The local coupling and telecoupling of urbanization and ecological environment quality based on multisource remote sensing data

Multiscale exploration of spatiotemporal dynamics in China's largest urban agglomeration: An interactive coupling perspective on human activity intensity and ecosystem health

Human economic construction increasingly impacts highly sensitive ecological zones, weakening ecosystem health in cross-regional urban agglomerations. Exploring the spatiotemporal dynamics of urban agglomerations from the interactive coupling perspective between human activity intensity (HAI) and ecosystem health index (EHI) is crucial for resolving human-land conflicts. This study developed a human-land coupling assessment framework integrating human footprint and ecosystem Maintain-Bearing-Service-Resilience models. Across multiple scales, from urban agglomerations and cities to grid cells, we initially employed exploratory spatiotemporal data analysis techniques to reveal HAI and EHI evolution patterns. Subsequently, we used the four-quadrant model, coupling coordination degree (CCD), and relative development model to explore their spatiotemporal interactions. Applied to China's largest urban agglomeration, the middle reaches of the Yangtze River urban agglomerations (MRYRUA), results revealed a significant spatiotemporal mismatch pattern between HAI and EHI. High HAI and low EHI areas were widely distributed in highly urbanized waterfront plains. At the urban agglomeration scale, HAI and EHI exhibited spatiotemporal differentiation patterns extending toward polarization along the Yangtze River Economic Belt, while their correlation intensity among cities indicated conflicting development patterns. At the grid scale, the spatiotemporal clustering pattern highlighted waterfront built-up areas as HAI hotspots and peripheral forest zones as EHI hotspots. The interactive relationship between HAI and EHI shifted increasingly towards Quadrant IV as HAI rose. The coupling levels between HAI and EHI will tend toward misalignment as urbanization advances, although current CCD shows positive trends. This study offers scientific guidance for achieving sustainable development in urban agglomerations across multiple scales.

The synergies of air quality monitoring program: Information disclosure and pollution control

To deal with the increasingly severe climate crisis and environmental pollution, China launched a nationwide real-time air quality monitoring program in three batches, a milestone moment in its environmental governance history. Using the time-varying difference-in-differences model, this study explores the synergies of this program across 284 cities from 2009 to 2019. The findings are as follows: (1) With environmental information disclosed, the national air quality monitoring program can reduce the outdoor fine particulate matter concentration by an overall effect of 3.31%, equivalent to an almost 1% reduction calculated by its average value. (2) This program can enhance public environmental attention and stimulate environmental practitioners' employment, thereby achieving a synergistic effect on air pollution reduction. (3) The pollution reduction effect is expected to be more pronounced in cities located in the southern and eastern regions, cities with higher population densities, and cities with favourable ventilation capabilities. (4) In response to air pollution problems, the public will adjust their daily consumption patterns to avoid potential health risks. As a result of the short-term behavioural changes, they will be more willing to pay for clean air by purchasing household air purifiers. This study highlights the considerable ecological and economic benefits of environmental information disclosure, thus further contributing to future eco-friendly and sustainable development.

Ecosystem service value in the context of urbanization: Comparison among economic-social regions of Vietnam

Urbanization is one of the important features of socio-economic development and it has a major impact on the value of ecosystem services (ESV). This study aims to quantify ESV for the entire country of Vietnam with the research unit being 6 socio-economic regions. This can be considered the first study in Vietnam to quantify the ESV for the entire country. The study calculated the annual urban land growth index (AI) and the annual urban land expansion rate (AER) to determine the urbanization status in the six study areas. The study collected input data from JAXA for four years: 1990, 2000, 2010, and 2020. Research results show that urban land area tended to increase and forest land area decreased sharply. The AI and AER indicated that the period 2000-2010 was a period of rapid growth in Vietnam. Meanwhile, the ESV for all of Vietnam increased year by year. The period 2000-2010 witnessed a growth in ESV about 2.35 times higher than the period 1990-2000, and about 0.1 % lower than the period 2010-2020. Overall, MKD was the region showing strong growth in ESV from 1990 to 2020. Compared to that, NMR was the region with the largest decline in the 20 years from 1990 to 2010, and CHR in the past 10 years. This research contributes to enriching reference sources for Vietnamese and world researchers to have a broader view of ESV as well as the annual urban growth rate in Vietnam from 1990 to 2020.

Research on the coupling and coordinated development of Guangxi's tourism industry, new urbanization and environmental health system in the post-epidemic era

As one of China's sunrise industries, tourism has always been the engine to promote the development of the national economy, and in 2018, the annual income of China's tourism industry exceeded 5 trillion yuan unprecedentedly. In recent years, the traditional extensive production mode has inevitably brought about problems such as environmental pollution and public health threats, while helping the development of new urbanization, thus triggering a series of challenges in the environmental health system. The tourism industry, new urbanization, and environmental health system three cooperate and promote each other, the coordinated development between them for economic growth, new urbanization development, environmental protection, and public health play a vital role, in the post-epidemic era is a special period of historical opportunities, the public's focus from the original sacrifice of environmental health in exchange for economic growth model began to green, low-carbon sustainable development mode, Guangxi Zhuang Autonomous Region as a tourism resource endowment rich region, It is of positive significance to explore the coupling degree and coordination between the tourism industry, new urbanization and environmental health system, and put forward targeted practical enlightenment, which is of positive significance for promoting the sustainable development of tourism industry. Taking Guangxi Zhuang Autonomous Region as a case study, this paper constructs three comprehensive evaluation index systems of the tourism industry, new urbanization and environmental health system, and analyzes and compares the weights of various indicators in the three fields of tourism economy, new urbanization and environmental health system in Guangxi by using the entropy weight TOPSIS method. The coupling coordination model was used to measure the coupling degree and coordination degree of the tourism industry, new urbanization and environmental health system construction in Guangxi Zhuang Autonomous Region from 2009 to 2021. The empirical results show that the weights of various indicators change with the development of the social economy. The comprehensive efficacy index of Guangxi's tourism industry has increased year by year for 11 consecutive years; At the end of the evaluation period, after the outbreak of the new crown epidemic, the evaluation index of the tourism industry, new urbanization and environmental health system all showed a downward trend to varying degrees. Before the pandemic, the coupling coordination type of the three subsystems generally experienced a transformation of "moderate dissonance-reluctant coordination-primary coordination-intermediate coordination," but the overall development level was still poor. After the outbreak of the new crown epidemic, the coupling and coordination between the three has been reduced to a state of poor coordination. Because of the above research conclusions, this study proposes to make full use of the important time node of the post-epidemic era and proposes to actively promote the development of the tourism industry, promote the upgrading of the industrial structure, use digital empowerment of the economic form, optimize the environmental health system and other targeted countermeasures to keep the coupling degree and coordination between the three within a reasonable range. This ensures the sustainable development of social systems in the region. This study has made some contributions to the development of high-quality tourism and a healthy environment. First of all, it enriches the content of the environmental health system. This study takes the ecological environment and atmospheric environment in the environmental health system as the entry point and adds the index content of the environmental health evaluation system, which provides a certain supplement for the relevant research on the environmental health system strength. Secondly, the relationship between the tourism industry, new urbanization and environmental health is analyzed and into a unified theoretical framework. This study takes the Guangxi Zhuang Autonomous Region, which is rich in tourism resources, as a case study site, and innovatively explores the coupling and coordination relationship among the tourism industry, new urbanization and environmental health system in the case site. Finally, it provides targeted countermeasures for the sustainable development path of the three systems of tourism industry, new urbanization and environmental health in the case site in the future. It is of positive practical significance to compare the coupling and coordination degree between the three, realize the coordinated, orderly, and healthy development of the three in the region, and provide operational suggestions for the upgrading of the tourism industry structure, the benign development of new urbanization, and the formulation of environmental health system policies.

