Browsing NIVA Open Access Archive by Author "Hessen, Dag Olav"
Now showing items 1-20 of 20
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A single pulse of diffuse contaminants alters the size distribution of natural phytoplankton communities
Baho, Didier Ludovic; Pomati, Francesco; Leu, Eva; Hessen, Dag Olav; Moe, S. Jannicke; Norberg, Jon; Nizzetto, Luca (Journal article; Peer reviewed, 2019)The presence of a multitude of bioactive organic pollutants collectively classified as pharmaceuticals and personal care products (PPCPs) in freshwaters is of concern, considering that ecological assessments of their ... -
Climate change vulnerability of Arctic char across Scandinavia
Muhlfeld, Clint C.; Cline, Timothy J.; Finstad, Anders Gravbrøt; Hessen, Dag Olav; Perrin, Sam; Thaulow, Jens; Whited, Diane; Vøllestad, Leif Asbjørn (Peer reviewed; Journal article, 2024)Climate change is anticipated to cause species to shift their ranges upward and poleward, yet space for tracking suitable habitat conditions may be limited for range-restricted species at the highest elevations and latitudes ... -
Congruence, but no cascade - Pelagic biodiversity across three trophic levels in Nordic lakes
Andersen, Tom; Hessen, Dag Olav; Håll, Johnny Peter; Khomich, Maryia; Kyle, Marcia; Lindholm, Markus; Rasconi, Serena; Skjelbred, Birger; Thrane, Jan-Erik; Walseng, Bjørn (Peer reviewed; Journal article, 2020)Covariation in species richness and community structure across taxonomical groups (cross‐taxon congruence) has practical consequences for the identification of biodiversity surrogates and proxies, as well as theoretical ... -
Declining calcium concentration drives shifts toward smaller and less nutritious zooplankton in northern lakes
Bergström, Ann-Kristin; Creed, Irena F.; Paltsev, Aleksey; de Wit, Heleen; Lau, Danny C. P.; Drakare, Stina; Vrede, Tobias; Isles, Peter D. F.; Jonsson, Anders; Geibrink, Erik; Kortelainen, Pirkko; Vuorenmaa, Jussi; Vuorio, Kristiina; Kahilainen, Kimmo Kalevi; Hessen, Dag Olav (Peer reviewed; Journal article, 2024)Zooplankton community composition of northern lakes is changing due to the interactive effects of climate change and recovery from acidification, yet limited data are available to assess these changes combined. Here, we ... -
Do DOM quality and origin affect the uptake and accumulation of a lipid-soluble contaminant in a filter feeding ascidian species (Ciona) that can target small particle size classes?
Schultze, Sabrina; Langva, Hilde K.; Wei, Jing; Chatzigeorgiou, Marios; Rundberget, Thomas; Hessen, Dag Olav; Ruus, Anders; Andersen, Tom; Borgå, Katrine (Peer reviewed; Journal article, 2024)The widely reported increase of terrestrial dissolved organic matter (terrDOM) in northern latitude coastal areas (“coastal darkening”) can impact contaminant dynamics in affected systems. One potential impact is based on ... -
Do DOM quality and origin affect the uptake and accumulation of lipid-soluble contaminants in coastal filter feeders? An experimental simulation of teflubenzuron exposure to blue mussels
Schultze, Sabrina; Andersen, Tom; Knudtzon, Nina Cathrine; Ruus, Anders; Rundberget, Jan Thomas; Brooks, Steven; Poste, Amanda Elizabeth; Hessen, Dag Olav; Borgå, Katrine (Peer reviewed; Journal article, 2023)The increased export of terrestrial dissolved organic matter (terrDOM) to coastal marine ecosystems may affect local filter feeders and the local food web via the altered uptake of organic material and associated contaminants. ... -
Ecological Memory of Historical Contamination Influences the Response of Phytoplankton Communities
Baho, Didier Ludovic; Rizzuto, Simone; Nizzetto, Luca; Hessen, Dag Olav; Norberg, Jon; Skjelbred, Birger; Jones, Kevin C.; Zhang, Hao; Leu, Eva (Peer reviewed; Journal article, 2021)Ecological memory (EM) recognizes the importance of previous stress encounters in promoting community tolerance and thereby enhances ecosystem stability, provided that gained tolerances are preserved during non-stress ... -
Effects of water browning on freshwater biodiversity: the case of the predatory phantom midge Chaoborus nyblaei
Lindholm, Markus; Eie, Martin; Hessen, Dag Olav; Johansen, Joachim Tørum; Weiby, Kristoffer; Thaulow, Jens (Journal article; Peer reviewed, 2018)Water browning, due to increased runoff of terrestrial dissolved organic carbon (DOC), has recently gained considerable attention. While it is well settled how browning affects light regime and thereby aquatic primary ... -
From greening to browning: Catchment vegetation development and reduced S-deposition promote organic carbon load on decadal time scales in Nordic lakes
Finstad, Anders Gravbrøt; Andersen, Tom; Larsen, Søren; Tominaga, Koji; Blumentrath, Stefan; de Wit, Heleen; Tømmervik, Hans; Hessen, Dag Olav (Journal article; Peer reviewed, 2016)Increased concentrations of dissolved organic carbon (DOC), often labelled “browning”, is a current trend in northern, particularly boreal, freshwaters. The browning has been attributed to the recent reduction in sulphate ... -
Functional biogeography: Stoichiometry and thresholds for interpreting nutrient limitation in aquatic plants
Moe, Therese Fosholt; Hessen, Dag Olav; Demars, Benoît Olivier Laurent (Journal article; Peer reviewed, 2019)Atmospheric N pollution may shift nutrient limitations in aquatic autotrophs from N to P or cause an intensification of P limitation in formerly pristine areas. Small changes in nutrient supply in oligotrophic lakes and ... -
Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes
Skau, Lars Fredrik; Andersen, Tom; Thrane, Jan-Erik; Hessen, Dag Olav (Journal article; Peer reviewed, 2017)Temperature and nutrients are key factors affecting the growth, cell size, and physiology of marine phytoplankton. In the ocean, temperature and nutrient availability often covary because temperature drives vertical ... -
Implications of Coastal Darkening for Contaminant Transport, Bioavailability, and Trophic Transfer in Northern Coastal Waters
McGovern, Maeve; Evenset, Anita; Borgå, Katrine; Wit, Heleen de; Braaten, Hans Fredrik Veiteberg; Hessen, Dag Olav; Schultze, Sabrina; Ruus, Anders; Poste, Amanda (Journal article; Peer reviewed, 2019)The increased transport of terrestrially derived organic material (tOM) from catchments to rivers and lakes is leading to browning of northern freshwaters.(1) Although the same environmental drivers can be expected to lead ... -
Juncus bulbosus nuisance growth in oligotrophic freshwater ecosystems: Different triggers for the same phenomenon in rivers and lakes?
