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13. Vandløb 2012:NOVANA

Author

Wiberg-Larsen, Peter, Windolf, Jørgen, Bøgestrand, Jens, Baattrup-Pedersen, Annette, Kristensen, Esben Astrup, Larsen, Søren Erik, Thodsen, Hans, Ovesen, Niels Bering, Hansen, Rikke Bjerring, Kronvang, Brian, and Kjeldgaard, Ane

Published
2013

16. The legacy of pesticide pollution:an overlooked factor in current risk assessments of freshwater systems

Author

Rasmussen, Jes, Wiberg-Larsen, Peter, Baattrup-Pedersen, Annette, Cedergreen, Nina, McKnight, Ursula S., Kreuger, Jenny, Jacobsen, Dean, Astrup Kristensen, Esben, Friberg, Nikolai, Rasmussen, Jes, Wiberg-Larsen, Peter, Baattrup-Pedersen, Annette, Cedergreen, Nina, McKnight, Ursula S., Kreuger, Jenny, Jacobsen, Dean, Astrup Kristensen, Esben, and Friberg, Nikolai

Abstract

We revealed a history of legacy pesticides in water and sediment samples from 19 small streams across an agricultural landscape. Dominant legacy compounds included organochlorine pesticides, such as DDT and lindane, the organophosphate chlorpyrifos and triazine herbicides such as terbutylazine and simazine which have long been banned in the EU. The highest concentrations of legacy pesticides were found in streams draining catchments with a large proportion of arable farmland suggesting that they originated from past agricultural applications. The sum of toxic units (SumTUD.magna) based on storm water samples from agriculturally impacted streams was significantly higher when legacy pesticides were included compared to when they were omitted. Legacy pesticides did not significantly change the predicted toxicity of water samples to algae or fish. However, pesticide concentrations in bed sediment and suspended sediment samples exceeded safety thresholds in 50% of the samples and the average contribution of legacy pesticides to the SumTUC.riparius was >90%. Our results suggest that legacy pesticides can be highly significant contributors to the current toxic exposure of stream biota, especially macroinvertebrate communities, and that those communities were primarily exposed to legacy pesticides via the sediment. Additionally, our results suggest that neglecting legacy pesticides in the risk assessment of pesticides in streams may severely underestimate the risk of ecological effects.

Published
2015

17. The legacy of pesticide pollution: An overlooked factor in current risk assessments of freshwater systems

Author

Rasmussen, Jes Jessen, Wiberg-Larsen, Peter, Baattrup-Pedersen, Annette, Cedergreen, Nina, McKnight, Ursula S., Kreuger, Jenny, Jacobsen, Dean, Kristensen, Esben A., Friberg, Nikolai, Rasmussen, Jes Jessen, Wiberg-Larsen, Peter, Baattrup-Pedersen, Annette, Cedergreen, Nina, McKnight, Ursula S., Kreuger, Jenny, Jacobsen, Dean, Kristensen, Esben A., and Friberg, Nikolai

Abstract

We revealed a history of legacy pesticides in water and sediment samples from 19 small streams across an agricultural landscape. Dominant legacy compounds included organochlorine pesticides, such as DDT and lindane, the organophosphate chlorpyrifos and triazine herbicides such as terbutylazine and simazine which have long been banned in the EU. The highest concentrations of legacy pesticides were found in streams draining catchments with a large proportion of arable farmland suggesting that they originated from past agricultural applications. The sum of toxic units (SumTUD.magna) based on storm water samples from agriculturally impacted streams was significantly higher when legacy pesticides were included compared to when they were omitted. Legacy pesticides did not significantly change the predicted toxicity of water samples to algae or fish. However, pesticide concentrations in bed sediment and suspended sediment samples exceeded safety thresholds in 50% of the samples and the average contribution of legacy pesticides to the SumTUC.riparius was >90%. Our results suggest that legacy pesticides can be highly significant contributors to the current toxic exposure of stream biota, especially macroinvertebrate communities, and that those communities were primarily exposed to legacy pesticides via the sediment. Additionally, our results suggest that neglecting legacy pesticides in the risk assessment of pesticides in streams may severely underestimate the risk of ecological effects.

Published
2015

21. Fiskeundersøgelser i vandløb

Author

Wiberg-Larsen, Peter and Kristensen, Esben Astrup

Subjects
Vandløb, Teknisk anvisning, Fisk, NOVANA
Published
2011

24. Danmarks biodiversitet 2010:Status, udvikling og trusler

Author

Wiberg-Larsen, Peter, Holm, Thomas Eske, Josefson, Alf B., Strandberg, Beate, Nygaard, Bettina, Andersen, Liselotte Wesley, Winding, Anne, Termansen, Mette, D.D. Hansen, Morten, Søndergaard, Martin, Lundsteen, Steffen, Baattrup-Pedersen, Annette, Kristensen, Esben Astrup, Krogh, Paul Henning, Simonsen, Vibeke, Hasler, Berit, Levin, Gregor, Asferg, Tommy, Ejrnæs, Rasmus, and Hansen, Anja Skjoldborg

