Multi-source Data-driven Identification of Urban Functional Areas:A Case of Shenyang,China

Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of human-land interaction.In this paper,based on multi-source big data include 250 m×250 m resolution cell phone data,1.81×105 Points of Interest(POI)data and administrative boundary data,we built a UFA identification method and demonstrated empirically in Shenyang City,China.We argue that the method we built can effectively identify multi-scale multi-type UFAs based on human activity and further reveal the spatial correlation between urban facilities and human activity.The empirical study suggests that the employment functional zones in Shenyang City are more concentrated in central cities than other single functional zones.There are more mix functional areas in the central city areas,while the planned industrial new cities need to develop comprehensive functions in Shenyang.UFAs have scale effects and human-land interaction patterns.We suggest that city decision makers should apply multi-sources big data to measure urban functional service in a more refined manner from a supply-demand perspective.

Artificial Precipitation Enhancement Weather System and the Operation Timing in Shenyang Area

By using the mathematical statistics and classification,the artificial precipitation enhancement cases in Shenyang area were analyzed.The results showed that the precipitation enhancement weather systems mainly included the northeast cold vortex,high-altitude trough,North China low-pressure,high-pressure rear and cold front cloud system.The appropriate height of precipitation enhancement was about 3 000-6 000 m in the middle and upper part of the cloud layer.The timing of precipitation enhancement should be in the radar's monitoring.The systems moved slowly or maintained stably in the developing or mature stages.The aircraft rainfall enhancement should be used in the stable and deep cloud layers.The rocket and antiaircraft gun rainfall enhancement should be used in the unstable move.

Temperature Variation and Mutation Analysis over the Past 59 Years in Shenyang

In this paper,based on the observation data of air temperature during 1951-2009 in Shenyang,the interannual and interdecadal variation of annual average temperature,maximum and minimum temperature in Shenyang were conducted the statistical analysis by means of linear trend estimation and mutation detection by using Mann-Kendall method.As was demonstrated in the results,the annual average temperature,maximum and minimum temperature in Shenyang showed an upward trend,whose linear tendency rate was 0.231,0.181 and 0.218 respectively.The increment trend of annual average temperature,maximum and minimum temperature was extremely clear.The increase in minimum temperature was more significant than that in mean temperature and maximum temperature.The abrupt change point of annual mean temperature in Shenyang appeared in 1981;the abrupt change point of annual mean maximum temperature appeared in 1994;the annual mean minimum temperature underwent mutation in 1978.

Diurnal Variation Characteristics of Summer Rainfall in Shenyang

By the hourly rainfall record in Shenyang over 48 years from 1961 to 2008,the basic climate characteristics of diurnal variation in summer rainfall were studied in Shenyang.The results showed that diurnal variation in summer rainfall displayed coincident rules in precipitation and rainfall frequency in Shenyang.The diurnal variation had two peak value intervals.One peak value was in afternoon to dusk.The other peak value happened in early morning.From afternoon to the first half of the night,the rainfall peak value was mainly caused by the rainfall event whose duration was less than 6 hours.From latter half of the night to early morning,the rainfall peak value was mainly caused by the rainfall event whose duration was more than 6 hours.

Study on the Changes of Precipitation and Sunshine in Shenyang from 1951 to 2009

Based on the data of precipitation in Shenyang from 1951 to 2009,the variation characteristics of precipitation and sunshine hours in Shenyang in recent 59 years were analyzed and studied comprehensively from different time scales of annual,seasonal and monthly,etc..And the relationship between the precipitation and sunshine duration was analyzed.It was concluded that the changes of precipitation between years is big,the distribution of the precipitation among four seasons is uneven,and the overall change trend of the precipitation is in downward from 1951 to 2009.It was also found that the sunshine duration changes are generally in decreased trend.

Study on the Characteristics of Changes in Air Temperature and Precipitation in Shenyang in Recent 50 Years

Based on the data of monthly average air temperature,extreme maximum,minimum air temperature and precipitation of Shenyang from 1960 to 2009,the climate changes and its characteristics in Shenyang in recent 50 years were comprehensively analyzed and studied.The results showed that the increasing trend of air temperature in recent 50 years was obvious.With the rising of the air temperature,the precipitation in Shenyang City showed a decreasing trend.

