Construction land development intensity is a spatial mapping of modern urbanization level, which integrally reflects urban development strategy, land use efficiency, and population carrying intensity. This article analyzed the spatial and temporal evolution of construction land development intensity using panel data of 31 provincial administrative divisions in China from 2002 to 2020, with the application of the Theil index and spatial autocorrelation. To further investigate the relationship between human activities and land development, the article used geographic detectors to analyze the influencing mechanisms. The results showed that: (1) The average intensity of construction land development of Chinese provinces from 2002 to 2020 showed a trend of "steady increase, a short decline, and then a steady increase," and there were significant differences in the characteristics of construction land development intensity changes in different regions. (2) The regional differences in construction land development intensity between provinces showed a decreasing trend. There were uneven differences among regions, with more minor regional differences in Central, South, and North China but more significant differences in Northwest, East, Southwest, and Northeast China. (3) The spatial agglomeration of construction land development intensity in the region increased initially and then decreased during the study period. The overall pattern was "small agglomeration and large dispersion." (4) Economic development factors such as GDP per land, industrial structure, and fixed asset investment completion significantly affect land development intensity. The interaction between the factors was apparent, and the effect of “1 + 1 > 2” was produced. Based on the study's results, it is suggested that scientific regional development planning, guiding inter-provincial factor flow, and rational control of land development efforts are the key to promoting sustainable regional development.

This study calculates the dynamic concentration index, explores the evolution of the relationship between the Dongxing port and city, and predicts its future. The results indicate that the relationship between the port and city has three development stages, namely the low-level balanced development stage (2001–2008), the port development stage (2009–2014), and the urban development stage (2015–2019). Based on the country (China and Vietnam), province (Guangxi Zhuang Autonomous Region), district (Fangchenggang City), county (Dongxing City), and individual (resident) levels, a multi-scale index system of influencing factors was developed. The impulse response function model analyzed the influential factors in the relationship between port and city development. The influence is as follows: country (China) > country (Vietnam) > county > individual > city > province. Finally, the relationship between port and city development was predicted using an auto-regression differential moving average model. It is expected that Dongxing City will gradually transition from a port- and city-dominated stage to a new stage of coordinated development. Thus, by improving the proportion of the secondary and tertiary industries, managing the population density, introducing foreign capital, enhancing the innovation level, and improving the traffic facilities, high-quality development in Dongxing port–city can be achieved.

By studying the structural characteristics and carbon storage of the mangrove island ecosystem in the Beibu Gulf, this study provides a scientific basis for mangrove ecological compensation in the coastal areas of Guangxi, South China Sea. On the basis of the unmanned aerial vehicle remote sensing images and a sample plot survey, the object-oriented multi-scale segmentation algorithm is used to extract the mangrove community type information, and one-way analysis of variance is conducted to analyse the structural characteristics of the mangrove community. The carbon storage and carbon density of different mangrove ecosystems were obtained based on the allometric growth equation of mangrove plants. The analysis yielded four main results. (1) The island group covers about 27.10 ha, 41.32% (11.20 ha) of which represents mangrove areas. The mangrove forest is widely distributed in the tidal flats around the islands. (2) The main mangrove types were Aegiceras corniculatum, Kandelia obovata + Aegiceras corniculatum, Avicennia marina + Aegiceras corniculatum and Avicennia marina communities. (3) Amongst the mangrove plants, Avicennia marina had the highest biomass (18.52 kg plant–1), followed by Kandelia obovata (7.84 kg plant–1) and Aegiceras corniculatum (3.85 kg plant–1). (4) The mangrove carbon density difference was significant. Kandelia obovata had the highest carbon density (148.03 t ha–1), followed by Avicennia marina (104.79 t ha–1) and Aegiceras corniculatum (99.24 t ha–1). The carbon storage of the mangrove island ecosystem was 1194.70 t, which was higher than in other areas with the same latitude. The carbon sequestration capacity of the mangrove was relatively strong.

This paper examines the trade-offs and synergies among the value of cultivated land resources, a critical consideration for ensuring farmers' livelihoods, supporting natural ecosystem management, and promoting integrated sustainable development in agroforestry systems. The study employs grids as accounting units for these resources, elucidating the economic-social-ecological trade-off/synergy mechanisms. It further clarifies the accounting results of cultivated land resource assets in Guangxi. The research utilizes methods such as spatial overlay, Spearman correlation, and the PPF model to comprehensively investigate the spatial heterogeneity, interrelationships, and optimal combinations under the trade-off/synergy relationship of cultivated land resource asset values. The results show that: (1) The total value of cultivated land resources in Guangxi is estimated at 12837.519 billion. Among the three types of values, ecological value (62.76%) exceeds both social value (32.98%) and economic value (4.26%), with all demonstrating pronounced spatial distribution characteristics in the central part. (2) The value of these cultivated land resource assets primarily stems from a strong trade-off and low synergy relationship concentrated in Guangxi's central region, while areas exhibiting high synergy and weak trade-off constitute 18.45% and 9.43%, respectively. (3) In most cities, the relationship between economic and social values tends to be synergistically enhancing, even overloaded, with a similar trend observed between economy-ecology and society-ecology trade-offs. Consequently, it is advisable to advocate for the recognition and articulation of the value inherent in cultivated land resource assets by introducing tailored strategies for enhancing value synergy. Such an approach can offer novel perspectives and technical assistance to both the theoretical framework and practical applications of natural resource asset value accounting.

Since the implementation of reform and opening up policy in 1978, the combined effects of cross-border cooperation, population movement and urbanization in the border areas have exacerbated land-use conflicts. Border areas are facing the unbalanced development in terms of the differences in geostrategic environments, resource endowments, and economic development. With an aim to achieve the optimal allocation of regional territorial resources and balanced development, it is crucial that the laws of spatial differences in territorial spatial evolution and its driving mechanisms under different development gradients can be scientifically identified. Using 45 border areas in China as examples, this study analyzed the evolution process and influencing factors of the "production-living-open-ecological" space by applying models such as territorial spatial dynamics, land-use transfer matrix and geodetector. The results showed that: (1) From 1980 to 2020, the production, living and open space in Chinese border areas expanded while the ecological space shrank. The structure of "one belt, three zones and multiple points" revealed the dramatic pattern. Given that the spatial composition of the border areas is dominated by the terrestrial ecological space composed of mountains, rivers and potential ecological space, the border zone holds tremendous value and potential including the ecological value and the service capacity. (2) The conflicts of territorial space in the border areas mainly occurred during the urbanization and opening to the outside world when the population and industrial agglomeration promote the mutual transformation, competition and integration between different spaces. The conversion type of territorial space was mainly the interconversion of production space, open space and ecological space. Consequently, the conflicts would lead to the increasingly significant regional differences. (3) The driving factors affecting different territorial spatial changes have varying effects, with economic dynamics and opening to the outside world being the main influencing factors for territorial spatial evolution in the border areas. Therefore, the relevant government departments from the border areas should comprehensively consider the characteristics of different regions, leverage their geographic advantages, and formulate differentiated zoning and regulatory strategies to promote the efficient utilization of territorial space and achieve the high-quality regional development.