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  • 1.
    Dietrich, Anna
    et al.
    Umeå University, Sweden.
    Lind, Lovisa
    Umeå University, Sweden.
    Nilsson, Christer
    Umeå University, Sweden.
    Jansson, Roland
    Umeå University, Sweden.
    The Use of Phytometers for Evaluating Restoration Effects on Riparian Soil Fertility2014In: Journal of Environmental Quality, ISSN 0047-2425, E-ISSN 1537-2537, Vol. 43, no 6, p. 1916-1925Article in journal (Refereed)
    Abstract [en]

    The ecological restoration of streams in Sweden has become increasingly important to counteract effects of past timber floating. In this study, we focused on the effect on riparian soil properties after returning coarse sediment (cobbles and boulders) to the channel and reconnecting riparian with instream habitats. Restoration increases habitat availability for riparian plants, but its effects on soil quality are unknown. We also analyzed whether the restoration effect differs with variation in climate and stream size. We used standardized plant species to measure the performance of a grass (Phleum pratense L.) and a forb (Centaurea cyanus L.) in soils sampled in the riparian zones of channelized and restored streams and rivers. Furthermore, we analyzed the mass fractions of carbon (C) and nitrogen (N) along with the proportions of the stable isotopes C-13 and N-15 in the soil, as well as its grain size composition. We found a positive effect of restoration on biomass of phytometers grown in riparian soils from small streams, indicating that restoration enhanced the soil properties favoring plant performance. We suggest that changed flooding with more frequent but less severe floods and slower flows, enhancing retention, could explain the observed patterns. This positive effect suggests that it may be advantageous to initiate restoration efforts in small streams, which make up the highest proportion of the stream network in a catchment. Restoration responses in headwater streams may then be transmitted downstream to facilitate recovery of restored larger rivers. If the larger rivers were restored first, a slower reaction would be expected.

  • 2.
    Hintz, William D.
    et al.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, 110 8th St, Rensselaer, NY 12180 USA..
    Mattes, Brian M.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, 110 8th St, Rensselaer, NY 12180 USA..
    Schuler, Matthew S.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, 110 8th St, Rensselaer, NY 12180 USA..
    Jones, Devin K.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, 110 8th St, Rensselaer, NY 12180 USA..
    Stoler, Aaron B.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, 110 8th St, Rensselaer, NY 12180 USA..
    Lind, Lovisa
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, 110 8th St, Rensselaer, NY 12180 USA..
    Relyea, Rick A.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, 110 8th St, Rensselaer, NY 12180 USA..
    Salinization triggers a trophic cascade in experimental freshwater communities with varying food-chain length2017In: Ecological Applications, ISSN 1051-0761, E-ISSN 1939-5582, Vol. 27, no 3, p. 833-844Article in journal (Refereed)
    Abstract [en]

    The application of road deicing salts in northern regions worldwide is changing the chemical environment of freshwater ecosystems. Chloride levels in many lakes, streams, and wetlands exceed the chronic and acute thresholds established by the United States and Canada for the protection of freshwater biota. Few studies have identified the impacts of deicing salts in stream and wetland communities and none have examined impacts in lake communities. We tested how relevant concentrations of road salt (15, 100, 250, 500, and 1000mgCl(-)/L) interacted with experimental communities containing two or three trophic levels (i.e., no fish vs. predatory fish). We hypothesized that road salt and fish would have a negative synergistic effect on zooplankton, which would then induce a trophic cascade. We tested this hypothesis in outdoor mesocosms containing filamentous algae, periphyton, phytoplankton, zooplankton, several macroinvertebrate species, and fish. We found that the presence of fish and high salt had a negative synergistic effect on the zooplankton community, which in turn caused an increase in phytoplankton. Contributing to the magnitude of this trophic cascade was a direct positive effect of high salinity on phytoplankton abundance. Cascading effects were limited with respect to impacts on the benthic food web. Periphyton and snail grazers were unaffected by the salt-induced trophic cascade, but the biomass of filamentous algae decreased as a result of competition with phytoplankton for light or nutrients. We also found direct negative effects of high salinity on the biomass of filamentous algae and amphipods (Hyalella azteca) and the mortality of banded mystery snails (Viviparus georgianus) and fingernail clams (Sphaerium simile). Clam mortality was dependent on the presence of fish, suggesting a non-consumptive interactive effect with salt. Our results indicate that globally increasing concentrations of road salt can alter community structure via both direct and indirect effects.

