Park Green Space Research Articles

Scale Characteristics and Optimization of Park Green Space in Megacities Based on the Fractal Measurement Model: A Case Study of Beijing, Shanghai, Guangzhou, and Shenzhen

This paper applies fractal theory to research of green space in megacity parks due to the lack of a sufficient qualitative description of the scale structure of park green space, a quantifiable evaluation system, and operable planning methods in traditional studies. Taking Beijing, Shanghai, Guangzhou, and Shenzhen as examples, GIS spatial analysis technology and the Zipf model are used to calculate the fractal dimension (q), the goodness of fit (R2), and the degree of difference (C) to deeply interpret the connotation of indicators and conduct a comparative analysis between cities to reveal fractal characteristics and laws. The research results show that (1) the fractal dimension is related to the complexity of the park green space system; (2) the fractal dimension characterizes the hierarchical iteration of the park green space to a certain extent and reflects the internal order of the scale distribution; (3) the scale distribution of green space in megacity parks deviates from the ideal pyramid configuration; and (4) there are various factors affecting the scale structure of park green space, such as natural base conditions, urban spatial structure, and the continuation of historical genes working together. On this basis, a series of targeted optimization strategies are proposed.

Prosperity and Growth Are Mutually Beneficial-Landscape Design of Meihe Park in Zhengzhou Airport

In the context of modern urbanization and rapid urban expansion, large-scale urban green space is vacant, Driving the development of urban green space has become a new trend of urban development in China. This paper takes the landscape design of Meihe road Meihe belt green space Park in Xinzheng City of Henan Province as the research object. Through the design of “Prosperity and Growth Are Mutually Beneficial”, combining the theme with the concept of ecological design, and taking the change process of people’s healthy growth as the main line of the whole park green space development, we hope to present the public with a unique idea, reasonable and appropriate modern landscape planning method of urban suburban green space.

Soil labile organic carbon impacts C:N:P stoichiometry in urban park green spaces depending on vegetation types and time after planting

Soil nutrient stoichiometry, expressed as the ratios of carbon (C), nitrogen (N), phosphorus (P) in soil, determines the biogeochemical processes of elements in terrestrial ecosystems. Soil labile organic carbon (LOC) is that active component of SOC characterized by rapid turnover times, which links soil organic carbon (SOC) sequestration to C emission. Surprisingly, however, the linkage between soil C:N:P stoichiometry and soil LOC components remains unknown, especially in urban park green spaces. To fill this gap, the soils of dominant vegetation (deciduous forest, evergreen forest and lawn) at three different time after planting (5, 10, and 15 years) in three urban parks of Chengdu megacity were collected, and their soil C:N:P ratios and LOC components were analyzed. Results showed that soil C:N:P ratios were significantly influenced by the elapsed time since vegetation planting. The contents of LOC components (dissolved organic carbon (DOC), microbial biomass carbon (MBC), readily oxidizable carbon (ROC)) all decreased with the more time after planting and they were higher in the soils of deciduous and evergreen forests than lawn vegetation. Soil C:N:P ratios were significantly correlated with LOC components instead of soil TOC, suggesting a sensitive response of soil C:N:P stoichiometry to the dynamics of soil LOC components. Overall, different vegetation types and the time of respective plant-soil interactions regulate the dynamics of soil LOC components, thereby promoting the heterogeneity of soil C:N:P stoichiometry.

