Moving to economic growth without water demand growth -- a decomposition analysis of decoupling from economic growth and water use in 31 provinces of China

A simulation and risk assessment framework for water-energy-environment nexus: A case study in the city cluster along the middle reach of the Yangtze River, China

In the Anthropocene, there is a strong interlinkage among water, energy, and the environment. The water-energy-environment nexus (WEEN) has been vigorously advocated as an emerging development paradigm and a global research agenda. Based on the nexus concept, a framework for the WEEN complex system simulation and risk assessment is developed. The three metropolitan areas of the city cluster along the middle reaches of the Yangtze River (CCMRYR) are taken as the objects. Regional policies are combined with generic shared socio-economic pathways (SSPs) to form a localized SSPs suitable for the research region. The dynamic simulation of the WEEN complex system and the risk analysis are carried out with the combination of system dynamics models and copula functions. Results show that: There are obvious differences in water utilization, energy consumption, air pollutant emissions, and water pollutant emissions among the three metropolitan areas. The issue of high carbon intensity in the Wuhan Metropolitan Coordinating Region needs to be emphasized and solved from the perspective of optimizing the industrial structure. Adhering to current development patterns, there will be successive peaks in water utilization, energy consumption, and carbon emissions in Wuhan, Dongting Lake, and Poyang Lake Metropolitan Coordinating Region by 2030, leading to high synergy risks at the systemic level, with maximum values of 0.84, 0.85, 0.62, respectively. A development path based on conservation priorities indicates that future policymaking needs to prioritize a resource-saving and pollution-control development pattern directed by technological upgrading against the backdrop of scarce natural resource endowments. The localized SSPs are a beneficial extension that enriches the narrative of regional-scale SSPs. The evolutionary trajectories and risk assessments of WEEN complex systems under different localized SSPs provide a sweeping insight into the consequences of policy decisions, thus enabling policymakers to appraise policy rationality and implement appropriate corrective measures.

Statistical parametric and non-parametric control charts for monitoring residential water consumption

The adoption of strategies for monitoring water consumption is essential for water resources management, contributing to the promotion of the sustainability in the water sector. Statistical process control (SPC) charts, which are widely used in the industrial sector, are statistical methods developed to improve the quality of products and processes. The application of this method has reached other areas over the last decades and has recently been identified as an option for environmental monitoring. In this context, the application of SPC charts emerges as an option for water consumption monitoring, whether in a building or an urban scale. Thus, this article aims to analyze the application of statistical process control charts in the monitoring of water consumption of two housing compounds in Joinville, southern Brazil. The methodological procedures include the use of the Shewhart and the EWMA control charts in addition to the non-parametric alternative, the EWMA-SN, assessing the effectiveness of these techniques in detecting water leaks in residential apartment buildings. The data sets, obtained through a telemetry metering system from the water utility, represent a period of 243 days. The results show that control charts are a powerful tool in identifying changes in water consumption patterns, with the EWMA chart flagging the leaks sooner.

How does coordinated regional digital economy development improve air quality? New evidence from the spatial simultaneous equation analysis

Countries around the world are increasingly turning towards developing digital economies to find better strategies for tackling the environmental pollution associated with economic growth while also pursuing high-quality economic conditions. This study aims to probe the link between coordinated regional digital economy development (RDEC) and air quality. A province-level RDEC indicator based on city-level data is developed, and air pollution is gauged by annual average PM_2.5 concentrations. Furthermore, a spatial simultaneous equation model is employed to examine the causality further. The empirical results indicate that a bilateral causal relationship exists: RDEC improves air quality, and better air quality also facilitates RDEC. This relationship is influenced by spatial spillover effects. Specifically, air quality and RDEC of an area have a negative influence on the RDEC of neighboring regions, while they have a positive impact on neighboring areas' air quality. Further analysis suggests that green total factor productivity, advanced industrial structure, and regional entrepreneurship level can indirectly affect the contribution of RDEC to air quality. Additionally, the impact of air quality on RDEC may be realized through the increase in labor productivity, lower external environmental costs of regional economic development, and enhanced regional foreign economic exchange.

