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Experiences worldwide indicate that the relationship between energy consumption and economic development is complex. Guangdong Province has experienced a more than threefold increase in GDP since 2005, but it is not clear whether rapid economic growth is at the cost of a large amount of energy consumption. In this study, we employ spatial autocorrelation and hotspot analysis to discover the spatial agglomeration of GDP per capita and energy intensity in Guangdong, China, from 2005 to 2018. Furthermore, panel vector autoregression coupled with a system generalized method of moments is performed to examine the dynamic causal relationship between energy consumption and economic growth under the framework of the Cobb–Douglas production function. We used a multivariate model and grouped studies based on the differences in regional economic development and the results with similar research. The results show that the GDP per capita of the Pearl River Delta (PRD) is significantly higher than that of the peripheral municipalities. However, energy intensity shows an entirely different spatial distribution. The development of the regional economy depends on its own "assembling effect". In regions with significant differences in economic development, it is necessary to conduct grouping studies; otherwise, the overall results will not represent partial results. GDP explains approximately 68.3% of the total variation in energy consumption in the PRD but only approximately 34.5% of that in the peripheral municipalities. We do not confirm Granger causality between energy consumption and economic development. Guangdong can decrease its energy consumption growth without substantially sacrificing its economic growth. The contribution of this study is to propose an analytical framework of the relationship between energy consumption and economic development that integrates time and space perspectives to account for spatial effects in panel analysis. [ABSTRACT FROM AUTHOR] more...

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] more...

The characteristics of land use/land cover (LULC) types may affect the thermal environment of urban zones. In this study, the urban zones of the Pearl River Delta (PRD) were examined to explore the spatiotemporal variations in land surface temperature (LST) from 2001 to 2017, as well as the relationships between LST and various influencing factors. Landscape pattern analysis was undertaken to explore the correlation between patch metrics and LST with resolutions from 100 m to 1 km. The results showed that (1) the high-temperature zones were mainly distributed on built-up land; the area of LST hot spots increased from 16% (2001) to 23% (2017). (2) The mean LST of each LULC type was calculated, indicating that the temperature of forestland was more than 5 °C lower than that of built-up land. (3) The landscape patterns of different land use types exhibited various effects on LST in terms of magnitude and importance. Considering the significance of the landscape indexes, it is necessary to avoid a large-scale layout of a single built-up land type when planning an urban environment. It is thus recommended that multiple contiguous forestlands be planned to mitigate urban heat island (UHI) effects. Furthermore, the landscape patterns and structure of different LULC types have various effects on LST and need to be explored in fine detail. This study helped reveal the impact of different LULC types on LST and provides urban planners in the PRD with optional schemes for mitigating the impacts of urbanization on the UHI. [ABSTRACT FROM AUTHOR] more...

Cities face many challenging environmental problems that affect human well-being. Environmental risks can be reduced by Urban Green Infrastructures (UGIs). The effects of UGIs on the urban environment have been widely studied, but less attention has been given to the public perception of these effects. This paper presents the results of a study in Guangzhou, China, on UGI users’ perceptions of these effects and their relationship with sociodemographic variables. A questionnaire survey was conducted in four public green spaces. Descriptive statistics, a binary logistic regression model and cross-tabulation analysis were applied on the data from 396 valid questionnaires. The results show that UGI users were more concerned about poor air quality and high temperature than about flooding events. Their awareness of environmental risks was partly in accordance with official records. Regarding the perception of the impacts of environmental risks on human well-being, elderly and female respondents with higher education levels were the most sensitive to these impacts. The respondents’ perceptions of these impacts differed among the different green spaces. The effects of UGIs were well perceived and directly observed by the UGI users, but were not significantly influenced by most sociodemographic variables. Moreover, tourists had a lower perception of the impacts of environmental risks and the effects of UGI than residents did. This study provides strong support for UGIs as an effective tool to mitigate environmental risks. Local governments should consider the role of UGIs in environmental risk mitigation and human well-being with regard to urban planning and policy making. [ABSTRACT FROM AUTHOR] more...