Ecological Garden City Green System Plan in Shenyang City

Based on analyzing the current situation of green space in Shenyang City, the plan conception and goal of an ecological garden city green space system is proposed. Taking the corridors in urban areas as a support, a scientific system of urban and suburban areas is established, strengthening the construction of natural ecological green land which is around the city fringe area and the urban river system.

Strategies to Promote the Urban Tourism Competitiveness in Shenyang Based on Modern Service Industry Framework

By describing the status quo of tourism industry in Shenyang and by eval- uating and comparatively analyzing the tourism competitiveness in the four cities of Shenyang, Dalian, Changchuan and Harbin, this paper points out advantages and existing problems in tourism competitiveness of Shenyang and finally comes up with strategies to promote the competitiveness of tourism in Shenyang.

Analysis of the Maximum Continuous Precipitation Variation in Shenyang in 48 Years

[Objective] The aim was to study the changes of maximum continuous precipitation in Shenyang in recent 48 years.[Method] By dint of the daily precipitation from May to September from 1961 to 2008 and according to simple linear trend estimates and microwave analysis,the maximum consecutive precipitation in each month was analyzed.[Result] The frequency of extreme value for the maximum consecutive precipitation in Shenyang increased since 1990.The decreasing trend of maximum consecutive precipitation from May to September was consistent with that around 1990.The decrease of maximum consecutive precipitation amount had tendency to decrease along with the passing of time.There was 5 years temporal scale period of maximum consecutive precipitation from May to September in Shenyang.Maximum value occurred in 1973 and the minimum value occurred in 2000.[Conclusion] The study had important reality meaning to the understanding of climate changes in Shenyang and disaster prevention and relief work of extreme climate incidents.

Temporal-spatial distribution and variability of cadmium contamination in soils in Shenyang Zhangshi irrigation area,China

Heavy metal contamination in soils has been of wide concern in China in the last several decades. The heavy metal contamination was caused by sewage irrigation, mining and inappropriate utilization of various agrochemicals and pesticides and so on. The Shenyang Zhangshi irrigation area （SZIA） in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 years duration. This study investigated the spatial distribution and temporal variation of soil cadmium contamination in the SZIA. The soil samples were collected from the SZIA in 1990 and 2004; Cd of soils was analyzed and then the spatial distribution and temporal variation of Cd in soils was modelled using kriging methods. The kriging map showed that long-term sewage irrigation had caused serious Cd contamination in topsoil and subsoil. In 2004, the Cd mean concentrations were 1.698 and 0.741 mg/kg, and the maxima 10.150 and 7.567 mg/kg in topsoils （0-20 cm） and subsoils （20-40 cm） respectively. These values are markedly more than the Cd levels in the second grade soil standard in China. In 1990, the Cd means were 1.023 and 0.331 mg/kg, and the maxima 9.400 and 3.156 mg/kg, in topsoils and subsoils respectively. The soil area in 1990 with Cd more than 1.5 mg/kg was 2701 and 206.4 hnl2 in topsoils and subsoils respectively; and in 2004, it was 7592 and 1583 hm^2, respectively. Compared with that in 1990, the mean and maximum concentration of Cd, as well as the soil area with Cd more than 1.5 mg/kg had all increased in 2004, both in topsoils and subsoils.

Character and Causes of Population Distribution in Shenyang City,China

Character of population distribution is one of the focuses studied by urban geography. Using the fifth national census data as basic data and using areal interpolation method, this paper analyzes character of urban population dis- tribution of Shenyang City, Northeast China, in terms of three aspects of statistical character, spatial auto-correlation and spatial structure. Furthermore, this research analyzes the factors affecting the population distribution of the city. The main conclusions include: 1) There is an obvious structure character of population distribution in the grid with a grain of 300m, which is appropriate scale when researching population distribution in Shenyang City. 2) Urban population dis- tribution has the character of assembling while population density distribution takes on variability in Shenyang City. 3) Population density distribution shows spatial auto-correlation within 7.36km. Spatial heterogeneity of population density is low. 4) Urban center, population distribution barycenter and population density maximum points separate each other. Population density distribution has multi-cores character. 5) Layout of governments, primary schools, middle schools, colleges, hospitals and marketplaces affects population distribution directly. With the increase of distance to these factors, population density decreases as logarithm.

