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  • 1.
    Amid, C.
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Olstedt, M.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Le Lan, H.
    Tran Thi Minh, H.
    Van den Brink, P. J.
    Hellström, M.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Tedengren, Michael
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Additive effects of the herbicide glyphosate and elevated temperature on the branched coral Acropora formosa in Nha Trang, Vietnam2018In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 25, no 14, p. 13360-13372Article in journal (Refereed)
    Abstract [en]

    The combined effects of the herbicide glyphosate and elevated temperature were studied on the tropical staghorn coral Acropora formosa, in Nha Trang bay, Vietnam. The corals were collected from two different reefs, one close to a polluted fish farm and one in a marine-protected area (MPA). In the laboratory, branches of the corals were exposed to the herbicide glyphosate at ambient (28 degrees C) and at 3 degrees C elevated water temperatures (31 degrees C). Effects of herbicide and elevated temperature were studied on coral bleaching using photography and digital image analysis (new colorimetric method developed here based on grayscale), chlorophyll a analysis, and symbiotic dinoflagellate (Symbiodinium, referred to as zooxanthellae) counts. All corals from the MPA started to bleach in the laboratory before they were exposed to the treatments, indicating that they were very sensitive, as opposed to the corals collected from the more polluted site, which were more tolerant and showed no bleaching response to temperature increase or herbicide alone. However, the combined exposure to the stressors resulted in significant loss of color, proportional to loss in chlorophyll a and zooxanthellae. The difference in sensitivity of the corals collected from the polluted site versus the MPA site could be explained by different symbiont types: the resilient type C3u and the stress-sensitive types C21 and C23, respectively. The additive effect of elevated temperatures and herbicides adds further weight to the notion that the bleaching of coral reefs is accelerated in the presence of multiple stressors. These results suggest that the corals in Nha Trang bay have adapted to the ongoing pollution to become more tolerant to anthropogenic stressors, and that multiple stressors hamper this resilience. The loss of color and decrease of chlorophyll a suggest that bleaching is related to concentration of chloro-pigments. The colorimetric method could be further fine-tuned and used as a precise, non-intrusive tool for monitoring coral bleaching in situ.

  • 2. Arias-Andrés, M.
    et al.
    Rämö, Robert
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Torres, F. Mena
    Ugalde, R.
    Grandas, L.
    Ruepert, C.
    Castillo, L. E.
    Van den Brink, P. J.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Lower tier toxicity risk assessment of agriculture pesticides detected on the Rio Madre de Dios watershed, Costa Rica2018In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 25, no 14, p. 13312-13321Article in journal (Refereed)
    Abstract [en]

    Costa Rica is a tropical country with one of the highest biodiversity on Earth. It also has an intensive agriculture, and pesticide runoff from banana and pineapple plantations may cause a high toxicity risk to non-target species in rivers downstream the plantations. We performed a first tier risk assessment of the maximum measured concentrations of 32 pesticides detected over 4 years in the River Madre de Dios (RMD) and its coastal lagoon on the Caribbean coast of Costa Rica. Species sensitivity distributions (SSDs) were plotted in order to derive HC5 values for each pesticide, i.e., hazard concentrations for 5 % of the species, often used as environmental criteria values in other countries. We also carried out toxicity tests for selected pesticides with native Costa Rican species in order to calculate risk coefficients according to national guidelines in Costa Rica. The concentrations of herbicides diuron and ametryn and insecticides carbofuran, diazinon, and ethoprophos exceeded either the HC5 value or the lower limit of its 90 % confidence interval suggesting toxic risks above accepted levels. Risk coefficients of diuron and carbofuran derived using local guidelines indicate toxicity risks as well. The assessed fungicides did not present acute toxic risks according to our analysis. Overall, these results show a possible toxicity of detected pesticides to aquatic organisms and provide a comparison of Costa Rican national guidelines with more refined methods for risk assessment based on SSDs. Further higher tier risk assessments of pesticides in this watershed are also necessary in order to consider pesticide water concentrations over time, toxicity from pesticide mixtures, and eventual effects on ecosystem functions.

  • 3.
    Bonaglia, Stefano
    et al.
    Stockholm University, Faculty of Science, Department of Geological Sciences.
    Bartoli, Marco
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Rahm, Lars
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Svensson, Ola
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Shakeri Yekta, Sepehr
    Brüchert, Volker
    Stockholm University, Faculty of Science, Department of Geological Sciences.
    Effect of reoxygenation and Marenzelleria spp. bioturbation on Baltic Sea sediment metabolism2013In: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 482, p. 43-55Article in journal (Refereed)
    Abstract [en]

    Nutrient reduction and the improvement of bottom water oxygen concentrations are thought to be key factors in the recovery of eutrophic aquatic ecosystems. The effects of reoxygenation and bioturbation of natural hypoxic sediments in the Baltic Sea were studied using a mesocosm experiment. Anoxic sediment box cores were collected from 100 m depth in Kanholmsfjärden (Stockholm Archipelago) and maintained in flow-through mesocosms with 3 treatments: (1) hypoxic: supplied with hypoxic water; (2) normoxic: supplied with oxic water; and (3) Marenzelleria: supplied with oxic water and the polychaete Marenzelleria spp. (2000 ind. m–2). After a 7 wk long conditioning period, net fluxes of dissolved O2, CH4, Fe2+, Mn2+, NH4+, NO2-, NO3-, PO43- and H4SiO4, and rates of nitrate ammonification (DNRA), denitrification and anammox were determined. Phosphate was taken up by the sediment in all treatments, and the uptake was highest in the normoxic treatment with Marenzelleria. Normoxic conditions stimulated the denitrification rate by a factor of 5. Denitrification efficiency was highest under normoxia (50%), intermediate in bioturbated sediments (16%), and very low in hypoxic sediments (4%). The shift from hypoxic to normoxic conditions resulted in a significantly higher retention of NH4+, H4SiO4 and Mn2+ in the sediment, but the bioturbation by Marenzelleria reversed this effect. Results from our study suggest that bioturbation by Marenzelleria stimulates the exchange of solutes between sediment and bottom water through irrigation and enhances bacterial sulfate reduction in the burrow walls. The latter may have a toxic effect on nitrifying bacteria, which, in turn, suppresses denitrification rates.

  • 4.
    Bonaglia, Stefano
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. University of Southern Denmark, Denmark.
    Broman, Elias
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, Stockholm University Baltic Sea Centre.
    Brindefalk, Björn
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Hedlund, Erika
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Hjorth, Tomas
    Rolff, Carl
    Stockholm University, Faculty of Science, Stockholm University Baltic Sea Centre.
    Nascimento, Francisco J. A.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, Stockholm University Baltic Sea Centre.
    Udekwu, Klas
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Activated carbon stimulates microbial diversity and PAH biodegradation under anaerobic conditions in oil-polluted sediments2020In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 248, article id 126023Article in journal (Refereed)
    Abstract [en]

    Biodegradation by microorganisms is a useful tool that helps alleviating hydrocarbon pollution in nature. Microbes are more efficient in degradation under aerobic than anaerobic conditions, but the majority of sediment by volume is generally anoxic. Incubation experiments were conducted to study the biodegradation potential of naphthalene-a common polycyclic aromatic hydrocarbon (PAH)-and the diversity of microbial communities in presence/absence of activated carbon (AC) under aerobic/anaerobic conditions. Radio-respirometry experiments with endogenous microorganisms indicated that degradation of naphthalene was strongly stimulated (96%) by the AC addition under anaerobic conditions. In aerobic conditions, however, AC had no effects on naphthalene biodegradation. Bioaugmentation tests with cultured microbial populations grown on naphthalene showed that AC further stimulated (92%) naphthalene degradation in anoxia. Analysis of the 16S rRNA gene sequences implied that sediment amendment with AC increased microbial community diversity and changed community structure. Moreover, the relative abundance of Geobacter, Thiobacillus, Sulfuricurvum, and methanogenic archaea increased sharply after amendment with AC under anaerobic conditions. These results may be explained by the fact that AC particles promoted direct interspecies electron transfer (DIET) between microorganisms involved in PAH degradation pathways. We suggest that important ecosystem functions mediated by microbes-such as hydrocarbon degradation-can be induced and that AC enrichment strategies can be exploited for facilitating bioremediation of anoxic oil-contaminated sediments and soils.