转型中工业城市的公园绿地社会公平性研究——以东莞市东城街道为例

作为城市重要的生态空间，公园绿地为城市提供环境基础及景观保障，其资源的合理分配是社会公平的重要体现。提出公园绿地社会公平性新的内涵，即无论个体所处的人居环境条件如何，其获得的城市公园绿地质量应该平等。工业城市向服务型、创新型城市的转变是中国城镇发展的典型趋势，研究其公园绿地的社会公平性为城市更新改造与公共资源分配提供重要的科学依据。以东莞市东城街道为例，构建社会-经济-自然复合人居指标体系与公园质量评价体系，基于可达性模型与Pearson相关性系数对公平性进行测度。结果表明：由于区域更新强度及顺序不同，研究区的绿地布局存在不公平现象，居民享受的公园质量与小区的自然、经济要素具有一定的关联。转型中的工业城市高质量公园聚集于风景资源优越的高端居住区，其他公园质量普遍不佳。工业园区以及旧城区为公园服务盲区的主要聚集地。;As an important ecological space in the city, the park green space provides the environmental foundation and landscape guarantee for the urbanization process. Moreover, the reasonable allocation of park green space is an important embodiment of social equity. Social equity emphasizes the rights and democratic values of residents and considers the fairness of use of parks by different social groups. This paper proposes a new connotation of social equity of park green space: no matter what the living environment is, the quality of urban park green space obtained by individuals should be equal. The transformation of industrial cities into service-oriented and innovative cities is a typical trend of urban development in China. The study on the social equity of park green space in the industrial city provides an important scientific basis for urban renewal and public resource allocation. Thus we build a social-economic-natural composite residential index system of community and an evaluation system of park quality. The quality of parks is evaluated in terms of the categories of parks, the proportion of forest land, the proportion of water, and the level of recreation facilities. The research uses network analysis to construct the accessibility model, while service coverage rate and service overlap rate are combined to measure the service level of parks in the study area. Based on the analysis of park quality and accessibility level, the research uses Pearson correlation coefficient to measure and analyze fairness, the service and layout problems of industrial city parks and their causes are discussed in combination with the economic development level of industrial city. Taking Dongcheng Street of Dongguan as an example, the results show that: (1) due to the varying intensity and progress of regional renewal, high-quality parks are mainly concentrated around the areas with excellent scenery resources, while other regions are generally of poor quality. (2) the laggard nature of park construction in the industrial region, old city reconstruction and the existence of undeveloped area and private garden make the blind area of park service accounting for 22.29% of the study area. (3) there exists the unfair phenomenon of green space service level in the research area. At present, the layout of urban park green space relies on the original mountain and water system, and the new urban area develops high-end residential areas by virtue of high-quality parks. Therefore, the overall quality of parks enjoyed by the community has a certain correlation with its natural and economic indexes. In the future, industrial cities should expand urban cultural connotation, develop the diversified park system, and improve the quality and distribution of parks. This study takes transitional industrial cities as the research area, comprehensively discusses the social equity of green space parks in combination with natural, economic and natural living environment elements. With the stratified random sampling method, taking the community as the basic research unit is better than the previous studies taking the streets and districts as the basic units, and the objective problems are more specifically exposed. Also, it is of practical significance to discuss the allocation of public resources from the perspective of park quality.

