.6 × 10 9 m3 in 1999, and subsequently rose to 39.3 × 109 m3 in 2019, which is considered to be a disadvantageous to the site. The study found a significant positive correlation between water yield and the expansion of settlement area (r = 0.99, P = 0.015) as well as agricultural land (r = 0.99, P = 0.05). It was also found that significant positive correlation found between vegetation dense area such as forest (r < 0.999, P < 0.001) and shrub & bamboo (r = 0.998, P = 0.036) with sediment retention service. The investigation discovered that there existed tradeoffs between the ES of sediment retention and water yield as the slope increased. The results may be attributed to the presence of dense vegetation cover on the elevated slope regions, rendering them unsuitable for agricultural activities, and the concurrent expansion of arable lands in the lower slope areas, which are flat terrains more conducive to cultivation. The transition from land with more vegetation density to land with lower or no vegetation coverage resulted in an increase in soil loss and water yield, while simultaneously decreasing the sediment retention service. Therefore, the findings can be used as a document to guide decision-makers to design soil-water conservation technologies to enhance the ecological integrity of the biosphere reserve.

Spatiotemporal Variation in Water-Related Ecosystem Services during 2000–2020 and Ecological Management Zoning in the Xiangjiang River Basin, China

Exploring the spatiotemporal distribution and interrelationships among water-related ecosystem services (WESs) and conducting ecological management zoning are crucial for regional sustainable development. Taking the Xiangjiang River Basin (XJRB) as an example, this study first quantified three primary WESs, including water conservation, soil retention, and water purification, from 2000 to 2020. Second, the spatiotemporal variation in the interrelationships among WESs were analyzed using global and local bivariate spatial autocorrelation. Third, a water ecological zoning rule was constructed to divide the watershed into three primary and eight secondary water ecological management zones. The results indicate a strong consistency in the changes in the three WESs throughout the period from 2000 to 2020 in the XJRB. Precipitation patterns and urban expansion were the primary factors affecting alterations in the WESs. Spatial heterogeneity and dependence were evident across these ecosystem services. Both trade-offs and synergies were observed among WESs, with synergies playing a dominant role. Positive synergies occurred primarily in woodlands and grasslands, while negative synergies were observed in cultivated land, water areas, and construction land. Three water ecological management zones, including core water ecological management zones, general management zones, and restoration management zones, were delineated at the grid and country scales according to the aggregation properties of the WESs. Ecological management strategies were proposed for different zones. These findings can offer valuable insights for policy makers in land use planning and water ecological management within the XJRB, and can facilitate similar management endeavors in other regions.

Effects of Restoration and Conservation of Riparian Vegetation on Sediment Retention in the Catchment Area of Corumbá IV Hydroelectric Power Plant, Brazil

Vegetation cover and land use are important factors related to the capacity of ecosystems to provide soil loss regulation and sediment retention services, which are highly relevant for sediment management in watersheds draining into reservoirs with multiple water uses. One way to ensure the protection and recovery of vegetation by landowners in Brazil is the implementation of the federal Native Vegetation Protection Law (NVPL), which designates environmentally sensitive areas as Areas of Permanent Preservation (APPs), aiming to conserve water resources and prevent soil erosion. The benefits of riparian vegetation in the catchment of Corumbá IV Hydroelectric Power Plant (HPP), located in the Brazilian Cerrado, were analyzed considering landscape reconfigurations from a baseline condition (year 2011) in order to account for the recovery of riparian vegetation by the agricultural sector, as foreseen in the NVPL. The Sediment Delivery Ratio (SDR) model from the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) package was used to map and quantify variations in sediment export and sediment retention throughout the catchment. The reduction in annual sediment export in the drainage basin of the Corumbá IV reservoir reached −27% in the scenario where the total deficit of riparian APPs occupied by pasture or agriculture in the baseline map (41.000 ha) are recovered. While 14% of riparian APP are occupied by crops versus 86% occupied by pasture in the drainage basin of the Corumbá IV HPP, the recovery of riparian zones occupied by agricultural activities resulted in the greatest benefits in sediment retention for the reservoir. The methodology employed in this study can support the prioritization of sectoral efforts for the restoration and conservation of native vegetation, considering the highest returns in benefits perceived by water users affected by sediment input in reservoirs. The study’s results reinforce the importance of conserving vegetation in riparian areas and their surroundings for sediment retention, highlighting the role of these areas as assets in providing water-related ecosystem services. For future developments, it is suggested to assess the interconnections among the energy, water, and food sectors to better understand the barriers and challenges to the maintenance and improvement of water-related ecosystem services in the catchment area of Corumbá IV HPP.

