Spatial-Temporal Pattern and Evolution Trend of the Cultivated Land Use Eco-Efficiency in the National Pilot Zone for Ecological Conservation in China

Spatiotemporal differences, dynamic evolution and trend of cultivated land use efficiency: Based on three food functional areas

China's agricultural development has entered a period of transition, and improving the cultivated land use efficiency (CLUE) is of great significance for guaranteeing national food security. Based on the province panel data in China from 2000 to 2021, this research calculates the cultivated land use efficiency, and uses the Dagum-Gini coefficient, Kernel density estimation, and Markov chain to conduct an in-depth analysis of CLUE's regional variations and distribution dynamics in three food functional areas (TFA) of China. The study results showed that the trend of CLUE was characterized by "increasing levels and decreasing absolute differences," not only in the whole country but also in the TFA. The inter-regional variation among TFA is gradually narrowing, and the cross-group degree of inter-regional variation is on the rise. The upward probability of CLUE was more effective than the probability of a transitionary change, and the mutual influence of CLUE between neighboring cities would lead to spatial convergence in the level of CLUE in the long term. Therefore, improving CLUE in China's TFA should not only grasp the regional differences in CLUE but also actively utilize the spatial spillover effects among functional regions to realize the cross-regional synergistic development of cropland utilization efficiency in China.

The impact of clean energy demonstration province policies on carbon intensity in Chinese counties based on the multi-phase PSM-DID method

Based on China's empirical data from 2000 to 2020 of 1875 county-level administrative units, combined with the multi-phase by the propensity score matching and difference-in-difference (PSM-DID) model, this paper studies the impact of clean energy demonstration province policies on the carbon intensity of pilot counties, and its further impact on carbon emissions and economic development level. The results showed that 1. from a county-level perspective, although the economic development level of the pilot areas of clean energy demonstration provinces has improved as the carbon emissions have also increased, what is more, the carbon intensity has also significantly improved in this process; 2. there is no time lag in the impact of policies on the carbon intensity of counties, and the impact effects gradually increase over time along with strong regional heterogeneity; 3. the clean energy demonstration policy has weakened the technological level of the county and reduced the proportion of industrial-added value to GDP, thereby increasing the carbon intensity of the county through these intermediaries.

Study on eco-efficiency of cultivated land utilization based on the improvement of ecosystem services and emergy analysis

Cultivated land is the result of the cooperation between humans and nature. The utilization of cultivated land hopes to realize a "win-win" situation of food production and ecological protection to promote sustainable development. Previous studies on the eco-efficiency of agro-ecosystem mainly considered material input, agricultural product output and environmental pollution, and did not systematically include the natural input and ecological product output, which had limitations on the study of sustainable development of cultivated land utilization. Therefore, this study initially used emergy analysis and ecosystem service assessment methods to include the natural input and ecosystem service output of cultivated land into the assessment framework of eco-efficiency of cultivated land utilization (ECLU) and used the Super-SBM model to calculate the ECLU in the Yangtze River Delta (YRD) region in China. In addition, we also discussed the influencing factors of ECLU by the OLS model. Here we show that the ECLU was lower in cities with higher agricultural intensive utilization in the YRD. And in cities with better ecological conditions, the ECLU value obtained based on our adjusted ECLU assessment framework was higher than the traditional agricultural eco-efficiency assessment, indicating that the assessment method in this study paid more attention to ecological protection in the application. In addition, we found that crop diversity, paddy/dry land ratio, cultivated land fragmentation and terrain are the factors affecting the ECLU. This study helps provide a scientific basis for decision-makers to improve the ecological function of cultivated land based on ensuring food security and furthermore promote regional sustainable development.

Spatial and Temporal Patterns of Ecological Connectivity in the Ethnic Areas, Sichuan Province, China

