Relationship between urbanisation and pollutant emissions in transboundary river basins under the strategy of the Belt and Road Initiative

Convergence study of water pollution emission intensity in China: evidence from spatial effects

One of the challenges that China currently faces is how to reduce the emissions of water pollution. However, the study of water pollution convergence has a certain policy significance for controlling the emissions of water pollution. This article firstly uses chemical oxygen demand (COD) and ammonia nitrogen (NH₃-N) as indicators of water pollution. Due to the obvious spillover effect of water in space, this article adds a spatial effect to the convergence model. Based on panel data of 30 provinces and cities from 2006 to 2017, this article uses a dynamic spatial Dubin model to analyze the convergence of water pollution emission intensity to address the endogenous problem in the model. The empirical results of this paper show that there is absolute β-convergence and conditional β-convergence in the intensity of water pollution emissions. The spatial autocorrelation test shows that there is a positive spatial autocorrelation of water pollution emissions, which means that the pollution emissions in neighboring areas will affect the emissions in the local area. The industrial structure has a certain promoting effect on the emission of water pollution, which means that adjusting the industrial structure and alleviating the structure of the secondary industry is the trend of future development. Economic growth can curb the emissions of water pollution. The influences of urbanization and foreign investment on the emissions of the two pollutants are inconsistent, and policies can be formulated according to local conditions in the future.

Gazing into the Crystal Ball: A Review of Futures Analysis to Promote Environmental Justice in the UK Water Industry

Water is a vital and multifunctional resource for our society, economy and ecosystems; thus, how water is managed now and into the future has wide-reaching consequences. Sustainable water management and environmental justice therefore become key topics; a discussion of these terms is explored in the context of the UK water industry, which provides the focus for this study. This systematic review explores how considerations of the future have been applied in water research. The literature is reviewed with respect to (1) defining the end goal, (2) the use of futures analysis and (3) possible evaluation methods, including a discussion on the boundaries applied to each of the studies. A growing body of research associated with decision-making applying future scenarios was identified. However, the methods of application varied substantially, with holistic analyses largely lacking. The formulation of methods appears to be specific to the goal that is sought as well as the cultural influence of the region in which the analysis was developed and deployed. This paper presents a case for the visualisation of catchment characteristics and interdependencies to enable transparency in decision-making. This should reflect not only the current system but also a range of potential futures to enable appraisal of impacts.

Coordination Study on Ecological and Economic Coupling of the Yellow River Basin

The coupling and coordination relationship between ecology and the economy in the Yellow River Basin is a hot topic in sustainable development research. Said research has important guiding significance for the ecological security and comprehensive development of the Yellow River Basin. Taking the Yellow River Basin as the object of our study, based on the data of the economy, energy consumption data, ecology data and water resources data, we construct an indicator system of the economic development and ecological status of the Yellow River Basin and use the principal component analysis method to calculate the economic development and ecological status index. Then, we use the evaluation method, the coupling degree model and the coupling coordination degree model to analyze the time and space evolution trends of economic development and ecological state, coupling degree and coupling coordination degree. The results show that: (1) From 2000 to 2018, the economic development index of the Yellow River Basin rose steadily; the ecological status index showed a slow rise and then a downward trend. (2) The degree of coupling between economic development and ecological state has been considered as intensity coupling after 2005. The coupling trend slowly increased and then decreased, indicating that the interaction effect between the economy and ecology was first significantly enhanced and then slowly weakened. (3) The degree of coupling coordination increased from 0.2994 to 0.6266 and then decreased to 0.5917, reflecting the continuous improvement of the relationship between the regional economy and the ecological environment and the trend toward coordination. From 2015 to 2018, due to the gradual increase in the difference between economic development and ecological conditions, the coupling and coordination between the two decreased. Studies have shown that ecological construction and protection should be strengthened to ease the contradiction between the economy and ecology and achieve coordinated development.

