Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls?

The effect of atmospheric aerosols and regional haze from air pollution on the yields of rice and winter wheat grown in China is assessed. The assessment is based on estimates of aerosol optical depths over China, the effect of these optical depths on the solar irradiance reaching the earth’s surface, and the response of rice and winter wheat grown in Nanjing to the change in solar irradiance. Two sets of aerosol optical depths are presented: one based on a coupled, regional climate/air quality model simulation and the other inferred from solar radiation measurements made over a 12-year period at meteorological stations in China. The model-estimated optical depths are significantly smaller than those derived from observations, perhaps because of errors in one or both sets of optical depths or because the data from the meteorological stations has been affected by local pollution. Radiative transfer calculations using the smaller, model-estimated aerosol optical depths indicate that the so-called “direct effect” of regional haze results in an ≈5–30% reduction in the solar irradiance reaching some of China’s most productive agricultural regions. Crop-response model simulations suggest an ≈1:1 relationship between a percentage increase (decrease) in total surface solar irradiance and a percentage increase (decrease) in the yields of rice and wheat. Collectively, these calculations suggest that regional haze in China is currently depressing optimal yields of ≈70% of the crops grown in China by at least 5–30%. Reducing the severity of regional haze in China through air pollution control could potentially result in a significant increase in crop yields and help the nation meet its growing food demands in the coming decades.

A Case Study of the Economic and Environmental Impacts from a Bio-fuel Facility (Southwest Georgia Ethanol, LLC) on the Surrounding Communities, Southwest Georgia

Bio-fuels such as ethanol provide an extraordinary opportunity to address our dependency on foreign oil. This case study examines the economic and environmental impacts associated with constructing and operating a dry mill ethanol manufacturing facility in a Southwest Georgia town and surrounding communities. The case study found that the plant had little impact on air quality, water quality, and habitat fragmentation. However, economic results showed the plant produced $1.5 million in tax revenues, and 86 jobs. Ethanol producers and communities must consider both the economic and environmental impacts on a local community when searching or attracting a bio-fuels plant. Likewise, communities should be aware of these challenges when attracting ethanol production plants.

An Investigation of Ozone Related Data and Development of a Model to Evaluate Ozone Episodes for Exceptional Event Criteria

The EPA promulgated the Exceptional Events Rule codifying guidance regarding exclusion of monitoring data from compliance decisions due to uncontrollable natural or exceptional events. This capstone examines documentation systems utilized by agencies requesting data be excluded from compliance decisions due to exceptional events. A screening tool is developed to determine whether an event would meet exceptional event criteria. New data sources are available to enhance analysis but evaluation shows many are unusable in their current form. The EPA and States must collaborate to develop consistent evaluation methodologies documenting exceptional events to improve the efficiency and effectiveness of the new rule. To utilize newer sophisticated data, consistent, user-friendly translation systems must be developed.

Atmospheric PM and volatile organic compounds released from Mediterranean shrubland wildfires

Wildfires produce a significant release of gases and particles affecting climate and air quality. In the Mediterranean region, shrublands significantly contribute to burned areas and may show specific emission profiles. Our objective was to depict and quantify the primary-derived aerosols and precursors of secondary particulate species released during shrubland experimental fires, in which fire-line intensity values were equivalent to those of moderate shrubland wildfires, by using a number of different methodologies for the characterization of organic and inorganic compounds in both gas-phase and particulate-phase. Emissions of PM mass, particle number concentrations and organic and inorganic PMx components during flaming and smouldering phases were characterized in a field shrubland fire experiment. Our results revealed a clear prevalence of K+ and SO42- as inorganic ions released during the flaming-smouldering processes, accounting for 68 to 80% of the inorganic soluble fraction. During the residual-smouldering phases, in addition to K+ and SO42-, Ca2+ was found in significant amounts probably due the predominance of re-suspension processes (ashes and soil dust) over other emission sources during this stage. Concerning organic markers, the chromatograms were dominated by phenols, n-alkanals and n-alkanones, as well as by alcohol biomarkers in all the PMx fractions investigated. Levoglucosan was the most abundant degradation compound with maximum emission factors between 182 and 261 mg kg-1 in PM2.5 and PM10 respectively. However, levoglucosan was also observed in significant amounts in the gas-phase. The most representative organic volatile constituents in the smoke samples were alcohols, carbonyls, acids, monocyclic and bicyclic arenes, isoprenoids and alkanes compounds. The emission factors obtained in this study may contribute to the validation and improvement of national and international emission inventories of this intricate and diffuse emission source.

A novel, bedside technique to rapidly identify umbilical cord blood units with high total nucleated cell numbers

BACKGROUND With increasing demand for umbilical cord blood units (CBUs) with total nucleated cell (TNC) counts of more than 150 × 10(7) , preshipping assessment is mandatory. Umbilical cord blood processing requires aseptic techniques and laboratories with specific air quality and cleanliness. Our aim was to establish a fast and efficient method for determining TNC counts at the obstetric ward without exposing the CBU to the environment. STUDY DESIGN AND METHODS Data from a total of 151 cord blood donations at a single procurement site were included in this prospective study. We measured TNC counts in cord blood aliquots taken from the umbilical cord (TNCCord ), from placenta (TNCPlac ), and from a tubing segment of the sterile collection system (TNCTS ). TNC counts were compared to reference TNC counts in the CBU which were ascertained at the cord blood bank (TNCCBU ). RESULTS TNCTS counts (173 ± 33 × 10(7) cells; calculated for 1 unit) correlated fully with the TNCCBU reference counts (166 ± 33 × 10(7) cells, Pearson's r = 0.97, p < 0.0001). In contrast, TNCCord and TNCPlac counts were more disparate from the reference (r = 0.92 and r = 0.87, respectively). CONCLUSIONS A novel method of measuring TNC counts in tubing segments from the sterile cord blood collection system allows rapid and correct identification of CBUs with high cell numbers at the obstetric ward without exposing cells to the environment. This approach may contribute to cost efficacy as only CBUs with satisfactory TNC counts need to be shipped to the cord blood bank.

Additional traffic assignment options for the TASSIM model. Phase I. Final report.

Transportation Department, Washington, D.C.

Human exposure model-II : user's guide.

Mode of access: Internet.

Control of particulate matter from oil burners and boilers /

Mode of access: Internet.

Social Security Administration District Office, Colorado Springs, Colorado.

Mode of access: Internet.

Development of a methodology for designing carbon monoxide monitoring networks /

Mode of access: Internet.

Pollution prevention research programs /

Mode of access: Internet.

Are you still holding your breath?

Mode of access: Internet.

TCM analyst 1.0 and user's guide.

Texas Department of Transportation, Austin

National Traffic Data Acquisition Conference (NATDAC '94). Proceedings, volume II. Final report.

Federal Highway Administration, Washington, D.C.

Automotive fuel economy contractors' coordination meeting - summary report.

Mode of access: Internet.