Waste water discharge from a large Ni-Zn open cast mine degrades benthic integrity of Lake Nuasjärvi (Finland)

Visa fullständig post



Permalänk

http://hdl.handle.net/10138/334444

Citation

Luoto , T P , Leppänen , J J & Weckström , J 2019 , ' Waste water discharge from a large Ni-Zn open cast mine degrades benthic integrity of Lake Nuasjärvi (Finland) ' , Environmental Pollution , vol. 255 , no. Part 2 , 113268 . https://doi.org/10.1016/j.envpol.2019.113268

Titel: Waste water discharge from a large Ni-Zn open cast mine degrades benthic integrity of Lake Nuasjärvi (Finland)
Författare: Luoto, Tomi P.; Leppänen, Jaakko Johannes; Weckström, Jan
Upphovmannens organisation: Ecosystems and Environment Research Programme
Helsinki Institute of Sustainability Science (HELSUS)
Environmental Change Research Unit (ECRU)
Datum: 2019-12
Språk: eng
Sidantal: 11
Tillhör serie: Environmental Pollution
ISSN: 0269-7491
DOI: https://doi.org/10.1016/j.envpol.2019.113268
Permanenta länken (URI): http://hdl.handle.net/10138/334444
Abstrakt: The Talvivaara/Terrafame multi-metal mining company is Europe’s largest nickel open cast mine, it is also known for the largest wastewater leakage in the Finnish mining history and a series of other accidents. In this paleolimnological study, influences of a recently constructed treated waste water discharge pipeline into Lake Nuasjärvi were investigated by analyzing past (pre-disturbance) and present community compositions of key aquatic organism groups, including diatoms, Cladocera and Chironomidae, along spatial (distance, water depth) gradients. In addition to defining ecological changes and impacts of saline mine waters in the lake, chironomids were used to quantitatively reconstruct bottom water oxygen conditions before and after the pipe installation (in 2015). The diatom and cladoceran communities, which reflect more the open-water habitat, showed only relatively minor changes throughout the lake, but a general decrease in diversity was observed within both groups. Chironomids, which live on substrates, showed more significant changes, including complete faunal turnovers and deteriorated benthic quality, especially at the sites close to the pipe outlet, where also chironomid diversity was almost completely lost. Furthermore, the reconstructed hypolimnetic oxygen values indicated a major oxygen decline and even anoxia at the sites near the pipe outlet. The limnoecological influence of the pipe decreased at sites located counter-flow or behind underwater barriers suggesting that the waste waters currently have location-specific impacts. Our study clearly demonstrates that whereas the upper water layers appear to have generally maintained their previous state, the deep-water layers close to the pipe outlet have lost their ecological integrity. Furthermore, the current hypolimnetic anoxia close to the pipe indicates enhanced lake stratification caused by the salinated mine waters. This study clearly exhibits the need to investigate different water bodies at several trophic levels in a spatiotemporal context to be able to reliably assess limnoecological impacts of mining.
Subject: 1172 Environmental sciences
Chironomidae
Cladocera
diatoms
mine impact
paleolimnology
MIDGES DIPTERA
Mine impact
INFERENCE MODELS
SUMMER HYPOLIMNETIC OXYGEN
EUTROPHICATION
ECOLOGICAL INTEGRITY
CHIRONOMIDAE
METAL CONTAMINATION
Diatoms
SOUTHERN FINLAND
Paleolimnology
KOLA-PENINSULA
CLIMATE
Referentgranskad: Ja
Licens: cc_by_nc_nd
Användningsbegränsning: openAccess
Parallelpublicerad version: acceptedVersion


Filer under denna titel

Totalt antal nerladdningar: Laddar...

Filer Storlek Format Granska
1_s2.0_S0269749119321529_main.pdf 5.836Mb PDF Granska/Öppna

Detta dokument registreras i samling:

Visa fullständig post