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1.
Song  Malin  Zhang  Guijun  Fang  Kuangnan  Zhang  Jing 《Natural Hazards》2015,75(1):243-263

In this article, we used a non-radial DEA under natural and managerial disposability to measure the unified efficiency of 30 administrative regions in China and then evaluated their operational and environmental performances. We proposed the performance progress unified index (PPUI) based on the non-radial DEA methodology in a time horizon under natural and managerial disposability with a crossover to measure the performance variety of DMUs. The results of the unified efficiency measured under natural and managerial disposability showed that both operational and environmental performance in eastern China were the highest among the three regions during 2000–2011. The PPUIs under natural and managerial disposability indicated that the operational and environmental performance of the three regions improved during 2000–2011, and the rate of operational and environmental performance of eastern China was higher than the other two regions.

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2.
The transportation sector is the main energy consumer and carbon emitter in China. To accurately evaluate the dynamic changes in the energy–carbon performance of the sector and to propose alternatives for sustainable development, this paper proposes an approach incorporating the meta-frontier method, global benchmark technology, and non-radial directional distance function. Using this approach, the paper proposes a new definition, named the global meta-frontier non-radial Malmquist energy–carbon performance index (GMNMECPI). GMNMECPI can be decomposed into technical efficiency change (EC), best-practice gap change (BPC), and technology gap change (TGC). This new method was then used to estimate the dynamic changes of energy–carbon performance in China’s transportation sector from 2006 to 2015. The paper also identifies the effect of current policies. The empirical results show that the energy–carbon performance of China’s transportation sector decreased annually by 1.636% during the study period. This reduction was mainly caused by a significant technology lag in the central area while primarily influenced by deterioration in efficiency in both the east and west. There is a distinct heterogeneity in technology across China’s three areas. Based on the findings, the paper closes with policy implications.  相似文献   

3.
Rapid industrialization and urbanization along with a growing population are contributing significantly to air pollution in China. Evaluation of long-term aerosol optical depth (AOD) data from models and reanalysis, can greatly promote understanding of spatiotemporal variations in air pollution in China. To do this, AOD (550 nm) values from 2000 to 2014 were obtained from the Coupled Model Inter-comparison Project (CIMP6), the second version of Modern-Era Retrospective analysis for Research, and Applications (MERRA-2), and the Moderate Resolution Imaging Spectroradiometer (MODIS; flying on the Terra satellite) combined Dark Target and Deep Blue (DTB) aerosol product. We used the Terra-MODIS DTB AOD (hereafter MODIS DTB AOD) as a standard to evaluate CMIP6 Ensemble AOD (hereafter CMIP6 AOD) and MERRA-2 reanalysis AOD (hereafter MERRA-2 AOD). Results show better correlations and smaller errors between MERRA-2 and MODIS DTB AOD, than between CMIP6 and MODIS DTB AOD, in most regions of China, at both annual and seasonal scales. However, significant under- and over-estimations in the MERRA-2 and CMIP6 AOD were also observed relative to MODIS DTB AOD. The long-term (2000–2014) MODIS DTB AOD distributions show the highest AOD over the North China Plain (0.71) followed by Central China (0.69), Yangtse River Delta (0.67), Sichuan Basin (0.64), and Pearl River Delta (0.54) regions. The lowest AOD values were recorded over the Tibetan Plateau (0.13 ± 0.01) followed by Qinghai (0.19 ± 0.03) and the Gobi Desert (0.21 ± 0.03). Large amounts of sand and dust particles emitted from natural sources (the Taklamakan and Gobi Deserts) may result in higher AOD in spring compared to summer, autumn, and winter. Trends were also calculated for 2000–2005, for 2006–2010 (when China introduced strict air pollution control policies during the 11th Five Year Plan or FYP), and for 2011–2014 (during the 12th FYP). An increasing trend in MODIS DTB AOD was observed throughout the country during 2000–2014. The uncontrolled industrialization, urbanization, and rapid economic development that mostly occurred from 2000 to 2005 probably contributed to the overall increase in AOD. Finally, China's air pollution control policies helped to reduce AOD in most regions of the country; this was more evident during the 12th FYP period (2011–2014) than during the 11th FYP period (2006–2010). Therefore this study strongly advises the authority to retain or extend these policies in the future for improving air quality.  相似文献   

