Spatial influence of ecological networks on land use intensity

Spatiotemporal pattern evolution analysis of ecological networks based on morphological spatial pattern analysis: a case study of Ningbo City, China

The exponential expansion of urban areas has precipitated a concomitant deterioration in the natural environment. Constructing ecological networks is vital in improving landscape connectivity, protecting biodiversity, and maintaining regional sustainable development. Ningbo, China, was set as the research area. Geographic information system and morphological spatial pattern analysis (MSPA) were used to determine the ecological source area. Subsequently, the corridor design model Linkage Mapper was used to ascertain and assess the linkages between the designated ecological source areas. The results showed that from 2000-2020, there was a large-scale change in land use type in Ningbo, with increasing complexity of patches and landscape fragmentation. The ecological sources of the three periods in Ningbo were primarily situated in the western, southern, and Hangzhou Bay coastal regions, exhibiting an uneven distribution in the eastern and western areas. The number of primary ecological corridors in Ningbo underwent a significant reduction, from 26 to 17, between the years 2000-2020. In terms of the distribution of ecological corridors, the primary corridors were concentrated in the central, southern, and western regions of the study area in 2000. By 2020, however, the primary ecological corridors within the study region were distributed mainly in a southerly direction. The interaction between north and south ecological sources was weakened, which adversely affected the species spread and ecosystem stability. After optimization, 12 ecological corridors and four ecological nodes were incorporated into Ningbo, 67 ecological breakpoints were identified, and four stepping stone patches were added. The study used spatiotemporal change trends, including land use type and landscape pattern, to examine the ecological network of Ningbo. In conclusion, the proposed optimization strategy is aligned with the current urban development context, offering a particularly pertinent reference point for Ningbo's ecological protection initiatives.

Spatial differentiation and coupling between village development intensity and landscape pattern of 100 villages in Anhui, China

Spatial development and landscape pattern are fundamental elements of the land system of village. Analysing the spatial differentiation and coupling relationship between spatial development intensity and landscape pattern is of great significance for the development and protection of village land resources. In order to address the current research lack on the coupling response between village spatial development intensity and landscape pattern, a technical method for analysing the spatial differentiation and coupling relationship between village spatial development intensity and landscape pattern is constructed based on the methods of village spatial development intensity model, landscape pattern index, bivariate spatial autocorrelation model, coupling degree and coupling coordination degree model. Taking 100 villages in Anhui Province, China as an example, the spatial distribution characteristics and coupling characteristics of village spatial development intensity and landscape pattern are analysed. The results show that there are obvious regional differences in the spatial distribution of village spatial development intensity and landscape pattern in Anhui Province. The village spatial development intensity shows a pattern of the Northern Anhui plain region (NAPR) > along the Yangtze River plain region (YRPR) > Jiang-huai Hilly region (JHHR) > Southern Anhui mountainous region (SAMR) > Western Anhui mountainous region (WAMR). The village landscape pattern in NAPR and YRPR are high fragmentation, while the village in JHHR has the lowest fragmentation, and the villages in SAMR and WAMR show relatively low fragmentation. The spatial coupling relationship between village spatial development intensity and landscape pattern is mainly characterised by high-high clustering and low-high clustering. The coupling coordinated development of villages in NAPR is the best, followed by YRPR, JHHR and SAMR, and WAMR is the worst. There is only a significant multi-linear relationship between village landscape pattern and multiple spatial development intensity indicators in WAMR and NAPR. The spatial differentiation and coupling relationship are influenced by both natural geographical factors and human activity factors. Finally, the study puts forward some targeted countermeasures and suggestions. The research results can provide theoretical method and practical application reference for village land space development and protection and village planning.

