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Oligochaetes community as an indicator of accelerated eutrophication process in the second oxidation lake Palic [Serbia, Yugoslavia]
1998
Djukic, N. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Maletin, S. | Miljanovic, B. | Tepavcevic, D. | Teodorovic, I.
During the 1981-1996 period, qualitative and quantitative structure of oligachaeta communities as indicator of the eutrophication process was investigated in the lake Palic (the 2nd oxidation lake), Serbia (Yugoslavia). The mean annual number of oligochaetes was related to nutrient concentration (total nitrogen and total phosphorus). The analysed data for both oligochaete community and nutrients, leads to the conclusion that the second oxidation lake Palic can be classified as an highly eutrophic environment, with tendency towards dystrophic, particularly in past two years.
Show more [+] Less [-]Oligochaeta community of "Kapetanski rit" fish pond [Serbia, Yugoslavia]
2001
Mrkic, B. | Dulic, S. (Zavod za zastitu zdravlja, Subotica (Yugoslavia))
During the period May - September 2000, the structure of quality and quantity of Oligochaeta community was investigated on three locations of "Kapetanski rit" fish pond (Serbia, Yugoslavia). At same time were determined some physical and chemical parameters of water temperature, pH value and concentration of dissolved oxygen. In that period of time, the location of Divlje jezero there was no presence of Oligochaeta community. The location of Novo jezero was characterized by 6 species from two families - Naididae and Tubificidae, and the location of Veliko jezero was characterized by only three species. The results from Veliko and Novo jezero show differences in proportional presence and quantity characteristics.
Show more [+] Less [-][Oligochaeta community as indicator of water quality in the Bajski canal [Serbia, Yugoslavia]]
1997
Djukic, N. | Miljanovic, B. | Maletin, S. | Ivanc, A. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za biologiju)
During the period 1977-1996, Oligochaeta have been studied as indicator of water quality in the Bajski canal, Serbia (Yugoslavia). The locality was characterized by the 13 species from nine genera and two families - Naididae and Tubificidae. Species in genera Limnodrilus, Potamothrix and Branchiura were dominant, defining the environment as natural eutrophic.
Show more [+] Less [-]Responses of benthic macroinvertebrate communities to a Bti-based insecticide in artificial microcosm streams Full text
2021
Bordalo, Maria D. | Machado, Ana L. | Campos, Diana | Coelho, Sónia D. | Rodrigues, Andreia C.M. | Lopes, Isabel | Pestana, João L.T.
Bioinsecticides based on the bacterium Bacillus thuringiensis subsp. israelensis (Bti) are increasingly being applied directly into aquatic compartments to control nuisance mosquitoes and blackflies and are generally considered environmentally friendly alternatives to synthetic insecticides. Bti-based insecticides are considered highly selective, being Diptera-specific, and supposedly decompose rapidly in the environment. Nevertheless, their safety to non-target species and freshwater ecosystems has been questioned by recent studies, which in fact document possible indirect effects in aquatic food webs such as the decrease of prey availability to predators. This work aimed to evaluate the potential effects of a Bti-based insecticide (VectoBac® 12AS) on a freshwater macroinvertebrate community and on stream ecological functions by using artificial microcosm streams. Artificial microcosm streams were colonized with a macroinvertebrate community plus periphyton collected in a stream together with Alnus glutinosa leaf packs. They were exposed for 7 days to different Bti treatments (0, 12, 120, 1200 μg/L), which are within the recommended concentrations of application in aquatic compartments for blackfly and mosquito control. Besides invertebrate community structure and abundance, effects were evaluated regarding leaf decomposition and primary production as measures of ecosystem functioning. Community structure was significantly altered in all Bti treatments after 7 days of exposure, mostly due to a decline in chironomids, followed by oligochaetes, which both belong to the deposit-feeders’ functional group. Direct effects on oligochaetes are surprising and require further research. Also, reductions of leaf decomposition due to Bti-induced sublethal effects on shredders (reduced feeding) or mortality of chironomids (that can also feed on coarse organic matter) observed in our study, represent potential indirect effects of Bti in aquatic ecosystems. Our short-exposure experiment evidenced some negative effects on stream benthic invertebrate communities and on ecosystem functioning that must be considered whenever Bti is used in water bodies for blackfly or mosquito control programs.