4.
Wang  Qian  Zhang  Qi-peng  Liu  Yang-yang  Tong  Lin-jing  Zhang  Yan-zhen  Li  Xiao-yu  Li  Jian-long 《Natural Hazards》2020,100(1):3-15

Natural disaster vulnerability can intuitively reflect the susceptibility of an area to environmental changes. Better understanding the spatial distribution of natural disaster vulnerability is a critical process for taking effective adaptation and management. Although significant achievements have been made in disaster vulnerability, few studies are known about natural disaster vulnerability at the national scale, especially from the typical natural disaster events in China. In this study, with normalizing selected indicators and calculating vulnerability index, we analyzed the spatial distribution of natural disasters vulnerability during 2010–2017 using the geospatial techniques. The results showed that natural disaster vulnerability has certain spatial differences, but different natural disaster can occur in the same area during the study period. Drought disaster can occur in all regions of China, especially in Inner Mongolia. Flood disaster is mainly concentrated in the middle and lower reaches of the Yangtze River and the Yellow River Basin. The wind and storm disaster is chiefly in the northern regions in China. The freezing disaster is widely distributed in China. Furthermore, the regions with low vulnerability were primarily distributed in the eastern coastal region, indicating that the rapid development of economy and technology can resist or mitigate natural disaster to a certain extent. This study offers a solution to study natural disasters and provides scientific basis for disaster prevention and mitigation actions.

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5.
Under the framework of meta-frontier, we employ the slacks-based measurement (SBM)-Undesirable approach to explore China’s provincial energy efficiencies and meta-technology ratios (MTRs) of eight major economic regions during 2000–2014. The results obtained show that: firstly, the SBM-Undesirable model involving a undesirable output of CO2 emission is more reasonable than the SBM model for measuring China’s provincial energy efficiencies. Secondly, there are severe imbalances of energy efficiencies between regions due to their imbalanced energy technologies. Thirdly, energy efficiencies of the southern, eastern and northern coastal regions are high with advanced energy technologies. Energy technology gaps between regional and meta-technologies of southwest, eastern coastal and northern coastal regions are shrinking; however, the ones of remaining regions are widening. Fourthly, energy technology of overall China has a U-shaped trend; however, the ones of provinces in each region are characterized as a club convergence.  相似文献   

6.
This study uses the total-factor energy productivity change index (TFEPCH) to investigate the changes in energy productivity of construction industry for 30 provincial regions in China from 2006 to 2015, adopting the improved Luenberger productivity index combined with the directional distance function. In addition to traditional economic output indicator, this study introduces building floor space under construction as a physical output indicator for energy productivity evaluation. The TFEPCH was decomposed into energy technical efficiency change and energy technical progress shift. Results indicate that, first, energy productivity of China’s construction industry decreased by 7.1% annually during 2006–2015. Energy technical regress, rather than energy technical efficiency, contributed most to the overall decline in energy productivity of China’s construction industry. Second, energy productivity in the central region of China decreased dramatically, by a cumulative sum of approximately 77.1%, since 2006, while energy productivity in the eastern and western regions decreased by over 54.3 and 65.3%, respectively. Only two of the 30 provinces considered—Hebei and Shandong—improved their energy productivity during 2006–2015. The findings presented here provide a basis for decision-making and references for administrative departments to set differentiated energy efficiency goals and develop relevant measures. Additionally, the findings are highly significant for energy and resource allocation of Chinese construction industry in different regions.  相似文献   

