[Effects of Vermicomposting on Compost Quality and Heavy Metals：A Meta-analysis].

In order to comprehensively evaluate the effects of vermicomposting on compost quality and the conversion of heavy metals under different control conditions, 109 studies were reviewed. The effects of earthworm species, pre-compost time, ventilation methods, initial C/N, initial pH, and initial moisture of the raw materials on compost quality and the heavy metal toxicity were quantitatively discussed during the vermicomposting process through Meta-analysis. The results showed that the six subgroups of factors all showed obvious influences on the compost quality and heavy metal toxicity.

[Characteristics and Source Analysis of Carbonaceous Aerosols in PM in Huaxi District, Guiyang].

Carbonaceous aerosol, as an important component of atmospheric aerosol, has a significant impact on atmospheric environmental quality, human health, and global climate change. To investigate the characteristics and sources of carbonaceous aerosol in atmospheric fine particulate matter (PM) in Huaxi District of Guiyang, an in-situ observational study was conducted during different seasons in 2020, and the carbonaceous components of PM were measured using a thermal-optical carbon analyzer (DRI Model 2015). The results of the study showed that the average concentrations of PM, total carbonaceous aerosol (TCA), organic carbon (OC), secondary organic carbon (SOC), and elemental carbon (EC) concentrations during the observation period were (39.

[Seasonal Variations and Source Apportionment of Carbonaceous Components in Luoyang: Implication for Brown Carbon Contribution].

A total of 98 samples were collected to analyze the seasonal variation and source apportionment of carbonaceous components, especially brown carbon (BrC), of PMin Luoyang during 2018-2019. The concentrations of organic carbon (OC) and elemental carbon (EC) ranged from (7.04±1.

[Characteristics of Carbonaceous Species in PM in Southern Beijing].

To investigate the characteristics of carbonaceous species in PM in Beijing after the implementation of the Action Plan for the Prevention and Control of Air Pollution, PM was continuously sampled in the heavily polluted southern urban area of Beijing from December 2017 to December 2018. The characteristics of organic carbon (OC) and element carbon (EC) were then determined. The results showed that the annual concentrations of PM, OC, and EC in Beijing varied in wide ranges of 4.

[Characteristics of Water-soluble Inorganic Ions in PM in Beijing During 2017-2018].

To explore the characteristics of water-soluble inorganic ions (WSIIs) in PM during the process of continuous improvement of air quality in Beijing in recent years, a continuous collection of PM sample campaign was conducted in Beijing from 2017 to 2018. The PM mass concentration and WSIIs were then determined. The results showed that the average concentration of PM in Beijing was (77.

[Analysis of Stable Carbon Isotope Characteristics of PM in Summer and Winter Season in Xinxiang City].

We study the seasonal variations of C ratios in aerosol fine particulate matter (PM) using 91 PM samples collected from Xinxiang, China, during the summer and winter in 2017. Mass concentrations of total carbon (TC), water soluble ions, and stable carbon isotope ratios (C) were determined. The mean concentrations of TC in the summer and winter were 11.

[Quantitative evaluation for separation of water-soluble and water-insoluble particulate matter on leaf surface of tree species: Taking five tree species as examples.].

To accurately and quantitatively evaluate the mass and particle size distribution of water-soluble and water-insoluble particulate matters (PM) on the surface of tree leaves, which would help to improve the accuracy of quantitative assessment of the retention ability of urban trees to atmospheric particles, we collected leaf samples from three broadleaved tree species [Ginkgo (Ginkgo biloba), Chinese scholar tree (Sophora japonica) and weeping willow (Salix babylonica)] and two conifer species [Chinese pine (Pinus tabuliformis) and China savin (Sabina chinensis)] 14 d after the rain (rainfall>15 mm). The PMs retained on leaves were collected by a succeeding procedure of washing + brushing (WC+BC) and ultrasonic cleaning (UC). Then, the extracts at each step were divided into water-soluble and water-insoluble PMs through centrifuge.

[Interannual Variation of Metal Elements and Water-Soluble Ions in PM During Wintertime in Xinxiang and Their Source Apportionment].

To study the interannual variations of chemical composition and source apportionment, a field campaign was carried out to collect the PM temperance sample during the winter of 2015 and the winter of 2016 in Xinxiang urban areas. PM mass concentration, metal elements, and the water-soluble ions were determined and meteorological factors were recorded simultaneously. The results showed that the daily mean concentrations of PM indicated serious pollution with values of 226 μg·m and 224 μg·m in 2015 and 2016, respectively.

[Seasonal Variation and Source Analysis of Water-soluble Inorganic Ions in Fine Particulate Matter in Zhengzhou].

In order to explore the characteristics of PM concentration and water-soluble inorganic ions in Zhengzhou City, a total of 170 PM samples were collected in the spring, summer, autumn, and winter seasons of 2016, with 30 days continuous sampling during each season. The mass concentration of PM was analyzed gravimetrically, water-soluble inorganic ions were determined by ion chromatography, and principle component analysis was employed for source apportionment. The results showed that the mass concentration of PM was 150.

[Particle Size Distribution and Human Health Risk Assessment of Heavy Metals in Atmospheric Particles from Beijing and Xinxiang During Summer].

Under a condition of good air quality (AQI:55-90, PM:37-97 μg·m, PM:17-76 μg·m), six groups of 54 samples were collected using an Andersen cascade impactor from both the indoor and outdoor stations in Beijing and Xinxiang from June to August in 2016. The samples were digested by microwave digestion, and nine heavy metal elements (Pb, Cr, Ni, Cu, Zn, As, Cd, Mn, and Co) in the atmospheric particles were determined with an inductively coupled plasma source mass spectrometer (ICP-MS). The results showed that the enrichment index (0-3) of most elements were low in both cities except for Cd[15.