Suchergebnisse

The ambient air quality of Guangzhou in 2016 has significantly improved since Guangzhou and its surrounding cities implemented a series of air pollution control measures from 2014 to 2016. This study not only estimated the effects of meteorology and emission control measures on air quality improvement in Guangzhou but also assessed the contributions of emissions reduction from various sources through the combination of observation data and simulation results from Weather Research and Forecasting - Community Multiscale Air Quality (WRF-CMAQ) modeling system. Results showed that the favorable meteorological conditions in 2016 alleviated the air pollution. Compared to change in meteorology, implementing emission control measures in Guangzhou and surrounding cities was more beneficial for air quality improvement, and it could reduce the concentrations of SO(2), NO(2), PM(2.5), PM(10), and O(3) by 9.7 μg m(−3) (48.4%), 9.2 μg m(−3) (17.7%), 7.7 μg m(−3) (14.6%), 9.7 μg m(−3) (13.4%), and 12.0 μg m(−3) (7.7%), respectively. Furthermore, emission control measures that implemented in Guangzhou contributed most to the concentration reduction of SO(2), NO(2), PM(2.5), and PM(10) (46.0% for SO(2), 15.2% for NO(2), 9.4% for PM(2.5), and 9.1% for PM(10)), and it increased O(3) concentration by 2.4%. With respect to the individual contributions of source emissions reduction, power sector emissions reduction showed the greatest contribution in reducing the concentrations of SO(2), NO(2), PM(2.5), and PM(10) due to the implementation of Ultra-Clean control technology. As for O(3) mitigation, VOCs product-related source emissions reduction was most effective, and followed by transportation source emissions reduction, while the reductions of power sector, industrial boiler, and industrial process source might not be as effective. Our findings provide scientific advice for the Guangzhou government to formulate air pollution prevention and control policies in the future.

The laurel family within the Magnoliids has attracted attentions owing to its scents, variable inflorescences, and controversial phylogenetic position. Here, we present a chromosomelevel assembly of the Litsea cubeba genome, together with low-coverage genomic and transcriptomic data for many other Lauraceae. Phylogenomic analyses show phylogenetic discordance at the position of Magnoliids, suggesting incomplete lineage sorting during the divergence of monocots, eudicots, and Magnoliids. An ancient whole-genome duplication (WGD) event occurred just before the divergence of Laurales and Magnoliales; subsequently, independent WGDs occurred almost simultaneously in the three Lauralean lineages. The phylogenetic relationships within Lauraceae correspond to the divergence of inflorescences, as evidenced by the phylogeny of FUWA, a conserved gene involved in determining panicle architecture in Lauraceae. Monoterpene synthases responsible for production of specific volatile compounds in Lauraceae are functionally verified. Our work sheds light on the evolution of the Lauraceae, the genetic basis for floral evolution and specific scents. ; The Fundamental Research Funds of Chinese Academy of Forestry, China; the Science and Technology Major Program on Agricultural New Variety Breeding of Zhejiang, China; the Ten Thousand People Plan of Science and Technology Innovation Leading Talent of Zhejiang, China; the National Key R&D Program of China; the Special Research Fund of Ghent University; the National Key Research and Development Program of China; the Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization Construction Funds and the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Program. ; http://www.nature.com/ncomms ; am2021 ; Biochemistry ; Genetics ; Microbiology and Plant Pathology