7.
Assessment of provincial social vulnerability to natural disasters in China   总被引：2，自引：2，他引：0  
Assessment of social vulnerability has been recognized as a critical step to understand natural hazard risks and to enhance effective response capabilities. Although significant achievements have been made in social vulnerability researches, little is know about the comprehensive profile of regional social vulnerability in China. In this study, the social vulnerability to natural hazards was firstly divided into socioeconomic and built environmental vulnerability. Then, using factor analysis, we identified the dominant factors that influence the provincial social vulnerability in China to natural hazards based on the socioeconomic and built environmental variables in 2000 and 2010 and explored the spatial patterns of social vulnerability. The results indicated that the provincial social vulnerability in China showed significant regional differences. The social vulnerability in the southeastern and eastern regions of China was greater than its northern and central parts over the past decade. Economic status, rural (proportion of agricultural population and percentage of workers employed in primary industries), urbanization, and age structure (children) were the dominant driving forces of variations in provincial socioeconomic vulnerability in two studied years, while lifelines and housing age could explain most of changes in built environmental vulnerability in 2000 and 2010. There were no statistically significant correlations between social vulnerability and disaster losses (p > 0.05), indicating the impact of disasters was also related to the intensity of hazards and exposure. Disaster relief funds allocated to each province of China depended more on its disaster severity than the regional integrated social vulnerability over the past decade. These findings would provide a scientific base for the policy making and implementation of disaster prevention and mitigation in China.  相似文献   

8.
This study argues that export upgrading can, but does not necessarily, lead to environmental improvement. A synergy between global and local linkage determines the likely disjuncture between export upgrading and environmental improvement. On the basis of the panel data covering 261 prefectural-level cities in China during 2003–2011, this study applies the decomposition of export sophistication to quantify diverse upgrading types. It also divides the sample cities into groups and uses the fixed-effect regression by groups to investigate the role of local linkages. Empirical findings indicate that environmental improvement associated with export upgrading in China has largely relied on changing product mix to avoid environmental costs, exhibiting a significant displacement effect. The role of efficiency promotion of production process is still insignificant. Local linkage may alter the environmental effects of export upgrading. Specialisation in polluting production can help cities to change product mix through the agglomeration of related firms. Stringent environmental regulation protects cities from the export–environment disjuncture through imposing additional costs. These findings suggest that the greening efforts of China should take one step further from export restructuring to efficiency promoting.  相似文献   

9.
China’s climate change mitigation strategies and efforts are based on accurate regional carbon emission efficiency (CEE) estimates. Decision-making units which are all data envelopment analysis (DEA)-effective cannot be ranked by using the original DEA model. While previous studies omit environmental factors when gauging resources or environmental efficiency. In this study, we combine a Ruggiero three-stage model with a super-efficiency DEA model (SE-DEA) to solve these two problems. Following this method, we consider environmental factors and thereby compare provincial CEE in China in the new production frontier. The main results obtained are as follows: (1) provincial CEE values differ significantly in the first stage and the third stage; (2) in the third stage, only Eastern China reaches the SE-DEA relatively effective level, where CEE rankings in descending order are: Eastern, Central, and Western China; (3) provinces are divided into four categories in terms of provincial CEE values and per-capita GDPs, and therefore, regional climate and development policies could be oriented due to different categories. This efficiency evaluation methodology and the results obtained in our study not only contribute to understanding this issue, but also could be of specific interest to climate change policy makers in China.  相似文献   