Twenty trace elements in fine particulate matters (i.e., PM) at urban Chengdu, a southwest megacity of China, were determined to study the characteristics, sources and human health risk of particulate toxic heavy metals. This work mainly focused on eight toxic heavy metal elements (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn). The average concentration of PM was 165.1 ± 84.7 µg m during the study period, significantly exceeding the National Ambient Air Quality Standard (35 µg m in annual average). The particulate heavy metal pollution was very serious in which Cd and As concentrations in PM significantly surpassed the WHO standard. The enrichment factor values of heavy metals were typically higher than 10, suggesting that they were mainly influenced by anthropogenic sources. More specifically, the Cr, Mn and Ni were slightly enriched, Cu was highly enriched, while As, Cd, Pb and Zn were severely enriched. The results of correlation analysis showed that Cd may come from metallurgy and mechanical manufacturing emissions, and the other metals were predominately influenced by traffic emissions and coal combustion. The results of health risk assessment indicated that As, Mn and Cd would pose a significant non-carcinogenic health risk to both children and adults, while Cr would cause carcinogenic risk. Other toxic heavy metals were within a safe level. [ABSTRACT FROM AUTHOR] more...

Biosorption of Zn from aqueous solutions by biomass of Agaricus bisporus was investigated. The removal rates of Zn by A. bisporus under different parameters (e.g., solution pH, bio-sorbent dosage and initial Zn concentration) were studied. The inhibition of A. bisporus's biosorption by anionic ligands EDTA (Ethylene Diamine Tetraacetic Acid), acetate and citrate) implied that EDTA and citrate might be used as eluting reagents. Regular and simultaneous solution pH change and light metal ions release after biosorption indicated that an ion exchange mechanism was involved. From FT-IR (Fourier Transform Infrared) spectroscopy, the main functional groups participated in biosorption were found. Biosorption of Zn by A. bisporus could be well described by the Freundlich and Langmuir models. In conclusion, the biomass of A. bisporus showed high potential for the treatment of wastewater containing Zn. [ABSTRACT FROM AUTHOR] more...

Urbanization has been the most important process that changed land cover landscape in Guangzhou since reformation, especially since 1990. It is essential for monitoring and assessing ecological consequences of urbanization to understand landscape quantitative characteristics and its changes. Based on four land-cover type maps interpreted from remote sensing TM images of 1990, 1995, 2000 and 2005, combining gradient analysis with landscape metrics, the quantified spatial pattern and its dynamics of urbanization in Guangzhou was got. Three landscape metrics were computed within different regional areas including the whole study area, two transects along two highways (one N-S and the other W-E) and radiation zones with equal distance outwards the city center were set. Buffer zones for transects N-S and W-E were outlined along highways. The following questions should be answered in this paper: What responses were implied with changing spatial grain size or extent for landscape pattern analysis? Could gradient progress of urbanization be characterized by landscape pattern analysis? Did landscape metrics reveal urban expanding gradually? Were there directional differences in land cover landscape pattern during urbanizing development? The results gave some affirmative answers. Landscape pattern exhibited obviously scale-dependent to grain size and extent. The landscape metrics with gradient analysis could quantitatively approach spatial pattern of urbanization. A precise location for urbanized area, like city center and sub-center, could be identified by multiple landscape metrics. Multiple adjunctive centers occurred as indicated by analysis of radiation zones around the city center. Directional differences of landscape pattern along the two transects (N-S and W-E) came into being. For example, fragmentation of landscape in the transect W-E was obviously higher than that in the transect N-S. All in all, some interesting and important ecological implications were revealed under landscape patterns of two transects or radiation zones, and that was the important step to link pattern with processes in urban ecological studies and the basis to improve urban environment. [ABSTRACT FROM AUTHOR] more...

The spatial distribution of meteorological elements is important for understanding the regional meteorology and climate changes. However, previous studies rarely focused on the daily changes of the spatial patterns of meteorological elements due to the limitation of remote sensing (RS) techniques and traditional meteorological methods. In this paper, the regional meteorological elements were simulated by the fifth-generation non-hydrostatic Mesoscale Model (MM5), and the spatial patterns of meteorological elements and their diurnal variations were analyzed in landscape level over the Pearl (Zhujiang) River Delta (PRD), China. The results showed that there were several centers of urban heat islands, cold islands, dry islands, wet islands, high wind over the PRD at noon. The diurnal changes of Moran I of meteorological elements were obvious and they reached the extremum at noon and 2–3 hours after the sunrise. The landscape indices of meteorological elements, such as area-weighted mean Fractal Dimension Index (FRAC_AM), Landscape Shape Index (LSI), Shannon’s Diversity Index (SHDI) and Contagion Index (CONTAG), were more variable at about the sunrise, noon and sunset. The occurrence of wave crests and vales of landscape indices was affected by the surface net radiation, turbulence and local circumfluence. The spatial patterns of meteorological elements correlated well with the land surface, thermal exchanges and local circumfluence. A new approach combining GIS, RS and numerical simulations technologies and the landscape ecology method was presented to analyze spatial patterns of meteorological elements, which may be useful for studying global and regional climate changes. [ABSTRACT FROM AUTHOR] more...