Distribution and Source Apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) in Forest Soils from Urban to Rural Areas in the Pearl River Delta of Southern China
Abstract
:1. Introduction
2. Materials and Methods
2.1. Site Description and Soil Sampling
2.2. Chemicals and Materials
2.3. Sample Extraction
2.4. GC Analysis and Quantification
2.5. Quality Control
2.6. Statistical Analysis
3. Results and Discussion
3.1. PAH Concentrations
PAH | Urban | Suburban | Rural | ||||||
---|---|---|---|---|---|---|---|---|---|
Average | Min | Max | Average | Min | Max | Average | Min | Max | |
NAP | 20.42 | 7.18 | 34.04 | 19.20 | 10.41 | 29.29 | 13.77 | 8.59 | 22.87 |
ACY | 0.94 | 0.30 | 1.57 | 0.71 | 0.43 | 1.33 | 0.30 | 0.13 | 0.49 |
ACE | 0.92 | 0.18 | 4.10 | 0.86 | 0.54 | 1.39 | 0.41 | 0.25 | 0.53 |
FLO | 1.50 | 0.56 | 3.05 | 2.94 | 1.69 | 5.20 | 1.69 | 0.98 | 2.66 |
PHE | 14.05 | 0.66 | 30.98 | 15.48 | 6.51 | 41.04 | 7.01 | 3.87 | 13.57 |
ANT | 5.87 | 2.20 | 61.72 | 2.46 | 1.29 | 5.04 | 2.32 | 1.35 | 4.69 |
FLA | 22.77 | 7.86 | 94.72 | 7.27 | 2.31 | 32.97 | 2.01 | 1.05 | 4.49 |
PYR | 20.09 | 9.94 | 43.22 | 5.72 | 2.30 | 16.23 | 1.24 | 0.74 | 2.12 |
BaA | 6.54 | 1.98 | 18.72 | 2.41 | 0.88 | 6.30 | 1.07 | 0.42 | 3.69 |
CHR | 11.81 | 3.65 | 41.81 | 4.00 | 1.27 | 11.18 | 1.79 | 0.66 | 7.30 |
BbF | 13.44 | 2.25 | 69.87 | 4.80 | 0.94 | 12.44 | 1.85 | 0.43 | 11.40 |
BkF | 10.07 | 1.09 | 69.33 | 1.27 | 0.22 | 3.57 | 0.33 | 0.10 | 1.49 |
BaP | 4.59 | 0.95 | 29.67 | 1.14 | 0.19 | 2.74 | 0.27 | 0.07 | 0.74 |
IcdP | 9.32 | 1.21 | 66.43 | 2.82 | 0.68 | 9.36 | 0.94 | 0.28 | 3.29 |
DahA | 2.96 | 0.23 | 11.01 | 0.45 | 0.10 | 0.98 | 0.16 | 0.04 | 1.06 |
BghiP | 6.84 | 1.46 | 23.76 | 2.15 | 0.39 | 4.80 | 0.72 | 0.21 | 4.39 |
ΣPAHs a | 152.10 | 71.28 | 515.34 | 73.67 | 39.85 | 201.01 | 35.86 | 18.90 | 75.17 |
PAHs7 b | 58.72 | 13.63 | 279.47 | 16.88 | 4.88 | 51.93 | 6.41 | 2.11 | 28.72 |
PAHs7c/PAHs | 0.39 | 0.19 | 0.54 | 0.23 | 0.12 | 0.26 | 0.18 | 0.11 | 0.38 |
R3 ≤ /R ≥ 4 c | 0.41 | 0.14 | 1.53 | 1.30 | 0.41 | 2.33 | 2.46 | 0.38 | 3.34 |
3.2. PAH Profiles
3.3. Source Apportionment by Isomeric Ratios of PAHs
3.4. Source Identification by Principal Component Analysis
Site | Urban | Suburban | Rural | |||
---|---|---|---|---|---|---|
Principal component | PC1 | PC2 | PC1 | PC2 | PC1 | PC2 |
NAP | 0.86 | 0.91 | 0.82 | |||
ACY | 0.91 | 0.90 | 0.94 | |||
ACE | 0.88 | 0.81 | 0.98 | |||
FLO | 0.53 | 0.73 | 0.67 | 0.92 | ||
PHE | 0.57 | 0.69 | 0.74 | 0.70 | 0.61 | |
ANT | 0.66 | 0.89 | 0.92 | |||
FLA | 0.77 | 0.72 | 0.84 | |||
PYR | 0.87 | 0.73 | 0.75 | |||
BaA | 0.64 | 0.95 | 0.64 | |||
CHR | 0.68 | 0.92 | 0.68 | |||
BbF | 0.77 | 0.98 | 0.71 | |||
BkF | 0.79 | 0.97 | 0.57 | |||
BaP | 0.89 | 0.86 | ||||
IcdP | 0.82 | 0.88 | ||||
DahA | 0.86 | 0.97 | ||||
BghiP | 0.98 | 0.84 | ||||
Eigenvalues | 12.44 | 1.09 | 13.35 | 1.20 | 10.03 | 3.73 |
Variance (%) | 79.49 | 8.10 | 63.41 | 27.47 | 72.67 | 13.32 |
Pollution source | Traffic emission | Coal combustion | Coal and biomass combustion | Traffic emission | Biomasscom
bustion | Coal combustion |
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Xiao, Y.; Tong, F.; Kuang, Y.; Chen, B. Distribution and Source Apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) in Forest Soils from Urban to Rural Areas in the Pearl River Delta of Southern China. Int. J. Environ. Res. Public Health 2014, 11, 2642-2656. https://doi.org/10.3390/ijerph110302642
Xiao Y, Tong F, Kuang Y, Chen B. Distribution and Source Apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) in Forest Soils from Urban to Rural Areas in the Pearl River Delta of Southern China. International Journal of Environmental Research and Public Health. 2014; 11(3):2642-2656. https://doi.org/10.3390/ijerph110302642
Chicago/Turabian StyleXiao, Yihua, Fuchun Tong, Yuanwen Kuang, and Bufeng Chen. 2014. "Distribution and Source Apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) in Forest Soils from Urban to Rural Areas in the Pearl River Delta of Southern China" International Journal of Environmental Research and Public Health 11, no. 3: 2642-2656. https://doi.org/10.3390/ijerph110302642