  • 5.
    Bonaglia, Stefano
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Rämö, Robert
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Marzocchi, Ugo
    Le Bouille, Léonie
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Leermakers, Martine
    Nascimento, Francisco J. A.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Capping with activated carbon reduces nutrient fluxes, denitrification and meiofauna in contaminated sediments2019In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 148, p. 515-525Article in journal (Refereed)
    Abstract [en]

    Sediment capping with activated carbon (AC) is an effective technique used in remediation of contaminated sediments, but the ecological effects on benthic microbial activity and meiofauna communities have been largely neglected. This study presents results from a 4-week experiment investigating the influence of two powdered AC materials (bituminous coal-based and coconut shell-derived) and one control material (clay) on biogeochemical processes and meiofauna in contaminated sediments. Capping with AC induced a 62‒63% decrease in denitrification and a 66‒87 % decrease in dissimilatory nitrate reduction to ammonium (DNRA). Sediment porewater pH increased from 7.1 to 9.0 and 9.7 after addition of bituminous AC and biomass-derived AC, respectively. High pH (>8) persisted for at least two weeks in the bituminous AC and for at least 24 days in the coconut based AC, while capping with clay had no effect on pH. We observed a strong impact (nitrate fluxes being halved in presence of AC) on nitrification activity as nitrifiers are sensitive to high pH. This partly explains the significant decrease in nitrate reduction rates since denitrification was almost entirely coupled to nitrification. Total benthic metabolism estimated by sediment oxygen uptake was reduced by 30 and 43 % in presence of bituminous coal-based AC and coconut shell-derived AC, respectively. Meiofauna abundances decreased by 60‒62 % in the AC treatments. Taken together, these observations suggest that AC amendments deplete natural organic carbon, intended as food, to heterotrophic benthic communities. Phosphate efflux was 91 % lower in presence of bituminous AC compared to untreated sediment probably due to its content of aluminum (Al) oxides, which have high affinity for phosphate. This study demonstrates that capping with powdered AC produces significant effects on benthic biogeochemical fluxes, microbial processes and meiofauna abundances, which are likely due to an increase in porewater pH and to the sequestration of natural, sedimentary organic matter by AC particles.

  • 6.
    Broman, Elias
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, Stockholm University Baltic Sea Centre.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Sommer, Christian
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Creer, Simon
    Nascimento, Francisco J. A.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, Stockholm University Baltic Sea Centre.
    Salinity drives meiofaunal community structure dynamics across the Baltic ecosystem2019In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 28, no 16, p. 3813-3829Article in journal (Refereed)
    Abstract [en]

    Coastal benthic biodiversity is under increased pressure from climate change, eutrophication, hypoxia, and changes in salinity due to increase in river runoff. The Baltic Sea is a large brackish system characterized by steep environmental gradients that experiences all of the mentioned stressors. As such it provides an ideal model system for studying the impact of on‐going and future climate change on biodiversity and function of benthic ecosystems. Meiofauna (animals < 1 mm) are abundant in sediment and are still largely unexplored even though they are known to regulate organic matter degradation and nutrient cycling. In this study, benthic meiofaunal community structure was analysed along a salinity gradient in the Baltic Sea proper using high‐throughput sequencing. Our results demonstrate that areas with higher salinity have a higher biodiversity, and salinity is probably the main driver influencing meiofauna diversity and community composition. Furthermore, in the more diverse and saline environments a larger amount of nematode genera classified as predators prevailed, and meiofauna‐macrofauna associations were more prominent. These findings show that in the Baltic Sea, a decrease in salinity resulting from accelerated climate change will probably lead to decreased benthic biodiversity, and cause profound changes in benthic communities, with potential consequences for ecosystem stability, functions and services.

  • 7.
    Cornelissen, Gerard
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Amstaetter, Katja
    Hauge, Audun
    Schaanning, Morten
    Beylich, Bjornar
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Breedveld, Gijs D.
    Oen, Amy M. P.
    Eek, Espen
    Large-Scale Field Study on Thin-Layer Capping of Marine PCDD/F-Contaminated Sediments in Grenlandfjords, Norway: Physicochemical Effects2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 21, p. 12030-12037Article in journal (Refereed)
    Abstract [en]

    A large-scale field experiment on in situ thin-layer capping was carried out in the polychlorinated dibenzodioxin, and dibenzofuran (PCDD/F) contaminated Grenlandsfjords, Norway The main focus of the,trial Was to,test the effectiveness of active caps (targeted thickness of 2.5 cm) consisting of powdered activated carbon (AC) mixed into locally dredged clean clay. Nonactive caps (targed thickness of 5 cm) consisting of clay without, AC as well as crushed limestone were also tested Fields with areas of 10 000 to 40 000 m(2) were established at 30 to 100 m water depth. Auxiliary shaken laboratory batch experiments showed that 2% of the applied powdered AC substantially reduced PCDD/F porewater concentrations, by >90% for tetra-, penta- and hexa-clorinated congeners to 60-70% for octachlorinated ones. In situ AC profiles revealed that the AC was mixed into the sediment to 3 to 5 cm depth in 20 months. Only around 25% of the AC was found inside the pilot fields. Sediment-to-water PCDD/F fluxes measured by in situ diffusion chambers were significantly lower at the capped fields than at reference fields in the same fjord, reductions being largest for the limestone (50-90%) followed by clay (50-70%), and the AC + clay (60%). Also reductions in overlying aqueous PCDD/F concentrations measured by passive samplers were significant in most cases (20-40% reduction), probably because of the large size of the trial fields. The AC was less effective in the field than in the laboratory, probably due to prolonged sediment-to-AC mass transfer times for PCDD/Fs and field factors such as integrity of the cap, new deposition Of contaminated sediment particles, and bioturbation. The present field data indicate that slightly thicker layers of limestone and dredged clay can show as good physicochemical effectiveness as thin caps of AC mixed with clay, at least for PCDD/Fs during the first two years after cap placement.

  • 8.
    Cornelissen, Gerard
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Krusa, Marie Elmquist
    Breedveld, Gijs D.
    Eek, Espen
    Oen, Amy M. P.
    Arp, Hans Peter H.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Samuelsson, Göran
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Hedman, Jenny E.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Stokland, Oystein
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Remediation of Contaminated Marine Sediment Using Thin-Layer Capping with Activated Carbon-A Field Experiment in Trondheim Harbor, Norway2011In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 45, no 14, p. 6110-6116Article in journal (Refereed)
    Abstract [en]

    In situ amendment of contaminated sediments using activated carbon (AC) is a recent remediation technique, where the strong sorption of contaminants to added AC reduces their release from sediments and uptake into organisms. The current study describes a marine underwater field pilot study in Trondheim harbor, Norway, in which powdered AC alone or in combination with sand or clay was tested as a thin-layer capping material for polycyclic aromatic hydrocarbon (PAH)-contaminated sediment. Several novel elements were included, such as measuring PAH fluxes, no active mixing of AC into the sediment, and the testing of new manners of placing a thin AC cap on sediment, such as AC+clay and AC+sand combinations. Innovative chemical and biological monitoring methods were deployed to test capping effectiveness. In situ sediment-to-water PAH fluxes were measured using recently developed benthic flux chambers. Compared to the reference field, AC capping reduced fluxes by a factor of 2-10. Pore water PAH concentration profiles were measured in situ using anew passive sampler technique, and yielded a reduction factor of 2-3 compared to the reference field. The benthic macrofauna composition and biodiversity were affected by the AC amendments, AC + clay having a lower impact on the benthic taxa than AC-only or AC + sand. In addition, AC + clay gave the highest AC recoveries (60% vs 30% for AC-only and AC + sand) and strongest reductions in sediment-to-water PAH fluxes and porewater concentrations. Thus, application of an AC-clay mixture is recommended as the optimal choice of the currently tested thin-layer capping methods for PAHs, and more research on optimizing its implementation is needed.

  • 9.
    Cornelissen, Gerard
    et al.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry. Norwegian Geotechnical Institute, Norway; Norwegian University of Life Sciences (NMBU), Norway.
    Schaanning, Morten
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Eek, Espen
    A large-scale field trial of thin-layer capping of PCDD/F-contaminated sediments: Sediment-to-water fluxes up to 5 years post-amendment2016In: Integrated Environmental Assessment and Management, ISSN 1551-3777, E-ISSN 1551-3793, Vol. 12, no 2, p. 216-221Article in journal (Refereed)
    Abstract [en]

    The longer-term effect (3-5 y) of thin-layer capping on in situ sediment-to-surface water fluxes was monitored in a large-scale field experiment in the polychlorinated dibenzodioxin and dibenzofuran (PCDD/F) contaminated Grenlandfjords, Norway (4 trial plots of 10000 to 40000 m(2) at 30 to 100 m water depth). Active caps (designed thickness 2.5 cm) were established in 2 fjords, consisting of dredged clean clay amended with powdered activated carbon (PAC) from anthracite. These active caps were compared to 2 nonactive caps in one of the fjords (designed thickness 5 cm) consisting of either clay only (i.e., without PAC) or crushed limestone. Sediment-to-water PCDD/F fluxes were measured in situ using diffusion chambers. An earlier study showed that during the first 2 years after thin-layer capping, flux reductions relative to noncapped reference fields were more extensive at the fields capped with nonactive caps (70%-90%) than at the ones with PAC-containing caps (50%-60%). However, the present work shows that between 3 and 5 years after thin-layer capping, this trend was reversed and cap effectiveness in reducing fluxes was increasing to 80% to 90% for the PAC caps, whereas cap effectiveness of the nonactive caps decreased to 20% to 60%. The increasing effectiveness over time of PAC-containing active caps is explained by a combination of slow sediment-to-PAC mass transfer of PCDD/Fs and bioturbation by benthic organisms. The decreasing effectiveness of nonactive limestone and clay caps is explained by deposition of contaminated particles on top of the caps. The present field data indicate that the capping efficiency of thin active caps (i.e., enriched with PAC) can improve over time as a result of slow diffusive PCDD/F transfer from sediment to PAC particles and better mixing of the PAC by bioturbation. Integr Environ Assess Manag 2016;12:216-221.