城市花粉致敏植物种类构成、分布与潜在危害评估——以深圳市为例

气传致敏花粉会引发过敏症，且可通过每年在花粉季的反复接触逐渐加重，危害人体健康，严重时甚至危害生命。花粉致敏植物在城市中被广泛引种栽培，导致城市花粉症患者数量激增。以深圳市为案例，基于建成区600个样地的实地调查数据，分析花粉致敏植物的种类构成与时空分布，通过构建花粉浓度及花粉致敏危害潜力计算公式，评估花粉致敏危害潜力及其分布特点。结果显示：①调查记录到深圳市建成区花粉致敏植物46科92属186种，其中外来种占43.37%，其中美洲、亚洲和大洋洲来源占国外外来种的81.00%。花粉致敏植物种数以公园绿地最多，达126种。植物花粉致敏等级以Ⅰ级为主，达154种。②花粉致敏植物的盛花期为春夏季，占全年累计开花种数的65.02%。最高峰出现在8月，开花种数达92种。 ③花粉浓度潜力最高值也出现在8月，占全年总值的12.13%。豆科和禾本科植物贡献比例较大，分别占乔木和草本总值的40.86%和64.13%。龙岗区花粉浓度潜力占比较高，占各季花粉量的26.06%-29.42%。④冬春两季各样地花粉致敏危害等级均不高，但夏秋季有些样地达到二级重度危害。罗湖区调查样地全年花粉致敏危害等级均较低，光明区在春夏秋季致敏危害等级皆较高。高危害等级样地主要出现在附属绿地及公园绿地。⑤花粉致敏植物防控措施情景模拟结果，去除主要花粉致敏植物种类比降低所有花粉致敏植物的花粉浓度潜力更有效。本研究为城市花粉致敏植物的管理、规划、养护和研究提供参考。;Airborne allergenic pollen can cause pollinosis and aggravate every year through repeated exposure in the pollen seasons, endangering human health and even life in severe cases. Allergenic pollen plants have been widely introduced and cultivated in cities, leading to a sharp increase in the number of urban pollinosis patients. In this study, based on the investigation data of 600 plots in the built-up area of Shenzhen as a case study, the species composition and the spatiotemporal distribution of allergenic pollen plants were analyzed, and the potential allergenic hazard with its distribution characteristics was evaluated by constructing calculation formulas of pollen concentration and pollen allergenic potential. The results showed that: ① In the built-up area of Shenzhen, a total of 186 species of allergenic pollen plants from 46 families and 92 genera were recorded. Among the allergenic pollen plant species, 43.37% were alien species, with 81.00% of them originated from America, Asia, and Oceania. The number of allergenic pollen plant species was highest in park green space, up to 126. Allergenic levels were mainly graded Ⅰ, covering 154 species. ② The peak bloom stages of allergenic pollen plants were spring and summer, with flowering species accounted for 65.02% of the annual total. The peak month appeared in August, concerning 92 flowering species. ③ August had the highest potential value of pollen concentrations, accounting for 12.13% of the annual year total. The contribution of Leguminosae and Poaceae were relatively high, respectively, accounting for 40.86% and 64.13% of the arbors and the herbs totals. The values in the Longgang District were relatively high in all seasons, reaching 26.06%-29.42% of respectively seasonal total. ④ The allergenic hazard levels in all plots were not high in winter and spring, but some plots reached second-level severe in summer and autumn. The hazard levels of investigated plots in the Luohu District were relatively low throughout the year. In contrast, those of investigated plots in the Guangming District were relatively high in spring, summer, and autumn. The high-hazard-level plots mainly appeared in the subsidiary green space and park green space. ⑤ Results of scenario-simulation for allergenic pollen plants prevention and control measures showed that the effect of removing major allergenic pollen plant species might be better than that of reducing the pollen concentrations of all allergenic pollen plant species. This study provides a reference for the management, planning, and maintenance of urban allergenic pollen plants, and the research and solution of urban pollen allergenic problems.

植被群落特征对城市生态系统服务的影响研究进展

生态空间（林地、灌木、草地、水体）所产生的生态系统服务极大的改善了人类的生存环境，在城市绿地破碎化日益严重、绿地质量逐渐降低、乡土植物逐渐减少、入侵风险逐渐加剧等生态背景下，如何维持稳定而持续增长的城市生态系统服务供给，一直困扰着当下从事城市生态学领域研究的学者和城市管理者。植被群落作为城市绿地系统的基本组成单元，在绿地破碎化趋势下，可作为研究内容来探讨城市生态系统服务维持或提升策略；植被群落泛指城市中常见的、具有明显边界的、按照一定分布规则的植物群落单元，既包括道路绿地、居住区绿地、公园绿地等，也包括城市郊野自然林地。但对植被群落生态功能的研究也多停留在对某一生态问题的简单相关性研究，缺乏系统性和整体性。从微观层面的植被群落角度，整合相关文献研究，介绍了受植被群落特征影响的6种典型城市生态系统服务，综述了植被群落特征对这6种城市生态系统服务的影响机理，对植被群落特征因子进行总结、归类，从树种特性、垂直结构、水平结构、其他4个角度构建了"植被群落特征因子对城市生态系统服务影响关系表"。最后面向典型生态系统服务提升提出了城市低质量植被群落地区的营建和更新原则，以期为今后城市园林部门、规划部门制定城市绿地系统规划提供基础性技术支撑。;The ecosystem services generated by ecological spaces (woodlands, shrubs, grasslands, and water bodies) have greatly improved the human living environment. In the context of increasing fragmentation of urban green spaces, decreasing quality of green spaces, diminishing native plants and increasing risk of invasion, how to maintain a stable and sustainable increase in the supply of urban ecosystem services has been troubling scholars and urban managers. As a basic component of urban green space systems, vegetation communities can be used as a research component to explore strategies for maintaining or enhancing urban ecosystem services in the context of green space fragmentation; vegetation communities refer to common urban plant community units with distinct boundaries and according to certain distribution rules, including both road green space, residential green space and park green space, as well as natural woodland in the urban countryside. while studies on the ecological functions of vegetation communities were mostly confined to simple correlation studies of a certain ecological problem, lacking in a systematic and holistic approach. This paper introduces six typical urban ecosystem services that are influenced by vegetation community characteristics from the perspective of urban vegetation communities at the micro level, integrating relevant literature studies. This is followed by an overview of the mechanisms by which vegetation community characteristics affect these six urban ecosystem services, and a summary and categorisation of vegetation community characteristics factors. A table of relationships between vegetation community characteristics and urban ecosystem services was then constructed from four perspectives:tree species characteristics, vertical structure, horizontal structure and others. Finally, the principles for the establishment and renewal of urban low-quality vegetation communities are proposed for the enhancement of typical ecosystem services, with the aim of providing basic technical support for urban landscape departments and planning departments in their future planning of urban green space systems.

Study on Diversity and Protection Countermeasures of Zhongshan Park in Wuhan City

Park green space is an important part of garden green space, concentrated expression of the diversity of urban plants. In order to explore the diversity of plants in the park, a typical site in Zhongshan Park in Wuhan was selected for this survey. The species importance, richness index, diversity index and evenness index were used to analyze the characteristics of plant diversity.There are a total of 184 plants of 114 genera and 64 families in Wuhan Zhongshan Park. Among them, there are 86 species of plants of 40 families and 64 genera, 60 species of plants of 26 families and 38 genera, and 26 species of herbs, 11 families and 15 genera.The richness was herb layer > tree layer > shrub layer.Pielou uniformity was herb layer > tree layer > shrub layer;Shannon-wiener diversity was herb layer > tree layer > shrub layer.Simpson diversity was herb layer > tree layer > shrub layer.The diversity of herbaceous plants in the park is high, and the index of shrub layer is generally low, with few species. Plants in the park grow well, some plants are not evenly distributed.

Research on Strategy of Urban Park Barrier-free Facilities Reconstruction from the Perspective of Micro-renewal——Take Huicheng District of Huizhou City as an Example

The design of barrier-free facilities is an important part of paying attention to the disadvantaged groups in urban park green space, and it is the concrete embodiment of whether the whole park landscape design follows the general design principle of "creating fair use". By investigating the status quo of accessibility facilities in 11 parks and green Spaces in Huicheng District of Huizhou City, according to the types of facilities and the characteristics of users, the problems in accessibility design are proposed by combining quantitative analysis with subjective analysis. Based on the concept of micro update and upgrading strategy is put forward, which meet the demand of vulnerable groups create the public landscape space of fair use, To explore new ways to improve the green space quality of Huizhou urban parks in the future.

