In the process of rapid urbanization, the decline in ecosystems' physical supply value is a direct result of the increasing demands of human development. The ecosystem services value combined with supply and demand factors can be used to obtain the ecosystem services scarcity value (ESSV). These ecosystems with larger ESSVs warrant increased protection, or at the very least a development plan to ensure a balance between their continued existence and human usage. However, urbanization and other developmental effects have often caused the ESSV of those regions to be disregarded, which produces an imbalance in the ecosystem. This paper evaluated the spatial differentiation of ESSV based on heterogeneous units in the Yuebei region, China. Then, a spatial response analysis of the ESSV to urbanization according to the spatial correlation model and Getis-Ord Gi* was conducted. The results showed that the ecosystem service physical supply value declined due to urban sprawl in 1990-2015, but the ESSV increased sharply during the same time with its acceleration being particularly strong after 2000. Areas with higher ESSV were concentrated in the northern region due to a higher prevalence of woodland. Urbanization accelerated significantly after 2000, and it is found that similar tendencies of ESSV and urbanization occurred over the same period. Surprisingly, the ESSV was negatively correlated with urbanization in local regions, and their interaction continued to increase over time. The spatial hotspot map of the ESSV and urbanization also formed an opposite pattern. In addition, the grid number of High-Low and Low-High types is more than half of the total number of aggregated grids. According to the results, understanding the variation in the ESSV clearly due to urbanization and identifying their interaction in local regions can provide a more specific direction for future resource adjustment and ecosystem service improvements.
Accelerated urbanization has changed land use patterns, leading to the deterioration of ecosystems. Assessments of ecosystem health (ESH) during the urbanization process are used to determine the reasons and mechanism for this, and to uncover negative factors. In this study, we assessed the ESH of Qiannan prefecture, in Guizhou Province, China, based on the ecosystem services value. We selected a series of indicators, including natural, social, and economic aspects, to detect the impact of urbanization on ecosystem services in 1990, 1995, 2000, 2005, 2010, and 2015. The results show that ESH in Qiannan declined from 1990 to 2015, especially in the eastern and northern regions. Further, the results indicate that urbanization had a negative impact on ESH, of which the dominant factor was the proportion of construction land from 1990 to 2005. After 2005, moreover, the dominant factor was the gross domestic product. The impact of urbanization on EHS had spatial differences, however. The most significant negative impact was found in the east and north. After 2010, the western and central regions of Qiannan showed an urbanization trend in favor of ecosystem health. We recommend ecological restoration in regions with weak and relatively weak ESH levels to achieve sustainable development.
Studying the impact of large-scale ecological projects, such as the Grain-for-Green Program (GGP), on ecosystem services (ES) is currently a frontier and hot topic of ecological research. The GGP can directly change land use and land cover, thus affecting ES. By comparing the changes of ecosystem service value (ESV) and ecosystem service scarcity value (ESSV) in Qinghai before and after the implementation of the GGP, this paper clarified the impact of the GGP on Qinghai from the angles of ecology and economics. This paper quantified and evaluated the land use dynamics, ESV, and ESSV in Qinghai from 1995 to 2020. The results showed that in the past 25 years, the total annual Normalized Difference Vegetation Index (NDVI) of Qinghai showed a trend of sustained growth. From 1995 to 2020, the ESV increased by 6.80%. After considering supply and demand, the ESSV showed a continuous upward trend, increasing by 719.38%. After implementation of the GGP, the increase of NDVI inhibited the increase of the ESSV. These findings from evaluation of the effect of the GGP implementation provide a theoretical basis for future policy implementation and, in particular, a reference for the evaluation of the ESV and the ESSV in Qinghai.
The past decades have witnessed rapid urbanization around the world. This is particularly evident in Zhuhai City, given its status as one of the earliest special economic zones in China. After experiencing rapid urbanization for decades, the level of ecosystem health (ESH) in Zhuhai City has become a focus of attention. Assessments of urban ESH and spatial correlations between urbanization and ESH not only reveal the states of urban ecosystems and the extent to which urbanization affected these ecosystems, but also provide new insights into sustainable eco-environmental planning and resource management. In this study, we assessed the ESH of Zhuhai City using a selected set of natural, social and economic indicators. The data used include Landsat Thematic Mapper images and socio-economic data of 1999, 2005, 2009 and 2013. The results showed that the overall ESH value and ecosystem service function have been on the decline while Zhuhai City has continued to become more urbanized. The total ESH health level trended downward and the area ratio of weak and relatively weak health level increased significantly, while the areas of well and relatively well healthy state decreased since 1999. The spatial correlation analysis shows a distinct negative correlation between urbanization and ESH. The degree of negative correlation shows an upward trend with the processes of urban sprawl. The analysis results reveal the impact of urbanization on urban ESH and provide useful information for planners and environment managers to take measures to improve the health conditions of urban ecosystems.
Ecological vulnerability, as an important evaluation method reflecting regional ecological status and the degree of stability, is the key content in global change and sustainable development. Most studies mainly focus on changes of ecological vulnerability concerning the temporal trend, but rarely take arid and semi-arid areas into consideration to explore the spatial heterogeneity of the ecological vulnerability index (EVI) there. In this study, we selected the Ningxia Hui Autonomous Region on the Loess Plateau of China, a typical arid and semi-arid area, as a case to investigate the spatial heterogeneity of the EVI every five years, from 1990 to 2015. Based on remote sensing data, meteorological data, and economic statistical data, this study first evaluated the temporal‒spatial change of ecological vulnerability in the study area by Geo-information Tupu. Further, we explored the spatial heterogeneity of the ecological vulnerability using Getis-Ord Gi*. Results show that: (1) the regions with high ecological vulnerability are mainly concentrated in the north of the study area, which has high levels of economic growth, while the regions with low ecological vulnerability are mainly distributed in the relatively poor regions in the south of the study area. (2) From 1990 to 2015, ecological vulnerability showed an increasing trend in the study area. Additionally, there is significant transformation between different grades of the EVI, where the area of transformation between a slight vulnerability level and a light vulnerability level accounts for 41.56% of the transformation area. (3) Hot-spot areas of the EVI are mainly concentrated in the north of the study area, and cold-spot areas are mainly concentrated in the center and south of the study area. Spatial heterogeneity of ecological vulnerability is significant in the central and southern areas but insignificant in the north of the study area. (4) The grassland area is the main driving factor of the change in ecological vulnerability, which is also affected by both arid and semi-arid climates and ecological projects. This study can provide theoretical references for sustainable development to present feasible suggestions on protection measures and management modes in arid and semi-arid areas.