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Satellite derived NO column data have been used to study Chinese national fossil fuel consumption and pollutant emissions. Based on NO retrievals from two satellites (GOME and SCIAMACHY) for 1996-2010, we analyzed the characteristics and evolution of regional pollution related to NO emissions in China. Satellite observations indicated that the highly polluted regions were expanding. Anthropogenic emission dominated areas have expanded from the east to central and western China, and new highly polluted regions have formed throughout the nation. Bottom-up emission estimates suggested a 133% increase in anthropogenic NO emissions in East Central China during 1996 to 2010, which was lower than the 184% increase of the NO columns measured by the satellites. We found that growth rates of NO emissions have slowed in Chinese megacities over recent years, in contrast to which, the NO emissions were soaring in medium-sized cities, indicating that strict controls of NO emissions from coal-fired facilities are required in China. [ABSTRACT FROM AUTHOR]

The East Asian countries have been affected by atmospheric gaseous pollutants (in particular SO2) transported from the Asian continent as well as Asian dust storms. For investigation of the impact of these anthropogenic trace gases on local air quality in Korea, ground-based measurements using a Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) system and in situ gas analyzers as well as synoptic meteorological data and scattered sunlight spectra obtained by the satellite-borne instrument, Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) launched on board of Environmental Satellite (ENVISAT) in March 2002, were utilized to retrieve SO2 and trace its transport from the Asian continent to Korea in May 2005. The ground-based measurements were carried out in the region of interest, at Korea Global Watch Observatory (KGAWO) in Korea. Plumes of high SO2 over Chinese industrial areas and their transport to the Korean peninsula were observed in SCIAMACHY data in the period of 21–26 May 2005. Highly increased SO2 was measured by the MAX-DOAS system and in situ gas analyzer in the period of 27–29 May 2005 at KGAWO. These observations are supported by the meteorological results that the air-masses picking up these high SO2 plumes while passing over the Chinese industrial and metropolitan areas were transported to the Korean peninsula. The tropospheric SO2 VCDs over these Chinese industrial and metropolitan areas ranged up to 1.4×1017 molcm−2 in SCIAMACHY data. These SO2 plumes resulted in increased SO2 surface levels of up to 7.8ppbv (measured by an in situ gas analyzer) at KGAWO. [Copyright &y& Elsevier]

Long-term intensive cultivation in paddy soils strongly impacts soil pedogenesis and leads to accumulation of organic matter and the stratification of nutrients and oxygen in the soil profile. However, knowledge about the dynamics of soil microbial communities during continuous rice cultivation at long time scales including progressive and retrogressive stages is limited. In particular, the driving forces of community assembly also still remain poorly resolved. Therefore, we characterised the temporal and spatial changes in soil bacterial, fungal communities and functions using high-throughput sequencing and quantitative-PCR-based chip (targeting 64 microbial functional genes for C, N, P, S and methane metabolism) along a 2000‐year chronosequence of soils under paddy and adjacent non-paddy management in the Yangtze delta of China, a coastal region where paddy soils originated. Soil depth profiles were sampled from the paddy fields (6, 50, 100, 300, 700, 1000, and 2000 years of paddy use), the adjacent arable chronosequence (50, 100, 300 and 700 years of dryland use) and a tidal wetland (estuarine sediment, representing the parent material for paddy and arable soil reclamation). Results showed that across multiple time-scales ranging from decades to millennia, significant shifts in soil bacterial and fungal communities with soil depths occur, indicating paddy soil development and a microbial succession since reclamation from tidal wetlands. The initial stages of paddy and dryland soil development exhibited a higher phylogenetic ß-diversity than the soils at later successional states. Patterns of α‐diversity for microbial groups differed along soil chronosequence and with depth. Microbial α‐diversities in topsoil was greatest in soils of intermediate age, while the α‐diversities in subsoil was greatest in 1000-year cultivation. Moreover, allogenic succession of microbial communities was mostly driven by shifts in the soil physicochemical properties, especially pH and nutrient availability including organic matter and phosphorus during paddy soil development. Further network analysis showed that soil microbial communities were more interconnected at late successional stages than at initial stages, coinciding with a higher dymanics in turnover and environmental variability. Our study implies that, long-term rice cultivation substantially alters topsoil and subsoil microbial functional structure, leading to functional homogenization. Additionally, soil functions related to the acceleration of nutrient cycling, necessary for high crop yields, are promoted by long-term rice cultivation. [ABSTRACT FROM AUTHOR]

Abstract: Over the past few decades, China has experienced a rapid increase in urbanization. The urban built-up areas (population) in Beijing, Shanghai, and Guangzhou increased by 197% (87%), 148% (65%), and 273% (25%), respectively, from 1996 to 2011. We use satellite retrieval data to quantify the effects of rapid urbanization on the yearly and seasonal changes in tropospheric nitrogen dioxide (NO2) over East China. The results show that rapid urbanization has a profound effect on tropospheric columns of NO2. During 1996–2011, the tropospheric columns of NO2 over the surrounding areas of Guangzhou, Shanghai, and Beijing increased by 82%, 292%, and 307%, respectively. The tropospheric columns of NO2 reach their maximum in winter and minimum in spring. The anthropogenic emissions related to urbanization are a dominant factor in the long-term changes in the yearly and seasonal mean tropospheric columns of NO2, whereas meteorological conditions such as the prevailing winds and precipitation account for the unique spatial patterns. Around the time of the 2008 Beijing Olympic Games, the tropospheric columns of NO2 over Beijing urban area significantly reduced by 48% in July, 35% in August, and 49% in September, relative to the same monthly averages over 2005–2007. However, this trend was reversed after the Games, and the increased rate was even larger than before. Our results show that the tropospheric NO2 above the three regions increased at rates 1.3–8 times faster than the rates in a recent inventory estimate of NO x emissions for 2000–2010. We also discuss the influence of urbanization on tropospheric ozone and find that the Ozone Monitoring Instrument (OMI) retrieval tropospheric column shows that ozone levels are relatively insensitive to urbanization and changes in tropospheric NO2. [Copyright &y& Elsevier]

Abstract: A numerical analysis using a regional chemical transport model (CTM) is presented in comparison with Global Ozone Monitoring Experiment (GOME) and SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) satellite NO2 measurements over East Asia from 1996 to 2005 from a climatological perspective. Modeling results agree well with satellite retrievals in geographical distribution patterns, with systematic underestimation of the absolute values. The sharp increase in NO2 vertical column densities (VCDs) over central east China (CEC) after the year 2000 (14.1–20.5%yr−1 for the satellite observations and 10.8%yr−1 for model simulations) is analyzed quantitatively over different megacity clusters. The distinct emission increase patterns are responsible for the different increase trends observed over the Beijing megacity cluster (BJ), the Yangtze Delta (YD) and other CEC regions. The growth rate of satellite measured and CMAQ-modeled NO2 VCDs for the YD is much higher than that in other regions, with no clear seasonal variation. Apart from BJ and YD, NO2 emissions from other regions in CEC also expand considerably. [Copyright &y& Elsevier]