Wujin District Research Articles

Source apportionment based on EEM-PARAFAC combined with microbial tracing model and its implication in complex pollution area, Wujin District, China

Further improving the quality of surface water is becoming more difficult after the control of main point-sources, especially in the complex pollution area with mixed industrial and agricultural productions, whereas the pollution source apportionment might be the key to quantify different pollution sources and developing some effective measures. In this study, a technical framework for source apportionment based on three-dimensional fluorescence and microbial traceability model is developed. Based on screening of the main environmental factors and their spatiotemporal characteristics, potential pollution sources have been tentatively identified. Then, the pollution sources are further tested based on the analysis of fluorescence excitation-emission matrix (EEM) and the similarity of fluorescence components in surface water and potential pollution sources. At the same time, the correlation between microbial species and pollution sources is constructed by analyzing the spatiotemporal characteristics of microbial composition and the response of main species to environmental factors. Therefore, pollution source apportionment is quantified using PCA-APCS-MLR, Fast Expectation-maximization for Microbial Source Tracking (FEAST), and Bayesian community-wide culture-independent microbial source tracking (SourceTracker). PCA-APCS-MLR could not effectively distinguish the contributions of different industrial sources in the complex environment of this study, and the contribution of unknown sources was high (average 39.60%). In contrast, the microbial traceability model can accurately identify the contribution of 7 pollution sources and natural sources, effectively reduce the proportion of unknown sources (average of FEAST is 19.81%, SourceTracker is 16.72%), and show better pollution identification and distribution capabilities. FEAST exhibits a more sensitive potential in source apportionment and shorter calculation time than SourceTracker, thus might be used to guide the precise regional pollution control, especially in the complex pollution environments.

New Exploration of Rural Mutual Aid Pension Mode under the Background of Active Aging—Based on Field Research in Each Township of Wujin District, Changzhou City

New Exploration of Rural Mutual Aid Pension Mode under the Background of Active Aging—Based on Field Research in Each Township of Wujin District, Changzhou City

District government as a policy entrepreneur: Understanding policy experimentation in China’s Wujin District

ABSTRACT Inconsistent policy implementation has been widely observed in Chinese institutional reforms. The central government has experimented with policymaking in a strategic way against tensions between inherited regulatory deficiencies and ongoing development. And, despite the central government’s authority over local governments, the latter operate with a remarkable degree of discretion. By synthesizing policy experimentation theories and policy entrepreneurship, we consider the Wujin District government, as a policy entrepreneur that identified and acted within a “policy window” and explore how it interpreted and actualized policy tasks set by the central government in relation to the rural land reform. The central government designated 33 county-level administrations as testbeds for removing institutional obstacles to coordinated urban-rural land governance. The Wujin District was granted greater administrative autonomy pertinent to local reform initiatives. Further, the Wujin District reorganized its inter-governmental relations by delegating power downward to forge a reform coalition. Critically, Wujin succeeded in aligning local development priorities with central policy goals. Taking an agent-centric perspective, we also examine historical and contextual factors relevant for behavioral changes. The findings indicate that the Wujin District government acted as an effective policy entrepreneur and on this basis made crucial contributions to policy innovation.

Effects of Livelihood Capital on the Farmers’ Behavioral Intention of Rural Residential Land Development Right Transfer: Evidence from Wujin District, Changzhou City, China

In the process of rapid urbanization and industrialization, there is a significant gap between farmers’ participation and rural homestead reorganization for the more diversified external environment. Despite considerable research focused on homestead withdrawal, the transfer of rural residential land development rights has received comparatively little attention. To realize the optimal use of rural homesteads’ resources and reducing potential living risks, this paper conducted an empirical study on the impact of farmers’ livelihood capital on their behavioral intention of rural residential land development right transfer within Wujin District as an example by incorporating the concepts of livelihood capital and risk perception into the theory of planned behavior (TPB). The results of this research show that the increase in livelihood capital may reduce the level of risk perception. The livelihood capital influences farmers’ intentions towards rural residential land development right transfer through risk perception and individual cognition. Based on the findings of this study, it is suggested to diversify livelihood strategies and improve the quality of livelihood capital, in order to reduce the constraint impact of risk perception on farmers’ behavioral intention (BI).

