High mercury accumulation in two subtropical evergreen forests in South China and potential determinants.
J Environ Manage
; 183(Pt 3): 488-496, 2016 Dec 01.
Article
em En
| MEDLINE
| ID: mdl-27623371
ABSTRACT
Forests play an important role in global mercury (Hg) cycling. To explain the high Hg accumulation in subtropical forest ecosystems, we studied temporal dynamics of Hg, carbon (C), nitrogen (N), and sulfur (S) in forest soil profiles, as well as litterfall flux and precipitation, in an old-growth moist evergreen broadleaf (EB) forest and a mossy coppice (MC) forest from South China over seven years. The mean soil Hg concentration was 257 ± 14 ng g-1 in the O-horizon and 248 ± 15 ng g-1 in the A-horizon for the EB forest, and 94 ± 27 ng g-1 in the O-horizon and 70 ± 11 ng g-1 in the A-horizon for the MC forest. Annual variations in Hg concentration were suggested to be associated with variations in precipitation and litterfall biomass. Significant vertical Hg transport was only observed in the MC forest, which was attributed to its lower organic matter content. Correlation and stoichiometry analyses further suggested that the dynamics in Hg concentration in the forest floor was also closely linked to the variation in S concentration. Additionally, the difference in the soil Hg pool between these two forests was attributed to different litterfall biomass fluxes.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Poluentes do Solo
/
Florestas
/
Monitoramento Ambiental
/
Mercúrio
País/Região como assunto:
Asia
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
China