Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China

Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.

Optimal depth of in-situ pressure-preserved coring in coal seams considering roadway excavation and drilling disturbance

Using pressure-preserved coring technique to determine in-situ gas content provides a more precise assessment of gas resource reserves and safeguard of mining safety in coal seams. How coring technique and depth affect the determination of gas content is unclear due to borehole zoning rupture caused by roadway excavation and drilling disturbance. To this end, a proposed coupling model of stress distribution and gas migration was simulated and validated by FLAC^(3D) and COMSOL Multiphysics considering superposition effects of roadway excavation and drilling disturbance. The findings indicate that the roadway surrounding rock displays distinct zoning features including stress relief zone, stress concentration zone that is composed of plastic zone, elastic zone, and original stress zone;and the broken situations depending on the borehole peeping are consistent with the corresponding simulation results.On this basis, this study proposes a set of drilling coring depth calculation and prediction model for the gas desorption affected area under engineering disturbance. Optimal depth of coring drilling is not only approach to the in-situ coal bulk, but also can get the balance of the drilling workload and cost controlling. According to the typical mine site geological conditions and the numerical simulation results in this study, if the roadway excavation time is ~1 year, it is recommended that the pressure-preserved coring depth should be greater than 17 m.

Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement

Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.

Examining the Spatiotemporal Dynamics and Determinants of Land Urbanization in Prefecture-level Cities,China

Examining the spatiotemporal dynamics and determinants of land urbanization is critical for promoting healthy urban development and the rational use of land resources.Based on the dataset consisting of land use change data and selected factors in 2010 and2020,this study used visual analysis to reveal the spatiotemporal dynamics of land urbanization across prefecture-level cities in China.Meanwhile,the driving forces underlying land urbanization were examined by using geographical detector technique.Following are the findings:1)we find that there exist notable spatial variances in land urbanization across prefecture-level cities.Currently,the differentiation in land urbanization between the northern and southern cities is more pronounced than that between the coastal and inland cities,or between the eastern and western cities.Prefecture-level cities located in central and western China have experienced the most rapid growth in land urbanization.Conversely,the growth rate in northeastern China is the lowest,while the velocity in eastern China remains relatively stable.By using spatial autocorrelation analysis,this study reveals that the land urbanization level in prefecture-level cities has significant spatial agglomeration.2)We further find that land urbanization in China is influenced by factors related to urban land supply and demand,and urban population growth,economic growth,land financial and political incentive have greater impact on land urbanization than other factors.3)We also find that the impacts of determinants on China’s land urbanization vary over time,the explanatory power of economic development increased,while the explanatory power of state forces declined.We argue that integrating the supply and demand factors of land urbanization can provide a more comprehensive understanding of the driving mechanisms underlying land urbanization in China and other transitional countries,and help decision-makers in these countries formulate more detailed and specific land urbanization policies.

Evolutionary characteristics and influencing factors of agricultural regional system in the Loess Plateau of China under rapid urbanization

The rapid expansion of cities seriously threatens the sustainable development of agriculture in China.Exploring the evolution law and influencing mechanism of agricultural regional system in the process of urbanization is of great significance for promoting sustainable development of agriculture in China.This paper takes the Loess Plateau(LP)as an example,and constructs a research framework to study the effect of urbanization on agricultural regional system through the lens of human-earth interaction,aiming at elucidating the evolutionary characteristics of agricultural regional system and revealing the impact law of urbanization.The results show that:(1)The growth trend of the evolution index of the agricultural regional system in the LP was significant,gradually evolving into a spatial pattern of"high in the north and south,low in the east and west".(2)The hot spot and sub-hot spot zones of the agricultural regional system evolution index in the LP were mainly distributed in the south and north,while the cold spot and sub-cold spot zones were primarily located in the center,east and west.(3)The levels of agricultural mechanization,agricultural land productivity,cropland area,and agricultural labor productivity were the main internal influencing factors of the agricultural regional system in the LP.The obstacle degree of agricultural mechanization level,cropland area,and the proportion of agricultural employees increased over time,while the obstacle degree of agricultural land productivity and grain yield capacity decreased.(4)The impact of population urbanization in the LP showed a spatial pattern of"inhibition in the southeast and promotion in the northwest",the impact of economic urbanization was dominated by inhibition,and the impact of land urbanization showed a spatial pattern of"promotion in the whole and inhibition in the local".This study provides ideas for the comprehensive research on the evolution and influencing factors of agricultural regional system,and offers practical references for achieving sustainable agricultural development in LP.