10.
Integrated risk assessment of multi-hazards in China   总被引：1，自引：0，他引：1  
Maps of population exposure, vulnerability and risk to natural hazards are useful tools for designing and implementing disaster risk mitigation programs in China. The ranking of provinces by relative risk to natural hazards would provide a metric for prioritizing risk management strategies. Using provinces as our study unit, from the perspectives of hazard exposure, susceptibility, coping capacity and adaptive capacity, this study first constructed China’s disaster risk index for five types of major natural hazards: earthquakes, floods, droughts, low temperatures/snow and gale/hail. Then, the relative risk level at the provincial scale in China was assessed. Finally, the hotspots with the highest hazard exposure, vulnerability and risk were identified. The results showed that high exposure was a significant risk driver in China, whereas high vulnerability, especially social vulnerability, amplified the risk levels. Similar to the population exposure to disasters, the relative risk levels in the southwestern, central and northeastern regions of China were significantly higher than those in the eastern, northern and western regions. The high-risk regions or hotspots of multi-hazards were concentrated in southern China (less-developed regions), while the low-risk regions were mainly distributed in the eastern coastal areas (well-developed regions). Furthermore, a nonlinear relationship existed between the disaster risk level and poverty incidence as well as per capita GDP, demonstrating that disaster losses in middle-income areas are likely to increase if economic policies are not modified to account for the rising disaster risk. These findings further indicated that research on disaster risk should focus not only on hazards and exposure but also on the vulnerability to natural disasters. Thus, reducing vulnerability and population exposure to natural hazards would be an effective measure in mitigating the disaster risk at hotspots in China.  相似文献   

11.
On the basis of a one-by-one latitude-longitude grid three-dimensional seismic velocity model, the crustal P-wave velocity structure in eastern China (105-125°E and 18-41°N) is obtained, and a set of geotherms for each grid is established for P-T correction on P-wave velocities. The average depths of sub-crustal layers and their average P-wave velocities of 18 tectonic units in eastern China are exhibited. Our result presents a 32-34 km thick crust beneath eastern China, which is thinner than previous studies, with an average velocity of 6.54 km/s, corresponding to a 5 kg/m3 variation in crustal mean density. The thicker upper but thinner middle and lower crust results in a lower average seismic velocity of eastern China. An intermediate crustal composition with a SiO2 content of 59.7 wt% has been estimated. However, there exists a significant lateral variation in the crustal structures among the tectonic units of eastern China. The structure and composition features of some regions in eastern China in  相似文献   

12.
Comparative study of long lake records in different regions in China can provide some significant information about the regional differentiation of the environment and Asian monsoon activities. However, intensively studied lacustrine cores with a span of a few hundred thousand years are very rare in China. The available examples are only three long cores from the Zoige basin in the eastern Qinghai-Tibet plateau, the Qaidam basin in the northern Qinghai-Tibet plateau and the Dianchi basin in the Yunnan plateau respectively. The results show that the regional environmental differentiation since the Mid-Pleistocene involved three stages, i.e. 780-480, 480-160, 160-0 ka B.P. In each of the three stages different regions of China had their own distinctive environmental characteristics, indicating that the uplift of the Qinghai-Tibet plateau played a major role in the environmental differentiation process.  相似文献   

13.
Agriculture produced the largest methane emissions in China. It is of great importance to investigate effect of fertilizer using intensity on the environmental efficiency of China’s agriculture. This paper mainly investigates the determinants of environmental efficiency of China’s agriculture. First, we estimate environmental efficiency of China’s agriculture of 30 provinces from 1997 to 2014 through metafrontier SBM super efficiency with undesirable outputs, which allow for technology heterogeneity in different regions. Then, we compare environmental efficiency in different regions. Furthermore, we also analyze whether heterogeneity of environmental technology widened or decreased. Last, we also explore the determinants of environmental efficiency of China’s agriculture through bootstrap truncation regression. We find that fertilizer intensity negatively affects environmental efficiency. Urbanization has significant positive (1.454) effect on environmental efficiency under metafrontier in the east. It is significant use more organic fertilizer to decrease CO2 (carbon dioxide) emissions. It is important to enhance environmental innovation for China’s agriculture.  相似文献   

14.
Significant advancements have been made in examining the relationship between economic development and disaster losses at the global and national scales, but very little research has been done at the sub-national level, especially in China. Based on socioeconomic and disaster impact data from 31 provinces (municipalities, and autonomous regions) in China from 1990 to 2010, ordinary least squares regression was used to determine the relationship between socioeconomic development and effects of natural disasters. Results showed that economic development played a distinct role in mitigating disaster damages in the whole China and its eastern, central and western regions. There existed a U-shaped relationship between economic growth and disaster losses in the whole China and its eastern region, and an inverted-U nonlinearity linkage in its central and western areas. These findings further confirmed the existence of a nonlinear relationship between economic development and disaster losses. Economic growth had played a more important role in mitigating disaster losses in the central region of China than that in the western one. Further investigations demonstrated that as economic develops, there were fewer deaths caused by natural hazards in whole China and all its three regions. The combination of the lower level of education, higher unemployment rate and greater gross dependence ratio has contributed to the increase in death toll caused by natural disasters, but this trend could be partly offset by wealth growth.  相似文献   