Spatial response of urban land use intensity to ecological networks: a case study of Xi'an Metropolitan Region, China

In the face of the persistent degradation of ecological environments and fragmentation of ecological networks brought about by rapid urbanization, this study focuses on examining the interaction between urban land use intensity and ecological networks in the Xi'an Metropolitan Region (XAMR), China, and their impact on ecological equilibrium and sustainable development. By comprehensively evaluating the changes in land use intensity in XAMR from 2010 to 2020, the aim is to underscore the pivotal role of ecological networks in maintaining urban ecological balance and promoting sustainable development. The findings indicate a transition in land use intensity in the XAMR from low to high concentration, reflecting an intensification in land resource utilization during urbanization. However, the establishment and management of ecological networks can significantly enhance urban ecological security and biodiversity. Notably, this research identified crucial ecological corridors and source areas, augmenting the connectivity of urban green infrastructure and providing vital support for urban biodiversity. Additionally, a significant finding of this study is the spatial spillover effects generated by socioeconomic factors such as the proportion of tertiary and secondary industries and per capita GDP through the ecological network, which have profound impacts on land use intensity in the surrounding areas. These insights offer a novel understanding of the complex interactions within urban ecosystems, emphasizing the importance of incorporating ecological network construction in urban planning. Overall, through a comprehensive analysis of the relationship between the ecological network and land use intensity in the XAMR, this study proposes new directions for urban ecosystem management and land use planning, highlighting the significance of scientific ecological network planning and management in achieving long-term sustainable development in urbanization processes.

Spatial constraints or spatial dynamics? The spatial spillover effect of networks of flood regulation service flows on land-use degree

In the face of frequent floods under climate and environmental changes, it is particularly important to measure the supply and demand of flood regulation services. Using the Hainan Island as an illustrative case, this study constructs a spatial spillover model to examine the spatial correlation mode and evolution of regional land-use degree through the network of ecosystem service flow. The research results show that forests, grasslands, and reservoirs function as the primary suppliers of flood regulation services, with forests contributing significantly to the regulation of floods. High flood risk was identified in the eastern, northern, and western regions of the Hainan Island, corresponding to increased demand for flood regulation services in croplands, towns, and rural settlements within these areas. The flow of flood regulation services within the Hainan Island was found to be directed from the center to the surrounding areas, with medium and high service flows predominantly concentrated in the northern and surrounding regions. The degree of land use on the Hainan Island demonstrated an influence on socio-economic development. Additionally, the flow network of ecological services was identified as a crucial factor in spatial spillovers, reflecting the level of interaction between county units.

Coupling strength of human-natural systems mediates the response of ecosystem services to land use change

Addressing the dynamics of human-natural systems (HNS) driven by land use change (LC) is a key challenge for the sustainable development of ecosystem services (ES). However, how changes to the HNS coupling relationships affect ES is rarely reported. We used network analysis methods to construct an HNS correlation network in the Loess Plateau based on the correlation between the main components of HNS, such as ES, human factors, landscape pattern, vegetation cover, climate change and geomorphic characteristics, and quantitatively described the HNS coupling relationships through key network attributes. We analyzed the variation in HNS network attributes and their relationships with ES along an LC intensity gradient. The results show that carbon storage and soil conservation in the Loess Plateau increased by 0.56% and 0.26%, respectively, during the study period, while the habitat quality and water yield decreased by 0.11% and 0.18%, respectively. An increase in LC intensity reduces connectivity and density in the HNS network, which results in looser connections among HNS components. Importantly, we found that HNS network attributes explained 85% of ES variation across different LC intensity gradients and that connectivity and density had the strongest explanatory power. This means that LC mainly affects ES dynamics by changing the coupling strength of HNS. Our research offers a new perspective for linking LC-HNS-ES, which will help guide practitioners toward establishing and maintaining the sustainability of human well-being amidst changing HNS.

Construction and optimization strategy of ecological security pattern based on ecosystem services and landscape connectivity: a case study of Guizhou Province, China

