[Concentrations and influence factors of polycyclic aromatic hydrocarbons in leaves of dominant species in the Pearl River Delta, South China].

Concentrations of PAHs in leaves of six dominant species in the Pearl River Delta of South China were determined with gas chromatography and mass spectrometry (GC-MS), and synchronously leaf-lipid contents, leaf areas, specific leaf areas (SLA) were measured. The characters of PAHs abundance and influence factors on them were investigated. The results show that concentrations of PAHs in pine needles are higher than those in broad-leaves remarkably, and the highest value (1034.7 ng x g(-1) in Pinus massoniana) is fivefold of the lowest (199.7 ng x g(-1) in Schima superba) . Flu, Phe, Fluo, Pyr, Chr are the main components of sigma PAHs, and the concentrations of 3-ring and 4-ring PAHs exceed 80% of the total PAHs. Significant positive correlations between the components and sigma PAHs were also detected. The PAHs contents by per lipid could reduce inter-species variance obviously, and the diversity is no more than two times (6.8 ng x mg(-1) and 2.7 ng x mg(-1), respectively). Adversely, the PAHs contents by per cm2 magnify inter-species variance, and the highest value (15.3 ng x cm(-2)) ascends to eight times of the lowest (1.9 ng x cm(-2)). Furthermore, significant positive correlation between PAHs and leaf-lipid contents was identified, as well as negative correlation between PAHs and specific leaf areas. All of these indicate that leaf-lipid contents and specific leaf areas are two significant factors which influenced PAHs contents in leaves.