  • 3.
    Jones, Devin K.
    et al.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Mattes, Brian M.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Hintz, William D.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Schuler, Matthew S.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Stoler, Aaron B.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Lind, Lovisa
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Cooper, Reilly O.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Relyea, Rick A.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Investigation of road salts and biotic stressors on freshwater wetland communities2017In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 221, p. 159-167Article in journal (Refereed)
    Abstract [en]

    The application of road deicing salts has led to the salinization of freshwater ecosystems in northern regions worldwide. Increased chloride concentrations in lakes, streams, ponds, and wetlands may negatively affect freshwater biota, potentially threatening ecosystem services. In an effort to reduce the effects of road salt, operators have increased the use of salt alternatives, yet we lack an understanding of how these deicers affect aquatic communities. We examined the direct and indirect effects of the most commonly used road salt (NaCl) and a proprietary salt mixture (NaCl, KCl, MgCl2), at three environmentally relevant concentrations (150, 470, and 780 mg Cl-/L) on freshwater wetland communities in combination with one of three biotic stressors (control, predator cues, and competitors). The communities contained periphyton, phytoplankton, zooplankton, and two tadpole species (American toads, Anaxyrus americanus; wood frogs, Lithobates sylvaticus). Overall, we found the two road salts did not interact with the natural stressors. Both salts decreased pH and reduced zooplankton abundance. The strong decrease in zooplankton abundance in the highest NaCl concentration caused a trophic cascade that resulted in increased phytoplankton abundance. The highest NaCl concentration also reduced toad activity. For the biotic stressors, predatory stress decreased whereas competitive stress increased the activity of both tadpole species. Wood frog survival, time to metamorphosis, and mass at metamorphosis all decreased under competitive stress whereas toad time to metamorphosis increased and mass at metamorphosis decreased. Road salts and biotic stressors can both affect freshwater communities, but their effects are not interactive. (C) 2016 Elsevier Ltd. All rights reserved.

  • 4.
    Lind, Lovisa
    et al.
    Umeå University, Umeå, Sweden.
    Alfredsen, Knut
    University of Science and Technology, 7491 Trondheim, Norway.
    Kuglerova, Lenka
    University of British Columbia, V6T 1Z4 Vancouver, Canada.
    Nilsson, Christer
    Umeå University, Umeå, Sweden.
    Hydrological and thermal controls of ice formation in 25 boreal stream reaches2016In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 540, p. 797-811Article in journal (Refereed)
    Abstract [en]

    The Northern Hemisphere has a high density of fluvial freshwater ecosystems, many of which become ice-covered during winter. The development and extent of ice have both ecological and socio-economic implications. For example, ice can cause freezing of riparian vegetation and fish eggs as well as influence hydropower production; however, when, where and why ice develops in small streams is not well known. We used observations from 25 stream reaches to study the factors controlling ice development during two consecutive winters, addressing where in the catchment surface or anchor-ice is most likely to develop, how stream morphology influences ice formation, and how climate influences ice processes. Reaches far downstream from lake outlets, or without any upstream lakes, were most prone to develop anchor-ice, but other factors also influenced ice formation. Anchor-ice was most common where water temperature and groundwater inputs were low and stream power high. Given cold air temperature and water supercooling, the in-stream substrate as well as the current velocity were also important for the development of anchor-ice. Climate and substrate seemed to be important factors for the development of surface ice. This study shows that ice processes are substantial during the hydrological year and may therefore have large implications for the ecology and engineering around boreal streams.. The study also demonstrates that ice formation in the studied streams was complex, involving many variables and physical processes. We constructed a conceptual model describing the likelihood for various ice types to develop, based on the large dataset. As such, this model will be useful for practitioners and scientists working in small watercourses in the Northern Hemisphere.

