Elevated Mercury Deposition, Accumulation, and Migration in a Karst Forest

The karst forest is one of the extremely sensitive and fragile ecosystems in southwest China, where the biogeochemical cycling of mercury (Hg) is largely unknown. In this study, we investigated the litterfall deposition, accumulation, and soil migration of Hg in an evergreen-deciduous broadleaf karst forest using high-resolution sampling and stable isotope techniques. Results show that elevated litterfall Hg concentrations and fluxes in spring are due to the longer lifespan of evergreen tree foliage exposed to atmospheric Hg0. The hillslope has 1-2 times higher litterfall Hg concentration compared to the low-lying land due to the elevated atmospheric Hg levels induced by topographical and physiological factors. The Hg isotopic model suggests that litterfall Hg depositions account for ∼80% of the Hg source contribution in surface soil. The spatial trend of litterfall Hg deposition cannot solely explain the trend of Hg accumulation in the surface soil. Indeed, soil erosion enhances Hg accumulation in soil of low-lying land, with soil Hg concentration up to 5-times greater than the concentration on the hillslope. The high level of soil Hg migration in the karst forest poses significant ecological risks to groundwater and downstream aquatic ecosystems.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:57

Enthalten in:

Environmental science & technology - 57(2023), 45 vom: 14. Nov., Seite 17490-17500

Sprache:

Englisch

Beteiligte Personen:

Du, Hu [VerfasserIn]
Wang, Xun [VerfasserIn]
Yuan, Wei [VerfasserIn]
Wu, Fei [VerfasserIn]
Jia, Longyu [VerfasserIn]
Liu, Nantao [VerfasserIn]
Lin, Che-Jen [VerfasserIn]
Gan, Jiang [VerfasserIn]
Zeng, Fuping [VerfasserIn]
Wang, Kelin [VerfasserIn]
Feng, Xinbin [VerfasserIn]

Links:

Volltext

Themen:

FXS1BY2PGL
Journal Article
Karst forest
Mercury
Mercury accumulation
Mercury deposition
Mercury migration
Research Support, Non-U.S. Gov't
Soil
Soil Pollutants

Anmerkungen:

Date Completed 15.11.2023

Date Revised 15.11.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1021/acs.est.3c05409

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM363999744