Dynamic evolution and trend prediction in coupling coordination between urban and rural space utilization efficiency based local and tele-coupling model

Optimizing the pattern of territorial space utilization is one of the key tasks to achieve the sustainable development goals. With the accelerating rate of global urbanization, the understanding of territorial space utilization efficiency, role and potential is a prerequisite for alleviating contradictions in urban and rural space distribution. The city cluster is the main form of organization for urban development in future, so the study attempted to explore the urban and rural space utilization efficiency (URSUE) in Chengdu-Chongqing urban agglomeration (CCEC) from coupling coordination degree (CCD) perspective. Considering the gradual increase in the trend of remote interactions between URSUE, we further introduced the Local and Tele-coupling coordination (LTCCD) model that takes into account interactive development relationship between different systems. The results of the study show that: In CCEC, the more economically developed cities indicated that urban spatial utilization efficiency lags behind rural spatial utilization efficiency; The LTCCD in the geographic center region will indicate a higher level but the LTCCD in the economic core cities is higher compared with their CCD level, especially in Chengdu City. This suggests that the LTCCD model is better able to take into account regional development correlations and spatial spillovers effect. This study attempts to explore several key issues of urban-rural spatial allocation in the process of urbanization development and to provide guidance for the territorial space utilization planning in urban agglomerations.

Exploring dynamics relationship between carbon emissions and eco-environmental quality in Samarinda Metropolitan Area: A spatiotemporal approach

Carbon emissions have a negative impact on climate change. Environmental quality has faced significant challenges in the last decades. Eco-environmental quality helps assess the condition of the ecological environment to support humans' civilization and development. By using emissions raster dataset, remote sensing images, and LULC data, this study explores the status of carbon emissions (CE), eco-environmental quality (RSEICs), and the dynamic relationship between both variables in Samarinda Metropolitan Area, Indonesia. This study uses the spatiotemporal approach to deepen the understanding of CE-RSEICs during 2000-2021. The methods include the analysis of CE and the principal component of RSEICs. To understand the CE-RSEICs spatial features, the directional distribution ellipse method is used. Also, this study performs CE-RSEICs coupling analysis and identifies its LULC type composition. The findings show that CE status is still on an increasing trend, concentrating in the eastern region and keeping expanding during the period. The location of the low-emission ellipse is in the southwest, while the high-emission ellipse is in the east and intersects with the core cities. The mean RSEICs value is between 0.2878 to 0.4223, which indicates that the eco-environmental quality is categorized as fairly poor to inferior. Greenness, wetness, and Csink have a positive impact on RSEICs. The very poor-class ellipse is located in the inland region, and the very good-class ellipse is in the coastal area. The CE-RSEICs coupling status shows that the majority of the area has a weaker coupling degree. However, the higher coupling degree is concentrated in the population center and built-up region, which is the settlement area. The dominance composition of settlement area in higher coupling degree shows that settlement area has an impact on increasing CE-RSEICs coupling degree. So, sustainable low carbon development in coastal metropolitan area must continue to be carried out by considering CE-RSEICs and its spatial aspects.

Coupling coordination of urbanization with ecological environment and influencing factors in Loess Plateau of China

The ecological damage caused by the accelerated urbanization process has continued to endanger the sustainable development of the Loess Plateau region, and the conflict between economic development and environmental protection has become increasingly critical. It is meaningful to explore the coupling coordination degree (CCD) between urbanization (UZ) and the ecological environment (EE) in the Loess Plateau and the mechanism of its influence to eliminate the locking of the rapid urbanization development paths in ecologically fragile regions, using panel data of 39 cities in the Loess Plateau region from 2010 to 2020. The empirical results have found that the level of UZ shows a fluctuating upward trend while the level of EE fluctuates and decreases. The synthesis CCD is at a barely coordinated level with an apparent upward trend, and the spatial characteristics are represented by "central depression," with low levels in the neighboring cities and high levels in the provincial capital cities. Regarding the driving factors, residents' living, industrial structure, and openness have a favorable impact on CCD, while enhancing the government's regulatory capacity has a negative blocking effect. These findings provide novel insights into the Loess Plateau's regional sustainable development.

