Exploring the causal relationships and pathways between ecological environmental quality and influencing Factors: A comprehensive analysis

The temporal and spatial changes of the ecological environment quality of the urban agglomeration on the northern slope of Tianshan Mountain and the influencing factors

The Lhasa to Nyingchi Expressway in Xizang made efforts to protect the ecological environment during its construction, but it still caused varying degrees of damage to the fragile ecosystems along the route. Accurately assessing the process of change in the ecological environment quality in this region holds significant research value. This study selected the Linzhi-to-Gongbo’gyamda section of the Lhasa-to-Nyingchi Expressway as the research area. Firstly, based on the remote sensing ecological index (RSEI), this study constructed an ecological environmental quality evaluation system for the Xizang region. Subsequently, using the Google Earth Engine (GEE) platform, sub-indicators were extracted, and the combination weighting method of game theory was employed to determine indicator weights. This process resulted in the calculation of the MRSEI for the study area from 2012 to 2020. Finally, by utilizing the spatial distribution of the MRSEI, monitoring the level of MRSEI changes, and employing the transition matrix, this study analyzed the changing trend of the ecological environmental quality from 2012 to 2020. The results indicate that the MRSEI are 0.5885, 0.5951, 0.5296, 0.6202, 0.59, 0.5777, 0.5898, 0.5703, and 0.5987, showing a gradual increasing trend with an initial decrease followed by an ascent. This trend is mainly attributed to concentrated road construction and subsequent ecological restoration, leading to an improvement in the restoration effect. Simultaneously, the ecological environmental quality remains relatively stable, with 69.5% of the region showing no change, and the remaining 30.5% experiencing improvement exceeding degradation. Specifically, there were significant improvements in the land with ecological quality levels categorized as poor, fair, moderate, and good. The types of degradation primarily involved lands originally classified as excellent and good degrading to good and moderate levels, respectively. The above results serve as a theoretical reference for the ecological restoration project of the Lhasa-to-Nyingchi Expressway.

Abstract. In order to monitor the change of regional ecological environment quality, this paper use MODIS and DMSP / OLS remote sensing data, from the production capacity, external disturbance changes and human socio-economic development of the three main factors affecting the quality of ecosystems, select the net primary productivity, vegetation index and light index, using the principal component analysis method to automatically determine the weight coefficient, construction of the formation of enhanced remote sensing ecological index, and the ecological environment quality of Hainan Island from 2001 to 2013 was monitored and analyzed. The enhanced remote sensing ecological index combines the effects of the natural environment and human activities on ecosystems, and according to the contribution of each principal component automatically determine the weight coefficient, avoid the design of the weight of the parameters caused by the calculation of the human error, which provides a new method for the operational operation of regional macro ecological environment quality monitoring. During the period from 2001 to 2013, the ecological environment quality of Hainan Island showed the characteristics of decend first and then rise, the ecological environment in 2005 was affected by severe natural disasters, and the quality of ecological environment dropped sharply. Compared with 2001, in 2013 about 20000 square kilometers regional ecological environmental quality has improved, about 8760 square kilometers regional ecological environment quality is relatively stable, about 5272 square kilometers regional ecological environment quality has decreased. On the whole, the quality of ecological environment in the study area is good, the frequent occurrence of natural disasters, on the quality of the ecological environment to a certain extent.

Spatiotemporal evolution of ecological environmental quality and its dynamic relationships with landscape pattern in the Zhengzhou Metropolitan Area: A perspective based on nonlinear effects and spatiotemporal heterogeneity