DISTRIBUTION OF LEAD IN URBAN SOIL AND ITS POTENTIAL RISK IN SHENYANG CITY, CHINA

The horizontal and vertical distribution characteristics of Pb in urban soil of Shenyang City, China were investigated in this study. The range of Pb concentration in the soil was 22.02-2910.60mg/kg. The standard deviation was 443.07mg/kg, and coefficient of variation was 1.64. Tiexi District was seriously contaminated by lead. In general, Pb concentration in the soil decreased with distance from pollution source. Lead concentration varied in different functional areas with the order of industrial area>commercial area>residential area>suburb>reference area. Pb concentration decreased with the depth of soil profile. Both geo-accumulation index and ecological risk index were used to estimate the potential risk of soil Pb pollution in Shenyang City. The results showed that the high potential risk area included Tiexi District and traffic roads.

INDUSTRIAL TRANSFORMATION OF SHENYANG CITY

Industrial transformation represents a unique economic phenomenon in China’s regional economy, and old industrial city reconstruction has long been a key problem that affects state security. As a typical old industrial city in China, Shenyang established its heavy industrial city position in the First Five-year Plan period(1953-1957), and this industrial structure has been consolidated for a long time. After 1978, Shenyang began its long lasting industrial reconstruction in an all-round way by 3 main initiatives including restructuring economic system, upgrading traditional industrial technology and developing high-tech industry. In the end of the 1990s, it could be identified that remarkable structural changes took place in city economy at large as well as individual industrial sector. According to the GDP proportion change, Shenyang is on the way to a high level industrial structure. The secondary industry also engendered significant shifting as smelting and textile industry declined sharply but IT industry increased largely. Although the ratio of the heavy industry to the light industry changed periodically, the heavy industrial output value most time kept a high proportion over 60% of the gross industrial output value in the past five decades. Shenyang has favorable conditions for developing equipment manufacturing industry, but it should carry out the program by establishing its leading role in urban economy plan, building "Theme Industrial Parks", improving Tiexi Industrial Zone, removing any kind of system barrier, enlarging private and other ownerships economy and improving technology, marketing and management by IT application. In response to economy globalization, Shenyang needs to expand the cooperation worldwide and improve the cohesion with surrounding cities.

Simulation Analysis on Spatial Pattern of Urban Population in Shenyang City,China in Late 20th Century

The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distribution of population in the process of urban transformation, resulting in the change of urban spatial structure. Based on the sub-district data of Chinese national population censuses in 1982, 1990 and 2000, this study simulates the evolution pattern of spatial distribution of urban population in Shenyang City. Using statistical method and exploratory spatial data analysis (ESDA), we found that the population distribution, on the whole, has presented a balanced and decentralized trend since the 1980s, which characterizes with Chinese suburbanization. Furthermore, based on the investigation of the pattern of population distribution, it is concluded that the negative exponential model fitted the distribution best, and population concentration in the inner suburb kept increasing gradually, meanwhile, the spatial structure of population distribution has presented a polycentric feature since the 1980s. The parameters of the model show that population in the urban core concentrate significantly all the time. The increase of population in the inner suburb influences the population distribution pattern more and more importantly, but the concentration intensity of population cores in inner suburb is still low.