Spatial accessibility of park green space in Huangpu District of Shanghai based on modified two-step floating catchment area method

Spatial accessibility of park green space in Huangpu District of Shanghai based on modified two-step floating catchment area method

Relationship study among soils physicochemical properties and bacterial communities in urban green space and promotion of its composition and network analysis

AbstractBacterial communities are closely related to soil physicochemical properties in urban green spaces, which also are important biological indicators in urban soil quality. However, there has been little basic research on soil bacterial composition and network analysis in different urban green space types, leading to a lack of micro‐understanding during urban green space management. Therefore, 30 soil sample sites from 0 to 40 cm were separately selected from two primary urban green space types (attached and park) in Beijing. We investigated how soil bacterial communities and networks respond to soil physicochemical properties by using high‐throughput 16S rDNA sequencing. Soil moisture content, organic matter (OM), total N (TN), available N, available K (AK), total Pb, and total Hg in park green space soils were significantly increased 1.49, 2.04, 1.78, 1.46, 1.20, 1.84, and 7.19 times relative to attached green space soils. A total of 2,238,221 sequences (440 bp) were acquired from urban green space soils. norank_c_Acidobacteria, Blastocatellaceae_Subgroup_4_, Gemmatimonadaceae, Anaerolineaceae, and Nitrosomonadaceae were the major bacterial families, and soil OM (36.6%, P = .01) and TN (34.6%, P = .01) were significantly (P < .01) positively correlated with bacterial communities at the family level in urban green soils. Through network analysis, we determined that Actinobacteria was the core microorganism in parks and attached green space soils, but taxonomic groups in park green space soils tended to be more modular and more closely connected. Therefore, we should pay more attention to promoting development of soil nutrients in urban green spaces, especially attached green spaces. Our results provide scientific guidance for urban green space ecological environmental management.

Exploring the equality of accessing urban green spaces: A comparative study of 341 Chinese cities

Despite multiple benefits of green space for urban residents, the investigations on equality of access to green space are scarce. Most focused on individual cities and the results were inconsistent due to the varying definitions, scales, and evaluation methods employed within each. This study intends to address this gap by developing two indexes based on the Gini Coefficient to compare the inequality of access to urban green spaces across all 341 prefecture-level cities of China. An urban green space equality index (UGSE) measures the distribution of overall urban vegetation within a city. A park green space equality index (PGSE) focuses on the equality level of public access to parks.The UGSE and PGSE at the national scale are 0.490 and 0.848. Strong disparities have been found in both UGSE and PGSE across the country using the local indicator of spatial autocorrelation (LISA). Regression analysis shows equality of green space is significantly related to GDP per capita, population density, and urban land area. Urban greening related policies are not significantly associated with equality, suggesting that a lack of concern might exist among Chinese cities for the spatial equality of urban green space implementation. These findings can help decision makers evaluate regional disparities in urban green space equality, thereby providing location-specific interventions for more inclusive and equal provisioning of urban green spaces.

How to Find Vacant Green Space in the Process of Urban Park Planning: Case Study in Ningbo (China).

Nature-based recreation in urban areas is essential for the well-being of citizens. Park green space (PGS) is a necessary urban infrastructure and a critical step of urban planning and policy-making. The existing research on PGS only focuses on service allocation problems existing in the current urban development, ignoring changes in residential communities accessibility. This research provides new ideas to evaluate PGS. Based on parks and residential communities’ data, we adopt an improved Gaussian-based two-step floating catchment area (2SFCA) method to evaluate PGS accessibility in Ningbo (China) and its matching with different levels of residential areas. We present a case study in Ningbo, and discuss its implications for PGS management. This study contains two elements: (a) Compare the current and initial PGS accessibility of each community to accurately identify the communities with PGS vacancies. (b) Analyze and discuss the association between community accessibility and residential house prices. Compare the PGS coverage ratios of communities at different levels to determine the equity of PGS planning in Ningbo. We found that the level of PGS allocation in the central area of Ningbo is high. Obviously, high-value clusters are formed in Sanjiangkou, Zhenhai New Town, Southern and Eastern Yinzhou. The accessibility level in the middle area of Yinzhou is low, and there are super high accessibility residential communities in the outer city area. There is an exact period of green space vacancy in the middle and the outer area. The residential areas with ultra-high accessibility did not configure PGS services at the beginning of their construction. There is no noticeable difference in PGS accessibility of residential communities of different levels at present, but 149 low- and middle-income residential communities lack green space service when the construction was completed. High-end residential communities have priority on enjoying park green space services. Our study suggests that PGS accessibility should be studied temporally and spatially for each residential community. The Ningbo government should strengthen the balanced construction of green space in parks and guarantee green space services for low-end residential communities to improve green space equity.