Abstract

Vi undersøger i denne rapport, om Danmark har nået EU’s mål om at standse tabet af biodiversitet ved udgangen af 2010. Undersøgelsen gennemføres for skov, kyst, græsland/hede, mose/eng, søer, vandløb, hav, agerland og det urbane landskab. For hvert af disse ni økosystemer er udvalgt mellem 10 og 20 elementer, som tilsammen repræsenterer de truede arter, levesteder og processer i økosystemet. I alt vurderes udviklingen af 139 elementer af biodiversitet, hvoraf 47 % er i tilbagegang, 25 % er stabile eller i fremgang og 28 % har ukendt udvikling. For hvert økosystem fremlægges baggrunden for udviklingen i form af en status for biodiversiteten og en gennemgang af truslerne. Genetisk og mikrobiologisk diversitet er vigtige for den samlede biodiversitet, men det er endnu ikke muligt at vurdere udviklingen. Biodiversitet har stor værdi for samfundet, men en gennemgang af de eksisterende studier viser, at værdien afhænger af hvordan man spørger. Rapporten viser, at der er behov for målrettet handling og bedre viden, hvis tabet af biodiversitet skal standses.

Published
2011

26. Vandløb 2009:NOVANA

Author

Wiberg-Larsen, Peter, Windolf, Jørgen, Baattrup-Pedersen, Annette, Bøgestrand, Jens, Ovesen, Niels Bering, Larsen, Søren Erik, Thodsen, Hans, Sode, Annette, Kristensen, Esben Astrup, and Kjeldgaard, Ane

Published
2010

27. Fiskeundersøgelser i danske vandløb

Author

Kristensen, Esben and Wiberg-Larsen, Peter

Subjects
vand, water
Abstract

Siden 1998 er der indsamlet fiskedata fra danske vandløb som et led i en national miljøovervågning. Undersøgelserne er relativt resursekrævende. Derfor er det vigtigt, at de bidrager med brugbare resultater - ikke mindst for at kunne medvirke til at opfylde intentionerne i EU's Vandrammedirektiv. Er det ikke tilfældet, må metoder og omfang naturligvis justeres. Denne artikel fokuserer på problemstillingen ud fra et relativt stort sæt af data fra det nationale overvågningsprogram.

Published
2008

30. Identifikation af referencevandløb til implementering af vandrammedirektivet i Danmark

Author

Kristensen, Esben Astrup, Baattrup-Pedersen, Annette, Skriver, Jens, Jørgensen, Joan, Kronvang, Brian, Andersen, Hans Estrup, Hoffmann, Carl Christian, and Wiberg-Larsen, Peter

Subjects
makrofyter, vand, referencetilstand, fisk, water, vandløb, vandrammedirektiv, makroinvertebrater
Abstract

Definition og beskrivelse af referencetilstanden er centralt for implementering af vandrammedirektivet, da bedømmelse af den økologiske tilstand sker som afvigelsen fra den upåvirkede referencetilstand. I denne rapport præsenteres analyser af danske, udenlandske og historiske data med det formål at definere og beskrive referencetilstanden for fisk, makroinvertebrater og makrofyter i vandløb. Med udgangspunkt i NOVANA-data er der foretaget en screening af danske vandløb for referencestatus. Fysiske, kemiske, hydromorfologiske og påvirkningsmæssige kriterier fastsat ud fra REFCOND-anbefalinger blev anvendt i en screening af 128 a priori-udvalgte referencevandløb. Kun 3 af disse opfylder de lempede referencekrav og kan betegnes som værende i lempet referencetilstand. Den væsentligste årsag til manglende opfyldelse af kravene er andelen af landbrug og befæstet areal i oplandet. En screening af samtlige danske vandløb blev derfor foretaget med disse 2 kriterier, men kun få og fortrinsvist meget små vandløb opfylder kriterierne. Det kan derfor konkluderes, at der inden for Danmarks grænser ikke findes tilstrækkeligt med referencevandløb til, at den naturlige variation i de biologiske kvalitetselementer kan beskrives. En analyse og sammenligning af makrofytsamfund i Danmark og Baltikum samt efterfølgende validering med historiske data fra danske vandløb viste stor lighed mellem nutidige plantesamfund i Baltikum og historiske samfund i Danmark. Det er derfor muligt at bruge Baltiske vandløb som referencer for danske vandløb mht. makrofyter. Der kræves yderligere undersøgelser, før det kan afgøres om vandløb i Baltikum kan fungere som referencer for danske vandløb mht. fisk og makroinvertebrater. Rapporten indeholder anbefalinger til fremtidigt arbejde med beskrivelse af referencetilstanden.