Impact Mechanism of the Three Pilot Reforms of the Rural Land System on Rural Residential Land Use Transition: A Regime Shifts Perspective

Understanding the impact of the three pilot reforms of the rural land system (TRRLS) on rural residential land use transition (RRLUT) based on the land use transition (LUT) theory is crucial for promoting rural land system reform. However, there is still a lack of research on this, and the LUT theory also needs to be improved from a systematic perspective to eliminate the misunderstanding of LUT in academia. To address this, this study firstly attempts to deepen the conceptual model and the understanding of characteristics of LUT from a regime shifts perspective. LUT is the transformation of the land use system as one regime passes into another, where a difference in the analytical perspective of land use morphology generates different transition results. The process of LUT can simultaneously or solely involve dominant morphology and recessive morphology transitions, and there are two types of LUT: positive and negative transitions. Moreover, LUT in different regions may have pathway differences and the convergence of results. Then, a theoretical analysis framework of the pathways of RRLUT under the TRRLS is constructed to detect the impact mechanism by using Wujin district, China to obtain empirical evidence. The results reveal that the recessive morphology transition of rural residential land in Wujin under the TRRLS is significant, while the dominant morphology transition in land quantity structure and spatial distribution is relatively slow. Furthermore, two internal factors of population urbanization and migration, the demand for rural collective economic development, as well as the two external factors of the TRRLS and market factors, such as nonlocals’ demand for housing and rural enterprises’ demand for land, have, to a certain extent, weakened the resilience of the rural land use system and promoted RRLUT. Here, the TRRLS have, by removing the institutional barrier to RRLUT, become the key to the transition.

State-scalar politics of rural land reform in China: The case of Wujin district

China’s central government has been devoted to advancing its dualistic land administration system, such as by designating pilot areas to explore rural land circulation and marketization. Given the increasingly liberalized rural land development practices at localities, this paper aims to explore the variations between policy-making by the central government and implementation at the local scale in the context of interactive politics. A case study of Wujin District, located in the economically developed Yangtze River delta, was examined to unfold the local policy implementation process as intertwined with scalar politics, rural land politics, and the experimentation features of China’s reform. Conducted qualitatively, crucial policy actors were interviewed across multiple administrative levels ranging from the province, prefecture, county, and township governments to village collectives. It was found that within China’s hierarchical land administration, decentralized policy experimentation encouraged by the central government was compromised by the scalar politics and local governmental power structure when implemented on the ground (i.e., the city-county struggles and the resultant incomplete authorities of the primary policy actor). The findings highlight that central policy design and the autonomy of local governments during the policy-making process should be coordinated by embracing scalar complexity.

Occurrence, spatiotemporal distribution, seasonal and annual variation, and source apportionment of poly– and perfluoroalkyl substances (PFASs) in the northwest of Tai Lake Basin, China

Poly- and perfluoroalkyl substances (PFASs) have attracted mounting attention due to their potential harmful effects and degradation-resistant property. This study continuously monitored the concentration of PFASs for four seasons in two years in the northwest of Tai Lake Basin. The occurrence, spatiotemporal distribution, seasonal and annual variation, and source apportionment of 13 PFASs were investigated in 60 surface water sampling sites and 33 emission sources. The average concentrations of the total PFASs were 205.6 ng L−1 and 171.9 ng L−1 in 2018 and 2019, respectively. This improvement could be mainly attributed to the local industrial restructuring. Furthermore, principal component analysis and heat map-hierarchical cluster analysis were employed to analyze distribution characteristics and the possible sources of PFASs pollution. It showed that perfluorooctane sulfonate (PFOA) mainly originated from the effluents of chemical plants, while the potential source of perfluorohexane sulfonate (PFHxS) included all the three types of emission sources. Besides, two indicators were adopted to evaluate the impact of non-point sources and the result showed the effect of runoff was obvious while the effect of atmospheric deposition was weak. A systematic mass balance calculation showed that the total riverine input flux from Wujin District to Tai Lake was 126.5 kg/a.