Anthropogenic nesting materials and reproductive performance of Chinese Bulbuls(Pycnonotus sinensis)along the urbanization gradient in Hangzhou,China

Urbanization induced by human activities presents both challenges and adaptive opportunities for wildlife.One notable impact of urban sprawl is the vast amount of waste it produces,which has discernible effects on wildlife.Interestingly,an emerging trend has been observed that birds are incorporating anthropogenic materials into their nests.However,the relationship between anthropogenic nesting materials(ANMs)and the reproductive performance of urban birds is unclear.In this study,we investigated the relationship between the incorporation of ANMs into nests and the reproductive performance of Chinese Bulbuls(Pycnonotus sinensis)by monitoring and collecting data on 136 breeding nests in Hangzhou,China.We gathered data on seven reproductive traits of Chinese Bulbuls,including laying date,incubation period,nestling period,clutch size,egg volume,hatching success rate,and fledging success rate.We then calculated the urbanization synthetic index as a measure of the level of urbanization and examined its relationship with the proportion and weight of ANMs.Through examination of nest components,we observed significant increase in the proportion and weight of ANMs with the urbanization synthetic index.Notably,we found a higher hatching success rate of Chinese Bulbuls with an increasing proportion of ANMs.However,the inclusion of ANMs in nests was not correlated with other reproductive traits of Chinese Bulbuls.Overall,the use of ANMs by Chinese Bulbuls is consistent with the adaptive hypothesis and the availability hypothesis.Further studies should use controlled experiments to investigate the impact of ANMs on avian reproductive success.

Impact of air pollution on urbanization:evidence at China’s city level

This paper investigates the effect and transmission mechanism of air pollution on urbanization based on data from China’s 107 cities during 2005–2018.In order to identify the impact of air pollution on China’s urbanization,we utilized night light data to represent the level of urbanization and used temperature inversion as an instrumental variable to mitigate endogeneity within the two-stage least squares framework.The results suggest that air pollution significantly slowed China’s urbanization process with economic growth acting as the transmission mechanism.The heterogeneity analyses revealed that air pollution had a greater negative impact on urbanization in northern regions than that in southern regions,and a greater negative impact in resource-oriented cities than that in non-resource-based cities.We also find that air pollution was to the detriment of urbanization in larger cities,which have more than 3 million residents,while it did not have a significant impact on Type II large cities,which have fewer than 3 million residents.

Research on the Digital Economy's Impact on China's Economic Growth:Based on the Variations in Urbanization Levels Across China's Eastern,Central,and Western Regions and Sectoral Heterogeneity

This paper uses inter-provincial panel data from 2011 to 2017,a linear regression model,and a threshold model to conduct empirical analyses of the impact of the digital economy on China's overall economic growth and the three main sectors of industry.The paper then investigates the impact and effects the digital economy has had on the economic growth of the three main sectors of industry in China's eastern,central,and western regions.Finally,the paper investigates the most significant differences among the various regions and the threshold effects of urbanization levels on the relationship between the digital economy and economic growth.The findings indicate a significantly positive correlation between the digital economy and regional economic growth.Moreover,geographical factors notably influence this correlation.The digital economy exerts a positive effect on all sectors of industry.It may not substantially impact industrial development in regions with highly developed infrastructure.Regarding the other regions,the digital economy exhibits varying degrees of impact due to the differences in the specific indicators.The conclusion drawn by the threshold model is that the magnitude of the threshold effect correlates with geographic factors.No threshold effect was observed in the eastern region,while the threshold effect occurred in the central region when the urbanization levels for the provinces were below 0.6645.Similarly,the threshold effect was noted in the western region when the urbanization level was below 0.3931.Considering all of this,the study also offers policy recommendations that will help balance the regional development of digital economies,accelerate the digital transformation of traditional industries,enhance digital infrastructure construction,refine the formulation and implementation of data policy,and establish relevant incentive mechanisms.