A framework of payments for water-related ecosystem services (PWES) based on green water management

Green water describes precipitation that infiltrates into the unsaturated soil layer and returns to the atmosphere via plant transpiration and soil evaporation, which are two functions of the hydrological cycle. Green water provides the basis for timber growth, crop production, and ecosystem services. However, it has not been adequately accounted for in traditional payments for water-related ecosystem services (PWES), which predominantly consider on blue water and hence underestimate the availability of all water resources. In this study, a new framework of payments for green water-related ecosystem services (PGWES) is proposed based on green water management (GWM) and green water compensation (GWC). This framework is constructed with game theory modelling, hydrological simulation and scenario evaluation. Then, the Xiangjiang River Basin (XRB) is used as a case study to test and evaluate the feasibility of the framework. The results of this study are as follows: (a) the framework of PGWES and its game payoff matrix and optimal payoff function are improved by adding the GWM scenarios. This approach can identify the GWC standard and Pareto optimal solution in different GWM scenarios, thereby optimizing the spatial allocation of blue and green water in the river basin and coordinating conflicts of interest between the upstream and downstream. (b) The average Pareto optimal payoffs of the XRB are increased by 4390 million CNY/year under different GWM and GWC scenarios compared to the baseline scenario, and the average GWC standard is 2.41 CNY/m3 or 1305.98 CNY/hm2. The case study indicates that the socioeconomic and ecological benefits for the whole XRB are expected to significantly improve under this framework. (c) Three aspects of managing water resources and conflict of interest issues noted during the study include “broadening water sources”, “saving water resources” and “coordinating water conflict”. Green water resources are an important component in broadening water sources; green water management provides a basic measurement tool for saving water resources; and green water compensation based on game theory offers a possible way to coordinate water conflicts and should be given more attention. In general, the PGWES framework provides a referenced methodology for the efficient development and equitable allocation of blue and green water resources in the river basin; furthermore, this study provides a scientific basis for the theory and methods of PWES, thus enriching this field of research.

Harmonization Approach to Spatial and Social Techniques to Define Landscape Restoration Areas in a Colombian Andes Complex Landscape

Landscape restoration activities must be conducted through a transdisciplinary process, integrating social, economic, environmental, and governance aspects. Combining visions from the natural and social sciences is a challenge in highly complex territories, where unique ecosystem characteristics, economic processes, stakeholders of diverse nature, and different normativity converge. The harmonization of multiple techniques, such as multicriteria spatial analysis, expert knowledge elicitation, and social mapping, allows for an approach to defining landscape restoration areas in complex regions. This paper employs multiple techniques to define ecosystem restoration areas in a complex Colombian Andes landscape, integrating ecological and social components for sustainable development. We observed that areas of high and very high feasibility for ecological restoration, encompassing 179.5 hectares (4.84% of the study area), are predominantly located near primary forests. Although some areas have a low feasibility for conservation processes, they should not be disregarded as they still require protection. Landowners prioritize watershed and soil restoration as the most important landscape restoration activity due to their interest in improving water-related ecosystem services. This proposal enables the identification of areas with a higher restoration potential at the property level, facilitating prioritization and investment allocation for future implementation.

Network analysis of water-related ecosystem services in search of solutions for sustainable catchment management: A case study in Sutlej-Beas River systems, India

Hydrological processes and ecosystem interactions are instrumental in sustaining local populations by providing various water-related ecosystem services (ES). Numerous studies gave priority to the theories and methods of building networks that emphasized different stakeholders. However, little study has examined the complex relationships among water-related ES themselves and how relevant human activities affect ES networks. To narrow this gap, in this study we quantified four critical water-related ES (flood mitigation, hydropower production, soil retention, and water conservation), set up six ES network types based on the synergy relationship, and further explored the effect of human activities on these networks. The results showed that among six ES network categories, networks with four fully linked ES occupied a large percentage of 23.20% while the network with one central ES linking two others accounted for the lowest percentage (9.28%). Compared with other ES, soil retention tended to be less centralized within the networks. In addition, land use intensity was found to greatly influence the ES networks compared with other indicators, especially for less complex networks. Our results highlighted the importance of network analysis in searching solutions for sustainable catchment management.

Does the Value of Water-Related Ecosystem Services Capture Water Scarcity? Application to Rice Farming in the Mekong Delta of Vietnam?

This study utilized the contingent valuation method to estimate the value of water-related ecosystem services (ES) in Vietnam, focusing on provisioning and regulating services for addressing water scarcity (WS) in rice farming. By incorporating gender and climate change perceptions, it expanded the existing literature on valuing river ecosystem services. The findings showed a significant number of households experiencing severe water scarcity in the past five years, with over 70% facing occasional or regular WS in the last 12 months. Rice farmers were willing to adopt coping measures and preventive practices to preserve water-related ES, recognizing their importance for sustaining rice cultivation. Farmers demonstrated willingness to contribute financially to restore and maintain water-related ES in rivers and canals. The median willingness to pay for restoration was VND188,300/ha, with estimated values of US$2,898,133 for a 10% affected area and US$23,185,068 for an 80% affected area over five years. Perception of WS severity and associated risk positively influenced households’ decisions to contribute financially. These findings have policy implications and provide insights for effective coping strategies against WS, enhancing water-resilient agriculture in the Lower Mekong Basin.