Thermal Comfort Maps to estimate the impact of urban greening on the outdoor human comfort

Outdoor human comfort is an important factor in the evaluation of the liveability of a city as well as for promoting people’s health and well-being. In hot arid climates in particular, urban planning and design can considerably impact the day-to-day thermal comfort of the pedestrians, for better or for worse. Strategies to reduce thermal discomfort include shading structures, water bodies, and the promotion of natural ventilation – and most significantly, green areas. Trees have a major impact on the pedestrians in the built environment as they not only provide shading but also improve the microclimate in urban areas, thereby reducing the time during which discomfort is felt. The objective of this paper is to present a new methodology for dynamically quantifying the impact of different plants in urban areas on outdoor human comfort, through 3D urban energy modelling. The proposed methodology makes use of an urban energy modelling tool, providing a comprehensive view of the city energy fluxes, with a focus on the impact of trees on the human thermal comfort. Outdoor human comfort is assessed using the Index of Thermal Stress for the campus of the Swiss International Scientific School of Dubai (UAE), where “Thermal Comfort Maps” are designed to quantify the pedestrian thermal sensation and its variation in time and space. Additionally, the energy fluxes impinging on the urban pedestrians are quantified, dynamically, in hourly time step, providing an important instrument to understand their thermal stress, and the environmental factors affecting it. Based on the simulations, thanks to native greening, a significant improvement in outdoor comfort conditions was achieved in the campus, reducing the “warm/hot” and “very hot” thermal sensations from 1,291 h (on average over the entire campus) to less than 300 h by planting Ghaf and Acacia trees.     

Analyzing spatial inequalities in use and experience of urban green spaces

As cities become more densely populated, urban green spaces (UGS) are increasingly important due to the environmental and social benefits they provide. Cities are confronted with the challenge of equitable supply of high-quality urban green that meets the demand of residents. This is particularly relevant in lower-income neighborhoods, which tend to suffer from the lowest supply of (high quality) UGS. In this paper, we perform spatial analysis on the responses of an online user survey to explore how UGS frequency of use, choice, and satisfaction differ by use pattern and place of residence in the Brussels Capital Region. Additionally, we identify the “push-pull” factors of individual UGS by identifying the desirable (pull) and undesirable (push) qualities that may attract or repel the use of a UGS. We find that use pattern is related to choice and experience of UGS. Compared to people who use UGS for social purposes, those who use UGS for nature-oriented reasons more often choose to visit UGS that are substantially farther from their home but are more often satisfied with the UGS they use. Our findings also show that respondents living in areas with higher proportions of disadvantaged groups tend to travel substantially farther to reach their UGS and are more often dissatisfied with the UGS they visit. Finally, our push-pull analysis indicates that characteristics that are important to nature-oriented users, such as quietness and calmness, are often more negatively experienced in dense city center UGS. Our research thus demonstrates the need to bring more green, particularly green that elicits a feeling of “naturalness”, to areas of the city where low green space quality and quantity overlap with areas inhabited by vulnerable populations.     

Effect of green infrastructures supported by adaptative solar shading systems on livability in open spaces

Lack of thermal comfort in the existing building stock in many warm summer climates and the COVID-19 pandemic have increased residents' temporary occupation of urban open spaces. However, climate change and other effects such as urban heat islands are also negatively affecting the livability of these spaces. Therefore, strategies are needed to improve the thermal conditions in these areas. In this context, the research designs, simulates and assesses an urban green infrastructure supported by an adaptative solar shading system. For this purpose, a public square to be renovated in Seville (Spain) is chosen. After an analysis of the current situation, more vegetation is added. However, trees are not planted fully grown, so their cover is not enough in the short term and an artificial system that protects from the sun by casting shade and that adapts to both their growth and the seasons is included. The urban space is characterized by on-site measurements, proposing four (initial, intermediates and final) scenarios using computational fluid dynamics simulations in an holistic microclimate modelling system. In turn, changes in thermal comfort are analyzed using the COMFA model. Results show that the air and surface temperature are decreased, reducing the number of hours in discomfort by 21% thanks to incorporating the green structure and by 30% due to the vegetation. It can be concluded that the use of these temporary urban prostheses enables urban spaces regenerated with vegetation to be enjoyed without waiting 20 or 30 years for the trees to mature, encouraging people to spend more time outdoors from the start of the intervention.     