  • 5.
    Lind, Lovisa
    et al.
    Umeå University, Sweden.
    Nilsson, Christer
    Umeå University, Sweden.
    Vegetation patterns in small boreal streams relate to ice and winter floods2015In: Journal of Ecology, ISSN 0022-0477, E-ISSN 1365-2745, Vol. 103, no 2, p. 431-440Article in journal (Refereed)
    Abstract [en]

    In-stream and riparian vegetation are species rich, productive and dynamic. Their patterns insmall boreal streams are largely driven by seasonal flow regimes. Traditionally, flow-related processes during the growing season, particularly the spring flood, have been seen as the most important, whereas vegetation has been viewed as being dormant and ‘less affected’ during winter. Riparian and in-stream vegetation were inventoried during the summers 2011–2013 in eight reaches of northern Swedish streams. Along each reach, the ice formation was surveyed during winter by visual inspections and with permanently placed cameras. We then evaluated the potential effects of ice regimes and winter flooding on riparian and in-stream vegetation during 3 years by relating the abundance of winter floods caused by anchor ice to the cover, composition and biomass of vegetation. We found that the numbers of winter floods were higher along reaches with anchor-ice formation than in reaches without. We also found that species diversity of riparian vegetation was higher inthe reaches with anchor ice. This resulted from a lower cover of riparian dwarf shrubs and a higher cover of graminoids and forbs along reaches with anchor ice. We also found a lower cover of instream algae but a higher cover of bryophytes in anchor-ice reaches. These patterns were consistent throughout the study period although there were interannual differences in temperature, water levels and ice cover. During our study period, we encountered an average of 20 shifts per winter between freezing and thawing, while there was an average of 10 shifts per winter during 1960–1990. This indicates a warming climate in high latitudes. Higher temperatures and more shifts between freezing and thawing may initially increase ice dynamics. However, with further increases in mean temperature, ice production should eventually decrease. Synthesis. Ice and winter floods caused by anchor ice appear to be important disturbance agents that allow less competitive species to establish along small boreal streams. If ice dynamics is reduced, the composition and production of riparian and in-stream vegetation may be changed, with possible consequences for the entire stream ecosystem.

  • 6.
    Lind, Lovisa
    et al.
    Umeå University, Umeå, Sweden.
    Nilsson, Christer
    Umeå University, Umeå, Sweden.
    Polvi, Lina E.
    Umeå University, Umeå, Sweden.
    Weber, Christine
    Umeå University, Umeå, Sweden.
    The role of ice dynamics in shaping vegetation in flowing waters2014In: Biological Reviews, ISSN 1464-7931, E-ISSN 1469-185X, Vol. 89, no 4, p. 791-804Article in journal (Refereed)
    Abstract [en]

    Ice dynamics is an important factor affecting vegetation in high-altitude and high-latitude streams and rivers. During the last few decades, knowledge about ice in streams and rivers has increased significantly and a respectable body of literature is now available. Here we review the literature on how ice dynamics influence riparian and aquatic vegetation. Traditionally, plant ecologists have focused their studies on the summer period, largely ignoring the fact that processes during winter also impact vegetation dynamics. For example, the freeze-up period in early winter may result in extensive formation of underwater ice that can restructure the channel, obstruct flow, and cause flooding and thus formation of more ice. In midwinter, slow-flowing reaches develop a surface-ice cover that accumulates snow, protecting habitats under the ice from formation of underwater ice but also reducing underwater light, thus suppressing photosynthesis. Towards the end of winter, ice breaks up and moves downstream. During this transport, ice floes can jam up and cause floods and major erosion. The magnitudes of the floods and their erosive power mainly depend on the size of the watercourse, also resulting in different degrees of disturbance to the vegetation. Vegetation responds both physically and physiologically to ice dynamics. Physical action involves the erosive force of moving ice and damage caused by ground frost, whereas physiological effects - mostly cell damage - happen as a result of plants freezing into the ice. On a community level, large magnitudes of ice dynamics seem to favour species richness, but can be detrimental for individual plants. Human impacts, such as flow regulation, channelisation, agriculturalisation and water pollution have modified ice dynamics; further changes are expected as a result of current and predicted future climate change. Human impacts and climate change can both favour and disfavour riverine vegetation dynamics. Restoration of streams and rivers may mitigate some effects of anticipated climate change on ice and vegetation dynamics by, for example, slowing down flows and increasing water depth, thus reducing the potential for massive formation of underwater ice.

