0000000000884013

AUTHOR

Johanna Salmelin

New applications of zoobenthos measurements for risk assessment of chemicals in aquatic ecosystems

Artikkeliväitöskirja. Yhteenveto-osa ja viisi artikkelia. (Artikkelit eivät avoimesti saatavilla.) Article dissertation. An introduction and five articles (not available in this version). Benthic animals in aquatic ecosystems suffer from various anthropogenic pollutants. A challenge in risk assessment of chemicals in aquatic ecosystems (i.e. ecological risk assessment) has been to balance cost-efficiency and effectiveness in detecting early warning signals of chemicals. In this study, hyperspectral imaging and behavioural measurements were evaluated as novel applications for detecting chemical effects on benthic animals, and the reliability of the incidence of chironomid morphological defor…

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Hyperspectral Imaging of Macroinvertebrates : a Pilot Study for Detecting Metal Contamination in Aquatic Ecosystems

The applicability of spectral analysis in detection of freshwater metal contamination was assessed by developing and testing a novel hyperspectral imaging (HSI) application for aquatic insect larvae (Trichoptera: Hydropsychidae). Larvae were first exposed to four different cadmium (Cd) concentrations: 0, 1, 10, and 100 μg L−1 for 96 h. Individual larvae were then preserved in ethanol, inspected with microscopy for the number of anomalies in larval gills, and imaged by hyperspectral camera operating with wavebands between 500 and 850 nm. Three additional larvae from each exposure were analyzed for tissue Cd concentration. Although the larval tissue Cd concentrations correlated positively wit…

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Risk assessment of gypsum amendment on agricultural fields: Effects of sulfate on riverine biota

Gypsum (CaSO4 ∙ 2H2 O) amendment is a promising way of decreasing the phosphorus loading of arable lands, and of thus preventing aquatic eutrophication. However, in freshwaters with low sulfate concentrations, gypsum-released sulfate may pose a threat to the biota. To assess such risks, we performed a series of sulfate toxicity tests in the laboratory and conducted field surveys. These field surveys were associated with a large-scale pilot exercise involving spreading gypsum on agricultural fields covering 18% of the Savijoki River catchment area. The gypsum amendment in such fields resulted in about fourfold increase in the mean sulfate concentration for a 2-month period, and a transient, …

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Blackfly Larvae (Simulium spp.) Can Intensify Methylmercury Biomagnification in Boreal Food Webs

AbstractGlobal pollution of mercury (Hg) threatens ecosystem and human health. We measured total Hg (THg) and monomethylmercury (MMHg) concentrations in filter-feeding blackfly (Simulium spp.) larvae in the inflows and the outflows of six boreal lakes with no Hg point source pollution. THg in the larvae ranged from 0.03 to 0.31 mg kg−1 dw and MMHg between 0.02 and 0.25 mg kg−1 dw. The proportion of MMHg in the larvae was 74 ± 0.16% and ranged from 43 to 98% of THg, the highest proportions being comparable to those typically found in aquatic predatory insects and fish. We compared the larvae MMHg concentrations to river water quality, catchment land-use, and to size-adjusted lake pike THg da…

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Biological responses of midge (Chironomus riparius) and lamprey (Lampetra fluviatilis) larvae in ecotoxicity assessment of PCDD/F-, PCB- and Hg-contaminated river sediments

We evaluated the utility of chironomid and lamprey larval responses in ecotoxicity assessment of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/F)-, polychlorinated biphenyls (PCB)- and mercury (Hg)-contaminated river sediments. Sediment samples were collected from the River Kymijoki with a known industrial pollution gradient. Sediment for the controls and lamprey larvae were obtained from an uncontaminated river nearby. Contamination levels were verified with sediment and tissue PCDD/F, PCB and Hg analyses. Behaviour of sediment-exposed chironomid and lamprey larvae were measured with Multispecies Freshwater Biomonitor© utilizing quadrupole impedance conversion technique. In additi…

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Assessing ecotoxicity of biomining effluents in stream ecosystems by in situ invertebrate bioassays : A case study in Talvivaara, Finland

Mining of sulfide-rich pyritic ores produces acid mine drainage waters and has induced major ecological problems in aquatic ecosystems worldwide. Biomining utilizes microbes to extract metals from the ore, and it has been suggested as a new sustainable way to produce metals. However, little is known of the potential ecotoxicological effects of biomining. In the present study, biomining impacts were assessed using survival and behavioral responses of aquatic macroinvertebrates at in situ exposures in streams. The authors used an impedance conversion technique to measure quantitatively in situ behavioral responses of larvae of the regionally common mayfly, Heptagenia dalecarlica, to discharge…

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Lumbriculus variegatus (Annelida) biological responses and sediment sequential extractions indicate ecotoxicity of lake sediments contaminated by biomining.

Abstract We assessed potential ecotoxicity of lake sediments affected by biomining effluents in northeastern Finland. Growth, reproduction and behavior of the sediment-dwelling oligochaete Lumbriculus variegatus (Muller 1774) were used as ecotoxicity endpoints. Standardized chronic bioassays were used for growth and reproduction, and acute and chronic tests with Multispecies Freshwater Biomonitor (MFB) for behavior assessments. Sequential extractions were used to characterize metal bioavailability and exposure conditions in the sediments, which indicated mining-induced contamination gradients of S, Cu, Ni and U and also bioavailability gradients of S and Ni. Among the ecotoxicity endpoints,…

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