Assessment of selenium pollution in agricultural soils in the Xuzhou District,Northwest Jiangsu, China

Xuzhou City is an important base for coal production and coal-fired power. To evaluate selenium contamination in this area, we sampled agricultural soil, soil profile, irrigation water, bedrock, coal, fly ash, paddy rice, and vegetables from the north of Xuzhou City, and determined their selenium contents. The background level of selenium in the soil profile was 0.08 mg/kg. The selenium concentrations in agricultural soils and irrigation water were in the range of 0.21-4.08 mg/kg and 0.002-0.29 mg/L, respectively. Soils with high selenium content were located closely to coalmines and power plants. The average selenium concentrations in coal and coal fly ash were 5.46 and 2.81 mg/kg, respectively. In contrast, the concentrations of selenium in bedrock and in the soil profile were very low. These results imply that the high selenium level in agricultural soils is mainly caused by anthropogenic activities, rather than by parent material. The arithmetic mean of selenium concentration in paddy rice was 0.116 mg/kg, and in cabbage was 0.05 mg/kg. The selenium concentration in rice was positively correlated with total selenium concentration in soil, suggesting that selenium in soil is readily transferred into the crops. Furthermore, the estimated dietary intake （88.8 μg） of selenium from paddy rice and cabbage exceeds the recommended dietary allowance （55 μg）. Therefore, there is a potential health risk from consumption of local staple food in the study area.

Spatial-temporal Heterogeneity of Green Development Efficiency and Its Influencing Factors in Growing Metropolitan Area: A Case Study for the Xuzhou Metropolitan Area

This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000–2015.The slacks-based measure(SBM)model,spatial autocorrelation,and the geographically weighted regression(GWR)model were used to conduct the analysis.The conclusions were as follows:first,the overall efficiency of green development of the Xuzhou Metropolitan Area decreased,the regional differences and spatial agglomeration shrunk and differences within the region were the main contributors to the regional differences of green development efficiency.Second,the counties with high-efficiency green development were distributed along the coast,and along the routes of the Beijing-Shanghai and the Eastern Longhai railways.A developing axis of the high-efficiency counties was the main feature of the spatial pattern for green development efficiency.Third,regarding spatial correlation and green development efficiency,the High-High type counties in the Xuzhou Metropolitan Area formed a centralized distribution corridor along the inter-provincial border areas of Henan and Jiangsu,whereas the Low-Low type counties were concentrated in the external,marginal parts of the metropolitan area.Fourth,the major factors(ranked in decreasing order of impact)influencing green development efficiency were innovation,government regulations,the economic development level,energy consumption,and industrial structure.These factors exerted their influence to varying extents;the influence of the same factor had different effects in different regions and obvious spatial differences were observed for the different regions.

Chronology and Sources of Mesozoic Intrusive Complexes in the Xuzhou-Huainan Region, Central China: Constraints from SHRIMP Zircon U-Pb Dating

SHRIMP zircon U-Pb dating in the Liguo and Jiagou intrusives indicates that they were formed at -130 Ma in the Early Cretaceous. Most inherited zircons in the Liguo intrusive were formed at 2509±43 Ma. Most inherited and detrital zircons in the Jiagou intrusive were formed at -2500 Ma, -2000 Ma and -1800 Ma. The SHRIMP zircon U-Pb dating in two gneiss xenoliths from the Jiagou intrusive yields the ages of 2461±22 Ma and 2508±15 Ma, respectively. The dating results from inherited and detrital zircons in the intrusives and the gneiss xenoliths imply that the magmas could be derived from the partial melting of the basement of the North China Block (NCB). The magmatism is strong and extensive in the periods from 115 to 132 Ma, which is of typical bimodal characteristics. It is suggested that the lithospheric thinning in the eastern North China Block reached its peak in 115-132 Ma.