The Kundulun River Basin is the most prominent branch of the Yellow River system within the jurisdiction of Baotou City. As an important water source and ecological barrier, its ecological quality is directly related to the ecological security and sustainable development of the surrounding areas. This study selected the Kundulun River Basin in Baotou City as the research area. On the basis of collecting relevant information, a field investigation was conducted on the ecological and geological conditions of the atmospheric surface subsurface Earth system, using the watershed as the survey scope and water as the carrier for the transfer and conversion of materials and energy in the watershed. This study selected the main factors that affect the ecological geological quality of the watershed and established an evaluation model using the analytic hierarchy process, the coefficient of variation method, and the comprehensive analysis method. We have established an ecological geological quality evaluation index system for the Kundulun River Basin. We conducted quantitative evaluation and comprehensive analysis of regional ecological and geological environment quality. The results indicate that ecological environment indicators contribute the most to the ecological quality of the study area, while the impact of human activities on ecological quality is relatively small. From the perspective of evaluation indicators, grassland has the highest weight, followed by precipitation, groundwater depth, forest land, and cultivated land. Approximately 30.26% of the land in the research area is in a state of high or relatively high ecological and geological–environmental quality risk. It can be seen that the overall quality of the ecological geological environment is not optimistic and needs further protection.

With the ecological environment problems being increasingly prominent and globalized, more and more attention is paid to environmental protection. Remote sensing technology is important in monitoring and evaluating ecological environment. In this study, based on the Landsat image data of 1992, 2000, 2008 and 2017, the remote sensing ecological index (RSEI) was constructed to monitor and evaluate the quality of ecological environment in Hangjin Banner, Inner Mongolia, aiming to provide a theoretical basis for local ecological environment protection. The results showed that from 1992 to 2017, the quality of ecological environment in Hangjin Banner was generally poor, with RESI grades of poor and inferior. The mean value of RESI increased from 0.31 (1992) to 0.37 (2008) and then decreased to 0.30 (2017). During the period, the change range was mainly from one grade to the next. In terms of spatial distribution, the regions with poor ecological environment quality were mainly in the desert plains of the central and western regions, that with good ecological quality mainly along the Yellow River and in the southeast, and that with large fluctuation of ecological quality grade mainly in the desert edge along the Yellow River and in the hilly and gully regions in the east. During the research period, the center of gravity of each ecological grade in Hangjin Banner substantially shifted, with spatiotemporal fluctuations. Our results suggest that ecological environment of Hangjin Banner was fragile and unstable. Ecological construction can promote the quality of ecological environment, but resources and land use should also be reasonably allocated.

Monitoring and assessing spatiotemporal changes and driving factors of ecological environment quality in the middle Yellow River Basin (MYRB) is significant for ecological environment protection, management, and high-quality development. We reconstructed data from 1986‒2023 Landsat series images using the harmonic analysis of time series (HANTS) algorithm on the Google Earth Engine platform to optimize the remote-sensing ecological index (RSEI) calculation process, and analyzed the trends and sustainability of ecological environment quality changes. The HANTS algorithm reduced dispersion and anomalies, filled in missing images, and enhanced the Landsat series image quality. The RSEI accurately reflected the ecological environment quality from 1986‒2023 in the MYRB, reducing the "pseudo-variation" conclusion of multi-year evaluations, and enhancing the stability of regional ecological environment quality assessments. Ecological environment quality in the MYRB generally showed an improving trend from 1986‒2023, with significant improvement covering 71.6% of the area; however, the change in ecological environment quality showed weak sustainability. The results reflected the positive effects of ecological restoration and the negative impact of urban construction. The optimized RSEI effectively reflected the ecological environment quality of the MYRB, improved the long-term RSEI stability, and satisfied the requirements of large-scale and long-term ecological environment quality monitoring.