Rapid urbanization and irrational human activities have induced in numerous environmental problems, seriously threatening regional ecological security. The establishment and optimization of ecological security patterns (ESPs) were considered as a nature-based solution and an effective way for sustainable development. In this study, the Guizhou Province, a representative karst mountainous region in the southwest of China, was used as the study region. The ecological sources were identified and optimized through integrating ecosystem services and landscape connectivity, and the ecological resistance surface was corrected by representative features of karst areas. The circuit theory was adopted to extract the ecological corridors and barriers. We found that the three ecosystem services (i.e., water conservation, biodiversity maintenance, and soil conservation) had remarkable spatial heterogeneity. The area of optimized ecological sources was enlarged 4752.14 km². The number of corridors was reduced from 73 to 47 after optimization, with a total length decreased by 1251.97 km. The optimized ecological network structure considerably enhanced ecological connectivity, among the γ index increased by 0.0014, the β index reduced by 0.0833, while the α index did not change significantly. We concluded that quantitatively exploring the impacts of ecological source optimization are significant for enhancing ecological connectivity. The approach of our study proposes a novel idea into the ESP construction that can provide a meaningful reference for ecological protection and restoration.

Effect of fencing on regional ecological networks in the northern Tibetan Plateau

Fencing is an essential measure for the rehabilitation and conservation of grasslands on the Qinghai-Tibet Plateau. However, its construction could change the distribution and migration of wildlife, thus affecting the integrity of the ecological networks for local wild animal movement. It is of great significance to quantify the potential impact of fencing on ecological network connectivity associated with land-use changes at regional scale. In this study, taking the northern Tibetan Plateau as the study area, we explored the ecological network change using circuit theory approach under different scenarios at county scale. Among them, this study set up four different scenarios according to the economic growth rate, population growth rate and the sustainable development of society and environment. The results showed that: 1) with increased grazing intensity and enhanced human activities from 1990 to 2015, the grasslands of the northern Tibetan Plateau were greatly degraded, most of which was converted into the barren land, and the conversion proportion was as high as 90.84%, which lead to a decreasing trend of the current density of ecological network in most counties and deterioration of ecological connectivity; 2) fencing construction has reduced regional current density, while fencing intensity is positively correlated with current density loss at county scale. Among them, the counties with serious current density loss were distributed in the northwest and southeast regions. The maximum loss ratio is 39.23%; 3) under four different future land use scenarios, coordinated economic, social and environmental development will have a positive effect on the ecological network. The results of the study have important ecological significance for developing reasonable conservation measures for grassland restoration, protecting wildlife, and maintaining regional ecological balance.

Quantifying the Relationship between Land Use Intensity and Ecosystem Services' Value in the Hanjiang River Basin: A Case Study of the Hubei Section

An increased land use intensity due to rapid urbanization and socio-economic development would alter the structure and function of regional ecosystems and cause prominent environmental problems. Revealing the impact of land use intensity on ecosystem services (ES) would provide guidance for more informed decision making to promote the sustainable development of human and natural systems. In this study, we selected the Hanjiang River Basin (HRB) in Hubei Province (China) as our study area, explored the correlation between land use intensity and ecosystem Services' Value (ESV), and investigated impacts of natural and socio-economic factors on ESV variations based on the Geographical Detector Model (GDM) and Geographically Weighted Regression (GWR). The results show that (1) from 2000 to 2020, land use intensity in HRB generally showed an upward trend, with a high spatial agglomeration in the southeast and low in the northwest; (2) the total ESV increased from 295.56 billion CNY in 2000 to 296.93 billion CNY in 2010, and then decreased to 295.63 CNY in 2020, exhibiting an inverted U-shaped trend, with regulation services contributing the most to ESV; (3) land use intensity and ESV had a strong negative spatial correlation, with LH (low land use intensity vs. high ESV) aggregations mainly distributed in the northwest, whereas HL (high land use intensity vs. low ESV) aggregations were located in the southeast; (4) natural factors, including annual mean temperature, the percentage of forest land, and slope were positively associated with ESV, while socio-economic factors, including GDP and population density, were negatively associated with ESV. To achieve the coordinated development of the socio-economy and the environment, ES should be incorporated into spatial planning and socio-economic development policies.

