scholarly journals A Four-Dimensional Evaluation of the Urban Comprehensive Carrying Capacity of the Yangtze River Delta, China

2019 ◽  
Vol 11 (23) ◽  
pp. 6816 ◽  
Author(s):  
Qinglong Shao ◽  
Jiaying Li ◽  
Lingling Zhao
Keyword(s):  
Carrying Capacity ◽  
Yangtze River ◽  
Yangtze River Delta ◽  
River Delta ◽  
Policy Implications ◽  
The Other ◽  
The Yangtze River ◽  
The Yrd ◽  
The Yangtze River Delta ◽  
Comprehensive Carrying Capacity

The evaluation of urban comprehensive carrying capacity (UCC) is of great importance in maintaining urban socio-economic sustainable development. However, UCC is still in its nascent period with limited applications and a lack of credible assessment methods. To enrich this field, this study constructed an objective scientific index to evaluate the UCC of the Yangtze River Delta (YRD) region from a four-dimensional perspective, examining economy, society, environmental, and transportation subsystems. The improved entropy method based on 18 weighted indicators was used to measure the UCC of the 26 cities of the YRD for the period 1990–2018. Results indicate that nine cities were overloaded in 2018, meaning comprehensive carrying capacity demand exceeds supply, and the other seventeen were in loadable condition, meaning such demand did not exceed supply; the social and transportation subsystems are the most important because their index weights and UCC levels are higher than the other two subsystems; the overall UCC for all cities in the YRD is at a medium level, and there are large disparities between the various cities. The empirical results imply that the government should take effective measures to improve UCC in these cities, combining cities’ specific advantages to enhance the efficiency of resource allocation and utilization and improve carrying capacities, and changing the mode of economic development. Based on UCC levels, it is also important to improve environmental conditions and coordination and integration in the development of urbanization. Policy implications on improving UCC have been highlighted in the final section.

scholarly journals Genetic Relationships among 11 Nonheading Chinese Cabbage Accessions and the SCAR Marker Specific for ‘Suzhouqing’

HortScience ◽  
2018 ◽  
Vol 53 (9) ◽  
pp. 1288-1293
Author(s):  
Xuelin Shen ◽  
Yanmei Zhang ◽  
Zhao Lei ◽  
Yibo Lin ◽  
Minxu Cao ◽  
...  
Keyword(s):  
Chinese Cabbage ◽  
Genetic Relationship ◽  
Yangtze River ◽  
Scar Marker ◽  
Yangtze River Delta ◽  
River Delta ◽  
The Other ◽  
The Yangtze River ◽  
Relationship Analysis ◽  
The Yangtze River Delta

‘Suzhouqing’ is a unique landrace of nonheading Chinese cabbage [Brassica rapa var. chinensis (Linnaeus) Kitamura] with a long history of cultivation in Suzhou of Jiangsu Province, China. However, transitional and overlapped morphologic traits make it difficult to authenticate this accession from other nonheading Chinese cabbages. Genetic relationship between ‘Suzhouqing’ and the related 10 popular accessions in the Yangtze River Delta were analyzed using two well-studied single-copy nuclear genes—ARGONAUTES 7 (AGO7) and BcMF15; the molecular identification of ‘Suzhouqing’ was determined based on the intersimple sequence repeat–sequence-characterized amplified region (ISSR-SCAR) marker. The results indicated that ‘Suzhouqing’ could be identified specifically from the other 10 accessions based on 21 specific nucleotide variations of the AGO7 gene. Sequence variations show a strong correlation with leaf morphology, suggestive of partial causal links between the two. Genetic relationship analysis showed that five accessions with close geographic locations had a very close genetic relationship, whereas the genetic relationship of the other five accessions was related to their morphologic similarity. One exception, ‘AJH’, might undergo a special evolutionary process. Furthermore, ISSR-880 was screened as the specific primer to identify accession ‘Suzhouqing’, and a specific discrimination ISSR-SCAR marker was explored, which amplified no target band in any other accessions. The development of molecular markers for the specific identification of ‘Suzhouqing’ in 11 popular accessions in the Yangtze River Delta could provide a theoretical basis for the protective identification of other agricultural crops.

scholarly journals Integrating Sustainability Assessment into Decoupling Analysis: A Focus on the Yangtze River Delta Urban Agglomerations

2020 ◽  
Vol 12 (19) ◽  
pp. 7872
Author(s):  
Yijia Huang ◽  
Jiaqi Zhang ◽  
Jinqun Wu
Keyword(s):  
Environmental Sustainability ◽  
Yangtze River ◽  
Sustainability Assessment ◽  
Yangtze River Delta ◽  
River Delta ◽  
The Yangtze River ◽  
Urban Agglomerations ◽  
Decoupling Analysis ◽  
The Yrd ◽  
The Yangtze River Delta

