Search

In this study, sediment samples from the 4 regions of Lake Taihu Basin were collected to analyze the distribution characteristics, potential risks and possible sources of heavy metal pollution (Cr, Cu, Zn, As, Cd, Pd and Hg). The results showed that the concentrations and risks from heavy metals were lower in 2018 than in 2012, while the average concentrations of the 7 heavy metals were lower than the upper chemical exceedance level (UCEL). Spatially, the contents were higher in the eastern plains and Yangtze Riverside regions. The results of the risk assessment indicated that all heavy metals other than Cd were at low-pollution levels. In contrast, Cd showed high risk (Eir 255.425 in 2012, Eir 149.293 in 2018), which led to the high comprehensive potential ecological risk level in the western hilly region in 2012. In 2018, the risk for the entire Lake Taihu Basin decreased to a moderate level. In addition, the results of principal component analysis showed that Zn mainly originated from agriculture and zinc ore, Cd originated from metallurgical industries and pesticides, portions of Cu and Cr may have come from natural sources, and the other portions and other heavy metals mostly came from chemical industries such as electroplating. This study thoroughly analyzed the heavy metal pollution status of the Lake Taihu Basin surface sediments and provided a scientific basis for preventing and controlling water pollution in the region. [ABSTRACT FROM AUTHOR]

The rapid advancement of industrialization and urbanization has caused air pollution and increased the pressure on the urban ecological environment. Meanwhile, the unreasonable energy structure, emissions of pollution sources by chemical enterprises, and motor vehicle exhaust have aggravated the air pollution in urban areas. To analyse the temporal and spatial variation characteristics of air pollution and propose specific prevention and control measures for air pollution, taking Anhui Province in China as an example, this study analyses the causes of air pollution by using the air pollution index (API) data of Anhui Province obtained from 2013 to 2015. A comparative analysis is conducted on the API data from 2013 to 2015, and air quality in different cities of Anhui Province in 2015 is evaluated. Results show that unreasonable energy structure, accelerated urban infrastructure construction, and increasing motor vehicle emissions are the main cause of air pollution in Anhui Province. From temporal and spatial perspectives, the average APIs of different cities in Anhui Province from 2013 to 2015 were 64.8, 73.2 and 70.8 respectively. These values reveal the overall fluctuating growth trend of air pollution. From the spatial perspective, the number of days with good air quality in 14 cities of Anhui Province in 2015 ranged from 262 days to 365 days, which accounted for 71.8% to 100% of the total days in a year. It reflects that the degree of urban air pollution in northern Anhui is higher than that in southern Anhui. The conclusions reveal the temporal and spatial variation characteristics of air pollution, and provide policy suggestions for formulating scientific air pollution control measures, effectively implementing air pollution management and improving the current air pollution status. [ABSTRACT FROM AUTHOR]

Abstract: A high-resolution regional black carbon (BC) and organic carbon (OC) emission inventory for the year 2009 was developed for the Pearl River Delta (PRD) region, China, based on the collected activity data and the latest emission factors. PM2.5, BC and OC emissions were estimated to be 303kt, 39kt and 31kt, respectively. Industrial processes were major contributing sources to PM2.5 emissions. BC emissions were mainly from mobile sources, accounting for 65.0%, while 34.1% of OC emissions were from residential combustion. The primary OC/BC ratios for individual cities in the PRD region were dependent on the levels of economic development due to differences in source characteristics, with high ratios in the less developed cities and low ratios in the central and southern developed areas. The preliminary temporal profiles were established, showing the highest OC emissions in winter and relatively constant BC emissions throughout the year. The emissions were spatially allocated into grid cells with a resolution of 3km×3km. Large amounts of BC emissions were distributed over the central–southern PRD city clusters, while OC emissions exhibited a relatively even spatial distribution due to the significant biomass burning emissions from the outlying area of the PRD region. Uncertainties in carbonaceous aerosol emissions were usually higher than in other primary pollutants like SO2, NOx, and PM10. One of the key uncertainty sources was the emission factor, due to the absence of direct measurements of BC and OC emission rates. [Copyright &y& Elsevier]