Spatial Pattern and Regional Types of Rural Settlements in Xuzhou City,Jiangsu Province,China

This paper principally focuses on the morphological differences,spatial pattern and regional types of rural settlements in Xuzhou City of Jiangsu Province in China.Using satellite images of Xuzhou City taken in 2007 and 2008 and models of exploratory spatial data analysis(ESDA) and spatial metrics,the paper conducts a quantitative analysis of the morphological pattern of rural settlements,and finds significant characteristics.First,rural settlements in Xuzhou City are significantly agglomerated in terms of their spatial distribution;meanwhile,there is significant variation in the geographical density distribution.Second,the scale of rural settlements in Xuzhou City is larger than the average in Jiangsu Province,and the histogram of the scale data is more even and more like a gamma distribution.There are a significant high-value cluster in the scale distribution,and local negative correlation between the scale and density distribution of rural settlements in Xuzhou City.Third,the morphology of rural settlements in Xuzhou City shows relative regularity with good connection and integrity,but the spatial variation of the morphology is anisotropic.Finally,according to the characteristics of density,scale,and form of rural settlements,the rural settlements of Xuzhou City are divided into three types:A high-density and point-scattered type,a low-density and cluster-like type and a mass-like and sparse type.The research findings could be used as the scientific foundation for rural planning and community rebuilding,particularly in less-developed areas.

Construction of green infrastructure in coal-resource based city： a case study in Xuzhou urban area

As an important coal-resource based city in eastern China, coal mining activities have greatly promoted economic development to Xuzhou while resulted in kinds of blocks for sustainable development. Subsidence areas caused by coal mining activities and rapid urbanization process led to the losing of ecological function and decreasing of landscape connectivity in the city. As the important life-support system, urban green infrastructure （GI as short） has great significance in improving human well-beings. Taking Xuzhou urban area as the study object, this paper proposed a green infrastructure construction method based on the principle of ecological priority. Firstly, key ecological patches were identified by GIS and RS methods. Secondly, we established corridors by minimum cost path model. Then, we built GI network and evaluated the ecological importance of different patches. Finally, by comparing the status of patches and coal mining subsidence areas, we proposed a framework for constructing GI network in Xuzhou urban area.

Analysis of Urban Expansion and Driving Forces in Xuzhou City Based on Remote Sensing

Based on satellite remote sensing TM/ETM+ images of Xuzhou city,land use forms of the city in 1987,1994 and 2000 were extracted by using a neural network classification method. The expansion contribution rate and annual expansion intensity index of each administrative district have been calculated and the contribution rate matrices and spatial distribution maps of land use changes were obtained. Based on the above analysis,the characteristics of urban expansion from 1987 to 2000 have been explored. From 1987 to 1994,the expansion contribution rate of Quanshan dis-trict reached 46.80%,the highest in all administrative districts of Xuzhou city; Tongshan town was in a high-speed ex-pansion period; both Quanshan and Yunlong districts were experiencing fast-speed expansion periods while the entire city was expanding at a medium-speed with an annual expansion intensity index of 0.98; the city spread eastwards and southwards. From 1994 to 2000,the expansion contribution rate of Quanshan district reached 43.67%,the highest in Xuzhou; the entire city was in a medium-speed expansion period with an annual expansion intensity index of 1.04; the city has rapidly been extended towards the southeast. According to the contribution rate matrices of land use changes,urban expansion mainly usurps cropland and woodland. A quantitative analysis found that population growth,indus-trialization and economic development are the primary driving forces behind urban expansion.

Molecular Characterization and Drug-resistance of Mycobacterium tuberculosis Strains in Xuzhou, China

To understand the genetic diversity and drug resistance status of Mycobocterium tuberculosis （M. tuberculosis） circulating in Xuzhou of China, the spacer-oligonucleotide typing （Spoligotyping） and multi-loci VNTRs （variable number tandem repeats） analysis （MLVA） were utilized for the genotyping of the isolates. Drug susceptibility test （DST） was performed by the proportion method on the Lowenstein-Jensen （L-J） medium using isoniazid, rifampicin, ethambutol, and streptomycin. By Spoligotyping, 287 M. tuberculosis isolates were differentiated into 14 clusters. Then with 15-1oci MLVA, these strains could be divided into 32 clusters, 228 genotypes. Of 15 VNTRs, 6 loci had the highly discriminatory powers, 6 loci presented moderate discrimination and 3 loci demonstrated less polymorphism. The DST results showed that 46 strains were resistant to at least one first-line anti-tuberculosis agent. There was a difference in the isoniazid resistance between Beijing and non-Beijing genotype strains. We concluded that the combination of Spoligotyping and 15 VNTR loci as the genotyping in our study was applicable for this region, the drug resistant isolates were identified, and the Beijing family was the most prevalent genotype in the rural counties of Xuzhou.

