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Analyzing land use changes (LUC) in both past and future scenarios is critical to optimize local ecology and formulate policies for sustainable development. We analyzed LUC characteristics in Huaibei City, China from 1985 to 2020, and used the CLUE-S and PLUS models to simulate LU in 2020. Then, we compared the accuracy of the simulation phase and chose the PLUS model to project LU under four scenarios in 2025. The results showed the following: (1) Farmland and grassland areas decreased from 1985 to 2020, while forestland, water, and construction land increased. (2) The LU types in the region are explained well by the driving factors, with all receiver operation characteristic (ROC) values greater than 0.8. (3) The kappa indices for CLUE-S and PLUS analog modeling were 0.727 and 0.759, respectively, with figure of merit (FOM) values of 0.109 and 0.201. (4) Under the farmland and ecological protection scenario (FEP), farmland and forestland areas are protected, increasing by 1727.91 hm2 and 86.22 hm2, respectively, while construction land decreases by 2001.96 hm2. These results confirm that PLUS is significantly better than the CLUE-S model in modeling forestland and water, and slightly better than the CLUE-S model in modeling the rest of the LU type. Urban sustainability is strong in the scenario FEP.

Regional logistic networks and linking urban clusters to boost high quality economic development are both key topics in sustainable development in China. In recent years, China has highlighted the significance of the logistics industry and urban cluster development, attaching practical importance to the connections between these two topics from a spatial perspective. This paper aims to discuss how regional logistic networks linking urban clusters improve economic development. This study constructs a logistic evaluation indicator system based on the multi-indicator data of 11 cities in the Guangdong-Hong Kong-Macao Greater Bay Area in 2020. This research employs the entropy-weighted-TOPSIS method to measure and rank the comprehensive logistics quality of each city in the economically linked logistic network of the Guangdong-Hong Kong-Macao Greater Bay Area. This study applies the modified gravity model to explore the logistics linkage and logistic network characteristics of each city in the Guangdong-Hong Kong-Macao Greater Bay Area. Finally, this research analyzes how the agglomeration ability of the central cities in the Guangdong-Hong Kong-Macao Greater Bay Area affects other cities from a spatial perspective. Furthermore, this spatial perspective investigates the agglomeration effect of the economic linkage logistic network through the social network analysis method. The results have the following three implications. (1) The logistic network has a high density, a stable overall structure with a strong agglomeration effect, and there is an increasingly mature logistic network development in the Guangdong-Hong Kong-Macao Greater Bay Area in the Bay Area. (2) Agglomeration is significant in the central cities of the Guangdong-Hong Kong-Macao Greater Bay Area including Hong Kong, Shenzhen, Guangzhou, and Macao. Nonetheless, insufficient peripheral cities have been cultivated. Therefore, the government should focus on strengthening the balance of urban development in the bay area and improving the logistics access among cities to break through the barriers of regional synergistic development. (3) The economic development of cities is highly correlated with the level of logistics links. Additionally, the economy is the cornerstone to promoting the high-quality development of the logistics industry. Moreover, the economy and logistics are inseparable, mutually promoted, and developed together.

