Progress in Water Footprint Assessment: Towards Collective Action in Water Governance

A novel framework reveals anthropogenic stressors of phosphorus polluted river-lake connection water system in Poyang lake basin of China

Poyang lake (PYL), as China's largest freshwater lake, has been suffering from increasing total phosphorus (TP) pollution associated with rapid basinal socio-economic development. However, anthropogenic phosphorus stressors were rarely examined in PYL basin due to its large-scale and complex river-lake connection water system, hampering phosphorus pollution control efforts. In this study, water pollution stress from multiple anthropogenic activities is quantitatively examined in PYL basin based on a newly developed framework coupling grey water footprint (GWF) analysis with the SPARROW model. Results show that the phosphorus source-sink process in PYL basin has been well simulated by SPARROW model quantifying an overall TP delivery rate of 0.39, with catchments closer to PYL showing higher delivery rate of phosphorus (up to over 0.8). The GWF analysis demonstrates that anthropogenic phosphorus sources have imposed much higher pollution stress on PYL than its inflowing rivers, with twelve catchments nearby PYL identified as critical source areas of TP contamination. Agricultural farming, livestock & poultry production, and urban household are recognized as the dominant anthropogenic stressors burdening water environment of PYL. Based on these, policy recommendations are provided for advancing control of the phosphorus pollution stressors. The methodology is effective in refined examination of water pollution sources, which is expected to be applied in other watersheds providing informative diagnosis of water issues especially in lakes.

Letter to the Editor

A paper recently published entitled "Water crisis in Iran: A system dynamics approach on water, energy, food, land, and climate (WEFLC) nexus" (Barati et al., 2023). In the mentioned study, a WEFLC model is developed to analyze the water scarcity in Iran. Water crisis, as a complex and challenging issue, has different interdependencies in the context of socio-ecological systems (SES), making it an incorrigible issue. The original paper attempted to assess the water resource dynamics through a systemic lens and explore the impact of various driving forces of water resource planning and management on the water crisis. Iran is a well-studied country, especially around water-related problems. Many interesting facts and findings through the water scarcity analysis in the context of WEFLC are mentioned in the original paper. For instance, it is highlighted that "Mitigation and adaptation policies must be system-oriented and coherent at sectors." However, the original paper did not benefit enough from the previous studies and the full potential of available data. Moreover, some arguments contradict previous findings and, in some cases, are logically flawed. The original paper barely alludes to the nonlinear functional relationships among the components of WEFLC, the core expected component in complex system analysis. Incorrect problem statement formation, flawed methodology, insufficient information on the applied method, ambiguity in models' coupling or cohesion, lack of rational explanation, and inappropriate interpretations of abnormal findings may even mislead many readers. This paper aims to point out some concerns related to the problems mentioned above in the published study, with suggestions to improve the current study and methodological notes for future research.

Water-related limits to growth for agriculture in Iran

Globally, agriculture is the primary water consumption sector. This study used water footprint (W F ) as a bottom-up tool and satellite imagery as a top-down tool to estimate the internal water use (W U ) in the agricultural sector in an innovative way to show the effects of water-intensive use in agriculture in an arid country. The W F of Iran has been quantified for 19 main crops and for related agricultural products exported from Iran to partner countries. Using a bottom-up approach, Iran's total yearly agriculture net water consumption is estimated to be 42.43 billion cubic meters (BCM) per year. Out of 42.43 BCM total net internal water use, only 1.61 BCM is virtual-water export related to these 19 products, and the remaining 40.82 BCM is for internal use. Our results using satellite imagery show that in case of using all possible lands for agriculture, it would require 77.4 BCM. However, not all these lands are within human reach, and the maximum available water is way lower than this amount. Using satellite imagery, the total evaporation from agricultural lands shows 55.27 BCM for 2020, which agrees with national reports during 2005-2014. This study shows that agricultural water consumption tends to use internal water resources at a maximum level for export and national use, significantly impacting renewable and non-renewable water resource availability, especially in groundwater.