Spatiotemporal evolution and multi-scale coupling effects of land-use carbon emissions and ecological environmental quality

The coupling relationship between land-use carbon emissions (LCE) and ecological environmental quality (EEQ) is critical for regional sustainable development. Rapid urbanization promotes a notable increase in LCE, which imparts significant stress on EEQ. This study used land use and cover change (LUCC) and Open-Data Inventory for Anthropogenic Carbon dioxide (ODIAC) data from the urban agglomeration in the middle reaches of the Yangtze River (UAMRYR) to evaluate LCE, applied a remote sensing ecological index (RSEI) model to calculate EEQ, and combined gravity and centroid movement trajectory models to analyze the spatiotemporal evolution characteristics of LCE and EEQ. Four-quadrant and coupling degree (CD) models were used to analyze the synergistic relationship and interaction intensity between LCE and EEQ based on three different scales of pixels, counties, and cities. The results show that: (1) LCE and EEQ exhibit clear spatial inequality distribution, and the total amount of LCE increased from 40.16 Mt. in 2000 to 131.99 Mt. in 2020; however, LCE has not yet reached peak carbon emissions. (2) From 2000 to 2020, cities with a strong correlation between LCE and EEQ showed an increasing trend, and the centroid of LCE moved sharply to Jiangxi during 2000-2005 and 2005-2010. (3) High-CD areas were primarily located in quadrant II, and low-CD areas in quadrant IV. The relationship between LCE and EEQ has improved over the past 21 years, and CD has been increasing. (4) The stability of the coupling results between LCE and EEQ was affected by different research scales; the larger the research scale is, the greater the change in the results. This study provides a scientific basis and practical scheme for LCE reduction, ecological environmental management, and regional sustainable development in the UAMRYR.

Monitoring grey water footprint and associated environmental controls in agricultural watershed

The grey water footprint (GWF) is an advanced index linking pollution load and water resources. However, the existing agriculture-related GWF was developed based on hydrological processes, which limits its role in watershed water pollution level (WPL) measurements. The main scope of this study is to calculate GWF and WPL based on runoff, total nitrogen (TN), and total phosphorus (TP) observations in the Hujiashan Watershed of China's Yangtze River Basin. Partial least squares structural equation modeling (PLS-SEM) was utilized to explore the impact pathways of environmental features on GWF and WPL. On this basis, propose measures for the management of this agricultural watershed. The results showed that the TN concentration had a V-shaped trend in 2008-2015, while the TP gradually decreased. The GWF calculations for the TN and TP were compatible with the temporal trends for the concentrations, which were higher in the wet season (0.45 m3/m2 for TN, 0.10 m3/m2 for TP) than in the dry season (0.11 m3/m2 for TN, 0.02 m3/m2 for TP) and increased from upstream to downstream. The WPLs of TN exceeded 2.0 in the midstream and downstream areas, whereas those for TP were inconspicuous. According to PLS-SEM, the GWF is primarily influenced by topographical variables and hydrological features, whereas the WPL is mainly controlled by hydrological features and landscape composition. Fertilizer reduction and efficiency measures should be implemented on farmland and appropriately reducing farming activities on slopes to relieve the GWF and WPL in the watershed.

Synergistic relationship and interact driving factors of pollution and carbon reduction in the Yangtze River Delta urban agglomeration, China