The role of urban green spaces in care facilities for elderly people across European cities

Urban green spaces (UGS) are increasingly acknowledged for their importance for the well-being of urban populations. However, studies are lacking the consideration of the demand and use of UGS by different population groups and connecting UGS with social infrastructure. In an era of worldwide urbanization and ageing, this European study sheds light on the role of UGS for care facilities for elderly. 126 care facilities from 17 cities in Austria, Germany, Norway, Poland, Romania and Slovenia took part in an online survey. Administrations of care facilities gave insights on the (1) importance of gardens related to care facilities for the quality of life for the seniors, (2) importance of UGS outside of care facilities for the quality of life for the seniors and (3) the consideration of natural and age-friendly designs and management of ecosystem disservices of UGS. The results emphasize not only the importance of UGS for the quality of life of seniors residing in care facilities, but also for the staff and visitors. UGS contribute to physical activities, recreation, and social interactions. The study found that in particular facilities with an own garden are highly aware of the benefits UGS provide. The study holds important lessons for UGS planning, management and design not only to focus on the quantitative supply of UGS, but also to consider age-sensitive amenities in and access to UGS of high quality for seniors.     

Economic development and natural amenity: An econometric analysis of urban green spaces in China

Rapid urbanization and spontaneous economic development has brought about profound changes in urban landscapes throughout the world. The task of managing transforming urban landscapes, particularly urban green spaces, so as to provide sufficient natural amenity for increasing urban populations, is one of the critical challenges facing policy makers. However, little empirical evidence exists about the evolving path of urban green spaces along with economic development and urbanization. This study attempts to fill in this knowledge gap through an econometric analysis of panel data across 285 Chinese cities during a period of rapid urbanization and economic growth (2001–2010). The results point to the existence of an N-shaped environmental Kuznets curve (EKC) for an important aspect of environmental quality: urban green spaces. Urban green space coverage increases at the initial stage of economic development, and then it starts to decrease as GDP per capita exceeds RMB50,855 and then increases again at a high GDP per capita level (RMB107,558). Large elasticity (>1) is expected as GDP per capita grows to a higher level (beyond RMB128,095). By the end of 2010, 30% of Chinese cities are still located on the downward-sloping path and only four cities have attained elasticities greater than one. The findings present a challenging and pressing call for policy makers to effectively manage the tradeoffs between continuous economic development and better natural amenities.     

Effects of vegetation,urban density,building height,and atmospheric conditions on local temperatures and thermal comfort

This paper shows the effects of several variables, which co-cause the Urban Heat Island effect on temperature distribution and outdoor thermal comfort (by using the Predicted Mean Vote, PMV) on dense urban environments. The study was conducted by means of a three-dimensional microclimate model, ENVI-met 3.1, which forecasts the microclimatic changes within urban environments. The effects of building density (% of built area) and canyon effect (building height) on potential temperature, mean radiant temperature, and Predicted Mean Vote distribution are quantified. The influence of several types of green areas (vegetation on the ground and on roofs) on temperature mitigation and on comfort improvements is investigated for different atmospheric conditions and latitudes in a Mediterranean climate. The research quantifies the effects of the variables investigated on temperature distributions and in determining outdoor comfort conditions. Vegetation on the ground and on roofs mitigates summer temperatures, decreases the indoor cooling load demand, and improves outdoor comfort. The results of the study demonstrate that density and height of buildings in a city area influence potential temperature, mean radiant temperature, and Predicted Mean Vote distribution; for most of the cases examined higher density causes higher temperatures and with taller buildings vegetation has higher cooling effects. Considering the cooling effect of vegetation, a difference can be noticed depending on the amount of green areas and vegetation type. The results of this study show also that vegetation is more effective with higher temperatures and lower relative humidity values in mitigating potential temperatures, mean radiant temperatures, and PMV and in decreasing the cooling load demand.     