Schneider, Susanne Claudia; Moe, Therese Fosholt; Hessen, Dag Olav; Kaste, Øyvind (Journal article; Peer reviewed, 2013)Since the 1980s nuisance growth of the aquatic macrophyte Juncus bulbosus has been observed in an increasing number of rivers and lakes in Europe. Freshwater acidification, lake liming, as well as the impact of hydropower ... -
Land-cover, climate and fjord morphology drive differences in organic matter and nutrient dynamics in two contrasting northern river-fjord systems
Schultze, Sabrina; Andersen, Tom; Hessen, Dag Olav; Ruus, Anders; Borgå, Katrine; Poste, Amanda (Peer reviewed; Journal article, 2022)Climate and land-use changes are leading to impacts on individual ecosystems as well as shifts in transfer dynamics between interconnected systems. At the land-ocean interface, changes in riverine inputs of organic matter ... -
Modelling ROS formation in boreal lakes from interactions between dissolved organic matter and absorbed solar photon flux
Wolf, Raoul; Thrane, Jan-Erik; Hessen, Dag Olav; Andersen, Tom (Journal article; Peer reviewed, 2018)Concentrations of dissolved organic matter (DOM) are increasing in a large number of lakes across the Northern hemisphere. This browning serves a dual role for biota by protecting against harmful ultraviolet radiation, ... -
Nuisance growth of Juncus bulbosus: the roles of genetics and environmental drivers tested in a large-scale survey
Moe, Therese Fosholt; Brysting, Anne Krag; Andersen, Tom; Schneider, Susanne Claudia; Kaste, Øyvind; Hessen, Dag Olav (Journal article; Peer reviewed, 2013)1. Invasive species can transform aquatic ecosystems, and the nuisance growth of the freshwater macrophyte Juncus bulbosus has become a problem in many lakes and rivers in northern Europe. It affects biodiversity strongly ... -
Resilience of Natural Phytoplankton Communities to Pulse Disturbances from Micropollutant Exposure and Vertical Mixing
Baho, Didier Ludovic; Leu, Eva; Pomati, Francesco; Hessen, Dag Olav; Nordberg, Jon; Moe, S. Jannicke; Skjelbred, Birger; Nizzetto, Luca (Journal article; Peer reviewed, 2019)Freshwaters are increasingly exposed to complex mixtures of pharmaceutical and personal care products (PPCPs) from municipal wastewater, which are known to alter freshwater communities’ structure and functioning. However, ... -
Seasonal variation in marine C:N:P stoichiometry: can the composition of seston explain stable Redfield ratios?
Frigstad, Helene; Andersen, Tom; Hessen, Dag Olav; Naustvoll, L..J.; Johnsen, Torbjørn Martin; Bellerby, Richard (Journal article; Peer reviewed, 2011)Seston is suspended particulate organic matter, comprising a mixture of autotrophic, heterotrophic and detrital material. Despite variable proportions of these components, marine seston often exhibits relatively small ... -
Water browning controls adaptation and associated trade-offs in phytoplankton stressed by chemical pollution
Rizzuto, Simone; Thrane, Jan-Erik; Baho, Didier Ludovic; Jones, Kevin C.; Zhang, Hao; Hessen, Dag Olav; Nizzetto, Luca; Leu, Eva Susanne (Peer reviewed; Journal article, 2020)The acquisition of tolerance to an environmental stressor can result in organisms displaying slower growth after stress release. While well-grounded in the theory, empirical evidence of the trade-off between stress tolerance ... -
Widespread diminishing anthropogenic effects on calcium in freshwaters
Weyhenmeyer, Gesa A; Hartmann, Jens; Hessen, Dag Olav; Kopáček, Jiří; Hejzlar, Josef; Jacquet, Stéphan; Hamilton, Stephen K.; Verburg, Piet; Leach, Taylor H.; Schmid, Martin; Flaim, Giovanna; Nõges, Tiina; Nõges, Peeter; Wentzky, Valerie C.; Rogora, Michela; Rusak, James A.; Kosten, Sarian; Paterson, Andrew M.; Teubner, Katrin; Higgins, Scott N.; Lawrence, Gregory; Kangur, Külli; Kokorite, Ilga; Cerasino, Leonardo; Funk, Clara; Harvey, Rebecca; Moatar, Florentina; de Wit, Heleen; Zechmeister, Thomas (Journal article; Peer reviewed, 2019)Calcium (Ca) is an essential element for almost all living organisms. Here, we examined global variation and controls of freshwater Ca concentrations, using 440 599 water samples from 43 184 inland water sites in 57 ...