Construction and Optimization Strategy of an Ecological Network in Mountainous Areas: A Case Study in Southwestern Hubei Province, China

High-intensity urban development and economic exploitation have led to the fragmentation and isolation of regional habitat patches, and biodiversity is under serious threat. Scientific identification and effective optimization of ecological networks are essential for maintaining and restoring regional ecosystem connectivity and guiding sustainable socio-economic development. Taking the mountainous areas of southwest Hubei Province (MASHP) in central China as an example, this study first developed a new integrated approach to identify ecological sources based on a quantitative assessment of ecosystem services and the morphological spatial pattern analysis (MSPA) method; it then used the Linkage Mapper tool to extract ecological corridors, applied the principle of hydrological analysis to identify ecological nodes, evaluated each ecological element to quantify its importance, and finally constructed the ecological network and further proposed some optimization countermeasures. The results show that the ecological network in the MASHP is dominated by ecological resources composed of forestland. Connectivity in the central region is significantly better than in other regions, including 49 ecological sources with an area of 3837.92 km2, 125 ecological corridors with a total length of 2014.61 km, and 46 ecological nodes. According to the spatial distribution of crucial ecological landscape elements, a complete and systematic ecological framework of “two verticals, three belts, three groups, and multiple nodes” was proposed. The internal optimization of the ecological network in mountainous areas should focus on improving ecological flow, and strategies such as enhancing the internal connectivity of ecosystems, unblocking ecological corridors, and dividing ecological functional zones can be adopted. Based on the above analyses, this study also made recommendations for ecological protection and development and construction planning in mountainous areas. This study can provide realistic paths and scientific guidelines for ecological security and high-quality development in the MASHP, and it can also have implications for the construction of ecological networks and comprehensive ecological management in other mountainous areas.

Changes in ecological networks and eco-environmental effects on urban ecosystem in China's typical urban agglomerations

Exploring the changes in ecological networks (ENs), its eco-environment effects and the differences in urban agglomerations in various urbanization stages are important for achieving sustainable ecosystem management and a better layout of ecological network. In this study, China's three typical urbanization agglomerations, Beijing-Tianjin-Hebei urban agglomeration (BTH), Yangtze River Delta urban agglomeration (YRD), and Pearl River Delta urban agglomeration (PRD), were selected as the study area. Spatiotemporal changes in ENs, the changing patterns, its eco-environment effects, and impacts of rapid urbanization were analyzed by environment indices, buffer analysis, and correlation analysis. The results showed a great lost in ENs from 2000 to 2015. Four patterns were seen in changing ENs: decomposition process (DP), internal change process (ICP), polycondensation process (PP), and external change process (ECP). ICP was dominated in YRD and PRD. ECP was the main pattern in core areas of BTH. The correlation analysis with YRD as the example showed that the changes in ENs had a certain impact on the eco-environment, especially in the 10-km buffer zone. The decrease of ENs was related to the increase of developed land, and the closer to the core area, the higher the correlation coefficient was. Reduction of ENs would slow down to a certain extent, when the agglomeration is in a higher urbanization stage. Different directions of restoration and optimization of ENs were proposed for the three urban agglomerations. The study will provide support for sustainable management and restoration and optimization of ENs for China's agglomerations.

Evolution Analysis of Ecological Networks Based on Spatial Distribution Data of Land Use Types Monitored by Remote Sensing in Wuhan Urban Agglomeration, China, from 2000 to 2020

Construction and protection of ecological networks (ENs) is considered to be an effective means to curb habitat fragmentation and strengthen landscape connectivity. In this study, a complete evaluation framework of ENs based on “quality–function–structure” was proposed to support the formulation of protection strategies for ENs. First, we built the ENs of Wuhan urban agglomeration (WUA) from 2000 to 2020 based on the advantages of circuit theory and remote sensing data of land use monitoring. The results showed that land development activities are an important driving force for the temporal and spatial evolution of global ENs. Forest fragmentation, transitional urban expansion, and agricultural reclamation were important inducements for the shrinkage of ecological sources. They may also increase the resistance of species migration, which will lead to qualitative change and even fracture of ecological corridors. Second, circuit theory, centrality index, and complex network theory were applied to evaluate the quality defects, functional connectivity, and topology characteristics of ENs in WUA, respectively, from 2000 to 2020. The results showed that the antagonism between ecological corridors and land development activities led to ecological quality defects (ecological barriers and pinchpoints). Different land development models had differential effects on centrality indexes. Moreover, the main trunk in the northern Dabie Mountains and the southern Mufu mountains was developed, while the secondary trunks were abundant in the middle of WUA. Finally, we proposed protection strategies for ENs based on the coupling of the “quality–function–structure” of WUA in 2020. It is suggested that all ecological sources must be included in nature reserves to prevent natural or manmade erosion. The key areas to be repaired were determined through the quality evaluation of ecological corridors. The priority of construction and protection of ecological corridors was determined by coupling two topological structures and functions. We argue that specific protection strategies and directions can be determined according to the construction objectives of local ENs.