Soil organic matter (SOM) is a key index of soil fertility. Visible and near-infrared (VNIR, 350–2500 nm) reflectance spectroscopy is an effective method for modeling SOM content. Characteristic wavelength screening and spectral transformation may improve the performance of SOM prediction. This study aimed to explore the optimal combination of characteristic wavelength selection and spectral transformation for hyperspectral modeling of SOM. A total of 219 topsoil (0–20 cm) samples were collected from two soil types in the East China. VNIR reflectance spectra were measured in the laboratory. Firstly, after spectral transformation (inverse-log reflectance (LR), continuum removal (CR) and first-order derivative reflectance (FDR)) of VNIR spectra, characteristic wavelengths were selected by competitive adaptive reweighted sampling (CARS) and uninformative variables elimination (UVE) algorithms. Secondly, the SOM prediction models were constructed based on the partial least squares regression (PLSR), random forest (RF) and support vector regression (SVR) methods using the full spectra and selected wavelengths, respectively. Finally, optimal SOM prediction models were selected for two soil types. The results were as follows: (1) The CARS algorithm screened 40–125 characteristic wavelengths from the full spectra. The UVE algorithm screened 105–884 characteristic wavelengths. (2) For two soil types and full spectra, CARS and UVE improved the SOM modeling precision based on the PLSR and SVR methods. The coefficient of determination (R2) value in the validation of the CARS-PLSR (PLSR model combined with CARS) and CARS-SVR (SVR model combined CARS) models ranged from 0.69 to 0.95, and the relative percent deviation (RPD) value ranged from 1.74 to 4.31. Lin’s concordance correlation coefficient (LCCC) values ranged from 0.83 to 0.97. The UVE-PLSR and UVE-SVR models showed moderate precision. (3) The PLSR and SVR modeling accuracies of Paddy soil were better than those for Shajiang black soil. RF models performed worse for both soil types, with the R2 values of validation ranging from 0.22 to 0.68 and RPD values ranging from 1.01 to 1.60. (4) For Paddy soil, the optimal SOM prediction models (highest R2 and RPD, lowest root mean square error (RMSE)) were CR-CARS-PLSR (R2 and RMSE: 0.97 and 1.21 g/kg in calibration sets, 0.95 and 1.72 g/kg in validation sets, RPD: 4.31) and CR-CARS-SVR (R2 and RMSE: 0.98 and 1.04 g/kg in calibration sets, 0.91 and 2.24 g/kg in validation sets, RPD: 3.37). For Shajiang black soil, the optimal SOM prediction models were LR-CARS-PLSR (R2 and RMSE: 0.95 and 0.93 g/kg in calibration sets, 0.86 and 1.44 g/kg in validation sets, RPD: 2.62) and FDR-CARS-SVR (R2 and RMSE: 0.99 and 0.45 g/kg in calibration sets, 0.83 and 1.58 g/kg in validation sets, RPD: 2.38). The results suggested that the CARS algorithm combined CR and FDR can significantly improve the modeling accuracy of SOM content.

Topographic relief is a key factor limiting population distribution and economic development in mountainous areas, especially in the transition zone from mountains to plains. Taking the southern Anhui mountainous area as an example, based on the digital elevation model (DEM) with a resolution of 30 m, we used ‘quadratic’ mean change-point analysis to calculate the optimal statistical unit, and then extracted the topographic relief. Taking the county as the unit of analysis, two indicators of population density and economic density were selected. Spatial statistics and correlation analysis were used to quantitatively analyze the impact of topographic relief on population and economy. Finally, the impact of slope and elevation was analyzed. The following results were obtained. (1) The topography of the study area was dominated by medium relief (200–500 m), followed by small relief (70–200 m), flat (0–30 m), and slight relief (30–70 m), and a small proportion of large relief (≥500 m). (2) The impact of topographic relief on population and economy was slightly stronger than that of slope and elevation. The impact on population distribution was stronger than that on economic development. The impact on primary industry was stronger than that on secondary and tertiary industries. (3) In the southern Anhui mountainous area, 72.35% of the population and 76.72% of GDP were distributed in the area with a topographic relief of 155 m or less, while the land area only accounted for 43.93%. The area with a topographic relief greater than 245 m accounted for 28.76%, but only 10.69% of the population, and only 8.34% of GDP. The population distribution and economic development were obviously concentrated in the low topographic relief area. However, the characteristics of high topographic relief not only hindered the agricultural mechanization and limited the development of the primary industry, but also had a significant impact on infrastructure development, investment, and industrial layout, thus weakening regional economic advantages. In the future, the economic level of these areas needs to be improved.

