Source particulate organic

Particulate organic matter LF — 2-18% of organic C, 1-16% of total N SSF - 20 45% of organic C and 13-40% of total N Partially decomposed plant litter isolated by density fractionation (LF) or sieving (SSF). Substrate and centre for soil microbial activity, short-term reservoir of nutrients, food source for earthworms and other soil fauna and focci for formation of water stable aggregates. 

Dalsey, J. M. Knelp, T. J. "Atmospheric Particulate Organic Matter Multivariate Models for Identifying Sources and Estimating Their Contributions to the Ambient Aerosol", This Symposium. 

Multivariate regression models have been developed for apportioning the contributions of emission sources to airborne particulate organic matter. 

The samples were analyzed for trace metals and sulfate as well as for three fractions of particulate organic matter (POM) using sequential extraction with cyclohexane (CYC), dichloromethane (DCM) and acetone (ACE). Factor analysis was used to identify the principal types of emission sources and select source tracers. Using the selected source tracers, models were developed of the form POM = a(V) + b(Pb) + - - -, where a and b are regression coefficients determined from ambient data adjusted to constant dispersion conditions. The models for CYC and ACE together, which constitute 90% of the POM, indicate that 40% (3.0 pg/m ) of the mass was associated with oil-burning, 19% (1.4 pg/m ) was from automotive and related sources and 15% (1.1 pg/m ) was associated with soil-like particles. 

Although the ultimate source of much of particulate organic matter (POM) in the urban aerosol appears to be fossil fuel a specific knowledge of the amounts and classes of organic compounds contributed by various types of sources is lacking. Estimates of source contributions have been based on emission inventories which have been largely directed toward polycyclic aromatic hydrocarbons and/or benzo(a)pyrene. There has been very little work on the development of mathematical and statistical models for POM source identification and allocation (1). In view... 

Multiple Regression Source Apportionment Models for Airborne Particulate Organic Matter in New York City... 

SOURCE APPORTIONMENT MODELS FOR CYCLOHEXANE-SOLUBLE PARTICULATE ORGANIC MATTER ... 

TSP added for soil resuspension ( ), then oil-burning, transportation, soil resuspension and other sources (such as incineration) can be estimated as contributing 57%, 24%, 15% and 4% of the primary TSP in New York City, respectively. The relative contributions of these sources to POM, i.e., the sum of CYC and ACE, from equations (14) and (18) are shown in Table VIII. Assuming that particulate organic matter is approximately proportional to TSP, the agreement in estimated relative source contributions is quite reasonable. 

Multivariate source. apportionment models have been developed for two fractions of respirable particulate organic matter which together constitute about 90% of the total organic solvent-extractable mass. The independent variables used for developing the models were trace metals, water-soluble sulfate and meteorological variables. Two of the three POM fractions extracted sequentially with cyclohexane (CYC), dlchloromethane (DCM) and acetone (ACE) were used as individual dependent variables. 

Zweidinger, R. B., R. K. Stevens, C. W. Lewis, and H. Westburg, Identification of Volatile Hydrocarbons as Mobile Source Tracers for Fine-Particulate Organics, Environ. Sci. Technol., 24, 538-542 (1990). 

PMF has successfully been applied to data from aerosol mass spectrometers (AMS, Aerodyne Research Inc., Billerica) for identification of the main sources of particulate organic matter, OM [9,12, 39], AMS instruments allow measurement of the mass spectra of the non-refractory fraction of approximately PM1 with high temporal resolution and determination of the concentration of particulate OM, which can be converted to OC by multiplication by a conversion factor [40]. 

Baron, J., D. M. McKnight, and A. S. Denning. 1991. Sources of dissolved and particulate organic material in Loch Vale Watershed, Rocky Mountain National Park, Colorado, USA. Biogeochemistry 15 89—110. 

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