Ecological Risk Assessment of Benzo[a]pyrene in Yellow River Delta

Ecological risk assessment is of great significance to promoting the rational management effectively for the oil-polluted areas. A comprehensive evaluation method of ecological risk, including probabilistic risk assessment and regional ecological risk assessment, is developed through employing the contaminant benzo[a]pyrene as an indicator to assess ecological risk of five oil mining plots, respectively in Yellow River Delta. In this study, firstly we evaluate the ecological risk probability of five oil mining plots using overlapping area of probabilistic curves, and the results show that local ecological risk varies between the maximum 0.4 and the minimum 0.01. Then we overlay boundaries of five administrative divisions in Yellow River Delta and the spatial distribution patterns of ecosystems to generate new risk receptor plaques, and calculate the integrated value of 30 specifically classified plaques for comprehensive evaluation of ecological risk. The results, fluctuating within the range of 0.00005 and 0.25, indicate that local government should be vigilant to ecological risk of benzo[a]pyrene to some extent, although the current situation is not severe in whole.