Seasonal occurrence and source analysis of pharmaceutically active compounds (PhACs) in aquatic environment in a small and medium-sized city, China

Pharmaceutically active compounds (PhACs) have been widely reported in most megacities in China but seldom in small and median-sized cities. The aim of this study is to investigate occurrence and distribution characteristics of PhACs in a typical small and medium-sized city in China and analyze their sources. 33 PhACs and 4 chiral drugs were selected for a four-season monitoring campaign in Wujin District, Jiangsu Province, a typical small and median-sized city, in 2018. PhACs concentration level in surface water, ranging from ng L−1 to μg L−1, was lower than in large-sized cities and areas in China. Impact from agricultural sources should be concerned in the study area: (1) Significant correlation between concentrations of antibiotics and NH4-N in surface water indicated the potential impact from agricultural sources (fishponds and livestock farms); (2) Government regulating measures on livestock and poultry farms since January 2018 have effectively decreased macrolides and lincosamides emissions into surface water. As for source analysis, CF/CBZ (Caffeine/Carbamazepine) was a feasible indicator to trace untreated wastewater and enantiomeric fraction values of metoprolol (MTP) were also suggested to be helpful for identifying untreated wastewater. The results of both two indicators indicated more input of untreated wastewater to surface water in the northeast area and upstream of Wuyi Canal. To our best knowledge, this is the first study to systematically analyze PhACs in aquatic environment for a small and medium-sized city in China.

Occurrence, source and ecotoxicological risk assessment of pesticides in surface water of Wujin District (northwest of Taihu Lake), China

This study investigated the occurrence and distribution of pesticides in surface water (lakes, major rivers and tributaries) and potential discharge sources (fish ponds, livestock and poultry farms, and sewage treatment plants) in Wujin District (northwest of Taihu Lake), Jiangsu province, China. An analytical liquid chromatography-tandem mass spectrometry method was developed for 38 pesticides, which was applied in the monitoring of 240 surface water samples and 76 potential discharge source samples. Eleven insecticides and five fungicides with temporal and spatial variation were detected in surface water. The total pesticide concentrations in surface water in different seasons were as follows: March > August > June > November. The two most polluting and widespread pesticides were carbendazim (maximum concentration 508 ng L−1, detection rate 100%) and imidacloprid (maximum concentration 438 ng L−1, detection rate 88%). Gehu Lake (S46) and Sanshangang River (S12) were seriously polluted water bodies. Seven insecticides and four fungicides were detected in the potential discharge sources; and their composition changed significantly with the seasons. The concentrations of detected organophosphorus pesticides and neonicotinoids (e.g. acetamiprid in March and dichlorvos in November) in a few non-agricultural planting sources were far greater than those detected in surface water, and hence a few fish ponds, livestock and poultry farms, and sewage treatment plants might be the potential discharge sources of pesticides in the surrounding surface water. The estimated input flux of the studied pesticides from upstream rivers to Taihu Lake was 141.95 kg a−1. Furthermore, more attention should be paid to the medium or high aquatic ecotoxicological risk presented by the levels of organophosphorus pesticides, carbamates, and benzimidazoles.

