RESUMEN

To deepen the recognition of changes in industrial water use with socio-economic development, a "double-layer nested" structural decomposition analysis has been proposed to decompose the influence of the drivers of industrial water use change by sectors in China from 2002 to 2020. The results showed that the scale expansion factors represented by consumption, investment, and export were the main factors for the growth of industrial water use in different sectors, among which the expansion effect of per capita consumption grew faster. Additionally, there were obvious differences in the major drivers of industrial scale expansion between different sectors, which directly drove the industrial structure change. The production process water use effect and water reuse effect were the main factors to curb the growth of industrial water use. The accumulation of both had completely offset the positive effect of industrial scale expansion during the period, reducing industrial water consumption by 11.2 billion m3. However, the production process water use changes in metal extraction, smelting, and processing and energy processing sectors such as electric power had a smaller negative effect, leading to the potential for improving industrial water efficiency solely through a relatively small improvement in water resource reuse. Therefore, it is necessary to strengthen industrial water conservation management based on the differences in the impact of various sectors to promote the transformation and upgradation of industrial production and consumption structures, and to avoid another increase in industrial water use in China.

RESUMEN

Water resource shortage and water pollution are prominent and urgent resource and environment problems. Industrial water consumption and sewage discharges account for a large proportion of the total sewage discharge of China. Therefore, scientifically regulating the water consumption and sewage discharge of industrial enterprises can effectively alleviate water scarcity and pollution problems. By establishing a multi-agent model, this study simulates the water use behavior of industrial enterprises, exploring the responses of industrial enterprises to a different type of scenarios for water management that can coordinate economic and environmental benefits. The purpose is to reduce the water consumption and pollutant emissions of industrial enterprises while achieving economic benefits, so as to provide policy references for water authorities. The results show that: 1) The three policies of water price, water resource tax and emission reduction subsidy can effectively regulate the water consumption and sewage discharge of enterprises. 2) Water price and water resource tax rate need to be controlled within a reasonable range. Appropriate water price and water resource tax rate can encourage enterprises to increase R&D investment. On this basis, it is suggested to emphasize the two-way influence of the government and enterprises, continue to implement water resources management policies such as water resources tax, so as to promote the balance between ecology and economy.

Asunto(s)

RESUMEN

Despite the great number of applications of bootstrapping data envelopment analysis (DEA) with a one-stage structure, there are limited attempts for approximating the distribution of the DEA estimator considering the two-stage structure across multiple periods. This research develops the dynamic two-stage non-radial DEA model based on smoothed bootstrap and subsampling bootstrap. Then, we run the proposed models on assessing the efficiency of China's industrial water use and health risk (IWUHR) systems and compare them with the bootstrapping results on standard radial network DEA. The results are as follows. (1) The proposed non-radial DEA model based on smoothed bootstrap can adjust original over-estimated and under-estimated values. (2) China's IWUHR system has good performance, and its HR stage performs better than the IWU stage for 30 provinces from 2011 to 2019. The poor performance of the IWU stage in Jiangxi and Gansu needs to be noticed. The provincial differences of the detailed bias-corrected efficiencies expand in the later period. (3) The rankings of IWU efficiency in the three regions are in agreement with that of HR efficiency: eastern, western, and central regions in this order. Particular attention should be paid to the downward trend of the bias-corrected IWUHR efficiency in the central region.

RESUMEN

The essence of efficiency measurement is to model and estimate the performance of a complex system in a comparable form, and the key to modeling is to make the model as close to reality as possible. Based on data envelopment analysis (DEA) methods, this research proposes a layer-by-layer investigation framework for the black box. To illustrate the rationality of this logical framework, this paper presents a triple-opened dynamic recycling model with a series-parallel structure that allows us to assess the efficiency of the industrial water-related system in China. We obtain and compare the system efficiency under different scenarios for opening the black box. The results show that: (1) China's efforts to improve the performance of the resource use sub-stage through industrial production technology and management have been effective. (2) The performance of China's industrial water-related system strongly relates to the water supply subunit with a positive linear correlation. (3) The water supply subunit is the main foot-dragger in the system, and the government needs to place particular attention on improving the performance of labor in this subunit.

Asunto(s)

RESUMEN

Numerous studies have divided industrial water use system into stages of industrial water use (IWU) and wastewater treatment (IWT) subsystems, named as the IWUWT system, yet scant studies have examined its dynamic recycling efficiency with non-discretionary variables. This paper proposes a dynamic two-stage recycling model with non-discretionary variables to compare and analyze the basin differences of the efficiency, and further reveal the driving forces of this efficiency in the Yangtze River basin and Yellow River basin. The results are as follows. (1) The average overall efficiency of the IWUWT system for the 30 provinces during 2011-2018 was 0.79 due to the bad performance of the IWT subsystem with an efficiency score of 0.74, especially for Yunnan and Guangxi. (2) The influence of economic policy uncertainty on circulating industrial water use is more significant in the south basin. (3) Economic development and water use intensity were the main drivers of IWUWT efficiency in the Yangtze River basin, while economic development and environmental consciousness were for the Yellow River basin. The results have important implications for Chinese government and different provinces to improve IWUWT efficiency by policy-making.