Evaluating the risk of accessing green spaces in COVID-19 pandemic: A model for public urban green spaces (PUGS) in London

The pandemic caused by SARS-CoV-2 (COVID-19) at the beginning of 2020 has restricted the human population indoor with some allowance for recreation in green spaces for social interaction and daily exercise. Understanding and measuring the risk of COVID-19 infection during public urban green spaces (PUGS) visits is essential to reduce the spread of the virus and improve well-being. This study builds a data-fused risk assessment model to evaluate the risk of visiting the PUGS in London. Three parameters are used for risk evaluation: the number of new cases at the middle-layer super output area (MSOA) level, the accessibility of each public green space and the Indices of Multiple Deprivation at the lower-layer super output area (LSOA) level. The model assesses 1357 PUGS and identifies the risk in three levels, high, medium and low, according to the results of a two-step clustering analysis. The spatial variability of risk across the city is demonstrated in the evaluation. The evaluation of risk can provide a better metric to the decision-making at both the individual level, on deciding which green space to visit, and the borough level, on how to implement restricting measures on green space access.     

The role of green spaces and their management in a child-friendly urban village

Environmental child-friendliness is affected by how built environments and green spaces are planned and designed, but also by their ongoing management, including both development and maintenance. This study examined children’s perspectives on their local environments with focus on green spaces and their management in an urban village. Five groups totalling 16 children aged 10–11 were interviewed through child-led walks. Both the qualities of the village as a whole and of specific places within it added to the child-friendliness of the local environment. The children showed planned and managed spaces including playgrounds and parks, and unmanaged places such as abandoned gardens. They found many qualities in multifunctional planned places with a varied, rich content. In unmanaged areas the lack of management was seen as positive for exploration, play possibilities and for the place to be children’s own. The findings suggest that children’s perspectives can play an important role not only in planning and design, but also in the ongoing process of landscape management, including the provision of more variation in local green spaces.     

Classification of institutional barriers affecting the availability,accessibility and attractiveness of urban green spaces

The main goal of this article is to identify and classify institutional barriers which prevent the use of urban green spaces (UGS) at three levels: availability (whether a UGS exists), accessibility (whether it is physically and psychologically accessible, e.g., not fenced off), and attractiveness (whether it is attractive enough for potential users to visit). We reviewed the impacts on UGS provision exerted by different actors (individuals, formal and informal groups, community councils, city authorities, national governmental and non-governmental organizations), along with the relevant institutional foundations of those impacts. As a result, we identified and classified the different barriers for which these actors are responsible in the case of fifteen UGS types in our case study city, Lodz (Łódź) in Poland. The main barriers at different levels concern conflicting interests, physical barriers (private green spaces), and the lack of funds, together with legal and governmental failures (public green spaces). These barriers result from the different actors’ mandates or lack thereof. Our analysis has implications for the operationalization of UGS availability, accessibility and attractiveness, and, in particular, for mapping UGS and setting the relevant indicators and thresholds for UGS availability, accessibility and attractiveness.     

Wealth and land use drive the distribution of urban green space in the tropical coastal city of Haikou,China

Urban green spaces (UGSs) provide a plethora of ecosystem services that benefit humans and wildlife within cities. UGS both promotes and is affected by overall urban ecological health, which can be measured by a wide range of indices. In this study, we investigated the distribution patterns and drivers of UGS within the tropical coastal city of Haikou, Hainan, China over the past decade using a combination of remote sensing data and field work. We interpreted Google earth images from 2010 and 2020 to determine the land cover of UGS within Urban Functional Units (UFUs). We collected socioeconomic variables to test if wealth, site age, and land use determine the proportion of UGS in the city. We found that the proportion of UGS in parks was the highest among all UFUs in 2010 and 2020. In general, UGS increased with maintenance frequency and housing price, which are proxies for the luxury effect. However, land use also played a role in UGS distribution across UFUs, especially in transportation areas, recreation and leisure districts, and residential districts. Haikou is similar to other cities in showing a positive luxury effect on the distribution of UGS. Our results highlight the key roles that parks, colleges and universities, and research institute areas have played in maintaining stable green space within Haikou over the past decade. We suggest that relatively recently implemented governmental programs to increase green space elsewhere in the city may not yet have achieved success within the time span that we analyzed.     