Published
2008

31. Environmental and spatial controls of taxonomic versus trait composition of stream biota.

Author

Göthe, Emma, Baattrup‐Pedersen, Annette, Wiberg‐Larsen, Peter, Graeber, Daniel, Kristensen, Esben A., and Friberg, Nikolai

Subjects
INVERTEBRATES, MACROPHYTES, BIOTIC communities, FRESHWATER ecology, ECOSYSTEMS
Abstract

The spatial organisation of biotic communities derives from factors operating at a wide range of spatial and temporal scales. Despite strong scientific evidence of prevalent spatial control of community composition in freshwater ecosystems, local environmental factors are often considered as the main drivers of community change. Furthermore, taxonomic approaches are most frequently used, and few studies have compared the relative importance of local and regional control of trait versus the taxonomic composition in stream ecosystems., Using a spatially dense data set covering all stream sizes in a lowland European region of c. 42 000 km2 and three organism groups (macrophytes, macroinvertebrates and fishes), we compared the relative importance of spatial and environmental determinants of species and trait composition in the study streams, classified into headwaters (stream order 1-2) and downstream sites (stream order >2)., We hypothesised that (i) there is a higher correspondence between environmental conditions and trait composition than with species composition, (ii) dispersal limitation (pure spatial structuring) is greater in headwaters than in downstream sites and (iii) dispersal limitation (pure spatial structuring) is weakest for macroinvertebrates, intermediate for macrophytes and strongest for fishes., The most consistent pattern across organisms and stream order groups was a higher correspondence between environmental variation and trait composition as well as a higher number of environmental variables significantly related to trait composition than with species composition (hypothesis 1). Spatial structuring peaked in headwater macrophyte communities and downstream fish communities (hypotheses 2 & 3) - a pattern that was amplified when separate analyses of traits describing species dispersal potential were undertaken., Our study highlights the potential of traits to capture multiple environmental changes in stream ecosystems and illustrates how organism-specific and highly context-dependent patterns in community organisation can emerge as a consequence of interactions between habitat connectivity (i.e. top versus lower parts of the stream network) and organism dispersal potential. [ABSTRACT FROM AUTHOR]

Published
2017
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32. Pyrethroid effects on freshwater invertebrates: A meta-analysis of pulse exposures

Author

Rasmussen, Jes Jessen, Wiberg-Larsen, Peter, Kristensen, Esben Astrup, Cedergreen, Nina, Friberg, Nikolai, Rasmussen, Jes Jessen, Wiberg-Larsen, Peter, Kristensen, Esben Astrup, Cedergreen, Nina, and Friberg, Nikolai

Abstract

Pyrethroids are widely used insecticides that may seriously harm aquatic organisms. Being strongly hydrophobic, pyrethroids in solution occur only in short pulses but may be retained in sediments for longer periods. Consequently, most studies consider the chronic exposure of sediment dwelling organisms. We collected data from 16 studies to determine effect thresholds for stream macro-invertebrates exposed to short pyrethroid pulses evaluating lethal and sublethal ecologically relevant endpoints. Dose-response models showed EC50 for lethality, functional and behavioural endpoints down to 1/100,1/100 and 1/1000 of the 48 h LC50 for Daphnia magna, respectively. The results indicate that the overall sensitivity of stream macroinvertebrates to pyrethroids may be higher than previously believed. This review shows the relevance of incorporating data on sublethal endpoints and appropriate post-exposure observation periods in future studies. The current risk assessment procedures and the higher tier approach are discussed in the light of our results. (C) 2013 Elsevier Ltd. All rights reserved.

Published
2013

33. Monitoring fish communities in wadeable lowland streams: comparing the efficiency of electrofishing methods at contrasting fish assemblages

Author

Teixeira-de Mello, Franco, primary, Kristensen, Esben A., additional, Meerhoff, Mariana, additional, González-Bergonzoni, Iván, additional, Baattrup-Pedersen, Annette, additional, Iglesias, Carlos, additional, Kristensen, Peter B., additional, Mazzeo, Néstor, additional, and Jeppesen, Erik, additional

Published
2013
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43. Determining the spatial distribution of spawning by anadromous and resident brown trout Salmo trutta L using strontium content of eggs collected from redds.

Author

Kristensen, Esben A., Closs, Gerard P., Olley, Ricky, Kim, Jonathan, Reid, Malcolm, and Stirling, Claudine

Subjects
*SPATIAL behavior in animals, *FISH spawning, *BROWN trout, *STRONTIUM, *FISH eggs, *FISH nests, *FISH migration
Abstract

- Strontium (Sr) content of eggs collected from redds were used to determine the spawning contribution of resident and anadromous female brown trout in the Taieri River, New Zealand and were analysed on the catchment and tributary scale. At the catchment scale, analysis of Sr showed differences between eggs collected above and below the Taieri River Gorge. Samples collected above the gorge all had low-Sr concentrations similar to levels found in an entirely resident brown trout population. Samples collected below the gorge exhibited a broad range in Sr concentrations, ranging from levels comparable to the known anadromous samples to levels comparable to the known freshwater-resident samples. This suggests that the gorge prevents upstream migration by anadromous brown trout in the Taieri River. At the tributary scale, this pattern of anadromous brown trout spawning downstream of freshwater-resident fish was repeated in one of the two tributaries located downstream of the gorge. Energetic cost of migration is the most likely explanation for the observed patterns in catchment and tributary scale distribution of spawning by resident and anadromous brown trout. It is concluded that the use of Sr concentrations in eggs collected from redds is a cost-effective and reliable method to investigate the spawning contribution by anadromous brown trout. [ABSTRACT FROM AUTHOR]

Published
2011
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