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This study explores the recent shifts in urban policy in Shenzhen, China, through the analytical lens of Peter Hall’s policy paradigm theory. China has experienced rapid urban development since the Chinese economic reform in 1978, resulting in the creation of urban villages (UVs) in the large metropolitan areas with specific civil rights for its inhabitants. Recently a shift is occurring in Chinese urban policy from demolition and reconstruction towards preservation and renewal of these urban villages. By applying Hall's framework, we aim to understand whether these changes in urban policy in Shenzhen signify merely a shift in tactics or represent a broader paradigm shift in response to evolving economic conditions and policy perspectives in China. While our study is centred on Shenzhen, we suggest that similar changes are likely to occur in other Chinese cities in the near future. Through this lens, we offer novel insights into the complex dynamics of urban development and their relationship between changing social and economic conditions. This research is particularly relevant for policymakers, urban planners, and scholars in urban studies. [ABSTRACT FROM AUTHOR]

Based on fieldwork in an urbanized village of Shenzhen, this paper analyzes the place of schools in the reproduction of Chinese state capitalism. It retraces the circuit of socialized capital that allows for the social reproduction of the native elite and the exclusion of many migrant workers in the context of Shenzhen's development as a special economic zone and its efforts to upgrade the economy. The native villagers, now forming an urban upper-class of rentiers, have capitalized on their overseas connections and capital accumulation to finance their school, allowing for their elite's upward social mobility after, but also already under Mao. After China's transition to capitalism, this school has served as an asset in generating value in the context of redevelopment and the real estate-driven upgrading of Shenzhen's economy. Property ownership is now a major criterion in points-based systems for accessing school places. I make two interrelated arguments. First, there is a closer relationship between the secondary circuit of socialized capital and the larger circuit of capital than what the literature on social reproduction implies. Second, the conditionality of quality education upon value generation amounts to separating the population deemed worthy of socialized reproduction and the surplus population that is left out. The paper connects diverse strands of social reproduction theory, Althusser's interpellation and ideological state apparatuses, feminist agentive social reproduction theories, and Bourdieu's capital conversion recuperated within a Marxian framework, to provide an integrated approach to social reproduction within capitalism. [ABSTRACT FROM AUTHOR]

Talent is a key resource in a knowledge economy. It plays a critical role in national economic growth and technological innovation. China's technological power is rising, and its ambitious push for talent is supported by central and local government. Through the lens of Shenzhen, China's Silicon Valley, this article examines the Shenzhen Talent Policy and its effectiveness in attracting both domestic talent and overseas returnees. Document analysis is combined with in-depth interviews with returnee entrepreneurs, university professors, and Shenzhen local government officials to examine talent migration and the effectiveness of talent policy. This study findings reveal that the welcoming and tolerant culture of Shenzhen is key to the city's attractiveness to its existing and potential talent. Entrepreneurial scientists and engineers are likely to return to Shenzhen from abroad for business opportunities in applied innovation and technology commercialization. Academics report an average or dissatisfying attitude towards the scientific environment and professional development. State-led talent policy puts emphasis on technical human capital to meet its urgent developmental needs. The reform of higher education system in Shenzhen is needed to fully realize its technological ambition. In addition, this study shows that younger generation Chinese cares about their personal wellbeing, individual happiness, and career opportunities compared to older generation's emphasis on economic benefits. This article concludes with policy implications on worldwide talent attraction and talent migration in a new geopolitical era. [ABSTRACT FROM AUTHOR]

With the expansion of the global novel coronavirus disease (COVID-19) pandemic, unprecedented interventions have been widely implemented in many countries, including China. In view of this scenario, this research aims to explore the effectiveness of population mobility restriction in alleviating epidemic transmission during different stages of the outbreak. Taking Shenzhen, a city with a large immigrant population in China, as a case study, the real-time reproduction number of COVID-19 is estimated by statistical methods to represent the dynamic spatiotemporal transmission pattern of COVID-19. Furthermore, migration data between Shenzhen and other provinces are collected to investigate the impact of nationwide population flow on near-real-time dynamic reproductive numbers. The results show that traffic flow control between populated cities has an inhibitory effect on urban transmission, but this effect is not significant in the late stage of the epidemic spread in China. This finding implies that the government should limit international and domestic population movement starting from the very early stage of the outbreak. This work confirms the effectiveness of travel restriction measures in the face of COVID-19 in China and provides new insight for densely populated cities in imposing intervention measures at various stages of the transmission cycle. [ABSTRACT FROM AUTHOR]