15.
This work extensively investigated global tight sandstone gas, and geologically and geochemically analyzed the tight sandstone gas in China's Ordos, Sichuan, and Tarim basins. We compared typical tight sandstone gas in China with that in North America. We proposed six conditions for the formation of China's tight sandstone gas, and illustrated the geological characteristics of tight sandstone gas. In China, gas-bearing tight sandstones were mainly deposited in continental lake deltas and marine-terrigenous facies basin environments, associated with coal-measure strata, and were mostly buried deeper than 2000 m under a formation pressure of 20–30 MPa, with pressure coefficients varying from overpressure to negative pressure. In other countries, tight gas bearing sandstones were dominantly deposited in marine to marine-terrigenous facies environments, occurred in coal-measure strata, and were mostly buried shallower than 2000 m in low-pressure systems. We systematically analyzed tight sandstone gas in the Ordos, Sichuan, and Tarim basins in terms of chemical compositions, geochemical characteristics of carbon isotopes, origins, and sources. Tight sandstone gas in China usually has a hydrocarbon content of 95%, with CH4 content 90%, and a generally higher dry coefficient. In the three above-mentioned large tight sandstone gas regions, δ13 C1 and δ13 C2 mainly ranges from-42‰ to-28‰ and from-28‰ to-21‰, respectively. Type III coal-measure source rocks that closely coexist with tight reservoirs are developed extensively in these gas regions. The organic petrology of source rocks and the carbon isotope compositions of gas indicate that tight sandstone gas in China is dominantly coal-derived gas generated by coal-measure strata. Our analysis of carbon isotope series shows that local isotope reversals are mainly caused by the mixing of gases of different maturities and that were generated at different stages. With increasing maturity, the reversal tendency becomes more apparent. Moreover, natural gas with medium-low maturity(e.g., Xujiahe Formation natural gas in the Sichuan Basin) presents an apparent reversal at a low-maturity stage, a normal series at a medium-maturity stage, and a reversal tendency again at a high-maturity stage. Finally, we proposed four conditions for preferred tight sandstone gas "sweep spots," and illustrated the recoverable reserves, proven reserves, production, and exploration prospects of tight sandstone gas. The geological and geochemical characteristics, origins, sources, and exploration potential of tight sandstone gas in China from our research will be instructive for the future evaluation, prediction, and exploration of tight sandstone gas in China and abroad.  相似文献   

16.
东亚大地构造发展的重要转折   总被引：206，自引：8，他引：198       下载免费PDF全文
赵越 《地质科学》1994,29(2):105-119
本文根据现实主义原则和现代地质学理论,分析综合了东亚构造地质、古地磁、古生物地理、地质年代学等方面的一些最新研究成果,提出东亚古亚洲洋构造系和古特堤斯构造系向环太平洋主动陆缘的转变最终出现在中侏罗世,著名的燕山运动正是这一重要构造转折的产物。  相似文献   

17.
The assessment of social vulnerability is a requirement for understanding the risk of natural hazards. This paper calculates the social vulnerability index of geological disasters in China with the super-efficiency DEA (data envelopment analysis) model, carries out global and local autocorrelation tests for social vulnerability to geological disasters in each province in China and identifies the characteristics of its spatial distribution pattern. The results show the following. (1) China’s social vulnerability to geological disasters is relatively high and has obvious differences. It represents the pattern of a significant increase by degrees in social vulnerability to geological disasters from east to west and a significantly negative correlation relationship between the vulnerability level and the economic level. (2) Based on the comparative analysis of the mean values of the indexes and the social vulnerability index of geological disasters, it is found that the social vulnerability index of geological disasters in China is directly related to the regional exposure degree and reaction and recovery ability, among which the reaction and recovery ability has great effects on the social vulnerability index. (3) Most of the regions in China are in a high–high clustering area or a low–low clustering area; that is to say, the regions with similar social vulnerability to geological disasters represent the pattern of clustering.  相似文献   