Asunto(s)

RESUMEN

Water users can reduce their impact on scarce freshwater resources by using more abundant regional brackish or saline groundwater resources. Decentralized water supply networks (WSN) can connect these regional groundwater resources with water users. Here, we present WaterROUTE (Water Route Optimization Utility Tool & Evaluation), a model which optimizes water supply network configurations based on infrastructure investment costs while considering the water quality (salinity) requirements of the user. We present an example simulation in which we determine the optimal WSN for different values of the maximum allowed salinity at the demand location while supplying 2.5 million m3 year-1 with regional groundwater. The example simulation is based on data from Zeeuws-Vlaanderen, the Netherlands. The optimal WSN configurations for the years 2030, 2045 and 2110 are generated based on the simulated salinity of the regional groundwater resources. The simulation results show that small changes in the maximum salinity at the demand location have significant effects on the WSN configuration and therefore on regional planning. For the example simulation, the WSN costs can differ by up to 68% based on the required salinity at the demand site. WaterROUTE can be used to design water supply networks which incorporate alternative water supply sources such as local brackish groundwater (this study), effluent, or rainwater.

Asunto(s)

RESUMEN

Water is a strategic and basic resource for industrial development. The efficient use of water resources is of great significance for the sustainable development of the economy and society. Dynamic SBM model could overcome the shortcomings of static models and reflect inter-temporal efficiency levels. The kernel density curve is used to fit the distribution pattern of industrial water use efficiency and describe its dynamic evolution. Empirical results show that from 2013 to 2017, under the meta-frontier, the industrial water use efficiency values of Beijing, Tianjin, Shandong, Inner Mongolia, and Shaanxi are all 1, and industrial water use efficiency is high, while the industrial water use efficiency values of Sichuan, Guizhou, Anhui, and other provinces are below 0.3, reflecting the low industrial water use efficiency. From 2013 to 2015, China's industrial water use efficiency generally shows a downward trend but begins to rise in the next 2 years. The kernel density curve generally exhibits a bimodal distribution trend and evolves from a "spike shape" to a "broad peak shape".

Asunto(s)

RESUMEN

Water pollution caused by heavy metal leaves human beings exposed to various health risks. Although many studies have focused on the efficiency of industrial water use (IWU) systems, few studies further address analysis for the harmful effect of heavy metal polluted water on human health. This paper first considers both IWU and healthcare (HC) systems as an integrated two-stage IWUHC system. Detailed efficiencies and its dynamic evolution are further revealed by integrating a dynamic two-stage DEA model within a slacks-based measure and Kernel density estimation. Results are as follows: (1) During 2011-2017, the IWUHC systems for 30 provinces in China have low efficiencies, which may have been caused by the bad performance of HC sub-system. The rankings of the average IWU efficiencies in four regions are in agreement with that of HC sub-system: northeastern, eastern, western, and central regions. (2) Provincial differences of IWU efficiencies are more significant than that of HC sub-system. The two-level distribution of IWUHC efficiencies is not helpful for improving IWUHC efficiencies in the eastern and western regions. (3) Understanding the dynamic evolution of the detailed efficiencies and the key indicator efficiencies provide governments with differentiated and forward-looking suggestions toward promoting IWUHC efficiencies.

Asunto(s)

RESUMEN

This paper investigated the relationships between industrial water use, income, trade, and employment for 17 Taiwanese industries from 1998 to 2015. We explored cross-sectional dependent unit root, panel cointegration, and causality tests to estimate their long-term relationships and causal nexus. There existed long-term equilibrium relationships among the variables. The long-term elasticity estimates of industrial water use with respect to income, squared income, trade, and employment are 4.27, - 0.15, 0.22, and 0.92, respectively. The results do not confirm an inverted U-shaped environmental Kuznets curve. A unidirectional causal relationship is found between water use and income, and a bidirectional causal relationship is identified between water use and employment. Exports cause industrial water use. As expected, both employment and exports lead to income. Hence, policy makers should promote investment into water efficiency and water recycling. Various governments reward firms for water efficiency and lower consumption without negative long-term effects on economic growth.

Asunto(s)

RESUMEN

Water availability, resulting from either a lack of water or poor water quality is a key factor contributing to regional water stress. This study proposes a set of sector-wise characterization factors (CFs), namely consumptive and degradative water stresses, to assess the impact of water withdrawals with a life cycle assessment approach. These CFs consider water availability, water quality, and competition for water between domestic, agricultural and industrial sectors and ecosystem at the watershed level. CFs were applied to a case study of regional water management of industrial water withdrawals in Taiwan to show that both regional or seasonal decrease in water availability contributes to a high consumptive water stress, whereas water scarcity due to degraded water quality not meeting sector standards has little influence on increased degradative water stress. Degradative water stress was observed more in the agricultural sector than in the industrial sector, which implies that the agriculture sector may have water quality concerns. Reducing water intensity and alleviating regional scale water stresses of watersheds are suggested as approaches to decrease the impact of both consumptive and degradative water use. The results from this study may enable a more detailed sector-wise analysis of water stress and influence water resource management policies.