Based on the 2-min average wind speed observations at 100 automatic weather stations in Shenzhen from January 2008 to December 2018, this study tries to explore the ways to improve wind interpolation quality over the Shenzhen region. Three IDW based methods, i.e., traditional inverse distance weight (IDW), modified inverse distance weight (MIDW), and gradient inverse distance weight (GIDW) are used to interpolate the near surface wind field in Shenzhen. In addition, the gradient boosted regression trees (GBRT) model is used to correct the wind interpolation results based on the three IDW based methods. The results show that among the three methods, GIDW has better interpolation effects than the other two in the case of stratified sampling. The MSE and R2 for the GIDW's in different months are in the range of 1.096–1.605 m/s and 0.340–0.419, respectively. However, in the case of leave-one-group-out cross-validation, GIDW has no advantage over the other two methods. For the stratified sampling, GBRT effectively corrects the interpolated results by the three IDW based methods. MSE decreases to the range of 0.778–0.923 m/s, and R2 increases to the range of 0.530–0.671. In the non-station area, the correction effect of GBRT is still robust, even though the elevation frequency distribution of the non-station area is different from that of the stations' area. The correction performance of GBRT mainly comes from its consideration of the nonlinear relationship between wind speed and the elevation, and the combination of historical and current observation data. [ABSTRACT FROM AUTHOR]

Urban reservoir is one of the important urban drinking water sources, and it is of important significance to ensuring the safety of urban water supply. The water quality of the reservoir is an important factor affecting the safety of water supply. Timely and accurate water quality prediction is very important for the formulation of a scientific and reasonable reservoir water supply plan. Considering the problem of high requirement of basic data in constructing water quality hydrodynamic physical model, this paper established a new data-driven model of water quality prediction in urban reservoir based on the Long and Short-Term Memory (LSTM) model, and the water quality data's decomposition is implemented through the Complete Ensemble Empirical Modal Decomposition with Adaptive Noise (CEEMDAN) method. This model can not only realize the water quality prediction during different foreseen periods, but also solve the problem of low prediction accuracy caused by the randomness and large volatility of the measured data. Taking Xili Reservoir in Shenzhen of China as an example, the prediction of water concentration including total nitrogen, ammonia nitrogen, total phosphorus and PH value of Xili reservoir was realized based on historical monitoring data. Through simulation calculation, the prediction results of total nitrogen, ammonia nitrogen, total phosphorus and PH value in the water quality prediction model are highly consistent with the measured results, it is found that the simulation effect is good, and this model can well simulate the reservoir's water quality concentration change process. For the total nitrogen and ammonia nitrogen, the relative prediction error of the model can be controlled below 10%, which shows the rationality of the built model. The research of this paper can provide an important theoretical and technical support for the water quality prediction and operation plan formulation of Xili Reservoir. [ABSTRACT FROM AUTHOR]

Purpose: In the urban region of Shenzhen, the changes in the concentration of Black carbon (BC) have been evaluated throughout the dry season, and apportioned the BC sources, including in the form of fossil fuel (e.g., vehicle emissions) and biomass fuel (e.g., industrial emissions). Methods: The new seven-channel aethalometer model (AE-33), PM2.5, and meteorological data were collected in the dry season (October–May) from 2019 to 2020, to quantify BC emissions in urban Shenzhen. Explored the source allocation of BC based on Potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) model. Results: We revealed that the mean BC concentration was 2672 ± 1506 ng/m3 in the dry season, with values of 4062 ± 1182 ng/m3, 2519 ± 1568 ng/m3, and 1900 ± 776 ng/m3 in autumn, winter, and spring, respectively. Additionally, we found that fossil fuels have higher contributions to BC concentrations (86.3% to 86.8% in autumn and spring) in the dry season than biomass fuels (16% to 20% in autumn, spring and winter), which is different from Beijing, Nanjing and other large economic zones in China. The diurnal variation in BC and the contribution of fossil fuels indicate that there is a significantly greater increase in BC during peak traffic hours in urban Shenzhen than in other cities. Finally, meteorological parameters and PM2.5 data provided supporting evidence that BC is sourced mainly from local vehicle emissions and industry-related combustion in the western and northeastern/southeastern parts of the study area. Conclusion: This study showed that the concentration of BC is lower than other regions, and the source allocation is mainly local fossil fuels (vehicle emission, etc.). [ABSTRACT FROM AUTHOR]

As a common air pollutant, particulate matter (PM2.5) can lead to serious health risks when inhaled over a long period of time, and it is therefore especially important for urban residents to understand the distribution characteristics of PM2.5 within the urban space. To predict long-term PM2.5 exposure at high resolution in high-density cities and quantify the influence of urban spatial morphological characteristics on the distribution of PM2.5 concentration produced under long-term conditions. The seasonal mean values of PM2.5 concentration from 23 monitoring stations in Shenzhen, China were used as dependent variables, and 6 categories of 502 potential predictor variables including urban/building spatial morphological indicators were used as independent variables. The seasonal land use regression models were developed by combining stepwise supervision and Akaike information criterion (AIC) selection with a leave-one-out-cross-validation (LOOCV) to test the prediction performance of the model. The adjusted R2 values were 0.86, 0.70, 0.70 and LOOCV R2 values were 0.83, 0.58, 0.68 in the first three seasons, respectively. In addition to the variables of land use category (i.e., the proportion of land for industrial and manufacturing, the proportion of land for green space and square, and the proportion of land for municipal utilities) and physical geography category (i.e., the count of parks and squares, average elevation), building coverage ratio and the diversity of building volume were also selected into the model as predictor variables. The R2 contributions of urban/building spatial morphology factors exceeded 10% for all three seasonal models. This study developed seasonal land use regression (LUR) models with good prediction performance for a high-density city and provided high-resolution spatial mapping of PM2.5 under steady-state conditions. The contribution of urban/building spatial morphological indicators to the interpretation of R2 for LUR models confirmed the effect of high-density urban morphology on the distribution of PM2.5 concentration. The quantitative correlation between PM2.5 concentration and spatial morphological factors such as building coverage and building volume diversity can provide a basis for incorporating air pollution dispersion considerations to urban planning at early stage. [ABSTRACT FROM AUTHOR]

