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Coal-dominated winter heating practices in China are largely accepted to be a leading cause of winter haze in the region though the amount of coal for heating is actually much lower than for power generation or industrial process. However, little is known about how the total rural coal weight in a region could be attributed to real time (e.g., daily) patterns, limiting the understanding of dynamic impacts of coal emissions and the adoption of timely measures against predicted haze. Considering that winter heating essentially protects against cold temperatures, coal burning strength may be related to the temperatures that people experience. A field study was organized to test the validity of this hypothesis. A system was designed to continuously monitor every instance of coal addition, and coal consumption on any given day for a whole village (WDAY) was calculated by summating all the additions. Meanwhile, a new term, composite temperature (TCOM), which incorporates a few weather-related elements, was introduced to represent cold temperatures that individuals experience. It was found that WDAY and TCOM presented opposite variations, and a negative linear correlation was observed (WDAY = −0.75TCOM + 11.86, R2 = 0.75), revealing the feasibility of estimating coal consumption on a certain day (WDAY) based on weather data (TCOM) for a given village. An extensive form of the algorithm for any area of interest (e.g., a district, city, or province) can be expressed as WDAY = (−0.75TCOM + 11.86)‧NH/834, where NH denotes the number of households in a region. This algorithm reflects the essence of winter heating (to resist cold temperatures), and therefore its logic is highly likely to be useful for any countries of the world regardless of what forms of energy used (coal or other energy forms) provided the energy involved is unexceptionally used for winter heating, though there may be some uncertainties in estimated coal consumption due to multiple factors.

The pollution characteristics of surfactant substances in fine particles (PM2.5) in spring were studied in the Beibu Gulf Region of China, 68 samples of PM2.5 were collected at Weizhou Island in Beihai City from March 12 to April 17, 2015. The Anionic Surfactant Substances (ASS) and Cationic Surfactant Substances (CSS) in the samples were analyzed using Byethyl Violet Spectrophotometry and Disulfide Blue Spectrophotometry, respectively. Combined with the data from backward trajectory simulation, the effects of air pollutants from remote transport on the pollution characteristics of surfactant substances in PM2.5 in the Beibu Gulf Region were analyzed and discussed. The results showed that the daily mean concentrations of ASS and CSS in spring in the Beibu Gulf Region were 165.20 pmol/m3 and 8.05pmol/m3, and the variation ranges were 23.21–452.55 pmol/m3 and 0.65–31.31 pmol/m3, accounting for 1.82‰ ± 1.65‰ and 0.12‰ ± 0.11‰ of the mass concentration of PM2.5, respectively. These concentrations were lower than those in comparable regions around the world. There was no clear correlation between the concentrations of ASS and CSS in PM2.5 and the mass concentrations of PM2.5. Tourism and air transport had a positive contribution on the concentrations of ASS. The concentration of surfactant substances in PM2.5 was significantly impacted by wind speed and wind direction. Atmospheric temperature, air pressure and precipitation had little effect on the concentrations of surfactant substances. Surfactant substances in PM2.5 significantly impacted visibility. Results also showed that the main sources of surfactant substances were from the southern China and Southeast Asia.