Transboundary Basins Need More Attention: Anthropogenic Impacts on Land Cover Changes in Aras River Basin, Monitoring and Prediction

Changes in land cover (LC) can alter the basin hydrology by affecting the evaporation, infiltration, and surface and subsurface flow processes, and ultimately affect river water quantity and quality. This study aimed to monitor and predict the LC composition of a major, transboundary basin contributing to the Caspian Sea, the Aras River Basin (ARB). To this end, four LC maps of ARB corresponding to the years 1984, 2000, 2010, and 2017 were generated using Landsat satellite imagery from Armenia and the Nakhchivan Autonomous Republic. The LC gains and losses, net changes, exchanges, and the spatial trend of changes over 33 years (1984–2017) were investigated. The most important drivers of these changes and the most accurate LC transformation scenarios were identified, and a land change modeler (LCM) was applied to predict the LC change for the years 2027 and 2037. Validation results showed that LCM, with a Kappa index higher than 81%, is appropriate for predicting LC changes in the study area. The LC changes observed in the past indicate significant anthropogenic impacts on the basin, mainly by constructing new reservoir dams and expanding agriculture and urban areas, which are the major water-consuming sectors. Results show that over the past 33 years, agricultural areas have grown by more than 57% from 1984 to 2017 in the study area. Results also indicate that the given similar anthropogenic activities will keep on continuing in the ARB, and agricultural areas will increase by 2% from 2017 to 2027, and by another 1% from 2027 to 2037. Results of this study can support transboundary decision-making processes to analyze potential adverse impacts following past policies with neighboring countries that share the same water resources.

Coupling coordination and spatiotemporal dynamic evolution between urbanization and geological hazards-A case study from China

Investigation of the coupling coordination between urbanization and geological hazards is an important component in fostering environmentally sustainable development. This study constructed the comprehensive index system and developed the improved coupling coordination degree (CCD) model, Moran's I and projection pursuit model based on genetic algorithm to quantitatively investigate the dynamic mechanism and spatiotemporal distribution of coupling coordination between two subsystems within the context of the Five-Year Plan. Results showed that the comprehensive level of urbanization subsystem followed a continuous upward trend, and the geological hazard subsystem changed from a decreasing (2000-2010) to a rising (2011-2017) trend. A U-shaped relationship existed between two subsystems. And the CCD between two subsystems was higher in northeastern than that in southwestern China. Moreover, the significant spatial dependency existed in CCD. Driving by terrain, rainfall, vegetation cover, and human activities, the provinces in southwestern China exhibited low-low (L-L) clustering, while that in northeastern China showed high-high (H-H) clustering. In the past 17 years, the provinces in transitional and balanced development increased by 14.7% and 8.8%, and that in unbalanced development decreased by 23.5%. Overall, the provinces with low CCD were shrinking and the provinces with high CCD were extending from northeastern to southwestern China, meaning that the state of coupling coordination was changing from unbalanced to transitional development.

Advances in Modelling and Prediction on the Impact of Human Activities and Extreme Events on Environments

Fast urbanization and industrialization have progressively caused severe impacts on mountainous, river, and coastal environments, and have increased the risks for people living in these areas. Human activities have changed ecosystems hence it is important to determine ways to predict these consequences to enable the preservation and restoration of these key areas. Furthermore, extreme events attributed to climate change are becoming more frequent, aggravating the entire scenario and introducing ulterior uncertainties on the accurate and efficient management of these areas to protect the environment as well as the health and safety of people. In actual fact, climate change is altering rain patterns and causing extreme heat, as well as inducing other weather mutations. All these lead to more frequent natural disasters such as flood events, erosions, and the contamination and spreading of pollutants. Therefore, efforts need to be devoted to investigate the underlying causes, and to identify feasible mitigation and adaptation strategies to reduce negative impacts on both the environment and citizens. To contribute towards this aim, the selected papers in this Special Issue covered a wide range of issues that are mainly relevant to: (i) the numerical and experimental characterization of complex flow conditions under specific circumstances induced by the natural hazards; (ii) the effect of climate change on the hydrological processes in mountainous, river, and coastal environments, (iii) the protection of ecosystems and the restoration of areas damaged by the effects of climate change and human activities.

Emergency material location-allocation planning using a risk-based integration methodology for river chemical spills

It is critical for emergency material preparedness in the pre-accident phase to provide location-allocation planning and improve rescue capacity in an effective emergency response time due to increasing frequency of river chemical spills. In this study, an effective two-stage evaluation and selection framework is developed integrating fuzzy multi-criteria decision-making (MCDM) method and multi-objective optimization model to obtain the optimal emergency material location-allocation (EMLA) scheme for coping with river chemical spills. In the evaluation stage, the emergency material warehouse alternatives are evaluated by a fuzzy TOPSIS method based on environmental risk assessment. In the selection stage, the EMLA optimization scheme is identified by a multi-objective optimization model to allocate emergency materials for all the risk sources in a time-effective manner. The two-stage evaluation and selection framework is then applied in Jiangsu province, China. The EMLA optimization scheme finally selects the best five emergency material warehouses (WZ1, WZ 4, WZ 5, WZ 18, and WZ 25) for Jiangsu province with the relative closeness 0.6014, 0.4676, 0.5179, 0.3360, and 0.2935, respectively. The EMLA results demonstrate that the developed framework could obtain EMLA optimization scheme with the objective of minimum emergency rescue points and maximum integrative rescue abilities and provide all the risk resources emergency materials in a quick response for river chemical spills in the pre-accident phase.

