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Carbon neutrality, achieved by increasing carbon sinks, is an effective strategy for solving the increasingly serious global climate change problem. The continuous exploitation of resources has damaged, the original ecosystem of mining cities leading to poor vegetation growth environment and decreased regional carbon sink capacity. Therefore, it is crucial to restore and enhance the ecological environment of the region and strengthen the carbon sink capacity of vegetation. However, studies on ecological spatial network optimization for mining cities are few. Here, we constructed the ecological spatial network of Xuzhou City, a mining city in China, using a modified minimal cumulative resistance model (MCR). Subsequently, we calculated the topological properties of ecological nodes and ecological spatial network in Xuzhou City by combining complex network theory with ecological network theory and proposed a scheme to optimize the landscape space based on ecological conditions. The functionality of ecological sources was determined by coupling the results of the Functional description of ecological sources by Remote Sensing Index (RSEI) and integral index of connectivity (dIIC). Carbon sinks were estimated by land use and the topological indicators were correlated with carbon sinks. Carbon sinks showed a significant positive correlation with betweenness centricity. We proposed an optimization strategy in accordance with the functionality and carbon sink capacity of ecological sources. Finally, we determined the effect of optimization by the change in robustness and carbon sink. The stability of the optimized ecological spatial network and ecological restoration capacity of Xuzhou City significantly improved, while the carbon sink was simultaneously enhanced. Through national ecological construction projects, restoration and renewal of ecological space can effectively enhance the carbon sink of mining cities, and thus achieve the goal of carbon neutrality. This study provides a theoretical and measure reference for future ecological engineering of mining cities. Additionally, it can also be applied in remote sensing to promote urban development and sustainability.

Enhancing and protecting biodiversity is a prerequisite for achieving “harmony between human beings and nature”. With the disturbance of human activities, the landscape pattern is constantly changing, changing the flow of species, information, and energy within the landscape, which in turn has a significant impact on biodiversity. Therefore, based on the InVEST model, this paper obtained the spatial distribution of biodiversity maintenance function and established a Chinese biodiversity conservation empowerment network through GIS spatial analysis. Based on the complex network theory, the dynamic evolution characteristics of the ecological spatial network structure were analyzed, and the relationship between its topological structure and the conservation of terrestrial biodiversity was revealed. The results show that: biodiversity maintenance function is high in south, southwest, and northeast China and low in the west, and ecological corridors also show a dense distribution in the east and sparse in the west. Over the past 20 years, the average biodiversity maintenance function has grown slowly, and the ecological community of the network has increased, the structure is more stable, and the connectivity is stronger. The weight degree, betweenness centrality, PageRank, and eigenvector centrality were significantly correlated with biodiversity maintenance function, indicating that ecological network structure plays a huge role in maintaining biodiversity. By focusing on building significant correlation sources, and constructing corridors to adjust network connections, the integrity and connectivity of important habitats will be gradually restored, so that ecological land biodiversity function can exert greater ecological benefits.

(1) Background: Eco−spatial networks play an important role in enhancing ecosystem services and landscape connectivity. It is necessary to study landscape structure optimization to achieve synergistic gains in network connectivity and ecosystem functionality. (2) Method: Based on remote sensing data, RS and GIS were used to evaluate the spatiotemporal changes in ecosystem services in China. Combined with complex network theory, the spatiotemporal evolution of China’s ecological spatial network and its topological structure from 2005 to 2020 is discussed. Network function–structure co−optimization was carried out using the edge augmentation strategy. (3) Result: The “three River resource” has high water conservation and high soil and water conservation in southeastern hilly areas. There is strong windbreak and sand fixation in southeastern Inner Mongolia. In the past 15 years, there have been about 8200 sources and about 14,000 corridors. The network has the characteristics of small−world and heterogeneity. After optimization, 18 sources and 3180 corridors are added, and the network connectivity and robustness are stronger. Finally, five regions are divided according to the network heterogeneity and corresponding protection and management countermeasures are proposed to provide scientific guidance for the country’s territorial space planning.

Forest and grass ecological space is the key component of the ecosystem and plays a vital role in regulating the carbon, water, and energy cycle. The long-term exploitation of forest and grass ecological space and huge population pressure have gradually degraded the function of China’s ecosystem. Therefore, forest and grass ecological space plays an important role in maintaining the stability of the ecosystem. The relationship between forest and grass ecospatial network structure and ecosystem service has been the focus of research. In this study, the forest and grass ecospatial network is constructed based on the minimum cumulative resistance (MCR) model. Then, the topological indicators (degree, weight clustering coefficient, node weight, unit weight, weight distribution difference, betweenness, PageRank) of the forest and grass ecospatial network were calculated by combining the complex network theory to analyze the relationship between these topological indicators and the three ecosystems (water retention, soil conservation, carbon storage). Based on the ecological significance of topological indicators, we identified ecologically fragile areas and proposed areas and directions for optimizing the ecospatial structure. Results show that the spatial distribution of the three ecosystem services in the southeast region of China is higher than that in the northwest region of China and shows a gradual decrease from the east to the west. The degree, node weight, unit weight, PageRank, and betweenness were highly significant and positively correlated with the three ecosystem services, among which PageRank had the highest correlation with water retention (p < 0.01, R2 = 0.835). Based on the spatial distribution characteristics of the different topological indicators, the quantitative relationship between the structural characteristics of the forest and grass ecospatial network and ecosystem services is clarified, revealing the intrinsic connection between ecological processes and ecosystem services. Through rational optimization of the forest and grass ecospatial network, ecosystem services can be effectively improved and ecosystem stability can be enhanced.

In the context of strengthening the construction of ecological civilization and accelerating the “carbon peak” in China, the regional ecological pattern and its connection with carbon sink capacity have become an urgent topic. Given that Inner Mongolia is a large carbon emission province and the conflict between economic development and ecological protection is particularly prominent, we took Inner Mongolia as an example to extract its ecospatial network, then calculated the integrity index, topological indices, and recovery robustness of the network and evaluated integrity and other properties of the ecospatial network structure by combining them with the ecological background. In addition, we analyzed the relationship between the topological indices and net primary productivity (NPP). The results showed that the network was scale-free and heterogeneous, with low integrity, connectivity and stability, which were the focus of future optimization. The nodes with important functions were mainly distributed in the farm-forest ecotone, grasslands, and the agro-pastoral ecotone; under the simulation attack, the node recovery robustness was stronger than the corridor recovery robustness, and NPP was negatively and significantly correlated with the woodland nodes and grassland nodes. In terms of ecological restoration, the unused land in the west is a key area, and it is necessary to add new ecological nodes and corridors. In terms of enhancing carbon sequestration capacity, under the premise of ensuring network connectivity, the appropriate and rational merging of ecological nodes and corridors within woodlands and grasslands is a particularly effective means. This study provides a reference for evaluating and optimizing the ecological pattern of areas with prominent ecological problems and improving the carbon sink of ecosystems in terms of their ecospatial network structure.