Catering oil fumes are a major hazard to human health. In particular, the typical Chinese cooking style is characterised by a high temperature frying process that produces high levels of cooking oil fumes. However, limited data relating to this sector mean that national emission inventory data specific to the catering service industry do not exist. To address above deficiency and thus to establish the inventory of a city, or a province, or even a country, a door-to-door survey campaign was launched in the Chinese cities of Heze and Linfen to determine the structure of local catering industries. Data revealed that the number of catering businesses per 104 people was 17 ± 4. Of these, 3.0 ± 1.4, 15.0 ± 1.4, and 82.0 ± 0.0% were classified as large, medium, and small enterprises, respectively. Furthermore, the installation rates of fume purifiers were 74 ± 13, 66 ± 9, and 51 ± 14% for large, medium, and small enterprises, respectively, with net removal efficiencies of 63 ± 11, 50 ± 7, and 31 ± 8%, respectively. This information was extrapolated across all provincial regions of China to construct a provincial and national emission inventory. In 2017, China's national catering industry released approximately 34 kt of volatile organic compounds (VOCs), 38 kt of particulate matter with a diameter less than 2.5 μm (PM2.5), 48 kt of particulate matter with a diameter less than 10 μm (PM10), 1 kt of black carbon (BC), and 27 kt of organic carbon (OC). A significant correlation was observed between vegetable oil consumption and emissions (e.g., for VOCs, y = 14.94 x + 76.50, R2 = 0.87, where y is VOCs emissions and x is vegetable oil consumption), indirectly corroborating the rationality of the inventory. Moreover, this correlation provides the potential for a dynamic inventory based on vegetable oil consumption. Future studies are proposed to address more influential factors to improve the reliability of the national inventory and refer to big data, rather than door-to-door investigation, to identify the amount of catering service businesses in a region.

In order to improve the regional air quality, many control strategies have been developed by Chinese government for reducing air pollutant emission from power plants, industrial and transport sources during the past decade. However, little attention has been paid to residential combustion sources. To fill the knowledge gap, a series of surveys were carried out to investigate the residential energy use in Beijing-Tianjin-Hebei (BTH) region during the period of 2013-2014. Study shows that the actual average amount of residential coal consumption is over 0.7tyr-1 per capita in 2013, which is much higher than that of 0.15tyr-1 per capita reported in the 2014 China Energy Statistical Yearbook (CESY). Combining the investigated activities data with the best available emission factors (EFs), bottom-up method was used to evaluate the potential air pollutant emissions from residential coal combustion in BTH region in 2013. The results indicate that Baoding is the top contributor to the whole BTH region and accounts for approximately 15% of the regional residential emissions in 2013. The spatial pattern of air pollutants shows that high emissions locate in the southeast, along the Yanshan and Taihang Mountains, where much more rural people live and coal combustion is prevalent in winter. The future emission scenario at the end of the 13th Five Year Plan (in 2020) was also predicted based on the policy guidance for the residential coal consumptions in the BTH region. The scenario analysis indicates that air pollutant emissions will drop substantially around 90% because more strict rules will be made for reducing the residential coal consumption. With combined survey information and statistical data, the uncertainty of the emission inventory which was established in this study for the residential sector in the BTH region is reduced and the emission inventory is more reliable for air quality decision making.

Along with the increasing concentration of nitrogenous pollutants emitted from the combustion and fertilizers, atmospheric nitrogen (N) deposition has become a great concern due to its significant ecological effect, especially in severe N emission regions such as the Yangtze River Delta (YRD) in east China. The spatial and temporal nitrate deposition fluxes were conducted using satellite data in YRD from 1996 to 2011. Our study reveals significant spatial variations of nitrate deposition in YRD region. In general, the fluxes of total (dry plus wet) nitrate deposition in YRD were up to 22.03 kg·N·ha-1·yr-1 with large loading received in winter. Most high fluxes appeared over urban (37.72 kg·N·ha-1·yr-1) and cropland (30.29 kg·N·ha-1·yr-1) areas. During the study period (1996–2011), a significant increasing trend of nitrate deposition was clearly observed in YRD with an annual rate of 1.33 kg·N·ha-1·yr-1. The spatial patterns of estimated nitrate deposition also showed that there were much higher fluxes and annual increasing trend in the middle region of YRD, i.e., the metropolitan areas contained Shanghai–Nanjing–Hangzhou cities, than in other areas. Our results also reveal that dry nitrate deposition contributed more than 50% of the total nitrate deposition over all provinces and land covers except coastal sea (14.27%), which indicates the relative importance of dry deposition to the total nitrate deposition in the YRD region. Therefore, it is necessary to consider both dry and wet deposition when evaluating the influences of nitrate deposition on environment and ecosystem health.