  • 7.
    Lind, Lovisa
    et al.
    Umeå University, Umeå, Sweden.
    Nilsson, Christer
    Umeå University, Umeå, Sweden.
    Weber, Christine
    Umeå University, Umeå, Sweden.
    Effects of ice and floods on vegetation in streams in cold regions: implications for climate change2014In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 4, no 21, p. 4173-4184Article in journal (Refereed)
    Abstract [en]

    Riparian zones support some of the most dynamic and species-rich plant communities in cold regions. A common conception among plant ecologists is that flooding during the season when plants are dormant generally has little effect on the survival and production of riparian vegetation. We show that winter floods may also be of fundamental importance for the composition of riverine vegetation. We investigated the effects of ice formation on riparian and in-stream vegetation in northern Sweden using a combination of experiments and observations in 25 reaches, spanning a gradient from ice-free to ice-rich reaches. The ice-rich reaches were characterized by high production of frazil and anchor ice. In a couple of experiments, we exposed riparian vegetation to experimentally induced winter flooding, which reduced the dominant dwarf-shrub cover and led to colonization of a species-rich forb-dominated vegetation. In another experiment, natural winter floods caused by anchor-ice formation removed plant mimics both in the in-stream and in the riparian zone, further supporting the result that anchor ice maintains dynamic plant communities. With a warmer winter climate, ice-induced winter floods may first increase in frequency because of more frequent shifts between freezing and thawing during winter, but further warming and shortening of the winter might make them less common than today. If ice-induced winter floods become reduced in number because of a warming climate, an important disturbance agent for riparian and in-stream vegetation will be removed, leading to reduced species richness in streams and rivers in cold regions. Given that such regions are expected to have more plant species in the future because of immigration from the south, the distribution of species richness among habitats can be expected to show novel patterns.

  • 8.
    Lind, Lovisa
    et al.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, Troy, NY 12180 USA.;Umea Univ, Dept Ecol & Environm Sci, S-90187 Umea, Sweden..
    Schuler, Matthew S.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Hintz, William D.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Stoler, Aaron B.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, Troy, NY 12180 USA.;Stockton Univ, Dept Nat Sci & Math, Galloway, NJ 08205 USA..
    Jones, Devin K.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, Troy, NY 12180 USA.;Univ S Florida, Dept Integrat Biol, Tampa, FL 33620 USA..
    Mattes, Brian M.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Relyea, Rick A.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Salty fertile lakes: how salinization and eutrophication alter the structure of freshwater communities2018In: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 9, no 9, article id e02383Article in journal (Refereed)
    Abstract [en]

    The quality of freshwater ecosystems is decreasing worldwide because of anthropogenic activities. For example, nutrient over-enrichment associated with agricultural, urban, and industrial development has led to an acceleration of primary production, or eutrophication. Additionally, in northern areas, deicing salts that are an evolutionary novel stressor to freshwater ecosystems have caused chloride levels of many freshwaters to exceed thresholds established for environmental protection. Even if excess nutrients and road deicing salts often contaminate freshwaters at the same time, the combined effects of eutrophication and salinization on freshwater communities are unknown. Thus by using outdoor mesocosms, we investigated the potentially interactive effects of nutrient additions and road salt (NaCl) on experimental lake communities containing phytoplankton, periphyton, filamentous algae, zooplankton, two snail species (Physa acuta and Viviparus georgianus), and macrophytes (Nitella spp.). We exposed communities to a factorial combination of environmentally relevant concentrations of road salt (15, 250, and 1000 mg Cl-/L), nutrient additions (oligotrophic, eutrophic), and sunlight (low, medium, and high) for 80 d. We manipulated light intensity to parse out the direct effects of road salts or nutrients from the indirect effects via algal blooms that reduce light levels. We observed numerous direct and indirect effects of salt, nutrients, and light as well as interactive effects. Added nutrients caused increases in most producers and consumers. Increased salt (1000 mg Cl-/L) initially caused a decline in cladoceran and copepod abundance, leading to an increase in phytoplankton. Increased salt also reduced the biomass and chl a content of Nitella and reduced the abundance of filamentous algae. Added salt had no effect on the abundance of pond snails, but it caused a decline in banded mystery snails, which led to an increase in periphyton. Low light negatively affected all taxa (except Nitella) and light levels exhibited multiple interactions with road salt, but the combined effects of nutrients and salt were always additive. Collectively, our results indicate that eutrophication and salinization both have major effects on aquatic ecosystems and their combined effects (through different mechanisms) are expected to promote large blooms of phytoplankton and periphyton while causing declines in many species of invertebrates and macrophytes.