Under the variant climate conditions in the transitional regions between tropics and subtropics, the impacts of climate factors on influenza subtypes have rarely been evaluated. With the available influenza A (Flu-A) and influenza B (Flu-B) outbreak data in Shenzhen, China, which is an excellent example of a transitional marine climate, the associations of multiple climate variables with these outbreaks were explored in this study. Daily laboratory-confirmed influenza virus and climate data were collected from 2009 to 2015. Potential impacts of daily mean/maximum/minimum temperatures (T/Tmax/Tmin), relative humidity (RH), wind velocity (V), and diurnal temperature range (DTR) were analyzed using the distributed lag nonlinear model (DLNM) and generalized additive model (GAM). Under its local climate partitions, Flu-A mainly prevailed in summer months (May to June), and a second peak appeared in early winter (December to January). Flu-B outbreaks usually occurred in transitional seasons, especially in autumn. Although low temperature caused an instant increase in both Flu-A and Flu-B risks, its effect could persist for up to 10 days for Flu-B and peak at 17 C (relative risk (RR) = 14.16, 95% CI: 7.46–26.88). For both subtypes, moderate–high temperature (28 C) had a significant but delayed effect on influenza, especially for Flu-A (RR = 26.20, 95% CI: 13.22–51.20). The Flu-A virus was sensitive to RH higher than 76%, while higher Flu-B risks were observed at both low (< 65%) and high (> 83%) humidity. Flu-A was active for a short term after exposure to large DTR (e.g., DTR = 10 C, RR = 12.45, 95% CI: 6.50–23.87), whereas Flu-B mainly circulated under stable temperatures. Although the overall wind speed in Shenzhen was low, moderate wind (2–3 m/s) was found to favor the outbreaks of both subtypes. This study revealed the thresholds of various climatic variables promoting influenza outbreaks, as well as the distinctions between the flu subtypes. These data can be helpful in predicting seasonal influenza outbreaks and minimizing the impacts, based on integrated forecast systems coupled with short-term climate models. [ABSTRACT FROM AUTHOR]

Around 30,000 children living in Shenzhen, Mainland China cross the border to Hong Kong to attend school every day. This paper focuses on the school as a key meso-level organisation that mediates macro-level policies and micro-level everyday life experiences among these children and their families. We advocate a relational, spatial perspective, conceptualising schools as webs of intersecting physical, social and digital spaces, where differences between the "locals" and "others" are played out, negotiated and (re)produced, and in turn giving rise to specific (and understudied) geographies of in/exclusion. Drawing on our qualitative research, we offer a close reading of three exemplary school spaces: (i) the physical classroom and school grounds, (ii) the digital classroom, and (iii) at the school gate. Our findings demonstrate the complex and at times contradictory ways in which "the school" is a place of both inclusion and exclusion. It is a dynamic and power-traversed space where social differences between the "locals" and the "others" are played out, contested and redefined continuously. [ABSTRACT FROM AUTHOR]

The associations between objective and subjective dimensions of the built environment and walking behaviour have been examined extensively in existing studies. However, the interaction effects of those dimensions of the built environment on walking behaviour are understudied and may be more complex than hitherto suggested. Apart from the subjective dimensions of the built environment, walking attitudes also play a role in moderating these relationships. This paper investigates the independent and joint effects of objective neighbourhood characteristics, people's perceptions of the neighbourhood environment, and walking attitudes on the frequency of walking by using Shenzhen as a case study. Since those effects may vary across different kinds of walking trips, the analysis looks separately at three major types of walking at the neighbourhood level—walking for work/school, walking for leisure/recreation, and walking for household responsibilities. Logistic regression analyses confirm that the correlates of people's walking frequency vary considerably among different types of walking. Statistically significant interaction effects of objective neighbourhood characteristics and perceived environment are found. The results suggest that positive perceptions of the environment can compensate for the effect that low objective walkability of neighbourhoods has on people's walking frequency. When seeking to encouraging walking at the neighbourhood level, policymakers should not only concentrate on improving objective neighbourhood characteristics but also consider people's perception of the neighbourhood environment and their attitudes towards walking. [ABSTRACT FROM AUTHOR]

Retail activities are important parts of urban life, but limited empirical research has been conducted to address the changing impacts of physical retail activities and online shopping activities under current growth of e-commerce. This study investigates the impacts of online shopping convenience and physical retail proximity on residential property price in Shenzhen by conducting hedonic price models. The analysis results indicate that home buyers are willing to pay more for better online shopping convenience. By contrast, proximity to physical retail businesses, such as convenience stores and shopping malls, adversely affects nearby residential property price. This analysis gives market players, housing management practitioners and urban planner insights into how online shopping convenience is highly valued by home buyers, and guidance to a more desirable and efficient community design and urban planning in the modern society. [ABSTRACT FROM AUTHOR]

