Gas-particle partitioning of atmospheric reactive mercury and its contribution to particle bound mercury in a coastal city of the Yangtze River Delta, China

Ningbo is a major coastal city in the Yangtze River Delta region, China, with the largest cargo capacity in the world. We conducted a field campaign in Ningbo to measure the impact of the COVID-19 lockdown on air pollutants including NO2, O3 and CO from 21 January to 23 March 2020, using a home-made low-cost sensor package. The average concentrations of NO2, O3 and CO were observed to be 7.2, 37.5 and 648.5 ppb, respectively, during the lockdown. Compared with the previous year, the concentrations of NO2 and CO decreased by 63.1% and 6.9%, while the concentration of O3 increased by 37.9%. The significant reduction of NO2 concentration may be attributed to the reduced emissions of freighters and heavy trucks with lower port cargo throughput, which led to a decrease of NO concentration. The increase of O3 concentration was probably due to the lower titration of O3 by NO. After the lockdown, the concentrations of O3 and NO2 increased by 15.5% and 143.1%, respectively, compared with those during the lockdown. The temporal variations of the concentrations of NO2, O3 and CO measured by the sensor package were coincident with those obtained by the reference apparatus, which proves the sensor package to be suitable for air quality monitoring in field campaigns. This is the first time that a dramatic decrease in NO2 concentration in a coastal city due to a lockdown has been reported.

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Evaluating the energy efficiency of wastewater treatment plants in the Yangtze River Delta: Perspectives on regional discrepancies

Applied Energy ◽

10.1016/j.apenergy.2021.117087 ◽

2021 ◽

Vol 297 ◽

pp. 117087

Author(s):

Runyao Huang ◽

Ziheng Shen ◽

Hongtao Wang ◽

Jin Xu ◽

Zisheng Ai ◽

...

Keyword(s):

Energy Efficiency ◽

Wastewater Treatment ◽

Yangtze River ◽

Wastewater Treatment Plants ◽

Yangtze River Delta ◽

River Delta ◽

The Yangtze River ◽

The Yangtze River Delta

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Current Status and Temporal Trend of Potentially Toxic Elements Pollution in Agricultural Soil in the Yangtze River Delta Region: A Meta-Analysis

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18031033 ◽

2021 ◽

Vol 18 (3) ◽

pp. 1033

Author(s):

Shufeng She ◽

Bifeng Hu ◽

Xianglin Zhang ◽

Shuai Shao ◽

Yefeng Jiang ◽

...

Keyword(s):

Yangtze River ◽

Agricultural Soil ◽

Toxic Elements ◽

Temporal Trend ◽

Meta Analysis ◽

Yangtze River Delta ◽

Potentially Toxic Elements ◽

River Delta ◽

The Yangtze River ◽

The Yangtze River Delta

Potentially toxic elements (PTEs) pollution in the agricultural soil of China, especially in developed regions such as the Yangtze River Delta (YRD) in eastern China, has received increasing attention. However, there are few studies on the long-term assessment of soil pollution by PTEs over large regions. Therefore, in this study, a meta-analysis was conducted to evaluate the current state and temporal trend of PTEs pollution in the agricultural land of the Yangtze River Delta. Based on a review of 118 studies published between 1993 and 2020, the average concentrations of Cd, Hg, As, Pb, Cr, Cu, Zn, and Ni were found to be 0.25 mg kg−1, 0.14 mg kg−1, 8.14 mg kg−1, 32.32 mg kg−1, 68.84 mg kg−1, 32.58 mg kg−1, 92.35 mg kg−1, and 29.30 mg kg−1, respectively. Among these elements, only Cd and Hg showed significant accumulation compared with their background values. The eastern Yangtze River Delta showed a relatively high ecological risk due to intensive industrial activities. The contents of Cd, Pb, and Zn in soil showed an increasing trend from 1993 to 2000 and then showed a decreasing trend. The results obtained from this study will provide guidance for the prevention and control of soil pollution in the Yangtze River Delta.

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The Evolution of the Interactive Relationship between Urbanization and Land-Use Transition: A Case Study of the Yangtze River Delta

Land ◽

10.3390/land10080804 ◽

2021 ◽

Vol 10 (8) ◽

pp. 804

Author(s):

Bo Niu ◽

Dazhuan Ge ◽

Rui Yan ◽

Yingyi Ma ◽

Dongqi Sun ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Yangtze River ◽

Yangtze River Delta ◽

River Delta ◽

Socioeconomic Factor ◽

The Yangtze River ◽

Land Use Transition ◽

The Yangtze River Delta ◽

Interaction Relationship

In recent years, the impact of land-use systems on global climate change has become increasingly significant, and land-use change has become a hot issue of concern to academics, both within China and abroad. Urbanization, as an important socioeconomic factor, plays a vital role in promoting land-use transition, which also shows a significant spatial dependence on urbanization. This paper constructs a theoretical framework for the interaction relationship between urbanization and land-use transition, taking the Yangtze River Delta as an example, and measures the level of urbanization from the perspective of population urbanization, economic urbanization and social urbanization, while also evaluating the level of land-use morphologies from the perspective of dominant and recessive morphologies of land-use. We construct a PVAR model and coupled coordination model based on the calculated indexes for empirical analysis. The results show that the relationship between urbanization and land-use transition is not a simple linear relationship, but tends to be complex with the process of urbanization, and reasonable urbanization and land-use morphologies will promote further benign coupling in the system. By analyzing the interaction relationship between urbanization and land-use transition, this study enriches the study of land-use change and provides new pathways for thinking about how to promote high-quality urbanization.

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