  • 10. Danielsson, Åsa
    et al.
    Rahm, Lars
    Brüchert, Volker
    Stockholm University, Faculty of Science, Department of Geological Sciences.
    Bonaglia, Stefano
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, Department of Geological Sciences.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Svensson, Ola
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Yekta, Sepehr Shakeri
    Reyier, Henrik
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Effects of re-oxygenation and bioturbation by the polychaete Marenzelleria arctia on phosphorus, iron and manganese dynamics in Baltic Sea sediments2018In: Boreal environment research, ISSN 1239-6095, E-ISSN 1797-2469, Vol. 23, p. 15-28Article in journal (Refereed)
    Abstract [en]

    Sediments underlying hypoxic or anoxic water bodies constitute a net source of phosphorus to the bottom water. This source has the potential to enhance eutrophication. Benthic fluxes of dissolved phosphorus, iron and manganese were measured from hypoxic, normoxic, and normoxic bioturbated by the invasive polychaete Marenzelleria arctia sediment in a mesocosm experiment. The highest benthic phosphorus efflux was detected in mesocosms with the hypoxic treatment. Normoxic, bioturbated sediments led to weaker retention of phosphorus compared to oxic, defaunated sediments. Both iron and manganese fluxes increased under bioturbated conditions compared to defaunated sediments. This study shows that re-oxygenation of previously anoxic coastal sediments enhance phosphorus retention in the sediments. Colonisation by M. arctia induce strong mobilisation of iron and manganese due to its intense bioirrigation, which facilitates organic matter degradation and decreases the phosphorus retention by metal oxides in sediment.

  • 11. Diepens, Noel J.
    et al.
    Pfennig, Sascha
    Van den Brink, Paul J.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Ruepert, Clemens
    Castillo, Luisa E.
    Effect of pesticides used in banana and pineapple plantations on aquatic ecosystems in Costa Rica2014In: Journal of environmental biology, ISSN 0254-8704, Vol. 35, no 1 (SI), p. 73-84Article in journal (Refereed)
    Abstract [en]

    Current knowledge on fate and effect of agricultural pesticides comes is mainly from temperate ecosystems. More studies are needed in tropical systems in order to assess contamination risks to non-target endemic tropical species from the extensive use of pesticides e.g. in banana and pineapple plantations. In this study, acute laboratory toxicity tests with organophosphate pesticides ethoprophos and chlorpyrifos were conducted on two Costa Rican species, cladoceran Daphnia ambigua and fish Parachromis dovii. Tests showed that chlorpyrifos was more toxic than ethoprophos to D. ambigua and P. dovii and that D. ambigua was also more sensitive than P. dovii to both pesticides. Additionally, bioassays were performed by exposing D. magna and P. dovii to contaminated water collected from the field. Chemical analyses of field water revealed that fungicides were generally the most frequent pesticide group found, followed by insecticides/nematicides and herbicides. The bioassays and values obtained from the literature confirmed that D. magna was more sensitive to pesticide contamination than P. dovii and that D. ambigua was more sensitive than D. magna, suggesting that the native cladoceran is a more suitable test species than its temperate counterpart. Species sensitivity distributions showed no significant difference in sensitivity between tropical and temperate fish and the arthropod species exposed to chlorpyrifos in this study. Choline esterase activity (ChE) was measured in P. dovii in laboratory tests in order to assess the applicability of this biomarker. ChE inhibition in P. dovii was observed in the laboratory at levels below the LC10 of both ethoprophos and chlorpyrifos, confirming that ChE is an efficient biomarker of exposure. Both indigenous Costa Rican species used in this study were found to be suitable standard tropical test species. Further studies are needed to investigate how protective the safe environmental concentrations, derived from LC50 of native tropical species, are for protecting tropical aquatic natural communities.

  • 12. Echeverría-Sáenz, Silvia
    et al.
    Mena, Freylan
    Arias-Andrés, María
    Vargas, Seiling
    Ruepert, Clemens
    Van den Brink, Paul J.
    Castillo, Luisa E.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    In situ toxicity and ecological risk assessment of agro-pesticide runoff in the Madre de Dios River in Costa Rica2018In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 25, no 14, p. 13270-13282Article in journal (Refereed)
    Abstract [en]

    The River Madre de Dios (RMD) and its lagoon is a biodiversity rich watershed formed by a system of streams, rivers, channels, and a coastal lagoon communicating with the Caribbean Sea. This basin sustains a large area of agricultural activity (mostly banana, rice, and pineapple) with intensive use of pesticides, continually detected in water samples. We investigated in situ the toxicological effects caused by pesticide runoff from agriculture and the relation of pesticide concentrations with different biological organization levels: early responses in fish biomarkers (sub-organismal), acute toxicity to Daphnia magna (organismal), and aquatic macroinvertebrate community structure. The evaluation was carried out between October 2011 and November 2012 at five sites along the RMD influenced by agricultural discharges and a reference site in a stream outside the RMD that receives less pesticides. Acute toxicity to D. magna was observed only once in a sample from the RMD (Cano Azul); the index of biomaiker responses in fish exposed in situ was higher than controls at the same site and at the RMD-Freeman. However, only macroinvertebrates were statistically related to the presence of pesticides, combined with both physical-chemical parameters and habitat degradation. All three groups of variables determined the distribution of macroinvertebrate taxa through the study sites.

  • 13.
    Granberg, Maria
    et al.
    Univ Gothenburg, Dept Marine Ecol, Kristineberg Marine Res Stn.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Hedman, Jenny
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Rosenberg, Rutger
    Univ Gothenburg, Dept Marine Ecol, Kristineberg Marine Res Stn.
    Jonsson, Per
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bioturbation-Driven Release of Organic Contaminants from Baltic Sea Sediments Mediated by the Invading Polychaete Marenzelleria neglecta.2008In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 42, no 4, p. 1058-1065Article in journal (Refereed)
    Abstract [en]

    Baltic Sea sediments are among the world’s most polluted regarding eutrophication and contamination. Eutrophication-induced hypoxia has caused depletion of bioturbating macrofauna in vast areas, producing laminated sediments. We investigated if reoxygenation and colonization by the invading deep-burrowing polychaete Marenzelleria neglecta may cause an augmented contaminant release from Baltic Sea sediments. Intact laminated sediment cores were exposed either to in situ hypoxia, reoxygenation, or reoxygenation combined with bioturbating M. neglecta. The release fluxes of particle-associated (NPart) and dissolved (NDiss) PCBs and chlorinated pesticide residues (POPs) were quantified (GC-ECD) after 85 d along with contaminant concentrations in sediment and biota. Lavoisier-based mass transfer coefficients (Kf) were calculated from NDiss. Sediment contaminant concentrations were high (ΣPCB7: 42–52 ng gsediment−1 dw) due to emissions from Stockholm. NDiss always exceeded NPart by an order of magnitude. Bioturbation enhanced NDiss and Kf from hypoxic sediments 0.7 – 3 times while reoxygenation alone had no significant effect. M. neglecta accumulated low amounts of contaminants but significantly stimulated aquatic release of bioavailable sequestered contaminants. Bioturbation should be included in aquatic contaminant fate models. We advise to consider quiescent pollutant sources and possible ecological shifts when aiming to restore eutrophicated aquatic environments.

  • 14.
    Gunnarsson, Jonas
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Svensson, Ola
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Kraftig ökning av Marenzelleria2012Other (Other (popular science, discussion, etc.))
  • 15.
    Hedman, Jenny E.
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Bradshaw, Clare
    Thorsson, Maria H.
    Gilek, Michael
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Fate of contaminants in Baltic Sea sediments: role of bioturbation and settling organic matter2008In: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 356, p. 25-38Article in journal (Refereed)
    Abstract [en]

    This experimental study examined the interactive effects of bioturbation and settling organic matter (OM) on the fate (burial and remobilisation) of 2 surface-deposited contaminants in Baltic Sea sediment: the metal Cd and a hydrophobic organic pollutant, the flame retardant BDE-99. Three macrofaunal species with diverse feeding and bioturbation strategies were used: the amphipod Monoporeia affinis, the clam Macoma balthica and the polychaete Marenzelleria spp. Radiolabelled contaminants were added to the sediment surface in association with 3 different OM types: (1) phytoplankton, (2) terrestrial lignin and (3) Baltic sediment. Bioturbation by all species increased the retention of both contaminants in the sediment, most effectively M. affinis and M. balthica. A decoupled transport of Cd and BDE-99 by Marenzelleria was observed. Generally, Marenzelleria buried the highest amount of Cd into the sediment but also caused the highest remobilisation to the water, indicating an effective transport of (soluble) Cd over the sediment-water interface via bio-irrigation. Lack of the highly hydrophobic and mainly particle-associated BDE-99 below the sediment surface suggests that Marenzelleria caused no significant particle mixing. The addition of various OM types significantly affected the distribution of Cd, but not of BDE-99. There was an interactive effect between bioturbation (species) and OM type, generally showing an increased burial and release of Cd when associated with phytoplankton in the presence of Marenzelleria. Our results emphasise the importance of understanding the complex interactions between ecological (e.g. infaunal feeding and bioturbation activities) and physiochemical processes (contaminant speciation and sorption kinetics) when assessing the fate of contaminants in aquatic ecosystems.