Climate change and anthropogenic activities pose a formidable challenge to regional ecological systems， necessitating robust research frameworks to assess ecological environment quality. The dynamic， quantitative evaluation of such quality serves as a cornerstone for strategizing ecological protection measures and fostering ecological civilization. Leveraging MODIS data spanning from 2001 to 2020， this study harnesses the power of the Google Earth Engine （GEE） platform and the remote sensing ecological index （RSEI） as a pivotal evaluation tool to conduct a comprehensive appraisal of the ecological health of the southern slope of the Qilian Mountains. Employing Sen's trend analysis and the Mann-Kendall （M-K） test， we delineate the spatial evolution patterns of the RSEI， offering insights into its temporal dynamics. Furthermore， by integrating geological information mapping with Pearson correlation analysis， we delve into the intricate interplay between natural environmental factors and human activities that shape RSEI variations. Our findings revealed several salient points： Firstly， the ecological quality of the southern slope of the Qilian Mountains exhibited pronounced spatial heterogeneity， with the vicinities of the Datong， Heihe， Beida， and Babao River basins boasting exceptional ecological quality， in contrast to the relatively degraded conditions in higher-elevation areas. Temporally， from 2001 to 2020， the RSEI index fluctuated within a range of 0.62 to 0.70， signifying an overall enhancement in ecological environment quality， a testament to the vigorous implementation of ecological restoration projects in recent years. The average annual RSEI value stood at 0.66， indicative of stability amidst modest fluctuations， though peripheral regions experienced notable RSEI volatility due to climatic shifts. Encouragingly， over 80% of the southern slope experienced ecological improvement， with a mere 11% experiencing slight degradation， suggesting a promising trajectory for future ecological enhancement. However， caution must be exercised against the risk of unsustainable improvement. Temperature， precipitation， and human interventions all contributed to RSEI variations， with temperature exerting a more pronounced influence than precipitation. Notably， human activities correlated positively with RSEI， underscoring the significance of human stewardship in ecological improvement. This research fills a critical gap in the long-term， dynamic monitoring of the ecological environment on the southern slope of the Qilian Mountains， providing a robust foundation for targeted ecological governance and fostering green development initiatives in this vital region.

Clarifying the impacts of urban land expansion on changes in the quality of the ecological environment in the Beijing-Tianjin-Hebei （BTH） urban agglomeration is of great significance for the high-quality development of the BTH urban agglomeration and the construction of ecological civilization. The urban expansion rate， urban expansion intensity， and landscape pattern index were introduced to analyze the urban expansion pattern of the BTH urban agglomeration from 2000 to 2020， the integrated remote sensing eco-environment index （IRSEI） was constructed based on the Google Earth Engine （GEE） platform to evaluate the regional eco-environmental change status， and the impact of the evolution of urban expansion pattern on the change of eco-environmental quality was investigated using a geographically and temporally weighted regression model （GTWR）. The study produced several interesting results： ① The overall expansion rate of urban land in the BTH urban agglomeration from 2000 to 2020 was 217.22 km2·a-1， and the expansion rate from 2000 to 2010 was faster than the rate from 2010 to 2020. Among regions， the urban expansion rate was slower in the northwestern mountains and higher in the southeastern plains. The overall expansion intensity of the BTH urban agglomeration during the study period was 6.14%. Areas with high-speed expansion， rapid expansion， and medium-speed expansion were mainly concentrated in the southeastern plains， and areas with low-speed expansion and slow expansion were mainly located in the northwestern part of the study area. During the study period， the number of urban agglomerations in BTH， the density of patches， and the landscape shape index showed increasing trends， the maximum patch index showed a decreasing trend， and the fragmentation of urban land was increasing. ② During the period from 2000 to 2020， the IRSEI of the BTH urban agglomeration as a whole showed an upward trend. In 2020， the IRSEI had increased by 6.13% compared with the early stage of the study， and the ecological environment quality of the Yanshan Mountain area in the north and the Taihang Mountain area in the west was higher， while that of the Bashang Plateau area and the southeastern plains area was poorer. During the study period， the ecological environment quality decreased mainly in the peripheral area along the Bohai Sea and the Southeast Plain area， especially in and around the urban centers， while the ecological environment quality increased mainly in the western Taihang Mountain area and the northern Yanshan Mountain area. ③ The degree of influence of urban expansion on the changes of ecological environment quality revealed obvious spatial differentiation， and the regression coefficient of landscape shape index was negative in most counties and regions， which is the main reason for the changes of ecological environment quality. Urban expansion has mainly negative impacts on the ecological environment quality in the region， and reasonable development policies should be formulated to harmonize urban development with ecological environment protection.