Environmental Effects of Groundwater Development in Xuzhou City, China

Xuzhou City is located in the most northwestern portion of Jiangsu Province, P. R. China. Karst groundwater in the Ordovician and Cambrian Limestone aquifers is the main source of water supply. There are 527 wells in urban areas to exploit the karst groundwater, yielding up to 35 000 m^3 per day. After 1978, urbanization and industrialization of Xuzhou City have continued at a greatly accelerated pace; the population increased from 670 700 （1978） to 1 645 500 （2002）, its GDP from 0.71 × 10^9 $ to 42.7× 10^9 $ and the urban area from 184 km^2 to 1,038 km^2 （built-up city area from 41.3 km^2 to 81.9 km^2）. The volume of karst groundwater withdrawal increased yearly before the operation of a supply plant of surface water in 1992, from 3.85x 10^7 m^3（1978） to 1.34× 10^8 m^3 （1991） and now maintained at 0.1× 10^9 m^3 （2002）. Intensive overexploitation of karst groundwater has caused a continuous descending of the piezometric level and the area of the depression cone increases year after year. These changes have increased the vulnerability of the karst groundwater system and have induced environmental problems such as depletion of water resources, water quality deterioration, groundwater contamination and karst collapse. The largest buried depth of karst groundwater is up to 100 m in the dry season in some areas, while 66 exhausted wells have been abandoned. A change in the thickness of the unsaturated zone due to the drawdown of the piezometric level has caused a change of the chemical environment which has an impact on the physical state and major chemical compositions in groundwater. The contents of Ca^2＋, Mg^2＋, NO3^-, SO4^2- and C1^- in karst groundwater has increased significantly, total hardness （CaCO3 content） rises annually in most pumping wells and exceeds the Standard of Drinking Water of P.R. China. Point source pollution and belt-like pollution along the rivers has caused water quality deterioration. The sudden loss of buoyant support due to rapid drawdown of the piezometric level has induced 7 karst collapses to form 17 pits and has caused an estimated US$ 10 million economic loss. These problems have influenced the quality of development in the city.

Modern tectonic stress field deeply in Xuzhou Coal Mine

By inverting fault slip data, the parameters of 12 tectonic stress tensors in the mine region can be determined. The following characteristics can be obtained for recent tectonic stress fields, which are found deep in the study region. The results show that the recent tectonic stress field mainly presents the characteristics of near NWW-SSE maximum compressional stress and near NE-SW minimum extensional stress, while the stress regimes are mainly of strike slip, part of the reverse-fault type. Recent tectonic stress field in the region is characterized by horizontal components. The maximum principal compression stress direction was from NEE to SEE, the average principal compression stress direction was near NWW-SSE maximum compres- sional stress and near NE-SW minimum extensional. The recent tectonic stress field of the studied area can be controlled by a large tectonic stress area.

Spatial-temporal Heterogeneity of Industrial Structure Transformation and Carbon Emission Effects in Xuzhou Metropolitan Area

Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissions in the Xuzhou Metropolitan Area from 2000 to 2014, with a focus on their relationships and driving factors. Our research indicates that carbon emission intensity from industrial structures in the Xuzhou Metropolitan Area at first showed an increasing trend, which then decreased. Furthermore, the relationship between emissions and industrial economic growth has been trending toward absolute decoupling. From the perspective of the center-periphery, the Xuzhou Metropolitan Area formed a concentric pattern, where both progress towards low emissions and the level of technological advancement gradually diminished from the center to the periphery. In terms of variation across provinces, the ISCB index in the eastern Henan has decreased the slowest, followed by the southern Shandong and the northern Anhui, with the northern Jiangsu ranking last. During this period, resource-and labor-intensive industries were the primary growth industries in the northern Anhui and the eastern Henan, while labor-intensive industries dominated the southern Shandong and capital-intensive industries dominated the northern Jiangsu. In terms of city types, the spatial pattern for industrial structure indicates that recession resource-based cities had higher carbon emission intensities than mature resource-based cities, followed by non-resource-based cities and regenerative resource-based cities. Generally, the industrial structure in the Xuzhou Metropolitan Area has transformed from being resource-intensive to capital-intensive, and has been trending toward technology-intensive as resource availability has been exploited to exhaustion and then been regenerated. Industrial structure has been the leading factor causing heterogeneity of carbon emission intensities between metropolitan cities. Therefore, the key to optimizing the industrial structure and layout of metropolitan areas is to promote industrial structure transformation and improve the system controlling collaborative industrial development between cities.