Monitoring urban land surface deformation (2004–2010) from InSAR, groundwater and levelling data: A case study of Changzhou city, China

Land deformation caused by the overexploitation of groundwater has become a potential geological hazard in Changzhou, China. To reduce the potential damage from deformation disasters, it is quite necessary to monitor them. In this study, C-band ENVISAT ASAR synthetic aperture radar (SAR) datasets acquired from 2004 to 2010 were processed with the small baseline subset (SBAS) interferometric SAR (InSAR) method to investigate the spatial–temporal distribution of land deformation. Levelling survey data were used to assess the deformation accuracy measured by the InSAR method, and groundwater level data were used to analyse the incentives for deformation. The SBAS InSAR results found several subsidence regions in the Wujin district and the central part of the Zhonglou district. The annual deformation rate calculated from the C-band interferograms ranged from −65 to +35 mm/yr in the line of sight (LOS) direction, and the cumulative subsidence ranged from −0.35 to 0.13 m in the vertical direction. The levelling survey data show that the two measurements are generally consistent. Correlation analysis between the groundwater table and InSAR measurements at six groundwater well stations shows that groundwater recharges can cause land rebound within the Changzhou urban region. However, subsidence was also observed simultaneously with a rising water table, which might have been caused by the status of consolidation of the strata. Our study provides scientific evidence on the management of groundwater extraction and the assessment of land-subsidence hazard.

The Urban Rain-flood Risk Division Based on the Cloud Model and the Entropy Evaluation Method—Taking Changzhou as an Example

In order to improve cities’ non-engineering measure capacity to cope with rain-flood disasters and provide emphasis for government’s flood protection, the urban rain-flood risk division was studied. The cloud model can be used to deal with qualitative and quantitative transformation and adapt to randomness and fuzziness of urban rain-flood risk evaluation. By taking Changzhou as a research object, 3 criterion layers, including hazard inducting environment, hazard-affected body and disaster-inducing factors and 11 indexes were selected. The cloud model and entropy evaluation method were chosen to evaluate the urban rain-flood risks. Besides, ArcGIS software was used to draw the urban rain-flood risk division map of Changzhou. The findings showed that regions with the higher rain-flood risk grade included most of areas in Jintan District and Xinbei District, some areas in Wujin District and Zhonglou District. The corresponding flood protection measures should be taken.

Land deformation associated with exploitation of groundwater in Changzhou City measured by COSMO-SkyMed and Sentinel-1A SAR data

Abstract The Urban Agglomeration in Yangtze River Delta is one of the most important economic and industrial regions in China. The City of Changzhou is one of the most important industrial citys in Yangtze River Delta Urban Agglomeration. Activities here include groundwater exploration. Groundwater overexploitation has contributed to the major land deformation in this city. The severity and magnitude of land deformation over time were investigated in Changzhou City. A Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technology, provides a useful tool in measuring urban land deformation. In this study, a time series of COSMO-SkyMed and Sentinel-1A SAR images covering Changzhou City were acquired. SBAS-InSAR imaging technique was used to survey the extent and severity of land deformation associated with the exploitation of groundwater in Changzhou City. Leveling data was used to validate the SBAR-InSAR productions, the error of SBAR-InSAR annual subsidence results was within 2 mm. The results showed that three main land subsidence zones were detected at Xinbei, Tianning and Wujin District. Four subsidence points were selected to analyze the temporal and spatial evolution characteristics of land subsidence. The subsidence rate of P1 to P4 was −2.48 mm/year, −12.78 mm/year, −18.09 mm/year, and −12.69 mm/year respectively. Land subsidence over Changzhou showed a trend of slowing down from 2011 to 2017, especially in Wujin District. SBAR-InSAR derived land deformation that correlates with the water level change in six groundwater stations. Indicated that with groundwater rebound, the land rebound obviously, and the maximum rebound vale reached 9.13 mm.

Measures and effects of schistosomiasis elimination in Wujin District, Changzhou City

To understand the measures and effects of schistosomiasis elimination in Wujin District, Changzhou City, so as to provide the reference for other similar areas. The data of schistosomiasis prevention and control were collected and analyzed in Wujin District, Changzhou City from 1995 to 2015. From 1995 to 2015, the accumulated area for investigating Oncomelania hupensis snail habitats was 15 934.01 hm2 in Wujin District, and the accumulated area with snail habitats was 34.61 hm2, but no schistosome-infected snails were found. The area of snail control by molluscicides was 234.59 hm2, and the area of snail control by environmental reform was 84.48 hm2 in 18 key points. There were 259.3 thousand person-times receiving the examinations for schistosomiasis, and there were 17 314 head of livestock receiving the examinations for schistosomiasis, but no schistosome-infected cases were found. There were 204 2 person-times receiving the extensive chemotherapy. The popularizing rate of sanitary toilets was 99.25% in the whole district. The awareness rate of schistosomiasis control knowledge was 98.08% and the formation rate of proper behaviors was 97.82% in the population. In Wujin District, the aim of schistosomiasis elimination has been performed through the active control measures. However, there are still social and natural risk factors of re-endemic of schistosomiasis, and therefore, the schistosomiasis monitoring work still should be strengthened.

Study of mumps immunity after administrating measles-mumps-rubella vaccine among children aged 2-7 years old in Jiangsu Province in 2015

Objective: To investigate the immunity to mumps after administrating measles-mumps-rubella vaccine (MMR) among children aged 2-7 years old in Jiangsu province in 2015. Methods: A total of 4 190 healthy children aged 2-7 years old, living in local places for at least 3 months, and having been vaccinated at least 1 dose MMR were recruited to the study from Wujin district of Changzhou city, Gaogang district of Taizhou city and Ganyu district of Lianyungang city by using stratified cluster random sampling method between September and November, 2015. Those who did not accept MMR vaccination, who refused venous blood collection, who had affected mumps according to the memory of parents or teachers and who were diagnosed serious disease by clinical doctors were excluded from study. The self-designed questionnaire was used to collect the general information of the subjects and their MMR immunization history; and 0.5-2.0 ml of venous blood was collected from each subject. ELISA was used to detect the mumps antibody level in the serum of patients. Positive was defined as the antibody level ≥108 mU/ml, and negative as <108 mU/ml. χ(2) test was used to compare the difference in positive rates among subjects; and analysis of variance was used to compare the GMC changes in different time points after MMR vaccination. Results: Among 4 190 children, 2 280 were males (54.42%) and 1 910 were females(45.58%), and the positive rate of IgG antibody was 81.38% (3 344). There were 3 156 (95.18%) children vaccinated with one dose MMR, 187 (4.80%) children with two dose MMR, and 1 (0.02%) child with three dose MMR. The difference in positive rate of IgG antibody among different aged subjects showed statistical significance (χ(2)=58.61, P<0.001), the highest positive rate was in group of subjects aged 4-5 years old, at 89.43% (406/454), while the lowest positive rate was found among subjects aged 6-7 years old, at 75.63% (1 648/2 179). The positive rate after one dose of MMR vaccination was 79.14% (3 156/3 988), significantly less than it after two doses (93.03%, 187/201) (χ(2)=22.93, P<0.001). The GMC level at years<1, 1-<2, 2-<3, 3-<4, ≥4 following one dose MMR in the 3 988 children was 152.47, 227.78, 167.08, 126.91, 79.43 mU/ml, whose difference was statistically significant (F=51.29, P<0.001). Conclusion: The sero-prevalence of IgG antibody in the children aged 2-7 years old in Jiangsu province was high. The positive rate among who received two doses MMR was significantly higher than it among who received just one dose, and the GMC level waned with times.

Measles epidemics and seroepidemiology of population in Wujin, Changzhou city, Jiangsu province, China 2015