Negative air ions (NAIs) benefit the mental and physical health of humans, but rapid urbanization can decrease the abundance of NAIs. Quantifying the spatial and seasonal distribution of NAIs and determining the factors that influence the concentration during urbanization is thus essential. In the present study of a typical developing urban district in southern China, negative air ion concentrations (NAICs) in 60 forests sites and 30 urban green spaces were quantified on seven consecutive days in each of the four seasons. Large seasonal variations in NAIC were revealed in forests and urban green spaces with trough values in summer. NAIC progressively decreased from forests to urban green spaces and was influenced by local land morphology, vegetation characteristics, and climatic factors. The vast, heavily vegetated northeastern region was the richest area for NAIs, whereas the narrow central region (urbanized area) was the poorest, implying dramatic impacts of urbanization on the spatial distribution of NAIs. The relationship between air temperature and NAIC was better fitted with a quadratic equation than a linear equation. Moreover, the NAIC was more sensitive to local morphology in urban green spaces than in urban forests, indicating the vulnerability of NAIs in urbanized areas. Therefore, the appropriate design of local urban morphology is critical. [ABSTRACT FROM AUTHOR]

With rapid urbanization in China, anthropogenic reactive nitrogen (Nr) releases to urban environment contribute to water resource depletion and serious water quality deterioration. This study assessed nitrogen-related water pollution in an urbanized city (Shenzhen, China) by using the indicators of gray water footprint (GWF) and water pollution level (WPL), concerning potential impacts of aquatic Nr releases on administrate districts and affiliated urban rivers within city. The results showed that urban aquatic Nr releases decreased dynamically with average 15.98 thousand t N during 2001–2016, accompanied with the reduction in gray water footprint from 23.06 × 108 to 15.56 × 108 m3, mainly from residential activities. Administrative districts of Baoan and Longgang were the main regional GWF producers during 2012–2016. Areas containing urban rivers with especially high potential WPLs were mainly located in northern Baoan, and northeast Longgang district, and the risks for water pollution development still spread over urban water networks in Shenzhen City. Several strategies (encourage sustainable lifestyle, target infrastructure improvements and develop district-level GWF reduction targets) are needed to mitigate urban water pollution. This study provides insights into the status of assimilation capacity within a city to mitigate aquatic N pollution, meeting current water challenge. [ABSTRACT FROM AUTHOR]

Shenzhen has abundant river systems, intense tectonic activity and complex geological conditions. The depth of Quaternary deposits is thin and uneven, and the primary bedrock comprises granite with various degrees of weathering, which covers more than 50% of the area of Shenzhen. Karst strata have developed in the eastern part of Shenzhen, and there are five groups of fracture zones in the area. Shenzhen also has some problematic soils, including granite residual soil, and muddy clay and silt. Metro tunnels are constructed using the shield tunnelling method. In Shenzhen, different strata are encountered during metro shield tunnelling, including upper-soft and lower-hard strata, hard rock strata, soft–hard alternating strata, under-crossing river or reservoir strata, muddy clay and silt strata and granite residual soil strata. The various strata encountered during shield tunnelling may result in a series of problems with the geological environment. Environmental geological problems during tunnelling are different for different strata, among which the major issues include serious cutter wear, difficulty in controlling the trajectory of the shield machine, shield machine jam, roof fall and slurry spewing. Different countermeasures should be implemented according to the characteristics of the strata to ensure the safe construction of metro tunnels. In this study, a case study of the Shenzhen Metro Line 10 is introduced, where tunnels pass through three specific strata: hard rock strata, boulder strata and under-crossing reservoir strata. In the future, more engineering cases that pass through different strata can be summarized according to the tunnel construction project in Shenzhen. [ABSTRACT FROM AUTHOR]

Despite the benefits of shellfish consumption, the bioaccumulation of heavy metals in shellfish can endanger consumer's health. The consumption of seafood in Shenzhen (a fast-developing metropolis in China) has received more and more attention. Arsenic (As), cadmium (Cd), copper (Cu), mercury (Hg), and lead (Pb) in ten common shellfish species and associated health risks were analyzed for Shenzhen's consumers by evaluating estimated weekly intake (EWI), non-carcinogenic and carcinogenic health risks to children, adolescents, and adults. In this study, 50 shellfish samples were collected in total. The results showed that the levels of inorganic arsenic (iAs) in Babylonia areolata exceeded the maximum permissible limit set by the food safety guidelines (0.5 mg/kg), while other elements were below the limit in the present guidelines (Ministry of Health of the People's Republic of China, GB 2762-2012). EWI values of children, adolescents, and adults were all lower than provisional tolerable weekly intakes (PTWIs) of all shellfish species. The analysis of total target hazard quotients (TTHQ) showed that the ingested B. areolata in children, adolescents, and adults were all at non-carcinogenic risks; the consumption of Argopecten irradians and Chlamys farreri would pose non-carcinogenic risks for children only. In all age groups, the consumption of A. irradians, B. areolata, C. farreri, and Crassostrea ariakensis would lead to lifetime cancer risk due to Cd bioaccumulation, with toxicity of Pb and iAs to be acceptable and negligible. [ABSTRACT FROM AUTHOR]

