Background: We explored the spatio-temporal characteristics of urban heat island (UHI) effect on cardiovascular diseases (CVDs). Methods: The land surface temperatures (LST) were retrieved from four Landsat remote-sensing images’ data, the temperature data from 95 meteorological stations, and analysis data on CVDs mortality. Based on these data, landscape pattern indexes were used to analyze the pattern-process-function and the mechanism. Results: During 1984–2017, the effects of UHI on CVDs increased, thereby increased the mortality by 28.8%. The affected areas gradually expand from the central area of the city and undergo three evolution stages; the highly affected areas are mainly distributed in central and southern regions, and patches increase in number. The areas and ratio of high-level patches also show an upward tendency, increasing dominance in the overall landscape. Patches of the overall landscape become more complicated in shape, whereas those of high-level ones become less complicated. Concentration degree of the overall landscape decreases gradually with the types of landscapes patches increasing, reaching a rather even space distribution. Conclusion: Increased temperatures exacerbated by UHI lead to increased CVD mortality. As cities expand, the effects of UHI on CVDs increase in terms of both intensity and areas, with the overall landscape in uneven distribution, high-level affected areas in point distribution, and low-level ones in large-area concentration.

It is of great significance to analyze and predict the evolution characteristics and trade-off synergies of ecosystem services in rapidly urbanized areas for improving the function of regional ecological restoration. Based on the future land use simulation and the method of equivalent scale estimation, this paper analyzed and predicted the characteristics of ecosystem service value (ESV) from 1990 to 2030, and combined with the correlation index, analyzed the trade-off synergy relationship between ecosystem services in 2030. The results showed that: (1) From 1990 to 2030, ESV in the study area fluctuated and decreased slightly. From 1990 to 2000, ESV decreased significantly, and gradually increased after 2000. As far as ESV is concerned, its regulation service function is the strongest, especially hydrological regulation, accounting for 54.51%. Agricultural production and the transfer in and out of waterspace ecological land are the key factors for the improvement and deterioration of ESV. (2) The spatial pattern of ESV in Zhengzhou-Kaifeng-Port area is higher in the north and lower in the west and the middle and east. Under the scenario of urban development, the decline was the most obvious, while under the scenario of cultivated land protection, ESV tended to be stable in most areas, and the bare land in the middle of the Yellow River continued to turn to agricultural production land, which promoted the increase of ESV. During the study period, the center of gravity of ESV was always located at the junction of Dameng Town and Guandu Town in Zhongmou County, and continued to shift to the northeast. (3) The synergistic relationship of ecosystem services is obvious, and the trade-off relationship is less and mainly exists between regulation and support services. This study is of great significance to accurately grasp the trade-off and synergy relationship of ecosystem service value under rapid urban expansion, and can provide a scientific basis for ecological restoration in rapid urbanization areas represented by Zhengzhou-Kaifeng-Port.

INTRODUCTION: Due to rapid economic development and continuous human activities, land use changes in the suburbs of metropolitan areas are drastic, which in turn affects the balance of ecosystem functions. Analyzing and predicting the ecological service value characteristics and trade-offs in rapidly urbanizing regions is of great significance for promoting high-quality regional development.AIM: This study attempts to reveal the trade-off and synergistic characteristics between the internal values of ecosystem services in suburban metropolitan areas under the influence of rapid urbanization.METHODS: Based on the patch-generating land use simulation (PLUS) model, simulated the land use changes in Xinzheng City under multiple scenarios in 2030, combined with methods such as equivalent factor method and spatial autocorrelation analysis，estimating, and predicting the ecosystem service value and its trade-off synergy relationship in Xinzheng City from 1980 to 2030.RESULTS: The value of ecosystem services in Xinzheng City continues to decline, hydrological regulation and soil conservation are the most important ecosystem service functions, under the scenario of farmland protection, ESV shows a stable growth trend. The synergistic relationship between various functions of ESV is significant, the Shizu Mountain National Forest Park, Shuangji River and other high agglomeration areas, as well as the Airport Economic Zone and Nanlonghu Town and other low agglomeration areas, all show a synergistic relationship, with only a portion of the southern side of the main urban area of Xinzheng showing a balancing relationship.CONCLUSIONS: Our findings can scientifically identify the environmental advantages of ecological sustainable development in Xinzheng City, and transform them into development advantages, providing provide strong technical support for the spatial ecological restoration and ecological security pattern construction of metropolitan suburbs.