Show more [+] Less [-]Bioturbation effects on metal release from contaminated sediments are metal-dependent Full text
2019
Xie, Minwei | Simpson, Stuart L. | Wang, Wen-Xiong
Metal flux measurements inform the mobility, potential bioavailability and risk of toxicity for metals in contaminated sediments and therefore is an important approach for sediment quality assessment. The binding and release of metals that contribute to the net flux is strongly influenced by the presence and behaviors of benthic organisms. Here we studied the effects of bioturbation on the mobility and efflux of metals from multi-metal contaminated sediments that inhabited by oligochaete worms or both worms and bivalves. Presence of bivalves enhanced the release of Mn, Co, Ni and Zn but not for copper and chromium, which is likely due to the high affinities of copper and chromium for the solid phase. Metals in the overlying water were primarily associated with fractions smaller than 10 kDa, and the fractionation of all metals were not affected by the presence of the bivalve. Metal fluxes attributed to different processes were also distinguished, and the bioturbation induced effluxes were substantially higher than the diffusive effluxes. Temporal variabilities in the total net effluxes of Mn, Co, Ni and Zn were also observed and were attributed to the biological activities of the bivalves. Overall, the present study demonstrated that the response of different metals to the same bioturbation behavior was different, resulting in distinct mobility and fate of the metal contaminants.
Show more [+] Less [-]1-D and 2-D NMR-based metabolomics of earthworms exposed to endosulfan and endosulfan sulfate in soil Full text
2013
Yuk, Jimmy | Simpson, Myrna J. | Simpson, Andre J.
One-dimensional (1-D) and two-dimensional (2-D) nuclear magnetic resonance (NMR)-based metabolomics was used to investigate the toxic mode of action (MOA) of endosulfan, an organochlorine pesticide, and its degradation product, endosulfan sulfate, to Eisenia fetida earthworms in soil. Three soil concentrations (0.1, 1.0 and 10.0 mg/kg) were used for both endosulfan and endosulfan sulfate. Both earthworm coelomic fluid (CF) and tissues were extracted and then analyzed using 1H and 1H–13C NMR techniques. A similar separation trajectory was observed for endosulfan and endosulfan sulfate-exposed earthworms in the mean principal component analysis (PCA) scores plot for both the earthworm CF and tissue extracts.A neurotoxic and apoptotic MOA was postulated for both endosulfan and endosulfan sulfate exposed earthworms as significant fluctuations in glutamine/GABA–glutamate cycle metabolites and spermidine were detected respectively. This study highlights the application of NMR-based metabolomics to understand molecular-level toxicity of persistent organochlorine pesticides and their degradation products directly in soil.
Show more [+] Less [-]Combined effects of soil moisture and carbaryl to earthworms and plants: Simulation of flood and drought scenarios Full text
2011
Lima, Maria P.R. | Soares, Amadeu M.V.M. | Loureiro, Susana
Combined effects of soil moisture and carbaryl to earthworms and plants: Simulation of flood and drought scenarios Full text
2011
Lima, Maria P.R. | Soares, Amadeu M.V.M. | Loureiro, Susana
Studying tolerance limits in organisms exposed to climatic variations is key to understanding effects on behaviour and physiology. The presence of pollutants may influence these tolerance limits, by altering the toxicity or bioavailability of the chemical. In this work, the plant species Brassica rapa and Triticum aestivum and the earthworm Eisenia andrei were exposed to different levels of soil moisture and carbaryl, as natural and chemical stressors, respectively. Both stress factors were tested individually, as well as in combination. Acute and chronic tests were performed and results were discussed in order to evaluate the responses of organisms to the combination of stressors. When possible, data was fitted to widely employed models for describing chemical mixture responses. Synergistic interactions were observed in earthworms exposed to carbaryl and drought conditions, while antagonistic interactions were more representative for plants, especially in relation to biomass loss under flood-simulation conditions.
Show more [+] Less [-]Combined effects of soil moisture and carbaryl to earthworms and plants: simulation of flood and drought scenarios Full text
1000 | 2011
Lima, Maria P. R. | Soares, Amadeu M. V. M. | Loureiro, Susana
Studying tolerance limits in organisms exposed to climatic variations is key to understanding effects on behaviour and physiology. The presence of pollutants may influence these tolerance limits, by altering the toxicity or bioavailability of the chemical. In this work, the plant species Brassica rapa and Triticum aestivum and the earthworm Eisenia andrei were exposed to different levels of soil moisture and carbaryl, as natural and chemical stressors, respectively. Both stress factors were tested individually, as well as in combination. Acute and chronic tests were performed and results were discussed in order to evaluate the responses of organisms to the combination of stressors. When possible, data was fitted to widely employed models for describing chemical mixture responses. Synergistic interactions were observed in earthworms exposed to carbaryl and drought conditions, while antagonistic interactions were more representative for plants, especially in relation to biomass loss under flood-simulation conditions. (C) 2011 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Effects of biochar and the earthworm Eisenia fetida on the bioavailability of polycyclic aromatic hydrocarbons and potentially toxic elements Full text
2011
Gomez-Eyles, Jose L. | Sizmur, Tom | Collins, Chris D. | Hodson, Mark E.