Study on Land Use/Cover Changes and the Driving Forces in Xuzhou City

Based on the remote sensing data of Landsat 5,landscape indexes were used to analyze the land use/cover changes of Xuzhou City during 1994 and 2005,in order to discover the inside driving system.Fourteen social driving forces were chosen according to the PCA theory,and the social driving forces of land use/cover change were analyzed with the help of SPSS software.The result indicated that population,economy,adjustment of agriculture structure were main impact factors of land use/cover changes.

Analysis of Spatio-Temporal Changes of Land Usein Xuzhou City Based on Remote Sensing

Based on the satellite remote sensing TM/ETM images of Xuzhou city, basic data about land use of the city from 1994 to 2000 are obtained with the neural network classification module of PCI software, and the dynamic con- version matrix of land use is thus calculated. The areas of construction land and water body have increased by 1833.93 hm2 and 804.87 hm2, respectively. On the contrary, the area of cropland has decreased by 3207.24 hm2. The area of cropland converted into construction land makes up 26.84%, and that converted into water body amounts for 8.17% of the total area of cropland in 1994. The variation index of land use degree and the dynamic degree index of land use computed are 1.38 and 57.81%, respectively, which demonstrate that land use in Xuzhou is in a development period and the changes are drastic. The frequency index and importance index of the form in which cropland converted into con- struction land are 29.91% and 68.93% respectively. The results indicate that the change is not only widespread in space but a major form of spatial change of land use in the area.

A Case-control Study of Environmental Risk Factors for Nonsyndromic Cleft of the Lip and/or Palate in Xuzhou,China

In this study, we sought to determine the association between environmental factors and nonsyndromic cleft of the lip and/or palate （NSCLP） to understand the etiology of the disease. A total of 200 NSCLP cases and 327 controls were recruited at the Maternal and Child Health Hospital of Xuzhou City. We conducted face-to-face interviews with the mothers of both cases and controls. The factors increasing the risk of NSCLP were a positive family history [odds ratio （OR）=56.74], pesticide exposure （OR=8.90）, and indoor decoration pollution （OR= 4.32）. On the other hand, the factors decreasing the risk of NSCLP were a high education level （OR=0.22） and supplementation of folic acid （OR=0.23） and multivitamins （OR=0.16）. Positive family history, pesticide exposure, and indoor decoration pollution are associated with the risk of NSCLP. In contrast, high education level and folic acid and multivitamin supplementation are protective factors against NSCLP.

Heavy Metals in Urban Soils of Xuzhou, China: Spatial Distribution and Correlation to Specific Magnetic Susceptibility

The investigation of the anthropogenic contamination by heavy metals of soils is very important for environmental planning and monitoring in urban areas. In the present study, surface soils (0-20 cm) samples from 167 sampling sites in Xuzhou (China) were collected in 2010 and analyzed for heavy metals including Zn, Pb, Fe, Mn, Cu, Cd, Sr, Ba Cr, Ni and Mo via inductively coupled plasma/mass spectrometry (ICP-MS). Compared with their levels in natural soils of China, these metals investigated exhibited a slight build-up in Xuzhou topsoils. The multivariate statistical analyses including factor analysis (FA) and cluster analysis (CA) were performed. The obtained results enabled the identification of two main groups of metals, discriminating Ni, Mo and Cr from Zn, Pb, Fe, Mn, Cu, Cd, Sr and Ba. Signifcant associations between Pb, Zn, Fe and specific magnetic susceptibility (c) indicated that specific susceptibility can serve as proxies for these metals levels in Xuzhou urban soils.