A Water Footprint Management Construct in Agri-Food Supply Chains: A Content Validity Analysis

Common problems when carrying out water footprint (WF) assessments are obtaining specific primary data, dealing with the complexity of its computation, and the availability of quality data. In a supply chain context, inconsistencies are even more exacerbated. In order to fill in this research gap, this study proposes and evaluates the content validity of a survey scale to assess WF management initiatives implemented by companies, with a focus on supply chains and the agriculture industry. In order to do so, a literature review was performed to identify candidate survey items whose content was later validated with experts in terms of their relevance, clarity, and essentiality to measure WF management. Content validity was assessed using several indices (items’ content validity index (I-CVI), Kappa’s coefficient, Aiken’ V coefficient, and content validity ratio (CVR)), which indicated high content validity for the selected items. This study provides a set of measurement survey items that can be used to evaluate WF management initiatives implemented in agri-food supply chains in future empirical studies.

Using water footprint concepts for water security assessment of a basin under anthropogenic pressures

The evaluation of water shortages and pollution levels is crucial for watershed management and sustainable development. This paper proposes a water footprint (WF) sustainability assessment approach to analyse water security in a river basin under human pressures. The methodology involves a comprehensive assessment of the current water security at different spatial and temporal levels, and identifies suitable response formulations to achieve sustainability. Field surveys and measurements (streamflow, water quality) were carried out, and the Soil and Water Assessment Tool model was used for assessing water balance components and water quality. The study was carried out in the Canale d'Aiedda river basin (Taranto, Italy), which is part of the 'area of environmental crisis' of Taranto, which requires remediation of surface water, groundwater, soil and subsoil. Considering all the anthropogenic activities in the basin, including agriculture and the treated effluent disposed of via wastewater treatment plants (WWTPs), the average WF was 213.9 Mm³ y^-1, of which 37.2%, 9.2% and 53.6% comprised respectively for WF_green, WF_blue and WF_grey. The WF sustainability assessment revealed that pollution was the main factor affecting surface water security. In particular, point sources contributed with 90% to the total WF_grey, and lower pollutant thresholds should be fixed for effluent from WWTPs in order to increase water quality of the receiving water body. In addition, for assuring water security the extension of the natural areas should be increased to support biodiversity in the river basin and soil management strategies should be improved to allow more water to be retained in the soil and to reduce nutrients in surface runoff. This study demonstrates that the WF sustainability assessment is a feasible approach for integrated water resources management, as well as offering a much broader perspective on how water security can be achieved in a Mediterranean basin affected by multiple anthropogenic stressors.

Past, Present, and Future of Virtual Water and Water Footprint

Virtual water and water footprint have received increasing attention. However, no published research has conducted a quantitative and objective review of this field from the perspective of bibliometrics. Therefore, based on the Web of Science Core Collection, this study employs CiteSpace to quantitatively analyze and visualize information about countries, institutions, and authors that have conducted virtual water and water footprint research over the past two decades. As of July 2020, there were 1592 publications on virtual water and water footprint, showing an increasing trend overall. The annual average number of publications was only 7.4 in 1998–2008, while it was 126.5 in 2009–2019. Among them, up to 618 publications in the field of environmental science, accounting for 46%. China was the most productive country with a total of 344 articles, but the Netherlands had the strongest influence with a betweenness centrality of 0.33, indicating its leading position. It is essential to strengthen cooperation between developed (water-rich) and developing (water-poor) countries and to incorporate virtual water into social water cycle research. This study is expected to provide a new perspective for investigating the research frontiers and hot spots of virtual water and water footprint research.

A New Model-Based Approach for the Evaluation of the Net Contribution of the European Union Rural Development Program to the Reduction of Water Abstractions in Agriculture

Agriculture is an essential driving force in water resources management and has a central role in the European Union’s Rural Development Programme (RDP). In this study, the solution developed addresses countries characterised by relatively small farms, vast spatial and temporal variability and severe data scarcity. The proposed model-based approach is directly relevant to the evaluation of agricultural policies affecting water abstraction based on multisource data. The evaluation process utilises an entirely spatially distributed, continuous hydrological model. The model provides a gridded output of the main hydrological balance components, as well as vegetation water deficit and irrigation water requirements, on a daily temporal step on a country scale. It provides information at the farm level and facilitates the estimation of water abstractions in agriculture, taking into consideration all the pertinent information included in the Integrated Administration and Control System database that is maintained by RDPs in Europe. Remote sensing data also are used to validate crop patterns. The obtained results were analysed to estimate the net effect of the RDP to the reduction of water abstractions in agriculture. This work produces valuable information concerning the evaluation of agricultural policies and the assessment of land use, and climate change adaptation and mitigation strategies.