18.
Group velocity dispersion data of fundamental-mode Rayleigh and Love waves for 12 wave paths within southeastern China have been measured by applying the multiple-filter technique to the properly rotated three-component digital seismograms from two Seismic Research Observatory stations, TATO and CHTO. The generalized surface wave inversion technique was applied to these group velocity dispersion data to determine the S-wave velocity structures of the crust and upper mantle for various regions of southeastern China. The results clearly demonstrate that the crust and upper mantle under southeastern China are laterally heterogeneous. The southern China region south of 25°N and the eastern China region both have a crustal thickness of 30 km. The eastern Tibet plateau along the 100°E meridian has a crustal thickness of 60 km. Central China, consisting mainly of the Yangtze and Sino-Korean platforms, has a crustal thickness of 40 km. A distinct S-wave low-velocity layer at 10–20 km depth in the middle crust was found under wave paths in southeastern China. On the other hand, no such crustal low-velocity layer is evident under the eastern Tibet plateau. This low-velocity layer in the middle crust appears to reflect the presence of a sialic low-velocity layer perhaps consisting of intruded granitic laccoliths, or possibly the remnant of the source zone of widespread magmatic activities known to have taken place in these regions since the late Carboniferous.  相似文献   

19.
For the last three decades, Northern China has been considered as one of the most sensitive areas regarding global environmental change. The integration of AVHRR GIMMS and MODIS NDVI data (1982–2011), of which for the overlapping period of 2000–2006 show good consistency, were used for characterizing land condition variability. The trends of standardized annually ΣNDVI, temperature, precipitation and PDSI were obtained using a linear regression model. The results showed that Northern China has a general increase in greenness for the period 1982–2011 (a = 0.05). Also, annually ΣNDVI is significantly correlated with temperature and precipitation data at the regional scale (p < 0.05), implying that temperature and precipitation are the dominant limiting factors for vegetation growth. Since the greening is not uniform, factors other than temperature and precipitation may contribute to greening in some areas, while the grassland and cropland ecosystem are becoming increasingly vulnerable to drought. The results of trend analysis indicate that greenness seems to be evident in most of the study areas.  相似文献   

20.
Studying climate changes over the past 2 000 years has important scientific significance in exploring climate variability on decadal to centennial timescales, assessing the natural and anthropogenic contribution to the climate warming, and understanding the effects of human activities in the past and future climate changes. Due to the scarcity of observation and uncertainty of reconstruction in this period, climate model is developed as a useful tool for studying paleoclimate.The Community Earth System Model (CESM) is one of the state-of-the-art climate models, but its performance in simulating the temperature in China has not been examined.The temperature datasets of observation/reanalysis (GHCN_CAMS) and reconstructions during the past 2000 years in China were used to examine the performance of CESM. The comparison between the annual average temperatures of GHCN_CAMS reanalysis and simulation showed that the model well reproduced the spatial distributions and upward trend of the annual average temperature in China, and the comparison with reconstructions in five sub-regions of China indicated that the simulation were in good consistent with the average temperature changes of reconstructionson decadal time scales. On the centennial time scale, the average temperature fluctuations of simulation in the regions of China were in accord with reconstructions generally except for Central East and Tibet.There existed three warm periods of simulated temperature variation in China over the past 2000 years, including 0-540AD, 800-1250AD and 1901-2000AD, and two cold periods involving the 551-721AD and 1400-1850AD, which had some discrepancies with reconstructions. And the discrepancies between simulation and reconstructions might be related to uncertainties of the resolution, external forcing and parameterization of the subgrid-scale process in the model.  相似文献   

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