Economic globalization and rapid urbanization have affected ecological environments in global regions to different degrees. Timely, objective and quantitative evaluations of the spatiotemporal variations in regional ecological environmental quality are the key to environmental protection and decision making. The spatial distributions of ecological environment quality levels along the Jakarta–Bandung high-speed railway from 2000 to 2020 were obtained based on Google Earth Engine and the Remote Sensing Ecological Index (RSEI). Then, the Theil–Sen median and Mann-Kendall methods were used to assess the temporal RSEI trend; the spatial autocorrelation evaluation index was used to evaluate RSEI clustering on a spatial scale. The results show that the overall ecological environmental quality from 2000 to 2020 was moderate, with temporally fluctuating changes and very significant spatial clustering. Approximately 20% of the area showed very strong changes (improvement or degradation). Areas with relatively better ecological quality were located mainly in relatively high-elevation and high-vegetation-coverage regions, while areas with poorer ecological quality were located mainly in the four major cities, including Jakarta, with concentrated populations and developed economies. The research results provide local governments with scientific suggestions regarding the synergistic development of high-speed railway construction and ecological environmental protection.

As an important platform for participating in international competition and cooperation, supporting economic growth and promoting coordinated regional development, urban agglomeration plays an important role in China’s economic, social and urbanization development. At this time, the Guanzhong Plain urban agglomeration (GZPUA), as the second largest urban agglomeration in western China, has a moderate population density. The high demand and high input of resources for population growth make the regional ecological destruction and environmental pollution more prominent. Therefore, it is of great practical significance to study the coordinated development of urbanization and ecological environment in GZPUA. By using the panel data of the GZPUA of China between 2008 and 2017, this study constructed evaluation index system of new-type urbanization and ecological environment quality and calculated the weights of the indices within the evaluation system via the improved entropy weight method, finally determined the new-type urbanization and ecological environment quality of each city. Then the coupling coordination degree model was used to analyze the coupling coordination relationship between two systems of GZPUA and their coupling stages and levels. In addition, the driving mechanism of their coordination degree was explored by using geographic detector method. The results show that: 1) The GZPUA new-type urbanization quality is characterized by both slow growth except Xi’an by a rapid increase. The ecological environment quality is characterized by both slow growth and fluctuations, except Qingyang by a decrease. There are spatial differences between the quality of new-type urbanization and the quality of ecological environment. 2) The 11 cities can be divided into high-high type (Xi’an), high-low type (Xianyang, Yuncheng, Linfen), low-low type (Pingliang, Weinan), and low-high type (Shangluo, Tianshui, Qingyang), different types should take different development paths. 3) The coordination degree between urbanization and ecological environment quality in GZPUA showed an upward trend, and formed a spatial distribution pattern with Xi’an as the core and decreasing to the outer circle cities, with regional differences. 4) The coordinated development of new-type urbanization and ecological environment is a process in which various driving factors act on different driving forces. These driving forces can be summarized as market driving force, endogenous driving force, outward driving force and administrative driving force. Based on the current situation of coordinated development of new-type urbanization and ecological environment in the GZPUA, it is recommended to promote the coordinated development of urbanization and ecological environment according to local conditions, strengthen the urbanization market mechanism, and optimize the industrial layout. Further, guide the flow of various factors across regions, strengthen technological innovation on the basis of breaking regional divisions, narrow the gap between urban and rural areas, establish the concept of coordinated development, and give play to the government’s “visible hand” role.

With rapid urbanization and increasingly prominent environmental issues, objective evaluation of the quality of the ecological environment is crucial for environmental protection and sustainable development. Most remote sensing ecological indices (RSEI) used for ecological environmental quality evaluation include only four indicators (greenness, humidity, heat, and dryness), and many studies have ignored the impact of air quality on urban ecological environmental quality in arid areas. This study used the urban agglomeration on the northern slope of the Tianshan Mountains (UANSTM), China, as the research area based on the Google Earth Engine platform via Landsat remote sensing images and NPP/VIIRS data to establish a new remote sensing ecological index (RSEInew) and compounded night light index of urbanization level. The coupling coordination degree model was used to quantitatively analyze the characteristics of the coordinated development of the ecological environment and urbanization in UANSTM and major cities from 2015 to 2020. The results showed that: (1) compared to RSEI, RSEInew is more suitable for assessing the ecological quality of arid zones because it accounts for air quality; (2) the RSEInew value for the eco-environmental quality of UANSTM from 2015 to 2020 improved and then deteriorated with an overall declining trend. The variation in the RSEInew rating was between “strongly bad” and “neutral,” and there were differences in the quality of the ecological environments among cities; (3) the level of urbanization in the economic zone of UANSTM from 2015 to 2020 increased significantly, and the degree of coordination between urbanization and ecological environmental quality coupling steadily increased but remained moderately imbalanced. The results of this study provide a scientific reference for the economic development and ecological environmental protection of the study area.