Urban faults in Shenzhen are potential threat to city security and sustainable development. To improve the knowledge of the Shenzhen fault zone, interpretation and inversion of gravity data were carried out. Bouguer gravity covering the whole Shenzhen City was calculated with a 1-km resolution. Wavelet multi-scale analysis (MSA) was applied to the Bouguer gravity data to obtain the multilayer residual anomalies corresponding to different depths. In addition, 2D gravity models were constructed along three profiles. The Bouguer gravity anomaly shows an NE-striking high-low-high pattern from northwest to southeast, strongly related to the main faults. According to the results of MSA, the correlation between gravity anomaly and faults is particularly significant from 4 to 12 km depth. The residual gravity with small amplitude in each layer indicates weak tectonic activity in the crust. In the upper layers, positive anomalies along most of faults reveal the upwelling of high-density materials during the past tectonic movements. The multilayer residual anomalies also yield important information about the faults, such as the vertical extension and the dip direction. The maximum depth of the faults is about 20 km. In general, NE-striking faults extend deeper than NW-striking faults and have a larger dip angle. [ABSTRACT FROM AUTHOR]

Purpose: As one of largest energy consumers, the transport sector (TS) has significant impacts on the environment. Shenzhen, a developed megacity in South China, plays a leadership role in promoting the development of energy efficient vehicles in China. Methods: This paper aims to assess the carbon footprint (CF) of the TS in Shenzhen via a Streamlined Life Cycle Assessment method. Consequently, the current environmental performance of the TS is evaluated and improvement potentials are examined. Results and discussion: The results show that CF has gained rapid growth over the past decade at an annual rate of 15.3 %, closely corresponding with the growth of the Gross Domestic Product (18.9 %) in Shenzhen. The total CF in 2013 was estimated as 50.7 million tons (ranging from 41.7 to 59.9). Road based freight transport accounts for the largest share of the TS' emissions. The most significant contributors in this sector are: light duty trucks, urban public transport bus service, and passenger air transport. Meanwhile, this study took new energy vehicles into consideration in order to explore the range of CF mitigation potential in Shenzhen. The potential carbon abatement is not significant in comparison with the impact growth derived from the increasing freight and passenger transport based on the assumption that the transport intensity and its annual growth rate maintain at the current levels. Conclusions: This study offers a useful approach to evaluate the available options for sustainable transport system planning in Shenzhen. For carbon emissions reductions from the TS, policies and technological innovations are essential to facilitate the transition to a low carbon TS. In addition, the methodology developed in this study could be used for assessing CF in other sectors. [ABSTRACT FROM AUTHOR]

Urban sprawl is a major driving force that alters local and regional hydrology and increases non-point source pollution. Using the Bao'an District in Shenzhen, China, a typical rapid urbanization area, as the study area and land-use change maps from 1988 to 2014 that were obtained by remote sensing, the contributions of different land-use types to NPS pollutant production were assessed with a localized long-term hydrologic impact assessment (L-THIA) model. The results show that the non-point source pollution load changed significantly both in terms of magnitude and spatial distribution. The loads of chemical oxygen demand, total suspended substances, total nitrogen and total phosphorus were affected by the interactions between event mean concentration and the magnitude of changes in land-use acreages and the spatial distribution. From 1988 to 2014, the loads of chemical oxygen demand, suspended substances and total phosphorus showed clearly increasing trends with rates of 132.48 %, 32.52 % and 38.76 %, respectively, while the load of total nitrogen decreased by 71.52 %. The immigrant population ratio was selected as an indicator to represent the level of rapid urbanization and industrialization in the study area, and a comparison analysis of the indicator with the four non-point source loads demonstrated that the chemical oxygen demand, total phosphorus and total nitrogen loads are linearly related to the immigrant population ratio. The results provide useful information for environmental improvement and city management in the study area. [ABSTRACT FROM AUTHOR]

In recent years, cost-benefit analysis (CBA) has played an important role in disaster risk reduction (DRR) investment decisions, and now increasing attention is being paid to its application in developing countries. This article discusses government investment choices in DRR against typhoon disasters in Shenzhen, China. While the existing literature mainly focuses on disaster mitigation measures such as structural retrofitting, this study proposes a holistic framework of DRR investments in which structural (windproof retrofitting) and financial (insurance premium subsidies and post-disaster relief) are all taken into account. In particular, intermeasure spillover effects are measured and used in CBA. The results show that insurance premium subsidies yield the highest benefit-cost ratio and should be prioritized in investment. Windproof retrofitting comes in second place in terms of the benefit-cost ratio and can be considered when there is a sufficient budget. These results further confirm the need of a holistic review of government DRR investments to derive policy recommendations, while challenges remain in relation to the probabilistic modeling capacity to support CBA. [ABSTRACT FROM AUTHOR]