Effects of vegetation structure and environmental characteristics on pollinator diversity in urban green spaces

With accelerating urbanization, insect pollinators in urban ecosystems face challenges such as reduced pollen sources, habitat fragmentation, and damage to the nesting environment. Urban green spaces (UGS) are essential for the stability of pollinator communities. However, little is known about the relationship between vertical layer heterogeneity and horizontal layer complexity of vegetation structure in UGS and pollinator communities. The present study aimed to assess how vegetation structure and environmental characteristics shape the insect pollinator community in UGS. To this end, this study was conducted with seven typical vegetation types which were selected according to the biotope mapping classification system (BMCS) in the ring parks around Hefei City, in Anhui province, China. A total of 11,401 pollinators belonging to 6 orders and 34 families were identified during the eight-month survey. Among the seven habitats under the BMCS, mainly successional short-cut shrub and partly open green space, trees two- or multi-layered broad-leaved mixed forest and partly closed green space, and mainly successional tall grass and partly open green space were identified as high-quality insect pollinator habitats. According to the results of the generalized linear regression, the explanatory power of the four best-fitting generalised linear models is relatively high (over 77%). In four optimal models, the effect of vegetation structure on pollinator community was greater than that of environmental characteristics. The redundancy discriminant analysis showed that the flowering abundance of nectar plants, herb richness, and shrub coverage rate were the three most important factors influencing insect pollinator communities, with a cumulative explanatory power of up to 78.8%. Pollinator abundance was positively influenced by spontaneous herbs and low-intensity management. However, high-intensity management, low diversity of plants, low nectar plant richness, ignoring seasonal nectar plant configuration, and dense tree distribution could limit pollinator reproduction and population growth. These results reflect the status of insect pollinator community in UGS in Hefei city and present a possible direction for improving urban green habitats and plant configurations.     

The impact of urban green infrastructure as a sustainable approach towards tropical micro-climatic changes and human thermal comfort

Green infrastructures such as living walls are technological solutions to replace the declined greenery at urbanized environment and also reliable applications for thermal regulation in buildings through insulation effect and escalates the energy use efficiency. Thermal comfort and local climate are spatiotemporally variable. The existing research gap should be addressed by evaluating the performance of vertical green walls in tropical condition. In this study, thermal performance, relative humidity (RH) and CO₂ concentration were quantified for basic three types of green infrastructures; such as (T₁) living walls, (T₂) indirect green façades and (T₃) direct green façades located in Colombo metropolitan in Sri Lanka. An in-situ experimental study was conducted considering temperatures at 1 m and 0.1 m distance in front of the green walls, inside the foliage, air gap and external wall surface comparatively to adjacent bare wall control. Three case studies per green infrastructure within Colombo metropolitan area were purposively selected. Simultaneously, RH and CO₂ concentration at 0.1 m in front of the green and bare walls were measured for the performance quantification. The internal thermal comfort simulation and occupants’ satisfaction questionnaire survey was executed to assess the green infrastructure performances. The study revealed that vertical greenery systems were highly effective on external wall surface temperature reductions at 1100 h–1500 h time zones. T₁ and T₂ accounted for superior temperature reduction in the range of 1.61 °C–1.72 °C through the façade relative to the distance than T₃. Maximum temperature reduction compared to the bare wall control was obtained for the T₁ (0.28 °C–8.0 °C) followed by T₂ (1.34 °C–7.86 °C) and T₃ (1.34 °C–6.64 °C). Averaged RH increment (1.6%–1.81%) and CO₂ reduction (0.63%) occurred near green walls at day time compared to control. An average 28 °C simulated indoor temperature circumstantiate the indoor thermal comfort. 58% and 89.5% occupants’ were satisfied with thermal and visual comfort respectively, thus emphasizing façade greening as a sustainable approach on micro climatic changes and human thermal comfort.     

Bioculturally valuable but not necessarily worth the price: Integrating different dimensions of value of urban green spaces

The social processes that took place in the past left a mark not only on cultural heritage but also on ecosystems and biodiversity, which is now depicted in the concept of biocultural diversity. The related “biocultural value” represents yet another dimension of the value of urban green spaces which we attempt to integrate into monetary valuation with the use of hedonic pricing. We compare the impacts of different green spaces on property prices in Łódź, Poland, differentiating green spaces based on their biocultural value. Furthermore, we use quantile regression and analyze the heterogeneity of estimates according to the price of the apartment. Our study indicates that while there is a general desire to live close to the green space, biocultural value does not translate into any positive impact on property prices.     