Construction of Landscape Ecological Security Pattern in the Zhundong Region, Xinjiang, NW China

The Xinjiang Zhundong Economic and Technological Development Zone, which contains the largest coalfield in China, is a mega energy base for west–east gas transmission and outbound electricity transmission in China; however, resource exploitation and the region’s arid climate have led to the region’s ecological environment being increasingly vulnerable. The morphological spatial pattern analysis (MSPA) method and landscape connectivity were used in this study to identify the ecological sources and extract the ecological corridors and ecological nodes based on the minimum cumulative resistance (MCR) model, used to construct the landscape ecological security pattern in the Zhundong region from 2016 to 2021. The results show that (a) from 2016 to 2021, the area of ecological sources increased by 117.86 ha and the distribution density of which decreased from the southern-central region to the northern and northwestern regions. (b) From 2016 to 2021, the number of ecological corridors and ecological nodes decreased, and the ecological corridors with dense distributions in the south gradually moved to the north and west. The length of the ecological corridors in the south gradually became longer, and the number of ecological corridors connecting the east and west in the north increased. (c) The landscape ecological security pattern of the Zhundong region was constructed by “a network and multiple points” using the model of ecological sources–ecological corridors–ecological nodes. The findings of this study provide a scientific foundation for the construction of an ecological security development plan and the ecologically protective development of coal resources in Zhundong.

Information entropy and elasticity analysis of the land use structure change influencing eco-environmental quality in Qinghai-Tibet Plateau from 1990 to 2015

Regional land use change affects eco-environmental quality by altering ecosystem structure and function. The primitive ecosystem and environment of the Qinghai-Tibet Plateau (QTP) occupies a special position in the world, but it is very fragile. Although land use activities on the plateau have increased gradually in past decades, its effects on eco-environmental quality and the underlying mechanisms of regional heterogeneity remain unclear. In this study, an eco-environmental quality assessment index system was established to characterize the QTP, and the information entropy and elasticity methods were introduced to quantify the impact of land use dynamic trajectory on the eco-environmental quality. It provides a statistical measurement of system structure and more information than the traditional methods to reveal the land use change. The area change in land use on QTP was small from 1990 to 2015. The unused land and forest decreased, but those of grassland, water body, built-up land, and cultivated land increased. The overall eco-environmental quality on the QTP was low, and increased at a rate of 9.39% over the past 25 years, presenting a distribution of decreasing from southeast to northwest. The improvement in eco-environmental quality attributed to land use change was mainly due to the conversion of unused land into grassland, and ecological conservation projects also improved the local ecological environment. Conversely, the expansion of built-up land and land degradation contributed to decline in local eco-environmental quality in the Hengduan Mountains, northeastern plateau, and Qaidam Basin. The results indicated that under the influence of climate change, the changes in land use and eco-environmental quality were inconsistent in part regions, mainly including the central and southern Tibet and the border zone. Regions in which eco-environmental quality has been degraded by unreasonable land use are urgent to optimize land use management.

Spatiotemporal Evaluation and Driving Mechanism of Land Ecological Security in Yan’an, a Typical Hill-Gully Region of China’s Loess Plateau, from 2000 to 2018