  • 16. Hedman, Jenny E.
    et al.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Samuelsson, Göran
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gilbert, Franck
    Particle reworking and solute transport by the sediment-living polychaetes Marenzelleria neglecta and Hediste diversicolor2011In: Journal of Experimental Marine Biology and Ecology, ISSN 0022-0981, E-ISSN 1879-1697, Vol. 407, no 2, p. 294-301Article in journal (Refereed)
    Abstract [en]

    This experimental study quantified and compared particle-mixing and solute transport by the polychaetes Marenzelleria neglecta (2 g ww, 3200 ind.m(-2)) and Hediste diversicolor (2 g ww, 800 ind.m(-2)) in Baltic Sea sediments. Particle tracers (luminophores) were added to the sediment surface and their vertical distribution in the sediment was measured after 10 d. The rate of particle mixing was quantified using a gallery-diffusion model calculating the biodiffusion coefficient D(b) and the non-local transport parameter r. Bioirrigation was measured by adding an inert solute tracer (bromide) to the overlying water 1, 1.5 and 2 d before the end of the experiment, and quantified by calculating the net bromide flux and fitting the bromide profiles to a 1D diffusion model providing an apparent biodiffusion coefficient D(a). The two polychaete worms displayed similar particle-mixing and solute transport efficiencies (based on total biomass) despite different modes of bioturbation. However, H. diversicolor was a more efficient particle-reworker and M. neglecta a more efficient bioirrigator, on an individual level. H. diversicolor buried a higher percentage (13%) of luminophores below the top 0.5 cm surface layer than M. neglecta (6%). D(b) did not differ between the two species (2.4 x 10(-3) cm(2) d(-1)) indicating a similar rate of diffusive mixing of the top sediment, however, the non-local transport parameter r was 2.5 y(-1) for H. diversicolor and zero for M. neglecta, suggesting no significant particle-transport below the biodiffusive layer by M. neglecta. The average individual net bromide fluxes obtained were ca. 0.01 mL min(-1) for H. diversicolor and 0.003 mL min(-1) for M. neglecta, corresponding to an area-specific rate of ca. 12 L m(-2) d(-1) at the used densities. D(a) did not differ between the two polychaetes, suggesting a higher individual solute exchange efficiency of M. neglecta considering the much higher ventilation rates reported for H. diversicolor than for Marenzelleria sp. The ongoing colonization of Baltic Sea sediments by M. neglecta at high densities may thus lead to an enhanced soluble release of both nutrients and contaminants. These results add information to the understanding of the potential effects of the invasion of M. neglecta on sediment biogeochemistry when competing with and/or replacing native species.

  • 17.
    Hedman, Jenny E
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Stempa Tocca, Julia
    Gunnarsson, Jonas S
    Remobilization of PCB from Baltic Sea sediment: comparing the roles of bioturbation and physical resuspension2009In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 28, no 11, p. 2241-2249Article in journal (Refereed)
    Abstract [en]

    The release of a 14C-labeled trichlorobiphenyl compound ([14C]PCB 32) from sediment to water was quantified weekly in a 30-d microcosm experiment with recirculating water. Two modes of bioturbation-driven polychlorinated biphenyl (PCB) release—bioturbation by the amphipod Monoporeia affinis (a particle biodiffuser) and bioturbation by the polychaete Marenzelleria sp. (a bioirrigator)—were compared to the PCB release caused by physical resuspension of the sediment generated by a motor-driven paddle used twice a week. Bioturbation by the amphipod M. affinis caused a significantly higher remobilization of both particle-associated PCB (PCBpart) and dissolved PCB (PCBdiss) than the other treatments. Bioturbation by Marenzelleria sp. and physical resuspension caused a similar release of PCBdiss despite a significantly higher amount of total suspended solids in the water column after physical resuspension. In all treatments, the release of PCBdiss was more than one order of magnitude higher than that of PCBpart, indicating a significant potential route of exposure for pelagic organisms, such as fish, to the most bioavailable PCB form. Calculated mass-transfer coefficients (0.3–1.3 cm/d) correspond to previously reported values for trichlorinated PCBs. The present results indicate that biological reworking of sediments can be just as, or even more, important than physical resuspension for the remobilization of sediment-bound contaminants.

  • 18. Josefsson, Sarah
    et al.
    Leonardsson, Kjell
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Wiberg, Karin
    Bioturbation-Driven Release of Buried PCBs and PBDEs from Different Depths in Contaminated Sediments2010In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, no 19, p. 7456-7464Article in journal (Refereed)
    Abstract [en]

    Bioturbation can remobilize previously buried contaminants, leading to an increased exposure of aquatic biota. The remobilization of buried polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) from three different sediment depth layers (2.0-2.5 cm, 5.0-5.5 cm, and 10.0-10.5 cm) was studied in a laboratory experiment with two benthic macrofauna species, the amphipod Monoporeia affinis and the polychaete Marenzelleria spp. Remobilization of PCBs and PBDEs was significantly higher in the presence of Marenzelleria spp. than in M. affinis treatments and controls (without macrofauna). The highest remobilization occurred from the most shallow layers (2.0-2.5 cm > 5.0-5.5 cm > 10.0-10.5 cm), but contaminants were remobilized due to bioturbation from layers down to at least 10 cm. Congeners with lower hydrophobicity were remobilized to a higher extent than more hydrophobic congeners. The contaminant distribution between the particulate and the dissolved phase in the water column depended on hydrophobicity and burial depth of the contaminant, with congeners from deeper layers displaying an increased distribution to the particulate phase. Release fluxes and sediment-to-water mass transfer coefficients (MTCs) show that bioturbation by the polychaete Marenzelleria spp. can lead to a significant remobilization of buried contaminants from Baltic Sea sediments.

  • 19. Josefsson, Sarah
    et al.
    Leonardsson, Kjell
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Wiberg, Karin
    Influence of contaminant burial depth on the bioaccumulation of PCBs and PBDEs by two benthic invertebrates (Monoporeia affinis and Marenzelleria spp.)2011In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 85, no 9, p. 1444-1451Article in journal (Refereed)
    Abstract [en]

    The bioaccumulation of buried polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) added to specific depths in sediment (2.0-2.5, 5.0-5.5 and 10.0-10.5 cm) was studied in two infaunal species with similar feeding habits (surface deposit-feeders) but different bioturbation modes. The deep-burrowing polychaetes Marenzelleria spp. (Mz) displayed up to 36 times higher tissue concentrations of buried (spiked) contaminants than the surface-dwelling biodiffusing amphipod Monoporeia affinis. The differences in bioaccumulation were most pronounced for less hydrophobic contaminants due to the bioirrigating activity of Mz. Contaminants buried at shallow depths displayed higher accumulation than more deeply buried contaminants. In contrast, the bioaccumulation of unspiked (native) contaminants with a unifo vertical distribution in the sediment was similar between the species. For Mz, the BSAFs increased with increased K(ow) for the uniformly distributed contaminants, but decreased for the buried contaminants, which indicates that the dominant uptake routes of the buried contaminants can differ from the uniformly distributed contaminants. The surface sediment concentration of buried contaminants increased in Mz treatments, showing that Mz bioturbation can remobilize historically buried contaminants to the biologically active surface layer and increase the exposure for surface-dwelling species.