Sniff the urban park: Unveiling odor features and landscape effect on smellscape in Guangzhou,China

Smellscape, as the sense of smell cross space, has a huge impact on human behavior, attitudes and health. However, so far it has rarely been addressed and measured in both landscape practice and theories. The present case study refined the quantitative smellwalk method to examine the spatial and temporal features of urban park smellscape. The effects of landscape patterns on smellscape were further unraveled combining with remote sensing techniques and field surveys. The results indicated that: (i) human activities and nature odors dominated the urban park odor environments, (ii) the temporal variation of the urban park smellscape was mainly driven by human activities, (iii) the different site types of urban park exerted a significant impact on the composition of the smellscape, and (iv) the landscape pattern characteristics of forest, shrubs, grass, water, buildings and roads had significant effects on different types of odors. This study poses a first systematic exploration of various odors in urban green environments and offers novel insights into the design of smellscape via unveiling spatial-temporal odor distribution patterns.     

Assessing the impacts of urbanization-associated green space on urban land surface temperature: A case study of Dalian,China

Taking Dalian City as the study area, the spatial distribution of urban green space and land surface temperature (LST), as well as their evolution in 1999, 2007 and 2013, were obtained through remote sensing (RS) interpretation and inversion. Landsat ETM and SPOT data were used for this purpose. By combining the temperature and vegetation index models (TVX), the effects of urban green space reduction on the thermal environment during city development were evaluated. The results show the following. (1) During 1999–2013, 88.1 km² of urban green space was converted to other land uses, accounting for a 29.4% reduction in urban green space in the study area. (2) During the study period, the LST in this area increased by +8.455 K. The evolution of the regional thermal landscape can be characterized by increases in the LST, greater complexity of the thermal landscape structure, increase and aggregation of high-temperature areas, and reduction and fragmentation of low-temperature areas. (3) During the process of urbanization, urban green space with low land-surface temperature was converted to other land use types with high land-surface temperature. When development occurred at the price of urban green space, negative effects on the regional thermal environment were observed.     

Responses of four hornet species to levels of urban greenness in Nagoya city,Japan: Implications for ecosystem disservices of urban green spaces

Although there is a common trend towards increasing green space in modern cities, urban green spaces provide not only ecosystem services but also disservices for urban dwellers. However, the relationship between urban greenness and ecosystem disservices has been poorly examined. We aimed to understand the effect of greenness level on the abundance and species composition of hornets – critical pests in Japan and to identify the best spatial scale for estimating their abundance with reference to greenness levels. We used a dataset that contained eight years of abundance data for four hornet species at 11 sites in Nagoya city. The levels of greenness around the hornet sampling points were measured using averages from the Normalized Difference Vegetation Index (NDVI) with radiuses of 0.1–10.0 km. We analysed the relationship between abundance and species composition of hornets and NDVI at different spatial scales using generalized linear mixed models. Higher NDVI values positively affected the abundance of all the hornet species except Vespa analis. The abundances were estimated most effectively using the NDVI average with a 1–2 km radius for all species. The species composition of hornets drastically changed along the gradient of NDVI values; V. mandarinia was dominant in greener areas (over 0.2–0.3 NDVI average with a 2 km radius) and V. analis in less green areas (below 0.2–0.3 NDVI average). Our study showed that the abundance and species composition of hornets were both strongly associated with the level of urban greenness. This suggests that increases in the greenness of urban areas can increase hornet abundance and alter the species composition of hornets; a more aggressive species, V. mandarinia, may also increase in urban areas, although V. analis is currently the most critical species according to regional consultants. Balancing ecosystem services and disservices has become crucial for the planning and management of green spaces, particularly when urban green space increases. We also demonstrate how human tolerance towards wildlife may have to be improved in order to live in greener environment where wildlife can be expected.     

Spatial patterns and drivers of plant diversity in the tropical city of Sanya,China

Drivers of patterns in plant diversity remain poorly understood in tropical cities. Therefore, we investigated diversity within the tropical city of Sanya in Hainan Province of southern China by sampling one to three plots within 154 urban functional units (UFUs) based on six primary and 18 secondary UFUs. To measure diversity, we determined the number of vascular plants (species richness; SR) within each functional unit based on vegetation plots. We computed Faith's phylogenetic diversity (PD_Faith) using a large megatree of plant life. To assess the potential drivers of SR and PD_Faith, we performed multiple regressions using socioeconomic, biophysical, and vegetation management variables. The results showed significant differences in SR and PD_Faith among the six primary UFUs. PD_Faith of cultivated species was significantly higher than PD_Faith of spontaneous species in all UFUs except in the wasteland area. Management measures were better predictors of SR and PD_Faith than socioeconomic variables. The best predictor of SR and PD_Faith of spontaneous species was the management of the urban green space. Our results provide clear guidelines for improved management strategies in Sanya, especially by showing how spontaneous and/or cultivated plant diversity can be encouraged depending on environmental, ecological, and cultural needs. Our work also adds to the presently scarce literature on drivers of urban plant diversity in tropical cities worldwide.     