With ongoing economic and social development, natural habitats are becoming increasingly fragmented, blocking habitat connections and reducing landscape connectivity. The study of changes in ecological connectivity can provide valuable information for habitat and landscape restoration, which are necessary for sustainable regional development. Despite the growing interest in this issue, studies that reveal the change in ecological connectivity in the compounded areas of ecological vulnerability and deep poverty are still lacking. In this paper, one of the most underdeveloped and ecologically fragile southwestern ethnic regions of China, the Sanzhou region of Sichuan Province, was the study area. Based on a vector map of current land-use status and vector data on ecosystem factors and nature reserves in 2010 and 2015, the change in ecological connectivity was analyzed using the minimum cumulative resistance model using GIS spatial analysis method. Firstly, ecological sources were identified based on the distribution of ecological functional areas. Secondly, the ecological resistance surface based on ecosystem service value is revised by integrating the three dimensions of topography and hydrology, ecological environment and development, and utilization intensity. Finally, the ecological connectivity of ethnic areas in southwest China in 2010 and 2015 was compared and analyzed through the perspective of ecological resistance. The results show that: (1) From 2010 to 2015, the overall ecological connectivity decreased. (2) There were six areas of high ecological resistance featuring human activity and ecological degradation: the Anning River Valley in Liangshan Prefecture, Ganzi, Dege and Luho counties in Ganzi Prefecture, and Ruoergai and Hongyuan counties in Aba Prefecture. (3) Low ecological resistance areas were more numerous and widely distributed, forming an ecological protection barrier for the three autonomous prefectures, and regulating and protecting their natural environments. It is necessary to maintain and strengthen this protection; accordingly, measures are proposed to improve ecological connectivity. This study provides a reference for achieving ecological security and harmonious coexistence between humans and nature in this region.

The Improvement Path for Regionally Coordinated Green Development: Evidence from Social Network Analysis

Regionally coordinated green development has been widely documented in China. However, most previous studies have investigated it from the perspective of linearity, while the spatial correlation of green development is nonlinear. Based on 48 cities in Bohai Rim, this study used a social network analysis to measure the spatial network, with an emphasis on the internal structure of regional green development, and analyzed the driving factors of regionally coordinated green development from the perspective of nonlinearity. We found that large cities have formed a "siphon effect" and that the polarization of eco-efficiency has become increasingly serious. There are limited connections, some of which are redundant, in the spatial network of green development, while the stability of the network is strong. Additionally, reducing the differences in environmental regulation approaches among cities can have a positive impact on the spatial correlation and spillover effect of green development, thereby promoting regionally coordinated green development among cities in the Bohai Rim.

Conflict or Coordination? Spatiotemporal Coupling of Urban Population-Land Spatial Patterns and Ecological Efficiency

The coordinated relationship between urban population–land spatial patterns (UPLSPs) and ecological efficiency (EE) is conducive not only to the rational utilization of resources and environment and the sustainable development of society, but also to the provision of a living environment that benefits public health. Identifying the coupling relationship of urban development and EE can provide critical information for urban planning. Previous studies have mainly focused on the coupling relationship between urban population and land, urbanization, and ecological development, while ignoring that between UPLSPs and EE. This study integrates several models to construct a novel framework for coupling UPLSPs and EE. Taking Hubei Province as the research area, we calculate the UPLSPs, EE, and their coupling coordination degree for 12 cities from 2000 to 2019. The paper offers several conclusions. (1) the urban population–land spatial matching degree increased, but the overall matching level was not high; the average value of EE showed an “N”-shaped change trajectory, and its overall level was low, with small changes and obvious regional differences. (2) The average value of the coupling coordination degree between UPLSPs and EE was a slow upward trend, with a radial distribution high in the middle and low in the periphery. There was conflict between the spatial patterns and EE, and the former restricted the development of the latter. (3) There were strong correlations between coordination degree and various indicators of UPLSPs and EE. While we should revitalize the stock of construction land and optimize the upgrading of the industrial structure, we also must coordinate human and land resources and the ecological environment, and narrow regional development differences. This study provides a new framework for urban environmental assessment and urban planning decision-making.

Efficiency Analysis of Land Use and the Degree of Coupling Link between Population Growth and Global Built-Up Area in the Subregion of West Africa

The main challenge for land use efficiency is population growth. Using a coupling coordination model and the Sustainable Development Goal 11.3.1 (Land Consumption Rate to Population Growth Rate, LCRPGR), the present study unravels the evolution of land use types and efficiency of land use in the Economic Community of West African States (ECOWAS) from 2003 to 2019. We interpreted the temporal land use types based on the long-time series Moderate Resolution Imaging Spectroradiometer (MCD12Q1-V6) land use images in 2003, 2007, 2011, 2015, and 2019. The World Bank data on population and socioeconomics were used to support the investigation on the coupled link. Our results showed that from 2003 to 2019, the total area of agricultural land decreased by −1.4%, while the built-up area expanded by 25.80%. Globally, the LCRPGR was 0.82, of which Cabo-Verdi and Niger had the highest (1.69) and lowest index (0.58), respectively. Correspondingly, the coupled coordination model indicated an overall value of 6.81, in which the highest and lowest value occurred in Liberia (29.78) and Niger (0.31), respectively. Furthermore, a rapidly growing population had become one of the most important factors causing inefficient land use in the study area. In summary, the ECOWAS was confronted with a lack of management to improve land use efficiency. Thus, future land use policies should pay more attention to balancing the coupled relationship between urban expansion and socio-economic interests.