Color Planning and Design of Main Urban Districts of Xuzhou City

Through investigating colors of Xuzhou City, combining with color planning practices in domestic and foreign cities, current colors and characteristics of main urban districts of Xuzhou City were analyzed, overall orientation and design concept of city color were explored, the overall framework of regional building colors and the zoning planning were proposed, to give new concepts for the future city color planning and design.

Planning and Layout Strategies of Urban Institution Pension Service Facilities under the Background of Aging Society: A Case Study of the Main Urban District of Xuzhou City

China has entered an aging society, and the contradiction between the social pension needs rapidly growing in the dty and the lagged pension business is increasingly outstanding. By analyzing the amount, development level, type, sttucture, and space distribution of the institutional pension facilityin main urban district of Xuzhou Qty, this paper has summed up the main problems. Combining the estimation on the number of the elders and pension bed, coordination and planning of institutionalpension facility in the research zone are conducted from three aspects： distribution guidance, ptindple of locating and differentiation configufation, to promote tiie construction of pension agenqr and impel the development of pension business in Xuzhou Qty.

Semi-Industrial Test of Underground Coal Gasification In Well No.2 in Xinhe, Xuzhou

The necessity of underground coal gasification is explained. The condition,technology character,and process of the semi-industrial test of underground coal gasification in well No. 2 at Xinhe, Xuzhou,are introduced. The test results indicate that the technique of long tunnel,large sectiou,two stage underground coal gasification can obtain a large output of coal gas with a high heat value, making the working process stable. So the feasibility of the new techuology is verified. It can be concluded that there will have a good application prospect of the technique in China.

Co-seismic changes of Wenchuan Ms8.0 earthquake and six aftershocks recorded by four deformation instruments at Xuzhou seismostation

Co-seismic changes of Wenchuan Ms8.0 earthquake and six strong aftershocks were recorded by 4 digital deformation instruments at Xuzhou seismostation at an cpicentral distance of 1392 km. The result shows that the straln-step changes and wave motions are caused by the arrival of the corresponding surface waves. The shape and size of the step changes and the response time were different for different instruments, even they were located in the same rock body only 7.65 m to 10.57 m apart. This difference is probably a reflection of different instrument properties, such as sensitivity and frequency response. The earthquake-caused stress changes, which were mainly compression in Xuzhou, had an important triggering effect on far-field strain changes

Analysis of Relationship between Meteorological Conditions and Respiratory Diseases in Xuzhou

Based on daily data of influenza-like cases from four sentinel hospitals as well as meteorological data in Xuzhou from October 2005 to May 2011, number of patients with respiratory diseases in Xuzhou was analyzed, and then relationship between meteorological factors and number of patients with respiratory diseases was discussed. The prediction model of number of patients with respiratory diseases in each month was established to forecast number of patients with respiratory diseases using meteorological data. The results show that people suffered from respiratory diseases more frequently in January and from June to September in Xuzhou. Meteorological factors correlated highly with number of patients with re- spiratory diseases are different due to the difference in climatic characteristics among various seasons. The prediction model could obtain good effect.

Study on the Distribution Characteristics of Thunderstorms in Xuzhou City

[Objective] The study aimed to discuss the distribution characteristics of thunderstorms in Xuzhou City. [Method] Based on thunder- storm observation data during 1978 -2008 provided by Jiuli Mountain station, beginning and ending months, days, duration, frequency, hours and direction of thunderstorms in Xuzhou were analyzed. [ Result] From 1978 to 2008, there were obvious annual variations in thunderstorm days in Xuzhou City. Thunderstorm days were more in July and August compared with other months, while there were no thunderstorms in January and De- comber. Thunderstorms began earliest in February and ended latest in November, with a long span. The longest duration of thunderstorms reached 259 d, accounting for 71% of total days of a year. The maximum frequency of thunderstorms （64） appeared in 1995, and the maximum hours of thunderstorms （4 048 h） appeared in 2003. Thunderstorms occurred most frequently in the southwest, followed by SE and NW. [ Conclusion] The research could provide scientific references for the prevention and control of lightning strokes in Xuzhou in future.