The urban agglomeration is the most concentrated region of economy, population, and industry. It is also the key area of carbon emissions (CE) and air pollution management. CE and air pollution have the possibility of collaborative governance due to the same root and the same source of them. To achieve the goal of sustainable development, it is important to study the coordinated relationship of CE and atmosphere pollutants in urban agglomerations. However, most researches have ignored the synergistic relationship between CE and air pollutants. Furthermore, there is limited current study on the driving factors of the synergistic relationship between air pollutants and CE. To fill these research gaps, we first explore the spatial-temporal evolvement law of CE and PM2.5 utilizing satellite remote sensing data sets. Secondly, we analyze the synergistic relationship of CE and PM2.5 in the Yangtze River Delta (YRD) urban agglomeration using the coupling coordination degree (CCD) model from 2000 to 2020. At last, we further study the influencing factors of the synergistic relationship of CE and PM2.5 based on the geo-detector model. The findings display that (1) in 2020, the total CE in the YRD urban agglomeration is 2.24 billion tons, accounting for 22.5% of China, but its growth rate has gradually dropped to 7.25%. Besides, the PM2.5 concentration shows a waving upward-downward tendency. In 2020, the range of higher PM2.5 regions significantly decreased, and air quality gradually improved. (2) The CCD of PM2.5 and CE is at the coordination level in general (CCD > 0.6) between 2000 and 2020, which can realize the coordinated governance of pollution and carbon reduction. (3) Digital elevation model (DEM), topographic relief (RDLS), and population density have a higher degree of influence on the synergistic relationship between CE and PM2.5. Besides, the interaction of topographic and socio-economic factors is the main driving factor between the two. This paper can provide a referral for decision-makers to synergistically make plans for pollution and carbon reduction and facilitate the sustainable development of urban agglomerations.

Does green location-oriented policy enhance ecological resources and reduce air pollution? Empirical analysis from counties in China

Green location-oriented policy plays a vital role in improving the ecological security. Using the multi-phase difference-in-difference (DID) method, this study evaluates the impact of national key ecological functional areas (NKEFA) on ecological resources and environmental pollution. There are several important findings. Firstly, NKEFA effectively enhances ecological resources and reduces air pollution, the policy effect only manifests after two years of implementation. Secondly, NKEFA has indirectly improved air quality by promoting technological innovation, advanced industrial structure, and regional ecological resource quality. Moreover, the relationship between NKEFA and ecological resources is negatively regulated by industrialization and economic agglomeration, while the relationship between NKEFA and air pollution is positively regulated by them. Thirdly, NKEFA has the strongest impact on enhancing ecological resources in the eastern region, and it is more effective in reducing air pollution in the central and eastern regions compared to the western regions. Furthermore, the NKEFA demonstrates the greatest effectiveness in promoting ecological resources and reducing air pollution in water and soil conservation areas. However, there is a spatial spillover effect, which suggests that this policy has some negative impacts on the surrounding counties' ecological environment.

Identifying the coupling coordination relationship between urbanization and forest ecological security and its impact mechanism: Case study of the Yangtze River Economic Belt, China

Boosting the coordination and symbiosis of urbanization and forest ecological security is notably critical for promoting regional green and sustainable development and achieving emission peak and carbon neutrality goals. However, there was still a lack of in-depth analysis of the coupling coordination relationship between urbanization and forest ecological security and its impact mechanism. On the basis of the data from 844 counties in the Yangtze River Economic Belt, this paper explored the spatial differences and influencing factors of the coupling coordination degree of urbanization and forest ecological security. The results manifested that: i) There were apparent spatial disparities in the urbanization index, forest ecological security index, comprehensive index, coupling degree and coupling coordination degree of the Yangtze River Economic Belt. Among them, the spatial pattern of coupling coordination degree had a strong consistency with urbanization index, that is, areas with higher urbanization index also had higher coupling coordination degree. ii) Based on coupling feature identification, it was found that 249 'problem areas' were mainly located in Yunnan Province, southeastern Guizhou Province, central Anhui Province, and central and eastern Jiangsu Province. The main factor for the formation was due to the lag of urbanization in coordinated development. iii) Among the socioeconomic indicators, population structure (0.136), per capita year-end financial institutions loan balance (0.409) and per capita fixed asset investment (0.202) all had a positive impact on coupling coordination degree, while location conditions (-0.126) had a negative impact. Among the natural indicators, soil organic matter (-0.212) and temperature (-0.094) had a negative impact on coupling coordination degree. iv) During the process of coordinated development, it was necessary to increase financial investment and financial support, actively formulate policies to attract talents, enhance the education and publicity of ecological civilization, and develop a green circular economy. The above measures can promote the harmonious development of urbanization and forest ecological security in the Yangtze River Economic Belt.