Effects of biochar and the earthworm Eisenia fetida on the bioavailability of polycyclic aromatic hydrocarbons and potentially toxic elements Full text
2011
Gomez-Eyles, Jose L. | Sizmur, Tom | Collins, Chris D. | Hodson, Mark E.
Polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) were monitored over 56 days in calcareous contaminated-soil amended with either or both biochar and Eisenia fetida. Biochar reduced total (449 to 306mgkg⁻¹) and bioavailable (cyclodextrin extractable) (276 to 182mgkg⁻¹) PAHs, PAH concentrations in E. fetida (up to 45%) but also earthworm weight. Earthworms increased PAH bioavailability by >40%. Combined treatment results were similar to the biochar-only treatment. Earthworms increased water soluble Co (3.4 to 29.2mgkg⁻¹), Cu (60.0 to 120.1mgkg⁻¹) and Ni (31.7 to 83.0mgkg⁻¹) but not As, Cd, Pb or Zn; biochar reduced water soluble Cu (60 to 37mgkg⁻¹). Combined treatment results were similar to the biochar-only treatment but gave a greater reduction in As and Cd mobility. Biochar has contaminated land remediation potential, but its long-term impact on contaminants and soil biota needs to be assessed.
Show more [+] Less [-]Effects of biochar and the earthworm Eisenia fetida on the bioavailability of polycyclic aromatic hydrocarbons and potentially toxic elements Full text
2011
Gomez-Eyles, Jose L. | Sizmur, Tom | Collins, Christopher David | Hodson, Mark Edward
Polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) were monitored over 56 days in calcareous contaminated-soil amended with either or both biochar and Eisenia fetida. Biochar reduced total (449 to 306mgkg(-1)) and bioavailable (cyclodextrin extractable) (276 to 182mgkg(-1)) PAHs, PAH concentrations in E. fetida (up to 45%) but also earthworm weight. Earthworms increased PAH bioavailability by >40%. Combined treatment results were similar to the biochar-only treatment. Earthworms increased water soluble Co (3.4 to 29.2mgkg(-1)), Cu (60.0 to 120.1mgkg(-1)) and Ni (31.7 to 83.0mgkg(-1)) but not As, Cd, Pb or Zn; biochar reduced water soluble Cu (60 to 37mgkg(-1)). Combined treatment results were similar to the biochar-only treatment but gave a greater reduction in As and Cd mobility. Biochar has contaminated land remediation potential, but its long-term impact on contaminants and soil biota needs to be assessed.
Show more [+] Less [-]The effects of the insecticide lambda-Cyhalothrin on the earthworm Eisenia fetida under experimental conditions of tropical and temperate regions Full text
2011
García, Marcos | Scheffczyk, Adam | Garcia, Terezinha | Römbke, Jörg
Plant Protection Products can affect soil organisms and thus might have negative impacts on soil functions. Little research has been performed on their impact on tropical soils. Therefore, the effects of the insecticide lambda-Cyhalothrin on earthworms were evaluated in acute and chronic laboratory tests modified for tropical conditions, i.e. at selected temperatures (20 and 28°C) and with two strains (temperate and tropical) of the compost worm Eisenia fetida. The insecticide was spiked in two natural soils, in OECD artificial soil and a newly developed tropical artificial soil. The effects of lambda-Cyhalothrin did rarely vary in the same soil at tropical (LC50: 68.5–229mg a.i./kg dry weight (DW); EC50: 54.2–60.2mg a.i./kg DW) and temperate (LC50: 99.8–140mg a.i./kg DW; EC50: 37.4–44.5mg a.i./kg DW) temperatures. In tests with tropical soils and high temperature, effect values differed by up to a factor of ten.
Show more [+] Less [-]Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action Full text
2011
McKelvie, Jennifer R. | Wolfe, David M. | Celejewski, Magda A. | Alaee, M. (Mehran) | Simpson, Andre J. | Simpson, Myrna J.
Nuclear magnetic resonance (NMR) – based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms.
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