Coupling coordination and spatiotemporal dynamic evolution of the water-energy-food-land (WEFL) nexus in the Yangtze River Economic Belt, China

The interrelationship between regional water, energy, food, and land systems is extremely complex. Hence, accurately assessing the coupling coordination relationship and identifying the influential factors of the water-energy-food-land nexus (WEFL nexus) are of utmost importance. This study proposes a novel analytical framework and evaluation index system for exploring interactions across the WEFL nexus. The comprehensive benefit evaluation index (CBEI), coupling coordination degree (CCD) model, and obstacle factor diagnosis model are integrated to assess and analyze the coupling coordination relationship and spatiotemporal dynamic evolution of the WEFL nexus in the Yangtze River Economic Belt (YREB) from 2006 to 2020. The results indicated that (1) the CBEI and CCD generally increased from 0.23 to 0.79 and 0.45 to 0.88, respectively, revealing the upward trend of the coordination development levels of the WEFL nexus in the YREB. (2) The lower reaches achieved a relatively higher coordination development degree than the upper and middle reaches of the YREB. (3) The findings of obstacle factors reveal that agricultural non-point source pollution control, waterlogging disaster prevention, industrial solid waste efficient treatment, and urban water-saving are the essential fields that need to be improved in YREB's future development. This study helps to understand the complex interrelation of the WEFL nexus at different spatial-temporal scales and provides a novel framework that can be used as an evaluation system and policy insights for a region's integrated resources, environmental management, and green sustainable development.

Dynamics of the water environment in a water quantity-quality-soil model of China's Yellow River basin: imbalance and driving factors

Dynamic assessment of the water environment reflects variations in water resources in a basin under the combined influence of nature and humans and is a prerequisite for rational water management. This study provides an integrated assessment of the water environment in a water quantity-quality-soil model. Using the long-term monthly data from hydrological monitoring stations, the water environment of the Yellow River basin is assessed from the year 2006 to 2019. The kernel density estimation and the Dagum Gini coefficient are used to analyze the spatial and temporal imbalances of the water environment. Geographic detectors are used to extract external driving factors of the unbalanced evolution. The study results reveal that (1) the water environment in the basin shows a fluctuating downward trend, which mainly depends on the organic pollution control indicators, with a contribution of 22.85%. Scores of the water environment in the midstream are lower than those in the upstream and downstream due to the heavy pollutant discharges. (2) The spatial imbalance shows a fluctuating downward trend. Inter-regional variation is the primary source of regional variation in the water environment, with an average contribution of 56.02%. (3) The temporal imbalance of the water environment is on the rise, with a degree of multipolarity. The significant left trailing feature of the kernel density curve suggests that there are areas within the basin where the water environment is extremely poor. (4) For the overall basin and upstream, economic development and technological innovation are the main external driving factors influencing the spatial and temporal imbalances of the water environment. For the midstream and downstream, population density and environmental regulations are the main drivers. The interaction of any two factors has a greater impact than the single one.

When will China's total water consumption reach the turning point? EKC simulation and influencing factors

The turning point of China's total water consumption is very important for the understanding of the evolution trend of total water consumption and the formulation of water conservation policies. Based on the environmental Kuznets curve (EKC) model, this paper verifies the shape of water consumption Kuznets curve. Scenario analysis and Monte Carlo simulation are combined for the first time to predict water consumption Kuznets curve. The LMDI model is used to decompose the driving factors of the evolution of total water consumption, and the STIRPAT model is expanded to explore the influence mechanism of total water consumption. The results show the following: (1) The theoretical water consumption Kuznets curve exists, and the turning point is 26,448 yuan RMB (in around 2013). (2) Based on the multiple driving factors (water intensity, per capita GDP, and population) and multiple scenarios (baseline scenario, target scenario, and 2 adjusted scenarios), 32 scenarios are designed in this paper; in the S1-S8, the turning point still appeared near 2013; the curves under the S11-S14, S16, and S25-S32 were inverted U-shaped, and the turning point was 48,728 yuan RMB (in around 2025); and in the S9, S10, and S15, the curve shows an upward trend; in the S17-S24, the curve has a rising-falling-rising characteristic. (3) Domestic effect and ecological effect both play a role in promoting the total water consumption, while the production effect is in an inverted N-shaped. Economic growth has always promoted the increase in industrial and agricultural water consumption, and the role of population size is relatively weak. The intensity of production water consumption has always promoted reduction in industrial and agricultural water consumption. Industrial water intensity and industrial structure are the primary and secondary factors that promote the decline of production intensity. (4) The per capita GDP has the largest contribution to total water consumption, followed by the water intensity, and the industrial structure has the least impact. The population has a negative impact. Based on this, a number of policy implications are obtained.

Decoupling of water resources utilization and coordinated economic development in China's Hexi Corridor based on ecological water resource footprint

The rapid growth of population and economy leads to a further increase in demand for water resources. The contradiction between supply and demand of water resources has become the main bottleneck restricting sustainable development of a regional social economy. Accurate measurement of regional water usage and the harmonious balance between water consumption (WC) and economic growth (EG) are the premise of regional high-quality development. Based on this premise, this paper studied the arid oasis region, Hexi Corridor, as the research object; utilized the theory of ecological footprint to calculate the ecological footprint (EFW) and ecological carrying capacity (ECCW) of water resources from 2005 to 2019; and quantitatively analyzed the water utilization situation in Hexi Corridor in the past 15 years. Then, combining with the coordinated development decoupling evaluation model, the connection between WC and EG was evaluated. The main results of this study were as follows: (1) During the study period, EFW has shown a fluctuating downward trend, decreasing from 1.745 in 2015 to 1.588 hm²/person in 2019. The average annual EFW per capita of 10,000 yuan of GDP decreased by 10.18%, which showed that the water resources utilization efficiency was gradually increasing. However, there was still a large water deficit. The average water ecological pressure index was 16.55; water resources were under great pressure. (2) From 2005 to 2019, the relationship between WC and EG experienced stages of strong decoupling-weak decoupling-weak negative decoupling-strong decoupling in Hexi Corridor, and the coordination between the two was gradually strengthened. (3) The decoupling status of the Hexi Corridor cities was gradually optimized. Zhangye was the best and in a stable decoupling state, followed by Wuwei and Jiuquan. The number of decoupling years accounted for 85.7% and 78.6% of the evaluation period, respectively. The cities with poor decoupling status were Jiayuguan and Jinchang, and the number of decoupling years accounted for 71.4% and 57.1%, respectively. This study provides some highlights for the formulation of arid oasis regional water strategy.

Identifying the decoupling pathways of water resource liability and economic growth: a case study of the Yangtze River Economic Belt, China

Identifying the high-quality economic growth pathways under the requirements of water conservation and water pollution reduction is pivotal to realize regional sustainable development. Combined with the theory of resource and environmental value, sustainable development, and environmental accounting, this paper innovatively introduces water resource liability (WRL) to measure water environmental pressure. This study takes the Yangtze River Economic Belt (YREB) as the research area and firstly conducts a spatial-temporal analysis of the WRL change in this region from 2013 to 2018. Then, the Tapio decoupling model is used to analyze the decoupling states and the decoupling stabilities between WRL and economic growth in the 11 provincial areas and 3 sub-regions of the YREB. Finally, the main internal factors affecting the decoupling states are identified from the perspective of decoupling decomposition. The main results show that: (1) The WRL of the YREB increases from 173.36 billion CNY in 2013 to 201.62 billion CNY in 2018, with an increase of 16.3%, showing an upward trend of fluctuation. The WRL of the lower reaches of the YREB is generally higher than those of the upper and middle reaches of the YREB from both the provincial and sub-regional levels. Chongqing has the lowest WRL with an average value of 7.03 billion CNY, while Shanghai has the highest with the average of 28.74 billion CNY. (2) The decoupling state between WRL and economic growth in the YREB is generally stable. The decoupling state of the downstream is better than that of the upper and middle reaches, and the decoupling stability index is 0.59, which is the most stable. (3) The internal influencing factors between WRL and economic development in the YREB include structural effect, technological effect, and silence effect, among which technological effect with the worst decoupling stability is the main driving factor. The findings of this study are crucial for policy makers to formulate targeted policies to decouple WRL from economic growth and to realize sustainable development in the YREB.

Economic and Sustainability Inequalities and Water Consumption of European Union Countries

Water scarcity is becoming a global concern for many reasons as its consumption increases. This research aimed to analyze sustainability inequalities in the water consumption of EU countries. Descriptive statistics using data for four AQUASTAT periods (2002, 2007, 2012, and 2017), and quotients for the AQUASTAT 2017 period, were calculated using a proposed econometric model. The main results were that countries with high GPD and population showed high water stress and total water withdrawal. Countries with lower industry-value-added-to-GDP quotients were among those with higher industrial water use efficiency, while low water-services-use-efficiency quotients were associated with high services value added to GDP. Suggestions for policymakers are provided and formula application guidelines for regional-level comparisons are described.