Forest landscape restoration and ecosystem of Loess Plateau have enhanced prominently, since the policy implementation (1999) of the Grain for Green Project in China. Land ecological security (LES) performs an extremely critical function for protecting vulnerable land resources and sustaining forest ecosystem stability. Predecessors’ studies substantially concentrate on biophysical and meteorologic variables using numerous grounded methodologies, little research has been launched on systematic natural-socio-economic-ecological relationships and how these contributions and regulations for LES evaluation. Here, pressure-state-response (PSR) model was used to establish the evaluation system of LES in regional-scale, and LES was classified into five levels measured by ecological security index (S), including high (S ≥ 0.75), medium−high (0.65 ≤ S < 0.75), medium (0.55 ≤ S < 0.65), medium−low (0.45 ≤ S < 0.55), and low (S < 0.45) level, for systematically analyzing its spatiotemporal distribution characteristic and response mechanism to explanatory variables in Yan’an, northwest China, from 2000 to 2018. The results demonstrated that: (1) LES status was mainly characterized by medium−high level and medium level, and maintained profound stability. (2) zone with medium−high LES level was mainly concentrated in western and southern regions, continuously expanding to northeast regions, and possessed the largest territorial area, accounting for 37.22–46.27% of the total area in Yan’an. (3) LES was primarily susceptible to normalized differential vegetation index, vegetation coverage, and land surface temperature with their optimal impacting thresholds of 0.20–0.64, 0.20–0.55, and 11.20–13.00 °C, respectively. (4) Normalized differential vegetation index and vegetation coverage had a significant synergistic effect upon LES based on their interactive explanation rate of 31% and had significant variation consistency (positive and negative) with LES, which were powerfully suggested to signal the intensification of the regional eco-security level in the persistent eco-greening process.

Identification of ecological networks and nodes in Fujian province based on green and blue corridors

China's Green Space System Planning (GSSP) research has gradually expanded from central urban areas to municipal and provincial scales in recent years. Besides, the research on the role of green space in the water environment has also attracted much attention. However, the study of green corridors usually ignored hydrological data, which widespread absence especially in the large area scale. And the scale of green corridor construction mainly focused on central urban areas. This paper took China's Fujian province as an example. Based on the DEM elevation data, the article identified blue corridors without hydrological data. In addition, the green corridors were determined based on the land use data. According to the green corridors and blue corridors protection, we identified the ecological networks and nodes by the network analysis method. The results showed that the blue corridors identified by DEM data were consistent with the hydrological status quo. The regional status of the identified ecological networks and nodes were basically in line with their characteristics, proving the value of the planning methods. Finally, based on the identification results, suggestions for Fujian's ecological networks and nodes are put forward.

Spatiotemporal pattern and coordination relationship between urban residential land price and land use intensity in 31 provinces and cities in China

The trend towards efficient and intensive use of land resources is an inevitable outcome of current social development. The rational matching of urban land prices and land use intensity has become an important factor under accelerating urbanization, and promotes the healthy development of the social economy. Using data on residential land price and on land use intensity for 31 provinces and cities in China, we employ the E-G cointegration test and quadrant map classification to determine the coordination relationship between land price and land use intensity. We then employ HR coordination to calculate the coordination degree of land price and land use intensity, and classify the coordination type accordingly. Our results are as follows. (1) The spatio-temporal distribution of urban land price shows high variability with multiple maxima, and follows a decreasing trend from the southeast coastal area to the northwest inland area and the northeast. (2) The overall land use intensity is at or above the middle level, and shows large spatial differences between provinces, but the agglomeration between provinces is increasing. (3) From the perspective of the relationship between urban land price and land use intensity at the inter-provincial scale, we find that the land price and land use intensity are well coordinated, and the number of provinces has been dynamically changing during different development periods. There is an east-west difference in the spatial distribution of land price and land use intensity coordination level. Different provinces and cities with the same coordination stage show differences in their land price and land use intensity level.

