title: [Environmental factors on distribution of polycyclic aromatic hydrocarbons in soils from Dashiwei karst giant doline (Tiankeng) in Guangxi, China].
abstract: With typical Dashiwei karst great doline (Tiankeng) located in Leye county, Guangxi in China as study area, the soil samples of different karst topography were collected and analyzed utilizing GC-MS for the 16 PAHs. Environmental factors were observed by weather instrument. The results showed that the total PAHs concentration in soils of the ground (the positive landform) of Dashiwei great doline ranged from 75.20 ng x g(-1) to 373.79 ng x g(-1), with an average of 120.70 ng x g(-1). In Dashwei great doline (the negative landform), the total PAHs concentration in soils of cliff ranged from 19.88 ng x g(-1) to 330.79 ng x g(-1), with an average of 131.86 ng x g(-1); the concentration of the bottom section ranged from 127.48 ng x g(-1) to 661.62 ng x g(-1), with an average of 395.22 ng x g(-1); and the concentration of the underground river ranged from 1132.11 ng x g(-1) to 1 749.95 ng x g(-1), with an average of 1412.39 ng x g(-1). The PAHs compounds were mainly 4-6 rings PAH. The primary sources of PAHs were pyrogenic sources. The pollution approaches were mainly atmospheric transportation and deposition. As a whole, the spatial distribution of PAHs in soils in Dashiwei doline gradually increased from the surface-the cliff-the bottom-the underground river with the increase of temperature and relative humidity. Accumulation and differentiation of PAHs in a vertical way were showed by "coal trap effect". Environmental factors influencing the distribution of PAHs in soils were majorly temperature, followed by humidity, wind direction and wind speed, and in some parts multi environmental factors worked together. The effect of the environmental factors was bigger in summer than in winter. Monitoring of PAHs discovered that the total PAHs concentration in soils of the bottom was 3.5 times higher in 2007 than in 2006. As a consequence, this study suggested that the accumulation and differentiation of karst doline was related with these important environmental factors.
authors: Institute of Karst Geology, Chinese Academy of Geological Science, Guilin 541004, China. karstkxs@126.com
authors: Xiang-Sheng
authors: XS
authors: Kong
authors: Shi-Hua
authors: SH
authors: Qi
authors: Zhong-Cheng
authors: ZC
authors: Jiang
authors: Bao-Jian
authors: BJ
authors: Huang
mesh_terms: D002681:China; D004777:Environment; D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D006813:Humidity; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D012621:Seasons; D012989:Soil Pollutants / Q000032:analysis*; D013696:Temperature
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants