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.

Climate Change and Overuse: Water Resource Challenges during Economic Growth in Coquimbo, Chile

The arid Coquimbo region of Chile has experienced a significant economic growth in recent decades, fueled in large part by water-intensive activities such as mining and agriculture. Under this context, a monthly and annual trend analysis of precipitation, streamflow, and piezometric levels was carried out. Thus, 43 pluviometric stations, 11 fluviometric stations, and 11 wells were selected. These stations were evaluated for their temporal trends using the Mann–Kendall test. Results revealed a significant decrease in river flows, with negative and significant trends concentrated in the mean and maximum flows, both at annual and monthly levels. Likewise, positive trends were found in the depth to water table on wells, with significant trends in 81.8% of the monthly cases, and in 72.7% of the annual cases. While also decreasing over the same period, rainfall trends exhibit high variability and lacked significance. Although the amounts of precipitation have decreased, this does not seem to be the main factor responsible for the scarcity of water in the region, but rather an excessive consumption of this resource. This is endorsed by the increase in GDP (Gross Domestic Product), which is explained by activities that consume water (mining and agriculture). Similarly, an increase in the granting of underground water rights was verified, which speaks of the high demands for the resource. However, future modeling is advised to better understand the regional hydrology of the area and quantify the anthropic effects on water resources more precisely.

Threshold effects of economic growth on water stress in the Eurozone

This paper empirically examines the environmental Kuznets curve (EKC) hypothesis using a country's water stress as an indicator of the pressure on renewable water resources. The sample consists of 9 European countries by covering the period 1995-2013. The paper adopts a panel threshold regression model which can predict the threshold level endogenously to analyze whether income per person has an impact on water stress. The empirical findings strongly demonstrate the existence of a threshold beyond which environmental pressures of GDP (real) per capita growth on renewable water resources tend to increase. The growth below the threshold levels has no statistically significant effect on water stress, while the growth rate above the threshold increases stress on water resources. The available empirical findings obtained, albeit limited, tend not to support the EKC hypothesis, which postulates an inverted-U-shaped relationship.

Retrospective and prospective analysis of water use and point source pollution from an economic perspective-a case study of Urumqi, China

Using the Environmental Kuznets Curve (EKC) hypothesis, this study explored the dynamic trends of water use and point source pollution in Urumqi (2000-2014) from an economic perspective. Retrospective analysis results indicated that total GDP and GDP per capita increased around tenfold and a fivefold since 2000. Total, municipal and industrial water use had average annual growth rates of 3.96, 7.01, and 3.69%, respectively. However, agricultural water use, emissions of COD and NH₃-N showed average annual decreases of 3.06, 12.40, and 4.74%. Regression models reveal that total water demand in Urumqi would keep monotonically increasing relationships with GDP and GDP per capita in the foreseeable years. However, the relations of specific water usage and economic growth showed diverse trends. In the future, the discharge of COD and NH₃-N would further reduce with economic growth. It could be concluded that Urumqi has almost passed the stage where economic growth had caused serious environment deterioration, but the increasing water demand in Urumqi is still an urgent problem. The obtained results would be helpful for water resources management and pollution control in the future.