The Spatial Effect of Administrative Division on Land-Use Intensity

Land-use intensity (LUI) is one of the most direct manifestations of regional land use efficiency. The study of cross-administrative LUI in urban agglomerations is of great importance for the sustainable development of land, new urbanization, and territorial spatial planning. In this study, the urban agglomeration in the middle reaches of the Yangtze River in China was used as the case study area to explore the spatial spillover effect through the administrative division, underlying driving mechanism, and spatial interactions or constraints of LUI. First, LUI was measured using the index of the proportion of construction land to the total area of the administrative region. Second, the adjacency relationship of the county-level administrative units was identified on the basis of the queen-type adjacency criterion under the county-level administrative division system. Thereafter, spatial weight matrix for spatial modeling was constructed. Last, a spatial model using the “Spatial adjacency matrix” was devised to examine the influencing factors and the potential spatial interactions or constraints of administrative units. Results revealed that the level of LUI of different county-level administrative units were quite different, and the gap of LUI among county-level administrative units widened from 2010 to 2017. The fixed asset investment per land (FAIL), gross domestic product per capital (PGDP), and proportion of tertiary sector (PTS) are the driving factors of LUI. County-level administrative units not only had a significant and increasing spatial interaction effect based on the relationship of cooperation, but also had an influence of restraint mutually which was caused by the competition. The direct spatial spillover effect was remarkable. In the future, the effect of interaction among administrative units under the administrative division should be considered to promote the reasonable use and optimal layout of regional urban land to realize the optimal allocation of land resources.

Identifying Ecological Corridors and Networks in Mountainous Areas

Since the 1950s, human activities have been driving economic development and land changes, hindering the conservation of biological habitats and landscape connectivity. Constructing ecological networks is an effective means to avoid habitat destruction and fragmentation. Mountain areas are hotspots of biological habitats and biodiversity; however, the pace of urbanization in mountain areas is also accelerating. To protect an ecosystem more effectively, it is necessary to identify ecological corridors and ecological networks. Therefore, based on the Minimal Cumulative Resistance model and taking Chongqing in China as an example, the identification of potential ecological corridors and the construction of an ecological network in Chongqing were realized using the Linkage Mapper software. The results were as follows: (1) From 2005 to 2015, the patch area of cultivated land and grassland in Chongqing decreased by 0.08% and 1.46%, respectively, while that of built-up areas increased by 1.5%. The fragmentation degree of cultivated land was higher, and the internal connectivity of forestry areas was worse. (2) In total, 24 ecological sources were selected, and 87 potential ecological corridors and 35 ecological nodes were generated using the Morphological Spatial Pattern Analysis and the Conefor2.6 software. The total length of the ecological network in Chongqing is 2524.34 km, with an average corridor length of 29.02 km. (3) The overall complexity and network efficiency are high, but the spatial distribution of ecological corridors is uneven, especially in the southwest of Chongqing.

Land suitability assessment for supporting transport planning based on carrying capacity and construction demand

With the rapid global urbanization, the unlimited increasing transportation infrastructure has met the needs of urban expansion, but it has caused a series of ecological problems lacking consideration of ecological conservation. The land suitability assessment for supporting transport planning based on carrying capacity and demand for construction is an effective way to promote urban socioeconomic development and ecological conservation. Therefore, we constructed a logical framework of resources and environment supporting, traffic construction demand driving, and ecological protection red line and basic farmland constraining, and applied the analytic hierarchy process (AHP), GIS, three-dimensional magic cube method, and gravity model to evaluate the suitability of expressway development in Sichuan Province, China. The results showed that the spatial difference in the carrying capacity of resources and environment and the demand for expressway construction was relatively high in Sichuan, and those in eastern cities were even higher. The land suitability for supporting transport planning was relatively high, and the suitable areas with a grade from 8 to 10, accounted for 20.77% of the total study area, which could almost meet the demand for transportation infrastructure construction. The land suitability performed a circle structure with Chengdu as the core and gradually decreasing to the periphery. Overall, this study adds new insights to transport planning reform in other similar regions around the world and can provide important references for regional development planning and environmental protection.