Comparison of avian diversity between urban parks adjacent to mountain and river in the largest megacity Guangzhou,South China

Urban parks can provide a resource for maintaining and increasing bird biodiversity. However, little research has been conducted to show the differences in bird community diversity between parks adjacent to mountains and rivers in the city center of highly urbanized areas. This study analysed whether the bird composition and species diversity differed between parks adjacent to Baiyun Mountain (hillside parks) and Pearl River (riverside parks) in Guangzhou, South China. From January 2018 to December 2020, 137927 birds representing 206 species were recorded. The results indicated that the number of species and individuals of birds were higher in hillside parks than in riverside parks in each season. The number of species and individuals was also higher in hillside parks than in riverside parks in different functional groups according to bird food type, residential type, and ecological type. The number of species shared by the two types of parks was 120. The unique birds' species number in hillside and riverside parks were 67 and 19, respectively. Bird diversity in terms of richness and Shannon index was higher significantly in hillside parks than in riverside parks in summer. Principal component analysis of environmental traits of 18 parks showed that plant traits in parks have relatively high and positive contribution. Correlation analysis indicated that bird diversity was positively affected by water area, the highest altitude, habitats diversity and tree evenness in park, while negatively regulated by building coverage around each park. The top 20 most abundant bird species accounted for 87.5% of the total birds in the study period. Nycticorax nycticorax, Urocissa erythroryncha and Podiceps ruficollis were observed more frequently in hillside parks, while Pycnonotus aurigaster, Passer montanus, Acridotheres cristatellus were observed more frequently in riverside parks. Principal coordinates analysis also indicated that bird communities significantly differed between hillside parks and riverside parks. In conclusion, our findings highlight the importance of conserving mountains and rivers as buffer zones for serious anthropogenic disturbance in the city center. We propose that the conservation of hillside parks is a priority strategy for enhancing urban birds biodiversity.     

Enhancing the thermal comfort on urban level in a desert area: Case study of Dubai,United Arab Emirates

The urbanisation of deserts in Dubai is one way in which this city can expand and explore its full potential. In this piece of research, a case study of the Dubai International Academic City was used as a basis from which to study the importance of planning and orientation of projects in open, unpopulated land. It demonstrates the various alternatives for project orientation relative to the sun and wind, its effects on temperature and wind readings and consequently on outdoor thermal comfort levels. ENVI-met was used to simulate various scenarios generated from the existing base case in both summer and winter. The orientation which best promoted and allowed for higher wind flow through the project was found to record the best outdoor predicted mean vote levels, approaching a neutral state. The findings of this research may be used for setting up regulations regarding the planning of desert areas in Dubai on the basis of early assessment of designs.     

Estimating urban green space production in the macroeconomy: From public goods to a profitable method of investment

Accompanied by long-term urbanization, the Chinese production of urban green space (UGS) is gradually transforming into a land operation strategy for local governments to maximize land lease revenue. This paper presents empirical research on different types of investment, urban space, and gross domestic product (GDP) with a simultaneous equations model (SEM) of econometrics to test the capital circulation and accumulation of UGS production in China. The regression results strongly support our hypothesis that UGS production contributes to GDP growth and that there is an economic feedback loop between them. One billion RMB of the government’s fixed-asset investments produces 0.899 km² UGS in the long term, and this UGS yields 1.749 billion RMB tertiary industry GDP in return. Thus, the total return rate in the representative economic chain of “fixed-asset investment-UGS-tertiary industry GDP” is greater than 174.9%. However, this percentage also reveals the weakness of providing rewards in maximizing land lease relative to urban industrial, traffic and residential spaces. We also estimate the lagged correlation coefficient with a rational distributed lag model, showing that the production of UGS has a longer-term and more profitable influence on tertiary industry GDP than on secondary industry GDP. The long-run effect of investment on UGS lasts for approximately five years in producing secondary industry GDP and more than ten years in producing tertiary industry GDP. A continuous increase in fixed-asset investments in UGS would achieve a balanced return rate (100%) and start to produce profits after the 4th year, according to the economic chain of ΔFAI-ΔUGS-ΔTGDP.