  • 20. Josefsson, Sarah
    et al.
    Schaanning, Morten
    Samuelsson, Göran S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Olofsson, Ida
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Eek, Espen
    Wiberg, Karin
    Capping Efficiency of Various Carbonaceous and Mineral Materials for In Situ Remediation of Polychlorinated Dibenzo-p-dioxin and Dibenzofuran Contaminated Marine Sediments: Sediment-to-Water Fluxes and Bioaccumulation in Boxcosm Tests2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 6, p. 3343-3351Article in journal (Refereed)
    Abstract [en]

    The efficiency of thin-layer capping in reducing sediment-to-water fluxes and bioaccumulation of polychlorinated dibenzo-p-dioxins and dibenzofurans, hexachlorobenzene, and octachlorostyrene was investigated in a boxcosm experiment. The influence of cap thickness (0.5-5 cm) and different cap materials was tested using a three-factor experimental design. The cap materials consisted of a passive material (coarse or fine limestone or a marine clay) and an active material (activated carbon (AC) or kraft lignin) to sequester the contaminants. The cap thickness and the type of active material were significant factors, whereas no statistically significant effects of the type of passive material were observed. Sediment-to-water fluxes and bioaccumulation by the two test species, the surface-dwelling Nassarius nitidus and the deep-burrowing Nereis spp., decreased with increased cap thickness and with addition of active material. Activated carbon was more efficient than lignin, and a similar to 90% reduction of fluxes and bioaccumulation was achieved with 3 cm caps with 3.3% AC. Small increases in fluxes with increased survival of Nereis spp. indicated that bioturbation by Nereis spp. affected the fluxes.

  • 21. Mena, F.
    et al.
    Azzopardi, M.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Pfennig, S.
    Ruepert, C.
    Tedengren, Michael
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Castillo, L. E.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Use of cholinesterase activity as a biomarker of pesticide exposure used on Costa Rican banana plantations in the native tropical fish Astyanax aeneus (Gunther, 1860)2014In: Journal of environmental biology, ISSN 0254-8704, Vol. 35, no 1 (SI), p. 35-42Article in journal (Refereed)
    Abstract [en]

    In Costa Rica, thousands of tones of agricultural pesticides have been used for decades and their use is continuously increasing due to intensive and expanding production of coffee, pineapple, rice, ornamental plants and bananas. The objective of this study was to evaluate whether choline esterase (ChE) activity could be used as a biomarker of exposure to pesticides in the Costa Rican native fish Astyanax aeneus (characidae). Three methods used in order to evaluate the ChE biomarker were as follows: Laboratory studies where A. aeneus was exposed to organophosphate pesticide (ethoprophos); In situ 48 hr exposure assessment using caging experiments with fish exposed upstream and downstream of banana plantations and ChE activity estimation of in fish captured directly at sites with different degrees of pesticide exposure. Results from the laboratory studies showed that ChE activity in both brain and muscle tissue was significantly lower in fish exposed to ethoprophos than in controls. Fish from the caging experiments showed no difference in ChE activity neither in brain nor in muscle tissue between the four tested sites and was attributed to the short duration of the exposure. A significant difference in ChE activity was determined in muscle of fish captured from Laguna Madre de Dios compared to fish from Canal Batan. Although our laboratory results revealed that ChE activity in A. aeneus was highly responsive to ethoprophos, results from field experiments were less conclusive and showed that the captured fish showed large variability in ChE activity and that more research is needed before ChE activity can be used as reliable biomarker of pesticide exposure.

  • 22.
    Näslund, J.
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Samuelsson, Göran S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Nascimento, Francisco J. A.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Nilsson, H. C.
    Cornelissen, Gerard
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Schaanning, M. T.
    Ecosystem effects of materials proposed for thin-layer capping of contaminated sediments2012In: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 449, p. 27-U46Article in journal (Refereed)
    Abstract [en]

    Ecotoxicological effects of 2 carbonaceous and 7 mineral capping materials suggested for in situ remediation of contaminated sediments in the Grenland fjords, Norway, were investigated in a mesocosm experiment. The primary objective was to compare the various materials with regard to potentially harmful effects on the benthic ecosystem. The materials assessed were activated carbon, Kraft-lignin, sand and clay materials, and 3 industrial by-products. Using sediment box-core samples with intact benthic communities, effects on structural (bacterial, macro-and meiofauna diversity) and functional (sediment-to-water nutrient fluxes, oxygen fluxes and bacterial production) endpoints were assessed. Significant deviations from the control (no capping) were detected for all of the tested materials for at least one endpoint. Generally, materials similar to the indigenous sediment (clay, sand) had relatively low deviations from the control, whereas industrial products (plaster, 2 types of crushed marble) resulted in deviations for most endpoints and large reductions in community richness and abundance. For example, at the end of the experimental period, the number of macrofauna taxa was <10 in these treatments, compared to >27 in uncapped mesocosm and field control sediments. The results from the study show that reducing harmful ecosystem effects from thin-layer capping by selecting capping materials based on robust, multi-endpoint mesocosm bench-tests is both possible and recommendable. Potential ecosystem impacts are particularly important to consider when large areas and areas with adequate ecological status are considered for thin-layer capping.

  • 23.
    Näslund, Johan
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Nascimento, Francisco
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Meiofauna reduces bacterial mineralization of naphthalene in marine sediment2010In: The ISME journal, ISSN 1751-7362, no 4, p. 1421-1430Article in journal (Refereed)
    Abstract [en]

    The role of sediment-living meiofauna, benthic invertebrates smaller than 1000lm, such as nematodes and ostracods, on the mineralization of naphthalene, a common polycyclic aromatic hydrocarbon (PAH), in marine sediment was studied in microcosms using radiorespirometry. A method to extract live meiofauna was developed and used in order to experimentally manipulate meiofauna abundance and group diversity. Higher abundances of meiofauna were found to significantly decrease naphthalene mineralization. Furthermore, a change in the bacterial community composition (studied using terminal restriction fragment length polymorphism) was also observed in presence of higher meiofauna abundance, as well as a lower number of cultivable naphthalene-degrading bacteria. The reduced mineralization of naphthalene and the altered bacterial community composition in the presence of increased meiofauna abundance is likely the result of top-down control by meiofauna. This study shows that higher abundances of meiofauna can significantly decrease the microbial mineralization of PAHs such as naphthalene and also significantly modify the bacterial community composition in natural marine sediments.

  • 24. Quintana, Cintia O.
    et al.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Nascimento, Francisco J. A.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Bonaglia, Stefano
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Forster, Stefan
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Kristensen, Erik
    Functional Performance of Three Invasive Marenzelleria Species Under Contrasting Ecological Conditions Within the Baltic Sea2018In: Estuaries and Coasts, ISSN 1559-2723, E-ISSN 1559-2731, Vol. 41, no 6, p. 1766-1781Article in journal (Refereed)
    Abstract [en]

    A 4-week laboratory experiment investigated the behaviour (survival and bioirrigation) and impact of the invasive polychaetes Marenzelleria viridis, M. neglecta and M. arctia on sediment-water solutes exchange, porewater chemistry, and Fe and P interactions in high-salinity sandy sediment (HSS) and low-salinity muddy sediment (LSM) from the Baltic Sea. M. viridis showed deep burrowing with efficient bioirrigation (11 L m−2 day−1) and high survival (71%) in HSS, while M. arctia exhibited shallow burrowing with high bioirrigation (12 L m−2 day−1) and survival (88%) in LSM. M. neglecta behaved poorly in both ecological settings (bioirrigation, 5–6 L m−2 day−1; survival, 21–44%). The deep M. viridis bioirrigation enhanced total microbial CO2 (TCO2) production in HSS by 175% with a net efflux of NH4+ and PO43−, at rates 3- to 27-fold higher than for the other species. Although the shallow and intense bioirrigation of M. arctia in LSM stimulated microbial TCO2 production to some extent (61% enhancement), the nutrient fluxes close to zero indicate that it effectively prevented the P release. Porewater Fe:PO43− ratios revealed that the oxidizing effect of M. arctia bioirrigation increased the PO43− adsorption capacity of LSM twofold relative to defaunated controls while no buffering of PO43− was detected in M. viridis HSS treatment. Therefore, the different behaviour of the three species in various environments and the sharp contrast between M. viridis and M. arctia effects on C, N and P cycling must be considered carefully when the ecological role of Marenzelleria species in the Baltic Sea is evaluated.