Does economic growth help reduce inequality of water consumption? Insight from evolution and drivers of inequality in water consumption in China

Achieving equality in water usage is part of the sixth goal of the 2030 Agenda for Sustainable Development. A comprehensive understanding evolution of inequality in water use and the driving factors behind the inequality can facilitate to implement equality in water consumption. In this work, the inequality index was used to measure China's water consumption inequality from 2004 to 2018 and the decomposition technique was used to decompose the status of inequality and the evolution of inequality. The results show the inequality in its water consumption was not reduced obviously despite China's rapid economic growth. There were 38.71% of provinces in China whose per capita water consumption was greater than the national average, mainly in the western region. For the three regions of China, the intraregional inequality was much greater than the interregional inequality. The western index was the largest and the eastern was the smallest. Among the factors that cause the inequality in water consumption, no one factor has been dominant at all times. Moreover, the effects of different factors changed over time. It is almost impossible to reduce inequality in water consumption through policy adjustment to several factors. China's example show that economic development cannot reduce the inequality in water consumption. More targeted policies and more efforts are required to reduce the inequality in water consumption.

An Evaluation of Coupling Coordination between Rural Development and Water Environment in Northwestern China

Balancing the relationship between rural development and the protection of water resources is a challenging undertaking. This study develops a coupling coordination degree (CCD) model to examine the non-linear interaction between rural development and water environment in the 11 prefectures of Gansu, northwestern China. There are three key findings. First, economic development is the key driver of rural development, whereas social development has relatively little impact. For the water environment subsystem, improved water efficiency has been the key contributor, whereas environmental carrying capacity is secondary. Second, the CCD increased steadily in the studied period, which suggests that the relationship between rural development and water environment has gradually changed from antagonistic to mutually beneficial. However, this change is not occurring rapidly and in fact shows signs of slowing. Third, the complex spatial differences of the CCD are related to the level of economic and social development, the process of urban–rural integration, and regional natural conditions. The findings of this study have great significance for further quantitative analysis of the interaction and mutual feedback mechanism between the rural economy and the water environment in China and support evidence-based policymaking.

Driving Factors of Decoupling between Economic Development and Water Consumption in Food and Energy in North-West China—Based on the Tapio-LMDI Method

The shortage of water resources has become a notable bottleneck, restricting the economic development of many countries and areas around the word, especially that of North-west China. The Inner Mongolia Autonomous Region and Shaanxi Province are important energy bases and food production areas in North-west China. However, the region is suffering from perennial drought and water shortage, which has become the most significant shortcoming for energy and food production. Guiding the decoupling between regional economic development and water consumption is a critical way to achieve sustainable development. Based on the analysis of the food and energy production value and their water consumption in North-west China from 2009 to 2019, this paper uses the Tapio model to analyze the decoupling relationship between food, energy production, and water consumption, and uses the Logarithmic Mean Divisional Index (LMDI) model to analyze the driving factors affecting decoupling. The results show that most water consumption for food and energy production in North-west China is out of the ideal strong decoupling, the decoupling status is unstable, and re-coupling occurs frequently. The increase in water intensity and the change in industrial structure are the promoting factors of decoupling between production value and water consumption in food and energy in North-west China, while the increase in production value and population size are the main restraining factors. Therefore, in pursuit of strong decoupling, the government should guide the food and energy industry to move toward implementing in water saving measures through policies and promote the enthusiasm and efficiency of the labor force through financial support and other ways. Moreover, ecological protective measures are needed to be strengthened, such as water source protection, and sewage treatment.

Decoupling analysis of water use and economic development in arid region of China - Based on quantity and quality of water use

Decoupling water use from economic development is a fundamental strategy to improve environmental quality from the source. It can promote economic growth while reducing water use and water pollution. This article uses water footprint theory to calculate the relevant indicators of the water quantity footprint and water quality footprint of the Northwest arid region between 1997 and 2017. This paper not only comprehensively consider the impact rate of economic development on water resource consumption and water pollution, but also analyzes the coordination of water resource utilization efficiency and economic development from the perspective of water resource flow, and make up for the deficiencies of pure consideration of water resource consumption. The results of the study show that in the past 20 years, the water resources utilization and economic development in Northwest arid region of China has shown relatively decoupling and weak negative decoupling, and the decoupling index of water quantity and water quality with economic development are 0.3377 and 0.3156, respectively. It shows that the dependence of economic development on water resources is gradually decreasing. However, the water shortage remains serious, this also shows that the efficiency of water use has not improved. Only if economic development is decoupled from water quantity and water quality at the same time, we can achieve sustainable development of water use and economy. We also found that the proportion of agricultural production water is too large, industrial water consumption is declining, and the proportion of domestic water consumption is increasing. There is a problem of unreasonable utilization structure and it can be seen from the wastewater discharge data that the discharge of industrial wastewater is declining. The government needs to focus on the wastewater treatment, strengthen the awareness regarding of water conservation at same time, and use stepped pricing standards to reasonably control water use.