The measles epidemic was rather severe in Wujin 2015, and a seroprevalence survey of measles antibody was conducted during June to September 2015 in Wjin district of Changzhou city. Blood samples were collected from community health population and convenient samples of residual blood from hospitals. Measles-specific IgG levels were measured by ELISA assay. A total of 122 measles cases were reported 2015 in Wujin district with an incidence of 8.31 per 100000 populations. A large proportion of measles cases were adults ≥20years (62.30%) and infants aged <18months (28.69%). Floating population accounted for 68.57% of all cases. 1070 blood samples aged from 9months to 49years old were collected and the overall seroprevalence and geometric mean titer (GMT) of measles were 82.71% and 551.19mIU/ml, respectively. Although the seroprevalence among children aged 9months to 4years was consistently over 90%, it began to decrease since 24months, and till the age of ≥10years, the seroprevalences were all <80%, however, the seroprevalence rised to above 80% in people over 40years. There were no significant differences between the two blood sample sources in the level of seroprevalence and GMT. Also no significant differences were observed in the seroprevalence of measles and GMT levels between genders. The seroprevalence and GMT in people with measles vaccination were higher than those without measles vaccination or people whose measles vaccination are unknown (P<0.001). Our study indicated that the adult measles cases have become a serious problem in Wujin district, which may mainly relate to the increasing size of the floating population with low measles vaccine coverage. The seroprevalence of measles decreased dramatically with increasing age since teenagers, which may mainly caused by waning vaccine-induced immunity. Therefore, it is necessary to strengthen measles vaccine in these people especially floating population.

Assessment and authentication of malaria elimination in Changzhou City

To analyze the results of assessment and authentication of malaria elimination of 7 county-level cities and districts in Changzhou City, Jiangsu Province, and explore the suitable monitoring methods for malaria after the elimination in this region, so as to provide the evidence for formulating and adjusting the malaria elimination strategies and measures. The data from the network reports of malaria epidemic situation, blood examinations of febrile patients, epidemiological questionnaires of malaria cases, investigation of epidemic focuses and disposal tables were collected and analyzed in Changzhou City from 2009 to 2014. The clinicians were assessed with the closed-book written examinations for their ability of the diagnosis and treatment of malaria. The inspection personnel were assessed by the microscopical examinations of Plasmodium. Totally 30 negative blood slides were reviewed. In the natural village where the last local case of malaria was located, 200 blood filter papers were collected for gene detection of Plasmodium. From 2009 to 2014, 145 malaria cases were reported in Changzhou City. Totally 170 638 febrile patients received blood detections for malaria, of which 137 cases were positive and the positive rate was 0.08%. The majority of malaria cases were imported except 8 local malaria infection cases in 2009 and 2 local malaria infection cases in 2010. Four of seven county-level cities (districts) gained an average score of 20 points on the microscopical examinations of Plasmodium. Liyang City got a minimum average score of 18.8 points. In capacity assessment of malaria diagnosis and treatment, Liyang City gained the highest average score of 19.8 points, and Qishuyan District got the lowest average score of 18.0 points. The malaria elimination assessment scores of the 7 county-level cities (districts) were all above 93 points. Four county-level cities (districts) (Xinbei District, Wujin District, Liyang City, and Jintan City) carried out the active case detections. A total of 731 cases were detected and the results were all negative. Liyang City in 2012, Zhonglou District and Jintan City in 2013, Tianning District, Qishuyan District, Xinbei District and Wujin District in 2014, passed the malaria elimination assessment at county (district) level, respectively. All the 7 county-level cities (districts) of Changzhou City have passed the malaria elimination assessment at a high score. After the malaria elimination, the monitoring should continue to consolidate the achievements.

Analysis of malaria epidemic situation in Changzhou City from 2010 to 2014

To grasp the malaria epidemic situation in Changzhou City from 2010 to 2014, so as to provide the evidence for formulating and adjusting malaria control strategies and measures. The epidemiological data of malaria cases in the special report system from 2010 to 2014 were collected, and the malaria epidemic situation and the diagnosis and treatment of malaria patients were analyzed. There were 132 malaria cases reported in Changzhou City from 2010 to 2014, with a decrease of 27.47% compared to 182 cases from 2005 to 2009. Among the 132 cases, 2 cases were local infected cases and the remaining 130 cases were imported cases. Four cases were clinically diagnosed and 128 cases were laboratory confirmed, with 97 cases of malignant malaria, 14 cases of vivax malaria, 13 cases of ovale malaria, and 4 cases of quartan malaria. The 132 cases were distributed in five districts：56 cases in Jintan City, 51 cases in Liyang City, 19 cases in Tianning District, 3 cases in Wujin District, and 3 cases in Xinbei District. The median duration between the onset and treatment of the disease was 2 days, and the median duration between the diagnosis and treatment was 1 day. The diagnosing units were concentrated on the county-level disease control agencies, and medical institutions at county and municipal levels, accounting for 92.42% (122/132). From 2011 to 2014, there were no local malaria cases. From 2012 to 2014, there have been no local malaria cases in Changzhou City, and the goal of eliminating malaria has been achieved basically. However, there are still many imported malaria cases, and the infected species are diverse. Therefore, imported malaria is still the key of malaria prevention and control.

Scaling-up Strategy as an Appropriate Approach for Sustainable New Town Development? Lessons from Wujin, Changzhou, China

China has achieved rapid urbanization and unprecedented economic booming over the past three decades. Numerous cities and towns dreamed of cloning the miracles of Shenzhen and Pudong, Shanghai, in terms of their international development. However, inappropriate development strategies have meant that the majority of fast expanding urban suburbs or newly developed towns suffer a high ratio of vacant dwellings in real estate markets and a massive loss of farmland. The frequent exposure of these empty cities to mass media or the public has urged urban governments to impose fiscal austerity. These unexpected and negative consequences of urban development have explicit conflicts with sustainability. This paper aims to provide a political economy view of these unsustainable outcomes of new development. To achieve this, the processes and agendas of new city or town planning in Wujin District, Changzhou City, are analyzed and evaluated from the perspective of scale theory. Extensive interviews conducted with local politicians at different levels, planners, real estate agents and local residents facilitate the interpretation of these processes and agendas. It is argued that the legends of Shenzhen and Pudong, Shanghai originate from a modified neoliberal capitalism intervention at the right time and place, with which other peer cities are not comparable. It is concluded that the scaling-up strategy is not appropriate for the local new town development of Wujin, which has led to unsustainable outcomes—empty cities and towns—and created important lessons for the sustainable development of Chinese cities.

Application of network Huff model for commercial network planning at suburban – Taking Wujin district, Changzhou as a case

Three issues of applying Huff Model to predict the service area and potential customer pool in Wujin district's commercial networks are analysed and addressed: (1) the distance variable D in Huff Model can either be defined by customer's Euclidean distance, network distance or network time to the commercial circles, and the three approaches have generated very different results in Wujin's case. The differences could be attributed to a traffic infrastructure in the district; (2) the distance decay parameter λ requires either regression or empirical data to estimate. In this paper, several empirical parameters are examined, and it is further proposed that this parameter can be adapted to a fluctuating parameter if the re-modification of Huff model is adopted; and (3) traditional Huff Model was appeared to be over restrictive in Wujin's application because it could only be applied to commercial circles of same scales, and in this paper, a possible re-modification method of predicting the service area and potential customer pool for the different scale commercial circles (Wujin and Changzhou's business circles) are tested. Additionally, a zoning geometry method to analyse the re-modified models’ validation is illustrated.

Analysis about Influence on Surrounding Lightning Environment of Communication Base Station Based on One Lightning Disaster

With the lightning position data in recent years of Jiangsu, satellite and live data on 3rd,July,2012, the reasons for the damage to office room equipment beside a communication base station in Wujin District, Changzhou were analyzed, and reasonable suggestions were given. Based on the lightning accident, this paper analyzed the reasons of lightning strike to buildings near communication base station from weather, lightning strike probability, the validity of lightning protection device and potential. It is mainly because of lightning electromagnetic pulse. Base station can protect the buildings inside the protective area from direct strike, but which increased the possibility of damage to equipment from lightning impulse, at the same time, direct lightning strike probability in the scattered strike zone may increase. Therefore communication base station should be sufficiently far away from the building, when it cant meet a safe distance, not only the direct lightning protection measures should be taken to protect the station and buildings, but also protection measures against lightning electromagnetic pulse for equipment in buildings around are needed.