The Implications of Urbanization Processes in Developed Countries for Africa

Urbanization is the inevitable path of national economic development,and the level of urbanization development in most African countries is still low.By analyzing five typical developed countries in the United States,Britain,France,Germany,and Japan,this paper discusses the promoting factors and problems of the rapid urbanization development in their specific years,as well as the experiences and lessons that Africa can learn,so as to prevent Africa from taking the detour in the urbanization process of Western developed countries and promote the balanced regional development of various African countries.

Local Climate Change Induced by Urbanization on a South China Sea Island

The South China Sea is a hotspot for regional climate research.Over the past 40 years,considerable improvement has been made in the development and utilization of the islands in the South China Sea,leading to a substantial change in the land-use of the islands.However,research on the impact of human development on the local climate of these islands is lacking.This study analyzed the characteristics of local climate changes on the islands in the South China Sea based on data from the Yongxing Island Observation Station and ERA5 re-analysis.Furthermore,the influence of urbanization on the local climate of the South China Sea islands was explored in this study.The findings revealed that the 10-year average temperature in Yongxing Island increased by approximately 1.11℃from 1961 to 2020,and the contribution of island development and urbanization to the local warming rate over 60 years was approximately 36.2%.The linear increasing trend of the annual hot days from 1961–2020 was approximately 14.84 days per decade.The diurnal temperature range exhibited an increasing trend of 0.05℃per decade,whereas the number of cold days decreased by 1.06days per decade.The rapid increase in construction on Yongxing Island from 2005 to 2021 led to a decrease in observed surface wind speed by 0.32 m s^(-1)per decade.Consequently,the number of days with strong winds decreased,whereas the number of days with weak winds increased.Additionally,relative humidity exhibited a rapid decline from 2001 to 2016 and then rebounded.The study also found substantial differences between the ERA5 re-analysis and observation data,particularly in wind speed and relative humidity,indicating that the use of re-analysis data for climate resource assessment and climate change evaluation on island areas may not be feasible.

Recent urbanization increases exposure to humid-heat extreme events over populated regions of China

目前对于高温的研究主要侧重于干热,针对湿热的研究相对较少,但它通常会造成更大的社会影响,尤其对人体健康的威胁.已有研究证实,当环境湿球温度超过35℃时,它会破坏人体正常生理代谢,进而威胁人体健康.本研究指出在过去四十年,中国区域日最高湿球温度几乎没有超过35℃,但部分地区日最高湿球温度超过了30℃,主要集中在中国的人口密集区,包括华东,华南和四川盆地等.进一步分析发现,中国区域近期的快速城市化加剧了极端湿热事件的社会影响,城市地区暴露于极端湿热事件的范围的增加速率明显大于其他地区,这也意味着快速城市化使得人口密集区暴露于极端湿热事件的风险明显增加.初步估算指出,自2000年以来,中国区域暴露于极端湿热事件的人口数以每年每天约3100人次的速率显著增加.

In-situ Urbanization Promoted by the Development of ＂Taobao Village＂

Starting from the important role of ＂Taobao village＂ in the economic development, the thesis analysed the subjective and objective reasons and promoting group and draw the general process of urbanization. It discussed the different characteristics of ＂Taobao village＂ in different economic areas and roles played in urbanizing. It also propounded some constructive suggestion to activate the industry, including strengthening industry supervision, adjusting development patterns, and emphasizing innovation. The paper consists of literature analysis, case analysis and comparative analysis to complement the demonstration.

Integration and Symbiosis between Traditional Folk Culture and Urban Space during Urbanization in China

By taking the residential environment change in Tai'an City of Shandong Province over the past 30 years for example, the paper had introduced characteristics of traditional residential culture and their influence on the urban residential spatial pattern, and explained the mutual effect and guidance between the establishment of new residential concepts and the extension of city context. It had pointed out that the government planning and development should be considered from historical and cultural perspective rather than economic perspective. Through the analysis of problems at each level, it had proposed that urban construction should pay attention to historical inheritance, and characteristic livable city construction should lay stress on the coordinated development between urban economy and historical culture.