Climate Changes and Countermeasures for Meteorological Disasters during Production Period in Vegetable Greenhouse in Northern Shenyang Province

[Objective] The aim was to study the climate changes and countermeasures for meteorological disasters during production period in vegetable greenhouse in northern Shenyang. [Method] By dint of local climate data in recent 38 years and using the conventional method of mathematical statistics, the climate changes and countermeasures for meteorological disasters during production period in vegetable greenhouse in northern Shenyang were expounded. [Result] In general, the sunshine condition in new area of Shenyang was normal. Winter sunshine time in Shenyang was short (551). Sunshine hours in each year were decreasing each year, but the decreasing span was not distinct. The temperature climate tendency during growth period of vegetables in greenhouse in new area of north Shenyang was 0.371 ℃/10 a. The winter climate trend rate of 0.313 ℃/10 a; Though the climate was increasing, the wave range was large, difficult to produce; in the cold period (November to March), precipitation in each year and rainy days were increasing, having large influence on the production of vegetables in greenhouse. The low temperature and cloudy days were the characteristics of climate in winter in that area, having disadvantageous to the development of vegetables. Warming measures in winter was expected to conduct. [Conclusion] The study provided scientific accordance to the development of agriculture industry in the local area.

Analyzing Industrial Structure Evolution of Old Industrial Cities Using Evolutionary Resilience Theory：A Case Study in Shenyang of China

The recession and revitalization of old industrial cities concerns urban industrial evolution and its characteristics. Based on the theory of evolutionary resilience, we developed an analytical framework for the industrial structure evolution of old industrial cities, and applied the framework to a case study in Shenyang. The following conclusions are drawn. First, since 1978, Shenyang's industrial growth capacity has shown fluctuation between ‘contraction-expansion'. As the secondary industry has a much stronger expansionary and contractionary capacity for growth, this results in lacking stability leading to industrial structure transformation. Second, since 1999, the orientation towards a high-end manufacturing industry in Shenyang has weakened, and the evolution of the new and old growth path is characterized by low-end orientation. Third, since 2007, Shenyang's industrial innovation output capacity has dropped sharply which has been significantly affected by scientific and technological personnel and enterprise-owed science and technology institutions and to a less extent by R&D expenditure. We applied the resilience theory to study the industrial evolution of an old industrial city, explored new study perspectives on industrial evolution and verified the applicability of the resilience theory. This paper provides a scientific reference for understanding the recent deceleration in economic growth in the Northeast old industrial base, and for exploring new paths toward revitalization.

Numerical simulation of groundwater and early warnings from the simulated dynamic evolution trend in the plain area of Shenyang,Liaoning Province(P.R. China)

Groundwater level is the most direct factor reflecting whether groundwater is in a virtuous cycle. It is the most important benchmark for deciding whether a balance can be struck between groundwater discharge and recharge and whether groundwater exploitation will trigger problems pertinent to environment, ecology and environmental geology. According to the borehole and long-term monitoring wells data in the plain area of Shenyang, a numerical groundwater model is established and used to identify and verify the hydrogeological parameters and balanced items of groundwater. Then the concept of red line levels, the control levels of groundwater is proposed, the dynamic evolution trend of groundwater under different scenarios is analyzed and predicted and groundwater alerts are given when groundwater tables are not between the lower limit and the upper limit. Results indicated:(1) The results of identification and verification period fitted well, and the calculation accuracy of balanced items was high;(2) with the implementation of shutting wells, groundwater levels in urban areas of Shenyang would exceed the upper limit water level after 2020 and incur some secondary disasters;(3) under the recommended scenario of water resources allocation, early-warnings for groundwater tables outside the range would occur in the year of 2020, 2023, 2025 respectively for successive wet, normal and dry years. It was imperative to reopen some groundwater sources and enhance real-time supervision and early-warning to prevent the occurrence of potential problems.