Proximity to Facilities and Its Association with the Health-Related Habits of Functionally Independent Older Adults.

The aim was to examine how proximity to facilities, as a component of community determinants, is associated with the health-related habits of functionally independent community-dwelling older adults. This was a cross-sectional study. Data were collected by face-to-face interviews. Participants were >65 years old, living in 15 municipalities of Gipuzkoa (Basque Country, Spain). Proximity to park-green spaces, cultural-sport centers, market-food stores, retirement associations, religious centers, primary care centers and hospitals was explored. Sociodemographic variables and health-related habits (diet, physical activity and self-perceived social life) were collected. Logistic regression models were performed. The sample comprised of 634 individuals (55% women; mean age: 74.8, SD 6.7 years). Older age (odds ratio-OR: 0.94, 95% CI: 0.91–0.97) was associated with lower physical activity, while being male (OR: 1.71, 95% CI: 1.08–2.68) and proximity to park-green spaces (OR: 1.64, 95% CI: 1.03–2.61) were related to more physical activity. Individuals with good self-perceived health (OR: 3.50, 95% CI: 1.82–6.74) and religious centers within walking distance (OR: 2.66, 95% CI: 1.40–5.04) had higher odds of a satisfactory social life. Encouraging the creation of park-green spaces and leisure centers near residential areas can assist in promoting physical activity and improving the social life of older adults.

Equity to Urban Parks for Elderly Residents: Perspectives of Balance between Supply and Demand.

As population ages, ensuring that the elderly get their due rights has become a common concern of scholars in many fields. However, as an important public service facility in daily life of elderly, the research on the equity of urban parks is mostly based on the evaluation of accessibility. The equity of the elderly's access to urban parks services has been rarely discussed from the perspective of supply and demand balance. In the context of the concept of spatial equity, we used urban parks in the main city of Harbin as a case study, the actual travel mode of the elderly was considered in the evaluation, adopted an Integrated Spatial Equity Evaluation (ISEE) framework, quantitative evaluation of the equity of different levels of urban park under multiple traffic modes. In this study, the results showed that under the three modes of travel, the degree of spatial equity was higher for non-motorized trips than for the other two modes. In terms of urban parks hierarchy, the spatial equity of urban parks at district level were much higher than those at the neighborhood level and street level. The inequity between supply and demand for urban park for elderly people was significant and varies between administrative districts. The empirical evidence in this research may provide references and suggestions for urban parks planning and decision-making. In cities where the scale of land use is basically stable, such as Harbin, we can start from the spatial configuration of park green space system and public transportation system to improve the efficiency of urban parks provision. Thereby promoting the construction and development of an “old age-friendly” society.

Evaluation of the winter landscape of the plant community of urban park green spaces based on the scenic beauty esitimation method in Yangzhou, China.