The construction of rural tourism destroys the natural ecological environment, and tourists in tourism areas also produce a lot of domestic waste for the ecological environment. Therefore, this study established the hierarchical analysis method-AHP to explore the coupling relationship between the construction of rural tourism area and ecological environment, and also evaluated the influence of the factors of rural tourism area on the quality of rural ecological environment. The results showed that tourism areas could lead to an increase in nitrogen organic matter in ecological water and greenhouse gas. The increase in tourists also led to a significant decrease in water and air quality. The number of air quality monitoring stations helps to improve the ecological environment and construction materials in rural tourism areas have an impact on ecological quality. Therefore, a certain number of environmental monitoring stations can control the number of tourists and the area of tourist areas, and choose environmentally friendly construction materials to improve the quality of ecological environment.

With the rapid development of social economy, the ecological environment problems caused by the change of wetland land use have been widely concerned. This paper takes the Caohai National Nature Reserve (CNNR) of China as the research object on the basis of referring to previous research results. Firstly, the remote sensing data was employed to examine the spatio-temporal evolution process of the CNNR from three aspects: land use structure change, land use dynamic degree and land use space change. Then the change of ecological environment quality was studied from the greenness, the wetness, the dryness and the heat. Based on the spatiotemporal changes of land use types and ecological environment quality in the CNNR from 2000 to 2020, a comprehensive index, the remote sensing ecological index (RSEI), was constructed to analyze the ecological environmental effects of land use changes. The results indicate that the land use changes in the CNNR went through two major periods: first, a period of rapid decline in cultivated land, and second, a period of sharp increase in constructed land. During the period of rapid decline in cultivated land, the ecological environment quality in the study area showed an upward trend. However, during the period of increased constructed land, the ecological environment quality gradually stabilized. This study provides a basis for the coordinated development of the ecological environment and social economy in the CNNR area.

Under the short-term economic development goal, the excessive exploitation of natural resources and the destruction of the ecological environment make the ecological environment of Huaibei cities increasingly fragile. This study constructed the Remote Sensing Ecological Index (RSEI) to evaluate the ecological environment change trend and its driving factors in Huaibei City from 2000 to 2020. The barycenter migration model was used to determine the RSEI spatial change trend, and the geographic detector was used to analyze the influencing factors of the RSEI value change. The results showed that: (1) the average RSEI value of Huaibei City generally fluctuates within the range of good and excellent grades. (2) The migration direction of the barycenter of RSEI is similar when the level of RSEI improves or decreases from 2000 to 2020, and the barycenter migration is most severe from 2005 to 2015. (3) The driving factors of RSEI change were population density (0.47) > land use (0.24) > slope (0.14) > precipitation (0.08) > temperature (0.04) > altitude (0.03). All the factors had interaction effects on the RSEI, mainly with nonlinear enhancement. (4) From 2000 to 2010, urban construction encroached on all kinds of land, which was the direct reason for the decline in ecological environment quality. From 2010 to 2020, the surge of water and meadow areas improved the ecological environment quality of Huaibei city. Therefore, reducing the expansion of artificial land, returning farmland to forests and meadows, wetland park construction, and other ecological protection measures are the keys to ensuring the sustainable development of regional social and economic development. This study can provide a reference and scientific basis for sustainable development strategy and ecological protection planning to improve the ecological environment quality of Huaibei City.