Rapid urbanization has led to a growing number of environmental challenges in large parts of China, where the Yangtze River Delta (YRD) urban agglomerations serve as a typical example. To evaluate the relationship between environmental sustainability gaps and urbanization in 26 cities of the YRD, this study revisited the environmental sustainability assessment (ESA) by combining the metrics of environmental footprints and planetary boundaries at the city level, and then integrated the footprint-boundary ESA framework into decoupling analysis. The results demonstrated considerable spatiotemporal heterogeneity in the environmental sustainability of water use, land use, carbon emissions, nitrogen emissions, phosphorus emissions and PM2.5 emissions across the YRD cities during the study period 2007–2017. Decoupling analysis revealed a positive sign that more than half of the 26 cities had achieved the decoupling of each category of environmental sustainability gaps from urbanization since 2014, especially for nitrogen and phosphorus emissions. On the basis of ESA and decoupling analysis, all the cities were categorized into six patterns, for which the optimal pathways towards sustainable development were discussed in depth. Our study will assist policy makers in formulating more tangible and differentiated policies to achieve decoupling between environmental sustainability gaps and urbanization.

scholarly journals Integrated studies of a regional ozone pollution synthetically affected by subtropical high and typhoon system in the Yangtze River Delta region, China

2016 ◽  
Author(s):  
Lei Shu ◽  
Min Xie ◽  
Tijian Wang ◽  
Pulong Chen ◽  
Yong Han ◽  
...  
Keyword(s):  
Yangtze River ◽  
Western Pacific Subtropical High ◽  
Yangtze River Delta ◽  
River Delta ◽  
Western Pacific ◽  
Subtropical High ◽  
The Yangtze River ◽  
Observational Analysis ◽  
The Yrd ◽  
The Yangtze River Delta

Abstract. Severe high ozone (O3) episodes usually have close relations to synoptic systems. A regional continuous O3 pollution episode is detected over the Yangtze River Delta (YRD) region in China during August 7–12, 2013, in which the O3 concentrations in more than half of the cities exceeding the national air quality standard. The maximum hourly concentration of O3 reaches 167.1 ppb. By means of the observational analysis and the WRF/CMAQ numerical simulation, the characteristics and the essential impact factors of the typical regional O3 pollution is integratedly investigated. The observational analysis shows that the atmospheric subsidence dominated by Western Pacific subtropical high plays a crucial role in the formation of high-level O3. The favorable weather conditions, such as extremely high temperature, low relative humidity and weak wind speed, caused by the abnormal strong subtropical high are responsible for the trapping and the chemical production of O3 in the boundary layer. In addition, when the YRD cities at the front of Typhoon Utor, the periphery circulation of typhoon system can enhance the downward airflows and cause worse air pollution. But when the typhoon system weakens the subtropical high, the prevailing southeasterly surface wind leads to the mitigation of the O3 pollution. The Integrated Process Rate (IPR) analysis incorporated in CMAQ is applied to further illustrate the combined influence of subtropical high and typhoon system in this O3 episode. The results show that the vertical diffusion (VDIF) and the gas-phase chemistry (CHEM) are two major contributors to O3 formation. During the episode, the contributions of VDIF and CHEM to O3 maintain the high values over 10 ppb/h in Shanghai, Hangzhou, and Nanjing. On August 10–11, the cities close to the sea are apparently affected by the typhoon system, with the contribution of VDIF increasing to 28.45 ppb/h in Shanghai and 19.76 ppb/h in Hangzhou. When the YRD region is under the control of the typhoon system, the contribution values of all individual processes decrease to a low level in all cities. These results provide an insight for the O3 pollution synthetically impacted by the Western Pacific subtropical high and the tropical cyclone system.

scholarly journals Source, transport and impacts of a heavy dust event in the Yangtze River Delta, China in 2011

2013 ◽  
Vol 13 (8) ◽  
pp. 21507-21540
Author(s):  
X. Fu ◽  
S. X. Wang ◽  
Z. Cheng ◽  
J. Xing ◽  
B. Zhao ◽  
...  
Keyword(s):  
Air Quality ◽  
Yangtze River ◽  
Eastern China ◽  
Yangtze River Delta ◽  
River Delta ◽  
Dust Particles ◽  
The Yangtze River ◽  
Dust Event ◽  
The Yrd ◽  
The Yangtze River Delta

Abstract. During 1 to 6 May 2011, a dust event was observed in the Yangtze River Delta region (YRD). The highest PM10 concentration reached over 1000 μg m−3 and the visibility was below 3 km. In this study, the Community Multi-scale Air Quality modeling system (CMAQ5.0) coupled with an in-line windblown dust model was used to simulate the formation, spatial and temporal characteristics of this dust event, and analyze its impacts on deposition and photochemistry. The threshold friction velocity for loose smooth surface in the dust model was revised based on Chinese data to improve the model performance. The comparison between predictions and observations indicates the revised model can reproduce the transport and pollution of the event. The simulation results show that the dust event was affected by formation and transport of Mongolian cyclone and cold air. Totally about 695 kt dust particles (PM10) were emitted in Xinjiang Province and Mongolia during 28 to 30 April, the dust band swept northern, eastern China and then arrived in the YRD region on 1 May 2011. The transported dust particles increased the mean surface layer concentrations of PM10 in the YRD region by 372% during 1 to 6 May and the impacts weakened from north to south due to the removal of dust particles along the path. Accompanied by high PM concentration, the dry deposition, wet deposition and total deposition of PM10 in the YRD reached 184.7 kt, 172.6 kt and 357.32 kt, respectively. These deposited particles are very harmful because of their impacts on urban environment as well as air quality and human health when resuspending in the atmosphere. Due to the impacts of mineral dust on atmospheric photolysis, the concentrations of O3 and OH were reduced by 1.5% and 3.1% in the whole China, and by 9.4% and 12.1% in the YRD region, respectively. The work of this manuscript is meaningful for understanding the dust emissions in China as well as for the application of CMAQ in Asia. It is also helpful to understand the formation mechanism and impacts of dust pollution in the YRD.

scholarly journals Spatiotemporal distribution and trend of COVID-19 in the Yangtze River Delta region of the People’s Republic of China

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Lei Ye ◽  
Lingqian Hu
Keyword(s):  
Yangtze River ◽  
Yangtze River Delta ◽  
Hubei Province ◽  
River Delta ◽  
People’S Republic Of China ◽  
The Yangtze River ◽  
People's Republic Of China ◽  
Republic Of China ◽  
The Yrd ◽  
The Yangtze River Delta

An outbreak of atypical pneumonia, now called COVID-19 and known to be caused by the novel coronavirus SARS-CoV-2, first detected in Wuhan, Hubei Province of the People’s Republic of China in December 2019 and afterwards rapidly spread worldwide. Wuhan and the Yangtze River Delta (YRD) region implemented first-level public health emergency responses to stop the spread of the virus on January 23rd, 2020. We tracked the geographical gravity centre of the disease and calculated spatial autocorrelation to explore the spatiotemporal patterns of distribution of imported and locally disseminated COVID-19 cases under the emergency-response control measure. We also applied polynomial regression analysis to estimate the trend of the COVID-19 in the YRD region before and after the control activities against the spread of the infection were instituted. The results show that the control measures applied have been effective. And, in the YRD region, areas with a large influx of population flow from Wuhan and Hubei Province had high risks of COVID-19. Therefore, identification of the spatiotemporal trends should be the first step when developing effective policies to manage and control any new epidemic. The results are not only informative locally but also useful for the rest of the world.

scholarly journals Column and Surface Aerosol Optical Properties and Their Association with Meteorology in the Yangtze River Delta

2019 ◽  
Vol 8 (4) ◽  
pp. 8255-8259
Keyword(s):  
Optical Properties ◽  
Yangtze River ◽  
Negative Relationship ◽  
Yangtze River Delta ◽  
River Delta ◽  
The Yangtze River ◽  
Negative Effect ◽  
The Yrd ◽  
The Impact ◽  
The Yangtze River Delta

Aerosols played an important role in climate change during recent years in China. Many kinds of researches in different areas in China, particularly over the Yangtze River Delta (YRD) region in East China is measured during the period from January 2013 to December 2015. The Moderate Resolution Imaging Spectroradiometer (MODIS) derived aerosol optical depth (AOD), particulate matter concentrations (PM2.5) and surface black carbon (BCS) was used in this study. Nanjing, Hangzhou, Shanghai, and Ningbo have been selected in this research as they are the major cities of the YRD region that represents different environments. Variation of AOD550, Ångström exponent (AE470-660) and PM2.5 are mainly discussed, and meanwhile, the relationship that exists between them and with the meteorology is also discussed in this work. Apart from this, the impact of visibility and water vapor are also considered to examine the influence on optical properties. The data and analysis indicate that urban cities have a higher value of AOD than rural background cities. High AOD was noticed in summer than in other seasons. AOD usually has a negative relationship with AE, except in summer. Similarly, the PM2.5 has a negative relationship with AOD, whereas, BCS has a positive correlation with AOD. Further, it was observed that the rise in temperature resulted in high AOD concentration. The visibility has negative effect on AOD, whereas, AQI follows similar pattern as that of visibility.