Plant landscapes are fundamental components of the green space of urban parks and are often dynamic, changing throughout the year. Winter is a season with poor plant landscape effects in urban park green spaces. However, plant community landscapes in the winter in urban park green spaces could be further optimized. Here, we conducted scenic beauty estimation (SBE) of the landscape factors in 29 winter plant communities in four typical urban parks in Yangzhou, China using partial correlation analysis and multiple linear regression. The standard SBE values of the 29 plant communities ranged from -0.981 to 1.209. Complex plant community landscapes with abundant plant species, beautiful plant community morphology and obvious seasonal changes generally received high scenic beauty scores. Six landscape factors, including the diversity of plant species, the proportion of evergreen tree species, the morphological characteristics of plants, the ground cover rate, the overall sense of harmony and the color composition, greatly influenced the scenic beauty of the plant landscape in the winter. Generally, the results of this study provide insight into how the plant community landscape in urban parks could be improved.

Spatial equity of park green space using KD2SFCA and web map API: A case study of zhengzhou, China

In our review of the research on PGS (park green space) spatial equity, little consideration has been given to the impacts of small spatial scales and measurement accuracy on spatial equity assessments. Based on the web map API open data platform (including location and navigation data, etc.), this study established a fine-scaled evaluation framework of spatial equity from the aspects of sensitivity to measurement and the urban micro-perspective. The framework was integrated within the KD2SFCA (kernel density two-step floating catchment area) method, which planners use to accurately locate areas of under or over supply of urban public facilities. Taking Zhengzhou as a case study, we identified 2494 residential areas and 106 PGSs to describe the spatial equity of residents accessing different PGS levels by four travel modes. The results showed that there were significant differences in spatial equity between different PGS levels. Of the three PGS levels, the overall spatial equity for district PGS was the highest, community PGS was second, and municipal PGS was the lowest. We also found that different travel modes had important impacts on PGS spatial equity. One interesting phenomenon was that when residents chose to walk to a higher level PGS, the percentages of the population with “no supply” increased; when residents chose bicycle and private car modes to reach higher level PGS, the percentages of the population with “weak supply” and “over supply” increased. In addition, it is worth noting that community PGS was originally established to meet the needs of residents for short-distance entertainment. However, we found that almost all residents in the study area were in the extreme states of “no supply” or “over supply” when they reached community PGS by walking. These results provide a scientific basis for more reasonable and equitable allocation of urban PGS and the optimization of transportation facilities. This work can also provide a more fine-scaled research perspective and improve the scientific evaluation system for studying urban infrastructure spatial equity.

Research on the Spatial-temporal Changes and Driving Forces of City Green Space in Kunming

To explore the spatial and temporal changes and driving forces of city green space in Kunming since 1950, and provide a reference for future city green space development planning. Through consulting a large number of documents, Kunming statistical yearbook and field investigation, the geospatial analysis method and comparative analysis method were used to analyze the spatial and temporal changes of the park green space above 5hm2 in the downtown area of Kunming, and its driving force was analyzed by qualitative analysis method. The results shows that (1) There are four development stages in the construction of city green space in the downtown of Kunming. (2) The city green space in Kunming city center> 5hm2 ranks in order as Chenggong District, Panlong District, Xishan District, Wuhua District, Guandu District. (3) There are four trends in the spatial distribution of city green space. (4) The driving force mainly includes geographical factors, economic factors, population factors, transportation factors, and policy factors. After the comprehensive effect of various aspects, the current city green space distribution pattern in Kunming is formed.

Selection and Application of Garden Plants in the Construction of Sponge City in Northwest China

Li, R. and Zhang, C., 2020. Selection and application of garden plants in the construction of sponge city in Northwest China. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 1139–1143. Coconut Creek (Florida), ISSN 0749-0208.Since the development of sponge city construction in my country, most of the research on sponge city construction has focused on the engineering level. The research on the selection and application of plants is relatively lagging, making it impossible to reasonably choose plants during the construction of sponge cities. The lack of “localization” of the design and the lack of systematic and targeted consideration and design of the plant landscape configuration have restricted the construction and development of the sponge city to some extent. The purpose of this article is to solve the problem of the selection and application of garden plants in the construction of sponge cities in the northwestern region. Through the literature review method, field survey method, and case comparison analysis method, the roof garden, residential area green space, road green space, and landscape in the sponge city in northwestern China Selection and arrangement of plants in green space and park green space. Finally, combined with the problem analysis, the principles of sponge city plant selection and allocation were put forward. At the same time, the sponge city plants that can be applied to the northwestern region were summarized based on the survey results and related literature reading. The research results show that the satisfaction of the open layout is 81.38%, and the satisfaction of the enclosed layout is 79.30%. The open layout is more popular in use. The selection and application of garden plants in Northwest China based on the construction function of sponge cities proposed in this paper has positive significance for sustainable urban development.