Impact of coronavirus (COVID-19) spread-prevention actions on urban water consumption

This article aims to assess the impact of coronavirus (COVID-19) spread-prevention actions on water consumption, based on a case study in Joinville, Southern Brazil. Residential water consumption data, obtained through telemetry in two periods (before and after a governmental action imposing quarantine and social isolation), were analyzed. Complementarily, the analyses were also applied to the commercial, industrial and public consumption categories. For the analysis, Wilcoxon and Kruskal-Wallis non-parametric tests were applied and Prais-Winsten regression models were adjusted. The results of the Wilcoxon test show that there are significant differences between the analyzed periods, indicating a water consumption drop in the commercial, industrial and public categories, and an increase in the residential category. The regression model results confirm the effect of the restrictive actions in reducing consumption in non-residential categories. The results also indicate an increase in water consumption, which was steeper in apartment buildings than in houses, whether isolated or grouped in condominiums. A weak association was found between the variation in water consumption and the spatial distribution of buildings. Understanding water consumption related aspects is important to gather essential information to ensure the urban water supply system is resilient in a pandemic situation.

Investigating effect of R&D investment on decoupling environmental pressure from economic growth in the global top six carbon dioxide emitters

This work is aimed to investigate the effect of research and development (R&D) on reduce in environmental pressures through an empirical analysis of the top six global carbon emitters (the C6: China, USA, India, Russia, Japan, and Germany). This work is valuable toward carbon reduction within C6 countries and the world (C6 emit roughly 60% of the global carbon emissions). Moreover, it is also meaningful for exploring the decoupling of economic development from carbon emissions in other areas (both developing and developed countries). The main findings displayed that the decoupling status in developed countries (i.e., USA, Japan, and Germany) were better and more stable than in developing countries (i.e., China, India, and Russia). Germany performed best among the developed countries, and China performed most stable among the developing countries. The effect of the per capita R&D expenditure was main resistance to decoupling carbon emissions from economic development in C6 countries. However, the energy intensity effect and R&D efficiency effect related to technological progress were the main driving forces for the decoupling process. Consequently, this study proposes that the improvement of technological progress should be prioritized.

Decoupling Urban Water Use and Growth in Response to Water Scarcity

Many cities in the western US face difficult challenges in trying to secure water supplies for rapidly growing urban populations in the context of intensifying water scarcity. We obtained annual data from urban water utilities across the western US to document trends in their water usage and service populations. We found that many cities have been able to accommodate population increases while simultaneously reducing their volume of water use, thereby decoupling growth from water use. This outcome is largely attributable to reductions in per-capita residential use. We identify additional untapped potential that can sustain and widen this decoupling for many cities.

Integrating Sustainability Assessment into Decoupling Analysis: A Focus on the Yangtze River Delta Urban Agglomerations

Rapid urbanization has led to a growing number of environmental challenges in large parts of China, where the Yangtze River Delta (YRD) urban agglomerations serve as a typical example. To evaluate the relationship between environmental sustainability gaps and urbanization in 26 cities of the YRD, this study revisited the environmental sustainability assessment (ESA) by combining the metrics of environmental footprints and planetary boundaries at the city level, and then integrated the footprint-boundary ESA framework into decoupling analysis. The results demonstrated considerable spatiotemporal heterogeneity in the environmental sustainability of water use, land use, carbon emissions, nitrogen emissions, phosphorus emissions and PM2.5 emissions across the YRD cities during the study period 2007–2017. Decoupling analysis revealed a positive sign that more than half of the 26 cities had achieved the decoupling of each category of environmental sustainability gaps from urbanization since 2014, especially for nitrogen and phosphorus emissions. On the basis of ESA and decoupling analysis, all the cities were categorized into six patterns, for which the optimal pathways towards sustainable development were discussed in depth. Our study will assist policy makers in formulating more tangible and differentiated policies to achieve decoupling between environmental sustainability gaps and urbanization.