The provision of ecosystem services from multifunctional landscapes has contributed to human well-being. However, a general tendency exists to consider only marketed ecosystem services and to ignore non-marketed services, which has become more common when evaluating multiple-ecosystem services at the local level. In this study, we present an integrative index of multiple-ecosystem services ( IMES ) that avoids this tendency. Our main objective is to evaluate how socioeconomic factors interact with the spatial differences between the supply of and demand for multiple-ecosystem services. GlobCover data and a modified ecosystem service “matrix” are used to quantify and map ecosystem service supply and demand at the municipality level in the Yangtze River Basin, China. We used multiple regression analysis to detect relationships between ecosystem services and socioeconomic factors in municipalities to identify the main drivers of change in the supply of and demand for multiple-ecosystem services at the local level, respectively. The results revealed that 111 municipalities in the Yangtze River Basin (84.7% of the area) had an oversupply of multiple-ecosystem services; these municipalities were primarily situated in the western part of the upper reach and the southeast parts of the middle reach. Undersupplied areas were mainly situated in densely populated municipalities in the northern part of the lower reach and in agricultural municipalities in the northeastern part of the middle reach. The driving factors of changes in multiple-ecosystem services are significantly different not only in terms of the supply, demand and balance between the two but also among the three reaches. These differences in the driving factors among the three reaches can produce incorrect conclusions if an entire basin is considered, particularly for large basins. This information may be of interest to policymakers. The first principal component for the supply of and demand for multiple-ecosystem services exhibits a good correlation with the IMES in the Yangtze River Basin. Additionally, the integrative index of multiple-ecosystem services (including IMES s and IMES d ) in the study area is relatively reliable according to the sensitivity analysis. Therefore, IMES is an effective tool for aggregating the value of multiple-ecosystem services at local scales. This tool can be used to identify the drivers of changes in multiple-ecosystem services based on the relationships between IMES and socioeconomic factors at the municipality scale. IMES should be useful for policymakers and stakeholders because it can provide important information for local decision-making.

In recent years, air pollution situation becomes more severe and has seriously threatened sustainable economic development and public health in China. Combining the improved slacks-based measure (SBM) model, global Malmquist-Luenberger (GML) productivity index and panel Tobit model, this paper investigates the regional differences, dynamic evolution and influencing factors of China’s provincial air pollution emission efficiency over the period 2006–2015 under the total-factor framework. Our results show that: (1) China’s total-factor air pollution emission efficiency is relatively low and exhibits significant regional differences; (2) technological progress is the main contributor to ameliorate China’s provincial total-factor air pollution emission efficiency; (3) the total-factor air pollution emission efficiency gap between the higher- and the lower-efficient provinces will probably widen in the future; (4) China’s provincial total-factor air pollution emission efficiency is significantly positive related to the level of economic development, industrial structure optimization, technological innovation and foreign direct investment (FDI), is significantly negative related to the energy consumption structure. The above results indicate that China has made remarkable achievements in improving regional total-factor air pollution emission efficiency. However, there is considerable potential for further improvement. Policy options for China’s regional total-factor air pollution emission efficiency improvement include but not limited to optimizing industrial and energy consumption structure, promoting environmental technology innovation, strengthening cooperation and exchange between different regions, deepening the reform of energy market and energy pricing mechanism, actively introducing foreign investment, and further improving environmental regulation level.

Land use changes can isolate habitat patches, thereby aggravating the fragmentation of these units and altering natural ecological processes. Thus, it is necessary to analyze the responses of ecosystem services to changes in land use over time. Polders, a typical floodplain landscape in the Chaohu Lake Basin, were selected as the study area to evaluate how ecosystem services respond to changes in both land use and patch size over time. Multiple approaches, including remote sensing, geographical information system and correspondence analysis, were used. The results showed that the total ecosystem services were increased from 9.97 × 108 to 1.02 × 109 Yuan for all polders. Based on a correspondence analysis, recreation and culture, water supply and waste treatment are the ecosystem services that depend on water bodies, whereas six other types of ecosystem services (biodiversity protection, climate regulation, food production, raw material, soil formation and protection and gas regulation) depend on soil. Therefore, there are trade-offs between the ecosystem services provided by farmlands and those provided by water bodies, between supporting and provisioning services and cultural services in the polders, and between provisioning services and most regulating services. Furthermore, trade-offs and synergies were detected among regulating services. In this study, the relationships between patch sizes and ecosystem services were significantly changed during the 1985–2007 period, particularly from 2000 to 2007. The area variation of special land use can drive changes in these relationships. Notably, correspondence analysis can be used as a method to analyze synergies and trade-offs among multiple ecosystem services.