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Abstract: Emissions from burning major agricultural residue were measured through laboratory simulations using a self-designed dilution chamber system. Emission factors of CO2, CO, non-methane hydrocarbons (NMHCs), oxygenated volatile organic compounds (OVOCs), PM10, PM2.5, OC and EC in PM2.5 were measured for burning rice straw in flaming and smoldering combustion, and for burning of sugarcane leaves. NMHCs emitted from crop straw open burning were dominated by C2 hydrocarbons (ethene, ethane, ethyne), contributing (53.4 ± 4.6)% in volume in rice straw burning emissions and 41.8% in sugarcane burning emissions, respectively. Acetone and aldehyde were major OVOCs species in open straw burning emissions. A survey was conducted to determine the fraction of field crop biomass burned during harvesting season and the amounts of household firewood and crop residue consumption in 2008. Information obtained from the survey, together with measured EFs for field burning of rice straw and sugarcane, and EFs from literatures for field burning of other agricultural residues, biofuel combustion and forest fires, were used in developing the source inventories of carbonaceous pollutants in the PRD region. The annual emissions of CO, VOCs (including NMHCs and OVOCs), NO x , PM2.5, OC and EC from burning biomass were estimated to be 186.38, 15.94, 4.93, 15.56, 7.10, 2.25 kt in the year 2008, respectively. These estimates are lower than previously published estimates by 23–63%. Open burning patterns (flaming and smoldering) and rural biofuel use contribute to the differences. Field burning of straw contributed mainly to VOCs, PM2.5 and OC emissions while the residential sector was the dominant source of EC, CO and NO x . The contributions of biomass burning to entire PRD emissions are estimated as 3.37–6.53%, respectively, for PM, and 1.82–3.17%, respectively, for VOCs, and 0.52–2.77%, respectively, for NO x . [Copyright &y& Elsevier]

Abstract: In recent years, Mainland China, and in particular the industrial hotbed of the Pearl River Delta (PRD) has experienced an increasingly serious problem of high concentrations of airborne particulate matter. Following the tightening-up of China's air quality policies in recent years, and with especially fine particles now added to a new air quality objective, the identification of major source regions and major types of pollutants has become crucial. In this study, the Comprehensive Air Quality Model (CAMx), together with the Particulate Source Apportionment Technology (PSAT) source apportionment method, has been applied to analyze how different emission activities influence PM concentration in the PRD region. By using this method, a detailed source region and emission category contribution matrix is derived for all regions within the Hong Kong/PRD region and source appointment results show that, on average, for different cities super-regional transport and mobile vehicles are the two major fine particle sources, contributing 62% (34.3 μg m−3) and 21% (12.2 μg m−3) of the total figure in December, and 42% (13.1 μg m−3) and 28% (9.7 μg m−3) in April. Meanwhile, over the same period in Hong Kong, in addition to these two factors, marine proved another very significant source of particle pollutant, amounting to 18% of the total figure (4.7 μg m−3). Another important cause of high PM levels has been the transport of fine particles between cities within the PRD region, with three different regions selected for detailed analysis. Results show that for the Hong Kong/PRD region local reduction of mobile sources and collaboration between different areas could have succeeded in alleviating the air pollution problem. [Copyright &y& Elsevier]

Abstract: A new exhaust emission inventory of ocean-going vessels (OGVs) was compiled for Hong Kong by using Automatic Identification System (AIS) data for the first time to determine typical main engine load factors, through vessel speed and operation mode characterization. It was found that in 2007, container vessel was the top emitting vessel type, contributing 9,886, 11,480, 1,173, 521 and 1166 tonnes of SO2, NO x , PM10, VOC and CO, respectively, or about 80%–82% of the emissions. The top five, which also included ocean cruise, oil tanker, conventional cargo vessel and dry bulk carrier, accounted for about 98% of emissions. Emission maps, which add a new spatial dimension to the inventory, show the key emission hot spots in Hong Kong and suggest that a significant portion of emissions were emitted at berth. Scientific evidence about the scale and distribution of ship emissions has contributed in raising public awareness and facilitating stakeholder engagement about the issue. Fair Winds Charter, the world's first industry-led voluntary emissions reduction initiative, is a perfect example of how careful scientific research can be used in public engagement and policy deliberation to help drive voluntary industry actions and then government proposals to control and regulate marine emissions in Hong Kong and the Pearl River Delta region. [Copyright &y& Elsevier]