Welcome to Chinese Journal of Ecology! Today is Share:

Chinese Journal of Ecology ›› 2025, Vol. 44 ›› Issue (5): 1551-1560.doi: 10.13292/j.1000-4890.202505.032

Previous Articles     Next Articles

Characteristics of mercury fraction of forest soil along an urbanization gradient in Shanghai.

LI Ran1, WANG Yanlin2, WANG Yongjie3, DENG Hong1,4,5*   

  1. (1College of Ecology and Environmental Science, East China Normal University, Shanghai 200241, China; 2Qiwen Middle School, Linping District, Hangzhou 311199, China; 3School of Geographical Sciences, East China Normal University, Shanghai 200241, China; 4Shanghai Key Laboratory of Urbanization Ecological Processes and Ecological Restoration, East China Normal University, Shanghai 200241, China; 5Institute of Eco-Chongming, Shanghai 202162, China).

  • Online:2025-06-10 Published:2025-05-13

PDF (PC)

6

Abstract:

Urbanization and plant community play important roles in mercury migration and transformation in soils. To investigate the characteristics of mercury along an urbanization gradient, we analyzed the total mercury (THg), methylmercury (MeHg), and total organic carbon (TOC) concentrations in the soil of three forests, i.e. Cinnamomum camphora forest, Metasequoia glyptostroboides forest and evergreen-deciduous mixed forest, from the outer suburb, inner suburb and central urban district of Shanghai. The speciation of soil mercury was analyzed by thermal analysis method. The results showed that: (1) the THg concentration in the surface soil (0-2 cm) of urban forests varied from 34.01 to 317.98 ng·g-1, with an obvious spatial pattern of central urban district > inner suburb > outer suburb, indicating that soil mercury was affected by urbanization. Based on the annual data, MeHg concentration of surface soil was correlated with THg concentration (R2=0.323, P<0.01) instead of soil TOC concentration (P>0.05). (2) Across the 0-20 cm soil profile, soil MeHg concentration was significantly positively correlated with both THg and TOC concentrations (R2THg=0.231, R2TOC=0.588, P<0.01). Hg forms affected the formation of mercury methylization. The speciations of adsorbed and organically bound mercury were important factors influencing the methylation of mercury in soil. (3) Compared to Cinnamomum camphora forest, soil MeHg concentration was higher in Metasequoia glyptostroboides forest and mixed forest, indicating that soils under deciduous trees were more methylated.

Key words: urbanization, urban forest soil, total mercury, methylmercury, mercury with different thermal stability