scholarly journals The study of emission inventory on anthropogenic air pollutants and VOC species in the Yangtze River Delta region, China

2011 ◽  
Vol 11 (1) ◽  
pp. 951-983 ◽  
Author(s):  
C. Huang ◽  
C. H. Chen ◽  
L. Li ◽  
Z. Cheng ◽  
H. L. Wang ◽  
...  
Keyword(s):  
Air Pollutants ◽  
Yangtze River ◽  
Emission Inventory ◽  
Yangtze River Delta ◽  
River Delta ◽  
The Yangtze River ◽  
Voc Emissions ◽  
Anthropogenic Air Pollutants ◽  
The Yrd ◽  
The Yangtze River Delta

Abstract. The purpose of this study is to develop an emission inventory for major anthropogenic air pollutants and VOC species in the Yangtze River Delta (YRD) region for the year 2007. A "bottom-up" methodology was adopted to compile the inventory based on major emission sources in the sixteen cities of this region. Results show that the emissions of SO2, NOx, CO, PM10, PM2.5, VOCs, and NH3 in the YRD region for the year 2007 are 2391.8 kt, 2292.9 kt, 6697.1 kt, 3115.7 kt, 1510.8 kt, 2767.4 kt, and 458.9 kt, respectively. Ethylene, mp-xylene, o-xylene, toluene, and 1,2,4-trimethylbenzene, 2,4-dimethylpentane, ethyl benzene, propylene, 1-pentene, and isoprene are the key species contributing 77% to the total OFPs. The spatial distribution of the emissions shows the emissions and OFPs are mainly concentrated in the urban and industrial areas along the Yangtze River and around the Hangzhou Bay. The industrial sources including power plant, other fuel combustion facilities, and non-combustion processes contribute about 97%, 86%, 89%, 91%, and 69% of the total SO2, NOx, PM10, PM2.5, and VOC emissions. Vehicles take up 12.3% and 12.4% of the NOx and VOC emissions, respectively. Regarding OFPs, chemical industry, domestic use of paint and printing, and gasoline vehicle contribute 38.2%, 23.9%, and 11.6% to the ozone formation in the YRD region.

scholarly journals Nineteen Years of Trophic State Variation in Large Lakes of the Yangtze River Delta Region Derived from MODIS Images

2021 ◽  
Vol 13 (21) ◽  
pp. 4322
Author(s):  
Yingchun Bian ◽  
Ying Zhao ◽  
Heng Lyu ◽  
Fei Guo ◽  
Yunmei Li ◽  
...  
Keyword(s):  
Human Activities ◽  
Yangtze River ◽  
Trophic State ◽  
Yangtze River Delta ◽  
River Delta ◽  
Downward Trend ◽  
The Yangtze River ◽  
Large Lakes ◽  
The Yrd ◽  
The Yangtze River Delta

The Yangtze River Delta (YRD) is one of the regions with the most intensive human activities. The eutrophication of lakes in this area is becoming increasingly serious with consequent negative impacts on the water supply of the surrounding cities. But the spatial-temporal characteristics and driving factors of the trophic state of the lake in this region are still not clearly addressed. In this study, a semi-analytical algorithm for estimating the trophic index (TSI) using particle absorption at 645 nm based on MODIS images is proposed to monitor and evaluate the trophic state of 41 large lakes (larger than 10 km2) in the YRD from 2002 to 2020. The performance of the proposed algorithm is evaluated using an independent dataset. Results showed that the root-mean-square error (RMSE) of the algorithm is less than 6 and the mean absolute percentage error (MAPE) does not exceed 8%, indicating that it can be applied for remotely deriving the TSI in the YRD. The spatial-temporal patterns revealed that there were significantly more lakes with moderate eutrophication in the Lower Yangtze River (LYR) than in the Lower Huaihe River (LHR). The overall average value of the TSI reaches a maximum in summer and a minimum in winter. The TSI value in the YRD over the period 2002–2020 showed a downward trend, especially after 2013. Individually, 33 lakes showed a downward trend and 8 lakes showed an upward trend. Furthermore, marked seasonal and interannual temporal variations can be clearly observed in the LYR and LHR and the sum of the variance contributions of seasonal and interannual components is more than 50%. Multiple linear regression analysis showed that human activities can explain 65% of the variation in the lake TSI in the YRD.

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