  • 25.
    Raymond, Caroline
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Svensson, Ola
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gunnar, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Cederwall, Hans
    Widbom, Bertil
    Högskolan på Gotland.
    Miljöövervakning av mjukbottenfauna i Gotlands kustområden: Områdena mellan När och Östergarn, samt Slite, Klintehamn och Fårösund2012Report (Other (popular science, discussion, etc.))
  • 26.
    Raymond, Caroline
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Svensson, Ola
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Agrenius, Stefan
    Göteborgs universitet.
    Albertsson, Jan
    Umeå universitet.
    Makrofauna mjukbotten: Bottendjursamhällets status 20112012In: Havet - om miljötillståndet i Svenska Havsområden, ISSN 1654-6741, p. 60-63Article in journal (Other (popular science, discussion, etc.))
  • 27.
    Raymond, Caroline
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Svensson, Ola
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Cederwall, Hans
    Mjukbottenfauna i Stockholms skärgård: Regional miljöövervakning 20112012Report (Other (popular science, discussion, etc.))
  • 28. Rosenberg, Rutger
    et al.
    Davey, E
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Norling, Karl
    Frank, M
    Application of computer-aided tomography to visualize and quantify biogenic structures in marine sediments2007In: Marine Ecology Progress Series, Vol. 331, p. 23-34Article in journal (Refereed)
  • 29.
    Rämö, Robert A.
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    van den Brink, Paul J.
    Ruepert, Clemens
    Castillo, Luisa E.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Environmental risk assessment of pesticides in the River Madre de Dios, Costa Rica using PERPEST, SSD, and msPAF models2018In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 25, no 14, p. 13254-13269Article in journal (Refereed)
    Abstract [en]

    This study assesses the ecological risks (ERA) of pesticides to aquatic organisms in the River Madre de Dios (RMD), which receives surface runoff water from banana, pineapple, and rice plantations on the Caribbean coast of Costa Rica. Water samples collected over 2 years at five sites in the RMD revealed a total of 26 pesticides. Their toxicity risk to aquatic organisms was assessed using three recent ERA models. (1) The PERPEST model showed a high probability (>50 %) of clear toxic effects of pesticide mixtures on algae, macrophytes, zooplankton, macroinvertebrates, and community metabolism and a low probability (<50 %) of clear effects on fish. (2) Species sensitivity distributions (SSD) showed a moderate to high risk of three herbicides: ametryn, bromacil, diuron and four insecticides: carbaryl, diazinon, ethoprophos, terbufos. (3) The multi-substance potentially affected fraction (msPAF) model showed results consistent with PERPEST: high risk to algae (maximum msPAF: 73 %), aquatic plants (61 %), and arthropods (25 %) and low risk to fish (0.2 %) from pesticide mixtures. The pesticides posing the highest risks according to msPAF and that should be substituted with less toxic substances were the herbicides ametryn, diuron, the insecticides carbaryl, chlorpyrifos, diazinon, ethoprophos, and the fungicide difenoconazole. Ecological risks were highest near the plantations and decreased progressively further downstream. The risk to fish was found to be relatively low in these models, but water samples were not collected during fish kill events and some highly toxic pesticides known to be used were not analyzed for in this study. Further sampling and analysis of water samples is needed to determine toxicity risks to fish during peaks of pesticide mixture concentrations. The msPAF model, which estimates the ecological risks of mixtures based on their toxic modes of action, was found to be the most suitable model to assess toxicity risks to aquatic organisms in the RMD. The PERPEST model was found to be a strong tool for screening risk assessments. The SSD approach is useful in deriving water quality criteria for specific pesticides. This study, through the application of three ERA models, clearly shows that pesticides used in plantations within the RMD watershed are expected to have severe adverse effects on most groups of aquatic organisms and that actions are urgently needed to reduce pesticide pollution in this high biodiversity ecosystem.

  • 30.
    Samuelsson, Göran S.
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Hedman, Jenny E.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Elmquist Kruså, Marie
    Norwegian Geotechnical Institute (NGI).
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Cornelissen, Gerard
    Norwegian Geotechnical Institute (NGI).
    Reduced bioaccumulation of PCBs and PAHs by sediment fauna following in situ remediation with activated carbon in Trondheim Harbor (Norway)Manuscript (preprint) (Other academic)
    Abstract [en]

    Thin-layer capping with activated carbon (AC) was deployed in experimental plots in Trondheim harbor, Norway, using caps containing AC+clay, AC-only or AC+sand. Intact sediment cores were collected from the in situ remediated plots to study the capping efficiency of the various AC treatments in reducing the aqueous concentrations and the bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in the polychaete Hediste diversicolor and the clam Abra nitida. Reduced aqueous concentrations were observed in all AC-treatments, but generally AC+clay appeared to be superior to the other tested treatments. Capping efficiency by AC+clay, in terms of reduced bioaccumulation of PAHs and PCBs, ranged between 40 % and 87% in the worms and between 67% and 97% in the clams. Sediment capped with AC-only also led to reduced bioaccumulation of PCBs, while AC+sand showed no reduction in bioaccumulation. The worms had lower relative lipid content in the AC-only treatment after exposure.

  • 31.
    Samuelsson, Göran S.
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Hedman, Jenny E.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Krusa, Marie Elmquist
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Cornelissen, Gerard
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Capping in situ with activated carbon in Trondheim harbor (Norway) reduces bioaccumulation of PCBs and PAHs in marine sediment fauna2015In: Marine Environmental Research, ISSN 0141-1136, E-ISSN 1879-0291, Vol. 109, p. 103-112Article in journal (Refereed)
    Abstract [en]

    Three types of thin-layer caps with activated carbon (AC) were tested in situ in experimental plots (10 x 10 m) in Trondheim harbor, Norway, using AC + clay, AC-only or AC + sand. One year after capping, intact sediment cores were collected from the amended plots for ex situ surveys of the capping efficiency in reducing the PAH and PCB aqueous concentrations and bioaccumulation by the polychaete Hediste diversicolor and the clam Abra nitida. Reduced pore water concentrations were observed in all AC treatments. The capping efficiency was in general AC + clay > AC-only > AC + sand. AC + clay reduced bioaccumulation of PAH and PCB congeners between 40% and 87% in the worms and between 67% and 97% in the clams. Sediment capped with AC-only also led to reduced bioaccumulation of PCBs, while AC + sand showed no reduction in bioaccumulation. Thus the best thin-layer capping method in this study was AC mixed with clay.

  • 32.
    Samuelsson, Göran S.
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Svensk Ekologikonsult, Sweden.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Agrenius, Stefan
    Schaanning, Morten
    Cornelissen, Gerard
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Response of marine benthic fauna to thin-layer capping with activated carbon in a large-scale field experiment in the Grenland fjords, Norway2017In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 24, no 16, p. 14218-14233Article in journal (Refereed)
    Abstract [en]

    A field experiment with thin-layer capping was conducted in the Grenland fjords, Norway, for remediation in situ of mercury and dioxin-contaminated sediments. Experimental fields at 30 and 95 m depth were capped with (i) powdered activated carbon (AC) mixed with clay (AC+clay), (ii) clay, and (iii) crushed limestone. Ecological effects on the benthic community and species-feeding guilds were studied 1 and 14 months after capping, and a total of 158 species were included in the analyses. The results show that clay and limestone had only minor effects on the benthic community, while AC+clay caused severe perturbations. AC+clay reduced the abundance, biomass, and number of species by up to 90% at both 30 and 95 m depth, and few indications of recovery were found during the period of this investigation. The negative effects of AC+clay were observed on a wide range of species with different feeding strategies, although the suspension feeding brittle star Amphiura filiformis was particularly affected. Even though activated carbon is effective in reducing sediment-to-water fluxes of dioxins and other organic pollutants, this study shows that capping with powdered AC can lead to substantial disturbances to the benthic community.

  • 33.
    Samuelsson, Göran S.
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Agrenius, Stefan
    Schaanning, Morten
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Large-scale field study on thin-layer capping of dioxin contaminated sediments in the Grenland fjords, Norway: Effects on marine benthic faunaManuscript (preprint) (Other academic)
    Abstract [en]

    The Grenland fjords on the South East Coast of Norway are heavily contaminated with dioxins and furans after emissions from past industrial activities. Thin layer capping with a 1.1 to 3.7 cm cap was tested as a remediation option in a large-scale in situ study in two different parts of the fjord system, in the Ormefjord at 25-30 meters depth and in the Eidangerfjord at 80-100 meters depth. Three different capping materials: Limestone gravel, Clay, and powdered activated carbon (AC) mixed into clay (AC+clay) was compared to untreated reference fields in order to evaluate their effects on contaminant sequestering and possible effects on the benthic communities. Sediment to water fluxes of contaminants were significantly reduced by the capping materials, especially with AC-clay and is reported in a companion study.This study discusses the ecological effects of the remediation 1 and 14 months post treatment. Capping with Clay and Lime had minor and short-lasting effects on benthic fauna. Capping with AC+clay, however, had led to profound and more long-lasting perturbations of the macrofauna. An initial massive decline in filter feeders and suspension feeders was observed after 1 month in the shallower Ormefjord. The negative effects got worse after 14 months and resulted in dramatic reductions of all feeding guilds. The number of species, organism abundances and biomass in the AC+clay field were ca 80-90 % lower compared to the reference fields after 14 months.The negative effects were less pronounced at the deeper (80-100 meters) location in the Eidangerfjord and were also stable with time, suggesting that the benthic community the deeper habitat was more resilient to the capping compared to the shallower community in Ormefjord.The differences in response of the two communities are hypothesized to be due to the higher macrofaunal diversity in the deeper location, as well as to differences in abiotic factors such as available food and temperature. Results from this study show that amendment with powdered AC can lead to serious perturbations of the benthic community, at least initially, i.e. one year post capping in this study. These results stresses that further long-term monitoring of these benthic communities is necessary before capping with AC+clay could be advocated as a potential remediation option.