With a booming development characterized by new urbanization in current China, urban water consumption attracts growing concerns. An efficient and probabilistic prediction of urban water consumption plays a vital role for urban planning toward sustainable development, especially in megacities limited by water resources. However, the data insufficiency issue commonly exists nowadays and seriously restricts further development of urban water simulation. In this article, we proposed a consolidated framework for probabilistic prediction of water consumption under an incompletely informational circumstance to deal with the challenge. The model was constructed based on a state-of-the-art Bayesian neural networks (BNNs) technique. Three dominated influencing factors were identified and included into the BNN model. Future impact factors were generated by using a variety of methods including a quadratic polynomial model, a regression and auto-regressive moving average combination model and a Grey Verhulst model. Thereafter, water consumption projection (2013-2020) and uncertainty estimates was done. Results showed that the model matched well with observations. Through reducing the dependence on large amount of information and constructing a probabilistic means incorporating uncertainty estimation, the new approach can work better than conventional means in support of water resources planning and management under an incompletely informational circumstance. [ABSTRACT FROM AUTHOR]

In Shenzhen, a complex series of folds and fractures, and intensive metamorphism took place during the pre-Caledonian, Caledonian, and Hercynian to Indosinian orogenies. Then, Yanshanian orogeny, with the most tectonic movement, occurred. Strong invasive activity of granitic magma, a massive blowout of acidic volcanic rock, and magmatism-related mineralisation are the features of Yanshanian orogeny. Moreover, deep faults were also developed and wide folds were formed. A large amount of granite rock was formed from the Yanshanian orogeny in Shenzhen. The outcrop area of the granite in Shenzhen reaches 760 km, almost covers 50 % of Shenzhen land area. Granite is primarily susceptible to chemical weathering. Though weathered, granite and solitary granite boulders are of high uniaxial compressive strength (UCS). The weathered granite may be covered by Quaternary soil with low shear strength, such as backfill, sand, silty clay, and clay. The thickness of the Quaternary soil ranges from 0 to 40 m. Socket diaphragm walls are usually adopted during deep excavation construction in Shenzhen for their safety and low impact on the surrounding environment. When the excavation depth is increased, the socket diaphragm walls are embedded in weathered granite to a depth of between 3 and 10 m. However, the traditional socket diaphragm wall construction is only viable in soft ground, as it is not practical to penetrate hard weathered granite. As a consequence, difficulties arise during construction in the Shenzhen region, such as difficulty in breaking down the rock, socket diaphragm wall collapse and leakage. To solve these construction problems, countermeasures, such as monitoring, heavy hammer dropping, smooth blasting and a modified slurry, are proposed in this study. It can be concluded that the heavy hammer dropping method should be chosen to deal with weathered granite with a UCS of less than 50 MPa and the smooth blasting method should be adopted to deal with weathered granite with a UCS of more than 50 MPa. A case study of a metro station excavation using the smooth blasting method in Shenzhen is also introduced. The successful construction of the socket diaphragm walls demonstrates the applicability of the smooth blasting method. [ABSTRACT FROM AUTHOR]

Kashgar, a westernmost city in the restive Xinjiang Uyghur Autonomous Region bordering Central and South Asia, was paired with the southern city of Shenzhen, the most successful special economic zone for its future development. The development of Kashgar's economy in specific and the Xinjiang in general is a part of China's new Silk Road project which serves multi-purpose goals, such as narrowing regional disparity, reducing ethnic tensions, fighting terrorism and balancing US pivot to Asia. It is skeptical whether the Shenzhen model can be transplanted into Kashgar. The plan of developing Kashgar's economy and establishing Kashgar special economic zone may be considered a new bottle with old wine. The development programmes in the past several decades did not address the roots of ethnic tension, including suppression of cultural autonomy and unequal distribution of the benefits and social costs of economic growth. Besides that, the success of the Shenzhen special economic zone is an exception, not a rule. It was unsuccessful in the past attempts to transfer the successful experience from Shenzhen to other special economic zones. It is skeptical whether the Shenzhen experience can be transplanted to Kashgar, whose geographical location and investment environment was much inferior. [ABSTRACT FROM AUTHOR]

In this study, soil samples around Mawan coal-fired power plant (CFPP) in Shenzhen, a high background radiation area in South China, were analyzed for natural radionuclides. The activity concentration of Ra, Th, and K in soils around Mawan CFPP ranged from approximately 72 to 358 Bq kg (averaged 204 Bq kg), 118 to 432 Bq kg (averaged 265 Bq kg), and 101 to 2168 Bq kg (averaged 1269 Bq kg), respectively, being found to be significantly higher than the world range values. The levels of these radionuclides in soil largely decreased with increasing distance from the CFPP, indicating a technologically enhanced natural radiation near the CFPP. The Ra values for the soil samples around Mawan CFPP ranged from 346 to 878 Bq kg, most of which exceeded the allowed maximum Ra value of 370 Bq kg. The operating of CFPP has increased the total radioactive dose received for the nearby population. [ABSTRACT FROM AUTHOR]