Ecological Network Optimization in Urban Central District Based on Complex Network Theory: A Case Study with the Urban Central District of Harbin

Habitat destruction and declining ecosystem service levels caused by urban expansion have led to increased ecological risks in cities, and ecological network optimization has become the main way to resolve this contradiction. Here, we used landscape patterns, meteorological and hydrological data as data sources, applied the complex network theory, landscape ecology, and spatial analysis technology, a quantitative analysis of the current state of landscape pattern characteristics in the central district of Harbin was conducted. The minimum cumulative resistance was used to extract the ecological network of the study area. Optimized the ecological network by edge-adding of the complex network theory, compared the optimizing effects of different edge-adding strategies by using robustness analysis, and put forward an effective way to optimize the ecological network of the study area. The results demonstrate that: The ecological patches of Daowai, Xiangfang, Nangang, and other old districts in the study area are small in size, fewer in number, strongly fragmented, with a single external morphology, and high internal porosity. While the ecological patches in the new districts of Songbei, Hulan, and Acheng have a relatively good foundation. And ecological network connectivity in the study area is generally poor, the ecological corridors are relatively sparse and scattered, the connections between various ecological sources of the corridors are not close. Comparing different edge-adding strategies of complex network theory, the low-degree-first strategy has the most outstanding performance in the robustness test. The low-degree-first strategy was used to optimize the ecological network of the study area, 43 ecological corridors are added. After the optimization, the large and the small ecological corridors are evenly distributed to form a complete network, the optimized ecological network will be significantly more connected, resilient, and resistant to interference, the ecological flow transmission will be more efficient.

Effect of Complex Road Networks on Intensive Land Use in China’s Beijing-Tianjin-Hebei Urban Agglomeration

Coupled with rapid urbanization and urban expansion, the spatial relationship between transportation development and land use has gained growing interest among researchers and policy makers. In this paper, a complex network model and land use intensity assessment were integrated into a spatial econometric model to explore the spatial spillover effect of the road network on intensive land use patterns in China’s Beijing–Tianjin–Hebei (BTH) urban agglomeration. First, population density, point of interest (POI) density, and aggregation index were selected to measure land use intensity from social, physical, and ecological aspects. Then, the indicator of average degree (i.e., connections between counties) was used to measure the characteristics of the road network. Under the hypothesis that the road network functions in shaping land use patterns, a spatial econometric model with the road network embedded spatial weight matrix was established. Our results revealed that, while the land use intensity in the BTH urban agglomeration increased from 2010 to 2015, the road network became increasingly complex with greater spatial heterogeneity. The spatial lag coefficients of land use intensity were positively significant in both years and showed a declining trend. The spatially lagged effects of sector structure, fixed asset investment, and consumption were also significant in most of our spatial econometric models, and their contributions to the total spillover effect increased from 2010 to 2015. This study contributes to the literature by providing an innovative quantitative method to analyze the spatial spillover effect of the road network on intensive land use. We suggest that the spatial spillover effect of the road network could be strengthened in the urban–rural interface areas by improving accessibility and promoting population, resource, and technology flows.

Can the establishment of ecological security patterns improve ecological protection? An example of Nanchang, China

Establishing ecological security patterns provides new ideas for maintaining regional ecological security. Methods for establishing these patterns have been extensively investigated in several studies, but the ecological protection effects of these patterns need further examination. Nanchang is the capital city of Jiangxi province and a typical representative of rapidly developing cities. With the proposal of an ecological environment protection plan for Nanchang metropolitan area, the coordinated development of ecology, economy and society has become the local development goal. This study used Nanchang City as an example for the establishment of an ecological security pattern through the circuit theory. The ecological sources of a 1068.56 km² location and 20 ecological corridors with a total area of 957.39 km² were identified. Three development scenarios in 2015-2040 were set up, namely, unrestricted development (UD), core area protection (CP) and ecological security pattern restriction (ESPR) scenarios. The UD scenario followed the land expansion rate from 2010 to 2015. The CP scenario used a nature reserve as a forbidden conversion area. Under the ESPR scenario, ecological security pattern was regarded as a prohibited conversion area. The CLUMondo model was used in simulating land use and evaluating the ecological protection effects of the scenarios. Through comparison, we determined that the ecological security indices under UD, CP and ESPR were 0.230, 0.242 and 0.249, respectively, from the perspective of the overall ecological security of the region. In the evaluation of the landscape characteristics of EL, under ESPR, the landscape connectivity was the best. The detailed analysis results showed that the ecological security pattern not only could protect the regional ecological security on the regional scale but also had an outstanding protection effect on the local scale. In summary, compared with the UD and CP scenarios, ecological security patterns had a better effect on regional ecological protection.