  • 34.
    Sanderson Bellamy, Angelina
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Svensson, Ola
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    van den Brink, Paul
    Wageningen University, Department of Aquatic Ecology and Water Quality Management.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Tedengren, MIchael
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Insect diversity on high-input, low-input and organic banana farmsIn: Agricultural and Forest Entomology, ISSN 1461-9555, E-ISSN 1461-9563Article in journal (Refereed)
    Abstract [en]

    High intensity of pesticide use in banana production is problematic not only for human health and the surrounding environment, but can threaten the provision of ecosystem services on which farm productivity depends. This research investigates the effects of varying pesticide-use intensities on on-farm insect diversity, using three different types of farm management systems: high pesticide input conventional system, reduced pesticide input conventional system and organic system. Insect sampling was done using pitfall and yellow bowl traps, left for a 24-hour period at 2 locations inside the banana farm, at the edge of the farm, and in adjacent forest. Species were classified to family level and then morphospecies. Insect species community composition and diversity were compared using multivariate statistics with ordination analysis and Monte Carlo permutation testing, and revealed that each of the management systems were significantly different from each other for both trap types. Insect diversity decreased as production management increased its pesticide use. Reduced insect diversity resulted in fewer functional groups and fewer insect families assuming different functions essential to ecosystem health. Organic farms had similar species composition on the farm compared to adjacent forest sites, whereas species composition increasingly differed between farm and forest sites as pesticide-use intensity increased. We conclude that while organic production has minimal impact on insect biodiversity, even small reductions in pesticide-use intensity can have a significantly positive impact on on-farm insect biodiversity and functional roles supported.

  • 35. Sanderson Bellamy, Angelina
    et al.
    Svensson, Ola
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    van den Brink, Paul J.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Tedengren, Michael
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Insect community composition and functional roles along a tropical agricultural production gradient2018In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 25, no 14, p. 13426-13438Article in journal (Refereed)
    Abstract [en]

    High intensity agricultural production systems are problematic not only for human health and the surrounding environment, but can threaten the provision of ecosystem services on which farm productivity depends. This research investigates the effects of management practices in Costa Rica on on-farm insect diversity, using three different types of banana farm management systems: high-input conventional system, low-input conventional system, and organic system. Insect sampling was done using pitfall and yellow bowl traps, left for a 24-h period at two locations inside the banana farm, at the edge of the farm, and in adjacent forest. All 39,091 individual insects were classified to family level and then morphospecies. Insect species community composition and diversity were compared using multivariate statistics with ordination analysis and Monte Carlo permutation testing, and revealed that each of the management systems were significantly different from each other for both trap types. Insect diversity decreased as management intensity increased. Reduced insect diversity resulted in fewer functional groups and fewer insect families assuming different functions essential to ecosystem health. Organic farms had similar species composition on the farm compared to adjacent forest sites, whereas species composition increasingly differed between farm and forest sites as management intensity increased. We conclude that while organic production has minimal impact on insect biodiversity, even small reductions in management intensity can have a significantly positive impact on on-farm insect biodiversity and functional roles supported.

  • 36. Selck, Henriette
    et al.
    Adamsen, Peter B.
    Backhaus, Thomas
    Banta, Gary T.
    Bruce, Peter K. H.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Burton, G. Allen
    Butts, Michael B.
    Boegh, Eva
    Clague, John J.
    Dinh, Khuong V.
    Doorn, Neelke
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Hauggaard-Nielsen, Henrik
    Hazlerigg, Charles
    Hunka, Agnieszka D.
    Jensen, John
    Lin, Yan
    Loureiro, Susana
    Miraglia, Simona
    Munns, Wayne R.
    Nadim, Farrokh
    Palmqvist, Annemette
    Rämö, Robert A.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Seaby, Lauren P.
    Syberg, Kristian
    Tangaa, Stine R.
    Thit, Amalie
    Windfeld, Ronja
    Zalewski, Maciej
    Chapman, Peter M.
    Assessing and managing multiple risks in a changing worldThe Roskilde recommendations2017In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 36, no 1, p. 7-16Article in journal (Refereed)
    Abstract [en]

    Roskilde University (Denmark) hosted a November 2015 workshop, Environmental RiskAssessing and Managing Multiple Risks in a Changing World. This Focus article presents the consensus recommendations of 30 attendees from 9 countries regarding implementation of a common currency (ecosystem services) for holistic environmental risk assessment and management; improvements to risk assessment and management in a complex, human-modified, and changing world; appropriate development of protection goals in a 2-stage process; dealing with societal issues; risk-management information needs; conducting risk assessment of risk management; and development of adaptive and flexible regulatory systems. The authors encourage both cross-disciplinary and interdisciplinary approaches to address their 10 recommendations: 1) adopt ecosystem services as a common currency for risk assessment and management; 2) consider cumulative stressors (chemical and nonchemical) and determine which dominate to best manage and restore ecosystem services; 3) fully integrate risk managers and communities of interest into the risk-assessment process; 4) fully integrate risk assessors and communities of interest into the risk-management process; 5) consider socioeconomics and increased transparency in both risk assessment and risk management; 6) recognize the ethical rights of humans and ecosystems to an adequate level of protection; 7) determine relevant reference conditions and the proper ecological context for assessments in human-modified systems; 8) assess risks and benefits to humans and the ecosystem and consider unintended consequences of management actions; 9) avoid excessive conservatism or possible underprotection resulting from sole reliance on binary, numerical benchmarks; and 10) develop adaptive risk-management and regulatory goals based on ranges of uncertainty. Environ Toxicol Chem 2017;36:7-16.

  • 37.
    Stadlinger, Nadja
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Faculty of Science, Department of Physical Geography.
    Berg, Håkan
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Van den Brink, Paul J.
    Tam, Nguyen T.
    Stockholm University, Faculty of Science, Department of Physical Geography. Nong Lam University, Vietnam.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Comparison of predicted aquatic risks of pesticides used under different rice-farming strategies in the Mekong Delta, Vietnam2018In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 25, no 14, p. 13322-13334Article in journal (Refereed)
    Abstract [en]

    This study evaluates the risks of pesticides applied in rice-fish and rice farming, with and without integrated pest management (IPM) strategies, to non-target aquatic organisms in two provinces of the Mekong Delta, Vietnam. Pesticide inventories and application patterns were collected from 120 Vietnamese farmers through interviews. Risks were assessed using (1) Pesticide RIsks in the Tropics to Man, Environment, and Trade (PRIMET), a first-tier model, which calculates predicted environmental concentrations (PECs) of pesticides in the rice field, based on the compound's physico-chemical properties and the application pattern, and then compares the PECs to safe concentrations based on literature data, and (2) species sensitivity distribution (SSD), a second-tier assessment model using species sensitivity distributions to calculate potentially affected fraction (PAF) of species based on the PECs from PRIMET. Our results show that several of the used insecticides pose a high risk to fish and arthropods and that the risks are higher among rice farmers than among rice-fish farmers. This study indicates that the PRIMET model in combination with SSDs offer suitable approaches to help farmers and plant protection staff to identify pesticides that may cause high risk to the environment and therefore should be substituted with safer alternatives.

  • 38.
    Svensson, Ola
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Cederwall, Hans
    Baltic Bentos.
    Regional miljöövervakning av mjukbottenfauna i Östergötlands skärgård år 20112012Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Denna rapport presenterar resultaten av 2011 års undersökning av mjukbottenfaunan i Östergötlands skärgård. Undersökningen är en del av det regionalt-nationellt samordnade miljöövervakningsprogrammet som startade år 2007. 20 stationer belägna på djup mellan 10 och 38 meter undersöks årligen avseende bottenfauna och sedimentkvalité. Av dessa 20 stationer ligger hälften i S:t Annas skärgård (kluster REG St Anna) och hälften i Gryts skärgård (kluster REG Gryt) (Fig. 1). Stationerna är belägna i 5 olika vattenförekomster enligt SMHI:s indelning. Av stationerna i S:t Annas skärgård ligger 9 st i vattenförkomsten Kärrfjärden, medan 1 station ligger i Finnfjärden. Av stationerna i Gryts skärgård ligger 5 st i Hesselöfjärden, 3 st i Orren och 2 st i Ytteröområdet. Två stationer har provtagits tidigare på uppdrag av Motala Ströms Vattenvårdsförbund (Stn Bf 34b och stn Bf 32). Data från dessa redovisas även separat för att illustrera långtidsförändringar.

    Huvudfokus för undersökningen är statusbedömning av bottensamhället med hjälp av Benthic Quality Index (BQI). Statusen för klustret REG St Anna bedöms år 2011 som måttlig efter tre år med god status. I klustret REG Gryt bedöms statusen alltjämt som god. År 2011 beräknades BQI-värdet (20:e percentilen) för klustret REG St Anna till 3,6. Detta är en försämring sedan 2010 (20:e percentilen av BQI=4,5) men värdet är högre än det som noterades för 2007 (2,8), dvs vid programmets start. I klustret REG Gryt har BQI-värdet ökat från 5,9 till 6,2 sen förra året. Vid en jämförelse med värdet för 2007 har områdets BQI-värde minskat från ett mycket högt BQI-värde på 8,2.