Soil erosion has become a pressing environmental concern worldwide. In addition to such natural factors as slope, rainfall, vegetation cover, and soil characteristics, land-use changes-a direct reflection of human activities-also exert a huge influence on soil erosion. In recent years, such dramatic changes, in conjunction with the increasing trend toward urbanization worldwide, have led to severe soil erosion. Against this backdrop, geographic information system-assisted research on the effects of land-use changes on soil erosion has become increasingly common, producing a number of meaningful results. In most of these studies, however, even when the spatial and temporal effects of land-use changes are evaluated, knowledge of how the resulting data can be used to formulate sound land-use plans is generally lacking. At the same time, land-use decisions are driven by social, environmental, and economic factors and thus cannot be made solely with the goal of controlling soil erosion. To address these issues, a genetic algorithm (GA)-based multi-objective optimization (MOO) approach has been proposed to find a balance among various land-use objectives, including soil erosion control, to achieve sound land-use plans. GA-based MOO offers decision-makers and land-use planners a set of Pareto-optimal solutions from which to choose. Shenzhen, a fast-developing Chinese city that has long suffered from severe soil erosion, is selected as a case study area to validate the efficacy of the GA-based MOO approach for controlling soil erosion. Based on the MOO results, three multiple land-use objectives are proposed for Shenzhen: (1) to minimize soil erosion, (2) to minimize the incompatibility of neighboring land-use types, and (3) to minimize the cost of changes to the status quo. In addition to these land-use objectives, several constraints are also defined: (1) the provision of sufficient built-up land to accommodate a growing population, (2) restrictions on the development of land with a steep slope, and (3) the protection of agricultural land. Three Pareto-optimal solutions are presented and analyzed for comparison. GA-based MOO is found able to solve the multi-objective land-use problem in Shenzhen by making a tradeoff among competing objectives. The outcome is alternative choices for decision-makers and planners. [ABSTRACT FROM AUTHOR]

This work investigated the freshening time and hydrochemical evolution of coastal groundwater in two brackish aquifers in Shenzhen, China. One was the brackish aquifer that resulted from heavy pumping, and the other was the aquifer reclaimed from the coastal sea. Freshening time and hydrochemical evolution of brackish aquifers were quantitatively evaluated using PHREEQC 2.0, a one-dimensional reactive-transport model. Freshening time was shown to mainly depend on pore water velocity, while the chemical composition of groundwater was determined by the cation exchange capacity of the aquifer. It was shown that after heavy pumping ceased, the freshening time for the original coastal aquifer ranged from 20 to over 80 years. While for the coastal reclaimed aquifer, the freshening time was from 85 to 140 years, which depended on the hydraulic conductivity of the fill materials in the reclaimed site. During aquifer freshening, groundwater evolved from Na-Cl type to Ca-Mg-HCO or Na-HCO type. A sensitivity analysis showed that the freshening time was most sensitive to the pore water velocity in the aquifer, while the groundwater chemical composition was most sensitive to the values of cation exchange capacity of the aquifer. As for the dispersivity, it had almost no effect on the freshening time and the chemical composition of groundwater. [ABSTRACT FROM AUTHOR]

Fifty-two surface soil samples from agricultural, forest, and grassland sites were collected from the Shenzhen municipal area for determination of copper and lead levels. The spatial dependence of the measured results was quantified using semivariogram modeling, and structural changes in copper and lead in Shenzhen surface soil were analyzed during the past 20 years from the late 1980s to 2009. The resulting semivariogram direction of copper was from northwest to southwest, while that of lead was from east to northwest. [ABSTRACT FROM AUTHOR]

The rapid urbanization of China is causing a burden on their water resources and hindering their sustainable development. This paper analyzes effective methods to integrated river basin management (IRBM) using Longgang River basin of Shenzhen as an example, which is the city with the fastest rate of urbanization in China and even the whole world. Over the past 20 years, China has undergone a population boom due to the increase of immigrant workers and rapid development of laborintensive industries, which led to the sharp increase of water consumption and sewage discharge. However, the construction of the water infrastructure is still lagging far behind the environmental and social development, with only 32.7% of sewage in the district being treated. Currently, every water quality indicator of the Longgang River basin was unable to meet the required corresponding environmental standards, which further aggravated the water shortages of the region. Thus, an analytical framework is proposed to address the IRBM of the study area. The problems with the current management system include the lack of decentralization in decision-making, lack of enforcement with redundant plans, weak management capacity, financial inadequacy, and a poor system of stakeholder participation. In light of the principles of IRBM and the situation of the region, corresponding measures are put forward, including an increase of power given to sub-district offices, fewer but more feasible plans, capacity building among stakeholders, a combination of planning and marketing for overcoming financial inadequacy, and profound reform in the public participation system. The framework and institutional suggestions could inform similar processes in other representative river basins. [ABSTRACT FROM AUTHOR]