Temperature induces soil organic carbon mineralization in urban park green spaces, Chengdu, southwestern China: Effects of planting years and vegetation types

Green spaces in urban parks are an essential part of urban planning, not only meeting the environmental demands of urban dwellers but also absorbing greenhouse gases generated in urban regions. Mineralization of soil organic carbon (SOC) is one of the most important processes of C cycling, and links C sequestration and emission. However, few studies have been focused on SOC mineralization in urban parks, especially in scenarios involving rising temperature. Here, soils from different ages of deciduous forest (DT), evergreen forest (ET) and lawn (LN) were collected from the urban parks of Chengdu megacity. A soil incubation study (35 days) was conducted to examine SOC mineralization in three temperature regimes (15, 25, and 35 ℃), three vegetation types (DT, ET, and LN) and three vegetation ages (5, 10, and 15yr), making 27 treatments in total. Results demonstrate that increases in temperature stimulated the daily SOC mineralization rate, cumulative SOC mineralization, and mineralization intensity in the soils from urban green spaces, especially in soils under the 5-year-old plantings. Furthermore, results from principal component analysis (PCA) showed that the soil labile organic carbon (LOC) fraction, especially readily oxidizable carbon (ROC), soil enzyme activity and soil pH are the major factors influencing SOC mineralization. During the incubation, the average temperature sensitivity (Q10) of the SOC mineralization rate at 25−35 °C was higher than at 15−25 °C (P < 0.05), indicating that more C would release from urban green spaces under a warmer climate. However, over all planting ages, the average Q10 of SOC mineralization rate in lawn soils reduced by 1.87 %–4.04 % and 4.16 %–5.84 % relative to deciduous and evergreen forest soils, respectively. Overall, the SOC mineralization rate was ranked LN > ET > DT, while the Q10 of the SOC mineralization rate was ranked DT > ET > LN with increasing temperatures. Moreover, the older vegetation showed lower SOC mineralization rates and higher Q10 values. These findings imply that SOC stored in the soils under grass and young plantations are less susceptible to climate warming, although the mineralization rates are higher. By contrast, SOC in soils under trees is more susceptible to climate warming, but the mineralization rates are lower. Overall, the temperature change is more important for the SOC mineralization in forest soils and older plantation soils in urban green spaces.

Can forest city construction affect urban air quality? The evidence from the Beijing-Tianjin-Hebei urban agglomeration of China

The Beijing-Tianjin-Hebei (BTH) urban agglomeration is the most polluted area of smog in China. The latest studies have been focusing on the influencing factors on the BTH’s PM2.5 concentration in terms of industrial, social, and climatic conditions. However, the role of the urban forest system has not been thoroughly studied in air pollution control. This study focuses on the impact of forest city construction on BTH’s PM2.5 concentration. According to the theoretical framework of the STIRPAT model, we used the spatial Durbin model of bidirectional fixed effect to empirically test the correlation between the BTH’s PM2.5 concentration and the characteristic variables of forest cities. The research results show that improving urban green space, park green space, and investment of urban sanitation and environment facilities can reduce the PM2.5 concentration in the local and adjacent areas. This study proposes that the construction of forest cities should be further strengthened to alleviate urban air pollution in the BTH’s coordinated development and thus improve regional air quality.