The Driving Forces of Point Source Wastewater Emission: Case Study of COD and NH4-N Discharges in Mainland China

Excess consumption of water resources and environmental pollution have become major challenges restricting sustainable development in China. In order to prevent the pollution of water resources, policymakers should have reliable emission reduction strategies. This paper aims to contribute new knowledge by analyzing the spatial-temporal characteristics and driving forces of point source emission. The chemical oxygen demand (COD) and ammonia nitrogen (NH₄-N) emission variations in 31 provinces and municipalities of mainland China during the years 2004–2017 are analyzed. The results obtained using the logarithmic mean Divisia index (LMDI) method indicate that: (1) the COD and NH₄-N emission effects have similar temporal characteristics. Technology improvement and pollutant emission intensity are the main factors inhibiting the incremental COD and NH₄-N emission effects, while economic development is the main driving factor of COD and NH₄-N emission effects. Population increases play a relatively less important role in COD and NH₄-N emission effects. (2) The spatial features of COD and NH₄-N emission effects show differences among provinces and municipalities. The reduction of COD emission effects in each province and municipality is obviously better than that of NH₄-N emissions. (3) In the eastern, central, and the western regions of China, the total COD emission effect shows a downward trend, while apart from the central region, the NH₄-N emission effect appears to be rising in the east and west of China. Therefore, increasing investment into pollution treatment, promoting awareness of water conservation, strengthening technological and financial support from the more developed eastern to the less developed central and western regions, can help to reduce the COD and NH₄-N emissions in China.

The Spatial and Temporal Research on the Coupling and Coordinated Relationship between Social Economy and Energy Environment in the Belt and Road Initiatives

The Belt and Road Initiative (BRI) was presented by China’s central government to achieve regional economic cooperation under the background of economic globalization. Energy and environmental problems, as by-products of economic success, are fundamental concerns in this grand project. An integrated method that combined the coupling coordinated degree model, Moran’s I, and the spatial panel data model was used in the research zone. Results of the coupling coordinated degree model indicated that the statuses of the social economy and the energy environment of the countries in the research zone improved from 1997 to 2014, with the changes in China and Eastern Europe being particularly significant. From the spatial econometric perspective, the coupling coordinated degrees of the countries in the research zone appeared in the spatial cluster in accordance with Moran’s I. The result of the spatial panel data model indicated that the coupling coordinated degree of one country positively affected those of its neighboring countries.

Pollutant source analysis and tempo-spatial analysis of pollutant discharge intensity in a transboundary river basin

From the perspective of river basin refined management and pollution control of water bodies, a transboundary river basin and its regional pollutant sources are identified and the typical status of discharging processes of different pollutant sources are screened. Then organic connection which can comprehensively reflect and dynamically characterize the discharge of transboundary water pollutants is constructed. In addition, the integrated prediction (IP) model of the transboundary river basin and its regional water pollutants discharge is established. Finally, the dynamic simulation of typical status characteristics of the transboundary river basin and its regional pollutant sources discharge as well as the tempo-spatial changing pattern of pollutant discharge intensity is conducted in this paper. This paper selected the Songhua River basin as an example where planting, industry, household (urban living and rural living), and livestock and poultry are the main pollutant sources. The dynamic simulation of water pollution discharge in Songhua River basin during the 13th Five-year Plan and its tempo-spatial changing trend analysis are conducted by employing the established IP model of transboundary river basin water pollution discharge. The results show that during the 13th Five-year Plan, through comprehensive management and control of pollutant sources in Songhua River basin, the discharge amounts of different pollutant sources (planting, industry, household, livestock, and poultry) present an overall decreasing trend and the main pollutants discharge intensity decreases significantly year by year. It is demonstrated that pollution discharge in Songhua River basin is controlled effectively.