    Den biologiska mångfalden, uttryckt som totalt antal taxa, har minskat något sedan föregående år inom båda klustren. Medelantalet taxa har också minskat i REG St Anna, medan en svag ökning kan noteras för REG Gryt. Just det minskade antalet taxa i REG St Anna utgör den största orsaken till områdets lägre BQI-värde. De taxa som försvunnit har tidigare endast förekommit med ett fåtal individ och på enstaka stationer. Den största förändringen i bottenfaunasammansättningen sedan förra året är en markant ökning av den för Östersjön relativt nya havsborstmasken Marenzelleria spp. i REG Gryt.

    Sammanfattningsvis har statusen försämrats till måttlig i REG St Anna men i REG Gryt är statusen fortsatt god.

  • 39.
    Svensson, Ola
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Raymond, Caroline
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Cederwall, Hans
    Regional miljöövervakning av mjukbottenfaunai Askö-Landsortsområdet år 20112012Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Denna rapport redovisar resultaten av 2011 års undersökning av mjukbottenfaunan i Askö-Landsortsområdet. 20 stationer belägna på djup mellan 9 och 60 meter undersöks årligenavseende bottenfauna och sedimentkvalité. Undersökningen är en del av det regionalt-nationelltsamordnade miljöövervakningsprogrammet som startade år 2007. Stationerna ingick mellan 1981 och 2006 i den nationella miljöövervakningen. Fyra av dem har besökts varje år sedan 1970-talet inom tidigare forskningsprojekt, och långtidsförändringar för dessa redovisas separat.

    Huvudfokus för undersökningen är statusbedömning av bottensamhället med hjälp av Benthic Quality Index (BQI). Statusen för Asköområdet har minskat signifikant sedan 1970-talet. Denna minskning beror huvudsakligen på ett skifte från ett bottensamhälle dominerat av vitmärlorna Monoporeia affinis och Pontoporeia femorata till ett dominerat av östersjömusslan Macoma balthica. Sedan mitten av 2000-talet förekommer nu också ett för Östersjön nytt släkte av havsbortmaskar Marenzelleria spp. Både östersjömusslan och den introducerade havsbortsmasken Marenzelleria spp. är tåligare mot låga syrehalter än vitmärlorna och har lägrekänslighetsvärden i BQI-indexet. Detta ger området en lägre status än vid mätningarna under 1970- och början av 1980-talet.

    År 2011 beräknades BQI-värdet (20:e percentilen) för området till 5,8, en försämring sedan 2010 (20:e percentilen av BQI=6,8). Vid en jämförelse över längre tid har områdets BQI-värdenminskat. Den nedåtgående trenden förefaller emellertid ha brutits och från 2001 kan ensignifikant ökning av BQI observeras. Den biologiska mångfalden, uttryckt som antal taxa, följer samma mönster som BQI, med enuppgång sedan 2001. En del av förklaringen till den ökade biologiska mångfalden beror påförekomsten av havsborstmasken Marenzelleria spp. Uppmätta värden av bottenfaunans biomassa ligger nu på ungefär samma nivå som på 1980-talet, efter att under perioden 1996 till2006 ha legat på en högre nivå.

    Sammanfattningsvis visar 2011 års undersökning att miljötillståndet för Asköområdets mjukabottnar förbättrats sedan programmets början 2007, och att den ekologiska statusen har ökat signifikant sedan 2001.

  • 40.
    Svensson, Ola
    et al.
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Sanderson Bellamy, Angelina
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    van den Brink, Paul
    Wageningen University, Department of Aquatic Ecology and Water Quality Management.
    Gunnarsson, Jonas
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Tedengren, Michael
    Stockholm University, Faculty of Science, Department of Systems Ecology.
    Assessing the ecological impact of banana farms on water quality using aquatic macroinvertebrate community compositionIn: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026Article in journal (Refereed)
    Abstract [en]

    In Costa Rica considerable effort goes to conservation and protection of biodiversity while at the same time agricultural pesticide use is among the highest in the world. Several protected areas, some being wetlands or marine reserves, are situated downstream agricultural areas where large-scale banana farms constitute a major land use, with an average of 57 pesticide applications per year. The banana industry is increasingly aware of the need to reduce their negative environmental impact, but few ecological field studies have been made to evaluate the efficiency of proposed mitigation strategies. This study evaluated if benthic macroinvertebrate community structure is sensitive enough to detect environmental impact of banana farming, and thereby usable to measure improvements in pesticide management practices. Aquatic invertebrate samples were collected at 13 sites between March and April 2007, using kick-net sampling. Samples were taken both up- and downstream banana farms in fast flowing streams, with mostly cobbles for substrate in runs and riffles. The changes in community composition were measured at the family level using ordination methods. Additionally, the Biological Monitoring Working Party (BMWP) score system was applied along with a number of community composition descriptors. In total, 2890 specimens were collected, belonging to 14 orders and 49 families or taxa. The results support the hypothesis that surface waters immediately up- and downstream large-scale banana farms have different macroinvertebrate community compositions, with fewer sensitive taxa according to the BMWP-score values at the downstream sites. Rapid assessment using macroinvertebrate community composition thus appears to be a possible means to detect negative impact from chemical-intense agriculture. As the method is moderately time-consuming, low-cost and highly ecologically relevant it could become a useful complement to chemical analysis of pesticide residues in environmental risk assessment.

  • 41.
    Svensson, Ola
    et al.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Sanderson Bellamy, Angelina
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Cardiff University, UK.
    Van den Brink, Paul J.
    Tedengren, Michael
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Assessing the ecological impact of banana farms on water quality using aquatic macroinvertebrate community composition2018In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 25, no 14, p. 13373-13381Article in journal (Refereed)
    Abstract [en]

    In Costa Rica, considerable effort goes to conservation and protection of biodiversity, while at the same time agricultural pesticide use is among the highest in the world. Several protected areas, some being wetlands or marine reserves, are situated downstream large-scale banana farms, with an average of 57 pesticide applications per year. The banana industry is increasingly aware of the need to reduce their negative environmental impact, but few ecological field studies have been made to evaluate the efficiency of proposed mitigation strategies. This study compared the composition of benthic macroinvertebrate communities up- and downstream effluent water from banana farms in order to assess whether benthic invertebrate community structure can be used to detect environmental impact of banana fanning, and thereby usable to assess improvements in management practises. Aquatic invertebrate samples were collected at 13 sites, using kick-net sampling. both up- and downstream banana farms in fast flowing streams in the Caribbean zone of Costa Rica. In total, 2888 invertebrate specimens were collected, belonging to 15 orders and 48 families or taxa. The change in community composition was analysed using multivariate statistics. Additionally, a biodiversity index and the Biological Monitoring Working Party (BMWP) score system was applied along with a number of community composition descriptors. Multivariate analyses indicated that surface waters immediately up- and downstream large-scale banana farms have different macroinvertebrate community compositions with the most evident differences being higher dominance by a single taxa and a much higher total abundance, mostly of that same taxon. Assessment of macroinvertebrate community composition thus appears to be a viable approach to detect negative impact from chemical-intensive agriculture and could become an effective means to monitor the efficacy of changes/proposed improvements in fanning practises in Costa Rica and similar systems.

  • 42. Syberg, Kristian
    et al.
    Backhaus, Thomas
    Banta, Gary
    Bruce, Peter
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Gustavsson, Mikael
    Munns, Wayne R.
    Rämö, Robert
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Selck, Henriette
    Gunnarsson, Jonas S.
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Toward a Conceptual Approach for Assessing Risks from Chemical Mixtures and Other Stressors to Coastal Ecosystem Services2017In: Integrated Environmental Assessment and Management, ISSN 1551-3777, E-ISSN 1551-3793, Vol. 13, no 2, p. 376-386Article in journal (Refereed)
    Abstract [en]

    Growth of human populations and increased human activity, particularly in coastal areas, increase pressure on coastal ecosystems and the ecosystem services (ES) they provide. As a means toward being able to assess the impact of multiple stressors on ES, in the present study we propose an 8-step conceptual approach for assessing effects of chemical mixtures and other stressors on ES in coastal areas: step A, identify the relevant problems and policy aims; step B, identify temporal and spatial boundaries; step C, identify relevant ES; step D, identify relevant stressors (e.g., chemicals); step E, translate impacts into ES units; step F, assess cumulative risk in ES units; step G, rank stressors based on their contribution to adverse effects on ES; and step H, implement regulation and management as appropriate and necessary. Two illustrative case studies (Swedish coastal waters and a coastal lagoon in Costa Rica) are provided; one focuses on chemicals that affect human food supply and the other addresses pesticide runoff and trade-offs among ES. The 2 cases are used to highlight challenges of such risk assessments, including use of standardized versus ES-relevant test species, data completeness, and trade-offs among ES. Lessons learned from the 2 case studies are discussed in relation to environmental risk assessment and management of chemical mixtures. Integr Environ Assess Manag 2017;13:376-386.

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