Analysis of Spatial Scale Effect on Urban Resilience:A Case Study of Shenyang,China

Based on urban physical space and theory of landscape ecology,a triune assessment framework—‘size-densitymorphology’—was constructed in order to analyze the spatial pattern and the scale effect of urban resilience in Shenyang of China in 2015,and to explore the main impact factors of landscape under different spatial scale backgrounds.The results show that:1)Urban resilience is an optimal combination of the resilience of size,density,and morphology.The urban resilience of Shenyang displays scale effect;the overall resilience level increases with the increase in scale,while the spatial difference and spatial similarity tend to decrease resilience.2)As 2 km,1 km and 2 km are scale inflection points of average value curves for size resilience,density resilience and morphology resilience,respectively in an urban setting;the optimal scale unit of comprehensive resilience is 1 km.Choosing 1 km–2 km as the basic spatial scale better depicts overall pattern and detailed characteristics of resilience in Shenyang.The spatial amplitudes of 0.5 km and 1 km are sensitive points for spatial autocorrelation of morphology and density resilience,size,and comprehensive resilience to scale effect.3)The major landscape factors of urban size and morphology resilience transform with scale expansion.Aggregation index(AI)has a significant impact on urban resilience at different scales;its influence increases significantly with the increase in scale.4)The high-level area of comprehensive resilience in Shenyang is the eastern ecological corridor area,while the low value area is the peripheral extension area of the city.To promote the overall level of resilience in Shenyang,this paper argues that the construction of ecological infrastructure should be strengthened in the peripheral extension area in a balanced manner.In the city center,population and building density should be controlled;the intensity of human activities should be reduced;impetus should be placed on landscape heterogeneity;and the homogeneous expansion of the area of construction should be prevented.In the eastern ecological corridors,the exploitation of ecosystem lands should be strictly controlled,and the integrity of the green landscape patches should be maintained.

Change Trends of Accumulated Temperature and Effects on Agricultural Production in Shenyang during Recent 58 Years

[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang, the change trends of ≥0 ℃ and ≥10 ℃ accumulated temperature in Shenyang in recent 58 years were analyzed by means of climatic statistics method, and the effects of accumulated temperature variation on agricultural production were discussed. [Result] In recent 58 years, the first day with temperature ≥0 ℃ advanced 10 d, and the last day put off slightly, while sustained days prolonged 13 d, and ≥0 ℃ accumulated temperature increased by 343 ℃·d; meanwhile, the first day with temperature ≥10 ℃ advanced 9 d, and the last day put off 8 d, while sustained days prolonged 16 d, and ≥10 ℃ accumulated temperature increased by 370 ℃·d; compared with the first 20 years, sustained days with temperature ≥0 ℃ and ≥10 ℃ prolonged 9 d in the last 20 years, and ≥0 ℃ and ≥10 ℃ accumulated temperature increased by 196 and 202 ℃·d, respectively. In addition, the increase of heat resources affected agricultural production in Shenyang. [Conclusion] The study could provide theoretical foundation for grasping heat resources variation and adjusting agriculture distribution.

Spatial distribution of Cd and Cu in soils in Shenyang Zhangshi Irrigation Area(SZIA),China

Heavy metal contamination of soils,derived from sewage irrigation,mining and inappropriate utilization of various agrochemicals and pesticides,and so on,has been of wide concern in the last several decades.The Shenyang Zhangshi Irrigation Area(SZIA) in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 years.This study investigated the spatial distribution and temporal variation of soil cadmium(Cd) and copper(Cu) contamination in the SZIA.The soil samples were collected from the SZIA in 1990 and 2004;Cd and Cu in soils was analyzed and then the spatial distribution and temporal variation of Cd and Cu in soils were modeled using Kriging methods.The results show that long-term sewage irrigation had caused serious Cd and Cu contamination in soils.The mean and the maximum of soil Cd are markedly higher than the levels in second grade standard soil(LSGSS) in China,and the maximum of soil Cu is close to the LSGSS in China in 2004 and is more than the LSGSS in China in 1990.The contamination magnitude of soil Cd and the soil extent of Cd contamination had evidently increased since sewage irrigation ceased in 1992.The contamination magnitude of soil Cu and the soil extent of Cu contamination had evidently increased in topsoil,but obviously decresed in subsoil.The soil contamination of Cd and Cu was mainly related to Cd and Cu reactivation of contaminated sediments in Shenyang Xi River and the import of Cd and Cu during irrigation.The eluviation of Cd and Cu in contaminated topsoil with rainfall and irrigation water was another factor of temporal-spatial variability of Cd and Cu contamination in soils.