Study on the Urbanization-based Restructuring of Urban Spaces in Meizhou City of China

By introducing the urbanization history of Meizhou City,major problems of its spatial structure were summarized as small scale of urban areas and incomplete hierarchical structure;poor cohesive force of central city,imbalanced regional spatial ratio;disorderly development of urban spaces;and fierce competition for space.Then spatial restructuring of Meizhou City was discussed from the following 3 perspectives:optimizing hierarchical structure of space,planning in advance to construct a central city with more than 1 million residents;establishing the traffic hub of Guangdong,Fujian and Jiangxi;improving spatial structure of industries.It was to enhance sustainable social and economic development of the local area,break the dualistic structure and realize the overall development of urban and rural areas,and also narrow the urban-rural gap.

Urbanization Level Analysis of Chongqing 1 Hour Economic Circle Based on AHP and GIS

With Chongqing 1 Hour Economic Center as an example, AHP was adopted to comprehensively analyze factors influencing the economic development of all districts and counties of Chongqing City, economic development scores were calculated and urbanization level of each district and county was comparatively analyzed. The results showed that the economic development level and the urbanization level of almost all districts and counties were not coordinated, then the reasons were briefly elaborated and corresponding countermeasures and suggestions were proposed.

Analysis of the Response and Driving Forces of Urban Landscape Pattern during Urbanization of Zhangjiagang City in China

By taking Zhangjiagang City as the research object, with the guidance of 3S (GIS, GPS and RS) and the theory of landscape ecology, based on the remote sensing images from 1991 to 2006, land use maps and social-economic statistical data, by combining with gradient analytical method, eight landscape pattern metrics had been selected to analyze the urbanization of Zhangjiagang City and urban landscape pattern change characteristics at different stages of urbanization. The results showed that the urbanization of Zhangjiagang City could be divided into two stages which were the urbanization of Zhangjiagang City from 1991 to 2001 and the suburbanization of Zhangjiagang City from 2001 to 2006 based on landscape metrics' change characteristics. During urbanization, the response was obvious in the urban center of Zhangjiagang City, and urban landscape pattern changed greatly. During suburbanization, the response was obvious in the rural area of Zhangjiagang City and rural landscape pattern changed greatly. The urbanization of Zhangjiagang City conformed to the urbanization mode based on population theory and extension theory. Urbanization firstly affected the urban center, and then extended to its surrounding areas, and further influenced widespread rural areas. During suburbanization, agricultural land had decreased and been seriously destroyed; thus, it should strengthen the protection of agricultural land.

Effects of Urbanization on the Quantity Changes of Microbes in Urban-to-rural Gradient Forest Soil

Three typical rural-suburban-urban artificial wetlands Pinus elliottii forest in Nanchang City were selected as research objects to mensurate the soil nutrient content.And the annual average values and seasonal changes of microbes in forest soil were analyzed.The results showed that soil bulk density,total phosphorus （TP） and pH increased,while soil organic carbon （SOC）,total nitrogen （TN） declined with rural-to-urban gradient.At different eco-boundary,annual average values showed that actinomycetes quantity bacteria quantity fungi quantity.Total microbe number was urban suburb rural areas.The number of bacteria and fungi was urban suburbs rural areas,but the number of actinomycetes was suburb urban rural areas.Eco-boundary,season and microbes actinomycetes and fungi reached an extreme significant level （P 0.001）.Bacteria in soil at different eco-boundary had significant effects,but season had no significant effect on bacteria.Eco-boundary and season had a very significant interaction on actinomycetes and fungi （P 0.001）,but they had no significant interaction on bacteria （P 0.05）.Eco-boundary showed significantly positive correlation with actinomycetes and fungi （P 0.001）,but season had no significant corelation with microbes.In conclusion,urbanization process caused the physical-chemical properties changes of forest soil and affected the amount of soil microbes obviously.