Citizen and Educational Initiatives to Support Sustainable Development Goal 6: Clean Water and Sanitation for All

Sustainable Development Goal 6 affirms the need to “ensure water availability, sustainable water management and sanitation for all” and thereby highlights a current problem in Spain caused by climate dynamics in the south and southeast of the peninsula and the islands. This study is based on a non-probabilistic online survey with 455 participants (n = 455) carried out to identify citizens’ views across the Autonomous Communities and detect good and bad practices, including efficiency gains and specific problems, derived from water management. Differences in perceptions were found regarding place of residence, gender, and education level, which were all especially significant in relation to territory. Generally, people who live in areas with greater water abundance are less aware of the need to make good use of it. There are no major differences in terms of gender, although there is a greater awareness among women about the effects of climate change and the need for good water management. It is argued that education should employ innovative materials and pedagogically motivating resources from school to university levels.

A Water Footprint Review of Italian Wine: Drivers, Barriers, and Practices for Sustainable Stewardship

Wine constitutes the dominant Italian agricultural product with respect to both production quantity and economic value. Italy is the top wine producer worldwide in terms of volume and the second one below France in terms of national income. As the Italian agricultural production accounts for 85% of the national freshwater appropriation, the country’s agricultural sector strains freshwater resources, especially in the central and southern regions, which constitute important winemaking areas in terms of quantity and quality. To this end, we first perform a review of the existing research efforts on wine water footprint assessment to investigate the water dynamics of wine production in Italy compared to the rest of the world. The results indicate a prevalence of studies on the water footprint of Italian wine, emphasising the need for deeper research on the sector’s water efficiency. Then, we aim at exploring the major drivers, barriers, and good practises for systematic water stewardship in the Italian winemaking industry, considering the product and territorial characteristics. This research is anticipated to contribute towards providing insights for practitioners in the Italian wine sector to develop water-friendly corporate schemes for enhancing the added value of their products.

Decoupling Analysis of Water Footprint and Economic Growth: A Case Study of Beijing-Tianjin-Hebei Region from 2004 to 2017

The Beijing-Tianji-Hebei region (BTHR) is economically developed and densely populated, but its water resources are extremely scarce. A clear understanding of the decoupling relationship between water footprint and economic growth is conducive to facilitating and realizing the coordinated development of water resources and economic growth in this region. This study calculated the water footprint and other related indicators of BTHR from 2004 to 2017, and objectively evaluated the utilization of water resources in the region. Then, logarithmic mean divisia index (LMDI) method was applied to study the driving factors that resulted in the change of water footprint and their respective effects. Finally, Tapio decoupling model was used to research the decoupling relationships between water footprint and economic growth, and between the driving factors of water footprint and economic growth. There are three main results in this research. (1) The water utilization efficiency in BTHR continues to improve, and the water footprint shows a gradually increasing trend during the research period, among which the agricultural water footprint accounts for a relatively high proportion. (2) The change of water footprint can be attributed to efficiency effect, economic effect, and population effect. Furthermore, efficiency effect is the decisive factor of water footprint reduction and economic effect is the main factor of water footprint increase, while population effect plays a weak role in promoting the increase in water footprint. (3) The decoupling status between water footprint and economic growth show a weak decoupling in most years, while the status between water footprint intensity and economic growth always remains strong decoupling. Moreover, population size and economic growth always show an expansive coupling state. In sum, it is advisable for policy makers to improve water utilization efficiency, especially agricultural irrigation efficiency, to raise residents' awareness of water conservation, and increase the import of water-intensive products, so as to alleviate water shortage and realize the coordinated development of water resources and economic growth in BTHR.