Environmental fate of combustion-derived organic compounds in arid, urban soils in central Arizona-Phoenix
Author(s):
- Sharon Hall, Arizona State University
- Yevgeniy Marusenko, ASU
Abstract:
In this research we wanted to ask, what is the magnitude, distribution, and fate of non-point carbon pollution in a low-density, urban area? To answer this question, the goal of the project is to: 1) characterize and quantify combustion-derived carbon compounds in soils near roadways across the Phoenix valley, 2) explore the dynamic fate of Polycyclic Aromatic Hydrocarbons (PAHs) in soils, and 3) assess the importance of microbial community structure in PAH storage and dynamics. We collected 63 soil samples near highways across the Phoenix valley to characterize and quantify PAH compounds using extraction methods with Ultrasound Sonication and analyses by Gas Chromatography-Mass Spectrometry (GC-MS). Additionally, we measured a suite of soil properties and processes to explore the role of abiotic and biotic factors on the retention of PAHs in urban soil.
PAH concentrations in arid Phoenix soils ranged from 52 ug/kg dry soil to 8,296 ug/kg (mean 926 ug/kg), nearly an order of magnitude lower on average than expected based on data from other cities (Figure 1, Table 1). The project findings show the extent of these pollutants, an EPA-priority group of hazardous compounds, in urban soils. Although the most likely sources for PAH content in roadway soils are vehicle emissions, they were not correlated with traffic density (r2 = 0.024; p = 0.26) or highway age (r2 = 0.044; p = 0.13) across all sites. However, PAH concentrations were significantly correlated to soil organic matter (r2 = 0.36; p less than 0.001). These results suggest that PAH concentrations in roadway soils of desert cities may be controlled by factors associated with carbon retention, such as soil organic matter, rather than source or rate of deposition
Keywords:
Temporal Coverage:
2008-06-01 to 2009-06-01Geographic Coverage:
Geographic Description: Phoenix metropolitan areaBounding Coordinates:
Longitude:-112.31800 to -111.76300
Latitude:33.66090 to 33.26760
Contact:
Information Manager, Global Institute of Sustainability, Arizona State University,POB 875402,TEMPE
caplter.data@asu.edu
Methods used in producing this dataset: Show
Data Files (2) :
Tabular: 312_sites_1.csv
Description: Description and location of study sites
Column | Description | Type | Units |
---|---|---|---|
ID | Automatically generated sequential record
id |
integer | |
site_id | Site ID used in study |
string | |
road1 | Major road at intersection or ramp |
string | |
road2 | Major road at intersection or ramp |
string | |
adot_mile_marker | Arizona Department of Transportation (ADOT) mile
marker |
float | |
latitude | latitude |
float | |
longitude | longitude |
float | |
side_road | which side of the road the sample was
taken |
string | |
highway_section | highway section from which the sample was
taken |
string | |
traffic_density | traffic density according to ADOT
surveys |
float | |
age_highway | age of highway according to ADOT |
float | |
site_description | combined fields for human readability |
string |
Tabular: 312_soil_chemistry_1.csv
Description: Soil chemistry, PAH, nutrients
Column | Description | Type | Units |
---|---|---|---|
ID | Automatically generated sequential record id
number |
integer | |
site_id | Site id as used in sites table |
string | |
pH | ph of soil solution |
float | dimensionless |
soil_moisture | Soil moisture in percent |
float | dimensionless |
soil_org_matter | Soil organic matter content in
percent |
float | dimensionless |
water_hold_cap | Soil water holding capacity in
percent |
float | dimensionless |
no3_n | Nitrate concentration in micro gram per gram dry
soil |
float | microgramPerGram |
nh4_n | Ammonia concentration in micro gram per gram dry
soil |
float | microgramPerGram |
net_n_min | Nitrogen mineralization in microgram per gram dry soil and
day |
float | microgramPerGramPerDay |
net_nitrate | Net Nitrification in microgram per gram dry soil and
day |
float | microgramPerGramPerDay |
low_mol_weight | Low Molecular Weight less= 192, 2 or 3 rings (13 PAHs)
concentration (ug/kg) |
float | microgramPerKilogram |
med_mol_weight | Medium Molecular Weight greater= 202 4,5, or 6 (13 PAHs)
concentration (ug/kg) |
float | microgramPerKilogram |
high_mol_weight | Medium Molecular Weight greater= 252 (8 PAHs) concentration
(ug/kg) |
float | microgramPerKilogram |
naphthalene | Naphthalene concentration (ug/kg) |
float | microgramPerKilogram |
2_methylnaphthalene | 2-Methylnaphthalene concentration (ug/kg) |
float | microgramPerKilogram |
1_methylnaphthalene | 1-Methylnaphthalene concentration (ug/kg) |
float | microgramPerKilogram |
acenaphthylene | Acenaphthylene concentration (ug/kg) |
float | microgramPerKilogram |
acenaphthene | Acenaphthene concentration (ug/kg) |
float | microgramPerKilogram |
fluorene | Fluorene concentration (ug/kg) |
float | microgramPerKilogram |
phenanthrene | Phenanthrene concentration (ug/kg) |
float | microgramPerKilogram |
anthracene | Anthracene concentration (ug/kg) |
float | microgramPerKilogram |
3_me_phenanthrene | 3- me phenanthrene concentration (ug/kg) |
float | microgramPerKilogram |
2_me_phenanthrene | 2- me phenanthrene concentration (ug/kg) |
float | microgramPerKilogram |
3_me_anthracene | 3- me anthracene concentration (ug/kg) |
float | microgramPerKilogram |
9_me_phenanthrene | 9- me phenanthrene concentration (ug/kg) |
float | microgramPerKilogram |
1_me_phenanthrene | 1- me phenanthrene concentration (ug/kg) |
float | microgramPerKilogram |
fluoranthene | Fluoranthene concentration (ug/kg) |
float | microgramPerKilogram |
acephenanthrylene | Acephenanthrylene concentration (ug/kg) |
float | microgramPerKilogram |
pyrene | Pyrene concentration (ug/kg) |
float | microgramPerKilogram |
benz_a_anthracene | Benz(a)anthracene concentration (ug/kg) |
float | microgramPerKilogram |
chrysene | Chrysene concentration (ug/kg) |
float | microgramPerKilogram |
benzo_k_b_fluoranthene | Benzo (k+b) fluoranthene concentration (ug/kg) |
float | microgramPerKilogram |
benzo_j_fluoranthene | Benzo(j)fluoranthene concentration (ug/kg) |
float | microgramPerKilogram |
benzo_e_pyrene | Benzo(e)pyrene concentration (ug/kg) |
float | microgramPerKilogram |
benzo_a_pyrene | Benzo(a)pyrene concentration (ug/kg) |
float | microgramPerKilogram |
perylene | Perylene concentration (ug/kg) |
float | microgramPerKilogram |
indeno_123_cd_pyrene | Indeno(1,2,3)cd pyrene concentration (ug/kg) |
float | microgramPerKilogram |
dibenzo_ah_anthracene | Dibenzo(ah)anthracene concentration (ug/kg) |
float | microgramPerKilogram |
benzo_ghi_perylene | Benzo(ghi)perylene concentration (ug/kg) |
float | microgramPerKilogram |