Atlas of Contaminated Sites

Notable case, Lanping (Nujiang), Yunnan, China

Lanping lead-zinc mine

兰坪铅锌矿

China's largest lead-zinc mine, an open pit in a high-altitude valley of north-western Yunnan. Lead, zinc and cadmium have contaminated the valley's soils and the maize fields downstream; the pioneer plants on its tailings have long been studied for phytostabilisation.

Phytoremediation

Status
Remediation under way
Media
soil, living organisms
Kind of site
mining
  1. Area. The extent of contaminated soil in the mining valley is not quantified in the sources read. The coordinates are those of Lanping County (Wikidata), not of the mine.

Contaminants

Metals

Status

Remediation under way

There is a reclamation area on the mine, studied in 2025 (Huang and colleagues), and between 2017 and 2019 the contaminated maize fields were treated with immobilising agents (Wang and colleagues 2021). Cadmium in the mine's soil remains between 95.6 and 388.7 times the Yunnan background value. No official overview of the works was found.

Story

The Lanping mine is described as China's largest lead-zinc mine and the largest open-pit working of these metals in Asia. A 2019 study of the mining valley compared the upstream, mining and downstream zones: in the mining area lead and zinc were 56 and 47 times the world soil average; downstream, lead, zinc and cadmium were 8, 8 and 18 times; upstream 6, 7 and 6 times, a sign of an already high geochemical background. The authors accordingly propose local baseline values of 169.93 mg/kg for lead, 569.06 for zinc and 4.13 for cadmium (Li and colleagues 2019).

The tailings are colonised by pioneer herbs. A survey of the abandoned workings found 18 dominant species, all herbaceous, with metal contents above normal: three of them exceeded 60 mg/kg of cadmium in their shoots (Zhang and colleagues 2020).

In the maize fields contaminated with cadmium and lead, immobilisation was chosen: raising soil pH from 5.24 to 6.24 cut extractable cadmium and lead by 47.8% and 74.7%, and between 2017 and 2019 the share of grain samples within the limits rose from 77.4% to 96.2% for cadmium and from 90.6% to 96.2% for lead (Wang and colleagues 2021).

Timeline

  1. 2008Publication of the study on pioneer plants of the tailings for phytostabilisation.
  2. 2017Start of the three-year assessment of metal immobilisation in the maize fields.
  3. 2019Geochemical baseline values defined for the soils of the mining valley.
  4. 2025Study of nitrogen-cycle bacteria in the mine's reclamation area.

Remediation

  1. 2017soil amendmentImmobilisation of cadmium and lead in maize fields by raising pH (2017–2019).

Plants and fungi at this site

PhytoremediationField scale

Artemisia roxburghiana, Potentilla saundersiana, Oxyria sinensis, Coriaria sinica, Miscanthus nepalensis

A field survey, not a plot trial: ten pioneer plants growing spontaneously on the lead-zinc tailings, in the early phase of phytostabilisation. Metals and fertility were compared in rhizosphere soil and bare substrate, as were metals in roots and shoots. Five of the ten species are listed here.

Outcome In the rhizosphere of Artemisia roxburghiana lead, zinc and copper were 56.23%, 83.00% and 84.36% lower than in bare substrate. Under Potentilla saundersiana available nitrogen, phosphorus and potassium and organic matter rose by 241.83%, 170.76%, 49.09% and 81.60%. Metals taken up stayed mainly in the roots, with little transfer to the shoots: plants suited to stabilising, not extracting (Lei and Duan 2008).

PhytoremediationField scale

Picris hieracioides, Carum bretschneideri, Corydalis yanhusuo, Euphorbia fischeriana, Cynoglossum amabile

Survey of the 18 dominant species (13 families, all herbaceous) on the abandoned workings, with bioconcentration and translocation factors for six metals, to choose species for use in restoration.

Outcome Corydalis yanhusuo, Carum bretschneideri and Picris hieracioides had 62.29, 76.49 and 85.09 mg/kg of cadmium in their shoots, with bioconcentration factors of 0.57, 0.58 and 0.66 and translocation factors of 0.89, 0.45 and 1.48: candidates for cadmium extraction, though with bioconcentration factors below 1. Euphorbia fischeriana and Cynoglossum amabile accumulated very little (0.46 and 0.23 mg/kg) and are suggested as cover plants (Zhang and colleagues 2020).

From the literature

Species that acted on one of this site's contaminants in at least one study. The list is automatic and takes no account of this site's soil, concentrations or climate.

Plants

Fungi

The rest are on the contaminant pages.

Sources

  1. Li Z., Deblon J., Zu Y., Colinet G., Li B., He Y. Geochemical Baseline Values Determination and Evaluation of Heavy Metal Contamination in Soils of Lanping Mining Valley (Yunnan Province, China). IJERPH 16(23): 4686 (abstract), MDPI, 2019
  2. Lei D., Duan C. Restoration potential of pioneer plants growing on lead-zinc mine tailings in Lanping, southwest China (abstract), Journal of Environmental Sciences, 2008
  3. Zhang L. et al. Potential of Accumulation and Application of Dominant Plants in Lanping Lead-zinc Mine, Yunnan Province (abstract), Huanjing Kexue, 2020
  4. Wang W. et al. Soil Metal Immobilization in Agricultural Land Contaminated with Cadmium and Lead: A Case Study of Effectiveness Evaluation in Lanping, Southwest China. Bulletin of Environmental Contamination and Toxicology (abstract), Springer, 2021
  5. Huang Z.K. et al. Characteristics of Nitrogen Cycle-related Bacterial Community and Its Response to Soil in the Main Lead-zinc Mine Reclamation Area of Lanping. Huanjing Kexue (abstract), Huanjing Kexue, 2025
  6. Lanping Bai and Pumi Autonomous County (Q1152620), coordinates, Wikidata, 2026

Draft compiled from public sources, not yet reviewed.