Development Mode for the Characteristic Urbanization of Rural Areas in Heilongjiang Province

By analyzing the urbanization of rural areas in Heilongjiang Province,the authors pointed out the existing problems:insufficient motive power of its subjects,low construction level,less prominent functional features of townlets,low scale merits,low efficiency of resource distribution and so on.According to the classification of its townlets,the following 4 modes were given for the rural urbanization of Heilongjiang:A.Motivated by Ecological Construction.It is to solve population problems through ecological migrants,enhance infrastructure construction of townlets,strengthen their capacity of concentrating and absorbing resources;B.Motivated by featured agriculture.It is to develop featured industries on the basis of featured resources with market as the orientation,create a favorable exterior development environment for featured agriculture with the help of government;C.Based on Competitive Tourist Products.It is to coordinate the development of tourism and townlets through scientific planning,design competitive tourism projects and build famous tourism towns;D.Driven by Trade and Processing Industry.It is to promote the capacity of these towns in developing foreign trade,improve policy environment and trade facilities.All these 4 modes are proposed on the basis of actual conditions to give more choices for the characteristic urbanization of its rural areas.

Research on Budding "Villages in Cities" during Urbanization Process in Lanzhou City of China——A Case Study of Chaijiahe Village,China

By introducing the theory of suburb urbanization,it was considered that budding villages in cities emerged with the close relation between city and suburb during rapid urbanization process.The paper had briefly analyzed development of villages in cities in China.By taking villages in Lanzhou City for example,it had studied geological location,appearance,spatial structure,economy and demographic feature of budding villages in cities.Furthermore,with Chaijiahe Village of Xiguoyuan Town as case study,empirical study had been conducted and development thought of Chaijiahe Village as budding village in city had been discussed.It emphasized that it should control the development scale of villages,economically and intensively utilize lands;develop industrialized high-efficiency agriculture and leisure agriculture,develop lily economy and explore the potential of characteristic industries;realize integration of urban and rural development;strive to develop education,improve villages' quality and cultivate villagers of new generation who possessed pioneering spirit and modern agriculture technology.On this basis,it summarized approaches to realize sustainable development of budding villages in cities.

Patterns of species diversity and functional diversity of breeding birds in Hangzhou across an urbanization gradient

Given the rapid rise in human population and increasing urbanization,it is important to understand their potential impacts on biodiversity.From March 2007 to August 2007,we conducted bird surveys in 90 strip transects,each 3 km long and 100 m wide,along a gradient of urbanization in Hangzhou,China.This gradient spanned a range of urbanization levels including urban areas,rural-urban continuum areas,farming areas,mixed forest/farming areas and forested areas.We recorded 96 breeding bird species and classified them into nine functional groups based on nesting requirements.The nine functional groups consisted of canopy nesters,shrub nesters,canopy/shrub nesters,natural cavity nesters,building nesters,natural cavity/building nesters,ground nesters,water surface nesters and parasitic nesters.Species and functional diversities were estimated based on the Shannon-Wiener index.Environmental data of each transect as human disturbance,vegetation cover and building index were also measured,and a synthetic urbanization index of each transect was introduced based on these data.We used regression analyses to model the relationship of species abundance,species diversity,functional abundance and functional diversity with this synthetic index.The results show that urbanization significantly reduces species richness,species diversity,functional richness and functional diversity,but the specific patterns differed.The relationship between species abundance/species diversity and urbanization is linear.In contrast,the relationship between functional diversity and urbanization was quadratic.In other words,with increased urbanization,functional diversity declined only slightly at first but then dropped at an accelerating rate.This implies that,although moderate urbanization reduces species diversity of breeding birds,it affects functional diversity of breeding birds only slightly in Hangzhou.The regression analysis of species diversity and functional diversity suggests a quadratic relationship between species diversity and functional diversity,i.e.,a linear relationship between species diversity and functional diversity can only exist at low diversity levels across urbanization gradients and increasing species abundance does not lead to an increase in functional diversity at the highest diversity levels.