The geomorphological environment is one of the most fundamental variables affecting the development of human society. The mission of geomorphological environment research is to explore the most basic environment and features of our Earth's surface morphology. The results can be applied to resource evaluation, environmental protection and reducing and preventing geological disasters. Thus, it can serve to help achieve sustainable development. This paper examines the Shenzhen east coastal zone as a case strongly influenced by urban expansion. We use modern geomorphological theory and methods, along with GIS and RS techniques, to reveal key characteristics of the geomorphological environment and landform classification. Furthermore, coastal ecosystem evaluation and regional resources sustainable utilization should be considered relative to the corresponding geomorphological environment. Based on this study, we conclude that modern geomorphological theory and methods, supported by '3S' techniques including GIS, RS and GPS, can play an important role in resolving the environment, resources and population problems as well as sustainable development challenges facing humankind at present. [ABSTRACT FROM AUTHOR]

Air pollution has become a serious problem in the Pearl River Delta, South China, particularly in winter due to the local micrometeorology. In this study, atmospheric polycyclic aromatic hydrocarbons (PAHs) were monitored weekly in Shenzhen during the winter of 2006. Results indicated that the detected PAHs were mainly of vapor phase compounds with phenanthrene dominant. The average vapor phase and particle phase PAHs concentration in Shenzhen was 101.3 and 26.7 ng m − 3, respectively. Meteorological conditions showed great effect on PAH concentrations. The higher PAHs concentrations observed during haze episode might result from the accumulation of pollutants under decreased boundary layer, slower wind speed, and long-term dryness conditions. The sources of PAHs in the air were estimated by principal component analysis in combination with diagnostic ratios. Vehicle exhaust was the major PAHs source in Shenzhen, accounting for 50.0% of the total PAHs emissions, whereas coal combustion and solid waste incineration contributed to 29.4% and 20.6% of the total PAHs concentration, respectively. The results clearly indicated that the increasing solid waste incinerators have become a new important PAHs source in this region. [ABSTRACT FROM AUTHOR]

This paper presents a study on the use of best management practices (BMPs) for controlling nonpoint pollution in the Xikeng Reservoir watershed located in Shenzhen, China. A BMP treatment train design, including a pond, a wetland, and a buffer strip placed in series was implemented at the reservoir location. A separate grass swale was also constructed at the site. Low impact development (LID) BMPs, namely a planter box and bioboxes, were used at the parking lot of the reservoir’s Administration Building. Samples were collected during storm events and were analyzed for total suspended solids (TSS), biochemical oxygen demand (BOD5), ammonia nitrogen (NH3-N), and total phosphorus (TP). The removal efficiencies of both BMP systems were evaluated using the Efficiency Ratio (ER) method based on the event mean concentration (EMC) data. In summary, the pond/wetland treatment train removed 70%–90% of TSS, 20%–50% of BOD5, and 30%–70% of TP and NH3-N. The swale removed 50%–90% of TSS, 30%–55% of BOD5, − 10%–35% of NH3-N, and 25%–70% of TP. For the planter box and biobox, the ranges of removal rates were 70%–90%, 20%–50%, and 30%–70% for TSS, BOD5, and ammonia and phosphorus, respectively. [ABSTRACT FROM AUTHOR]

Two field measurements for atmospheric fine particles were conducted in Baoan district of Shenzhen during the summer and winter in 2004. Totally 30 sets of 24 h samples were collected, and then the mass concentrations and chemical compositions were determined. The seasonal variations and secondary pollution characteristics of fine particles during the sampling periods were discussed with meteorological factors. The results show that seasonal variations of atmospheric particles are significant in Shenzhen. The average mass concentrations of PM2.5 and PM10 in summer were 35 μg·m−3 and 57 μg·m−3, respectively, and those in winter were 99 μg·m−3 and 135 μg·m−3, respectively. The concentrations of both PM2.5 and PM10 in winter increased 184% and 137%, respectively, compared to those in summer. PM2.5 accounted for 61% and 75% of PM10 in summer and in winter, respectively, indicating severe fine particle pollution in Shenzhen. During the summer and winter sampling periods, the mean OC/EC ratios were 3.4 and 1.6, respectively. The estimated secondary organic carbon (SOC) averagely accounted for 56% and 6% of the total OC in summer and in winter, respectively, which implies a major contribution of SOC to OC in summer. During the continuous high temperature period in summer, both the concentrations and fractions of secondary aerosol components in PM2.5 were highly elevated, suggesting severe secondary pollution again. The prevailing wind was from South China Sea in summer, and the air quality was good. The prevailing wind in winter was from Mainland China to the north, and the polluted air mass led to poor air quality. [ABSTRACT FROM AUTHOR]

This paper explores the issue of causalities among five different indices of shares issued by Chinese firms, A and B Shares listed in the Shenzhen and Shanghai Stock Exchanges, and H Shares listed in the Stock Exchange of Hong Kong. By measuring cross autocorrelations and conducting Granger causality tests, we found that the causality relationships among the five different indices went through significant changes after early 1996; B Shares became more influential relative to the other shares. B Shares in China have tended to lead H Shares in Hong Kong since 1996. Although A Shares tended to lead B Shares before 1996, such relationships either disappeared or were reversed after 1996. [ABSTRACT FROM AUTHOR]