  • 9.
    Nilsson, Christer
    et al.
    Umeå University, Umeå, Sweden.
    Polvi, Lina E
    Umeå University, Umeå, Sweden.
    Gardeström, Johanna
    Umeå University, Umeå, Sweden.
    Maher Hasselquist, Eliza
    Umeå University, Umeå, Sweden.
    Lind, Lovisa
    Umeå University, Umeå, Sweden.
    Sarneel, Judith M
    Umeå University, Umeå, Sweden.
    Riparian and in-stream restoration of boreal streams and rivers: success or failure?2015In: Ecohydrology, ISSN 1936-0584, E-ISSN 1936-0592, Vol. 8, no 5, p. 753-764Article in journal (Refereed)
    Abstract [en]

    We reviewed follow-up studies from Finnish and Swedish streams that have been restored after timber floating to assess the abiotic and biotic responses to restoration. More specifically, from a review of 18 case studies (16 published and 2 unpublished), we determined whether different taxonomic groups react differently or require different periods of time to respond to the same type of restoration. Restoration entailed returning coarse sediment (cobbles and boulders) and sometimes large wood to previously channelized turbulent reaches, primarily with the objective of meeting habitat requirements of naturally reproducing salmonid fish. The restored streams showed a consistent increase in channel complexity and retention capacity, but the biotic responses were weak or absent in most species groups. Aquatic mosses growing on boulders were drastically reduced shortly after restoration, but in most studies, they recovered after a few years. Riparian plants, macroinvertebrates and fish did not show any consistent trends in response. We discuss seven alternative explanations to these inconsistent results and conclude that two decades is probably too short a time for most organisms to recover. We recommend long-term monitoring using standardized methods, a landscape-scale perspective and a wider range of organisms to improve the basis for judging to what extent restoration in boreal streams has achieved its goal of reducing the impacts from timber floating.

  • 10.
    Nilsson, Christer
    et al.
    Umeå University, Umeå, Sweden.
    Polvi, Lina E
    Umeå University, Umeå, Sweden.
    Lind, Lovisa
    Umeå University, Umeå, Sweden.
    Extreme events in streams and rivers in arctic and subarctic regions in an uncertain future2015In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 60, no 12, p. 2535-2546Article in journal (Refereed)
    Abstract [en]

    We review the predicted changes in extreme events following climate change in flowing waters in arctic and subarctic regions. These regions are characterised by tundra or taiga ecosystems in either erosional or depositional glacial landforms or presently glacierised areas of the Northern Hemisphere. The ecological and geomorphic effects of extreme meteorological and hydrological events, such as episodes of strongly increased precipitation, temperatures and flows, can be exacerbated by altered base conditions. For example, winter temperature variations between frost and thaw will become more frequent at many places because mean temperature during the winter is closer to 0 °C, potentially leading to changes in the production of ice and intensified disturbance of riparian and aquatic habitats during extreme floods. Additionally, thawing of permafrost and glaciers can lead to increased bank erosion because of thaw slump and glacial outburst floods. We discuss the abiotic and biotic effects of these and other extreme events, including heavy precipitation, floods, drought and extreme air or water temperatures, and summarise our findings in a model that aims to stimulate further research in this field.

  • 11.
    Nilsson, Christer
    et al.
    Umeå University, Umeå, Sweden.
    Sarneel, Judith M.
    Umeå University, Umeå, Sweden; Utrecht UniversityUtrechtThe Netherlands.
    Palm, Daniel
    Umeå University, Umeå, Sweden.
    Gardeström, Johanna
    Umeå University, Umeå, Sweden.
    Pilotto, Francesca
    Umeå University, Umeå, Sweden.
    Polvi, Lina E.
    Umeå University, Umeå, Sweden.
    Lind, Lovisa
    Umeå University, Umeå, Sweden.
    Holmqvist, Daniel
    Utrecht University, Utrecht, The Netherlands.
    Lundqvist, Hans
    Ume/Vindel River Fishery Advisory BoardLyckseleSweden.
    How do biota respond to additional physical restoration of restored streams?2017In: Ecosystems (New York. Print), ISSN 1432-9840, E-ISSN 1435-0629, Vol. 20, no 1, p. 144-162Article in journal (Refereed)
    Abstract [en]

    Restoration of channelized streams by returning coarse sediment from stream edges to the wetted channel has become a common practice in Sweden. Yet, restoration activities do not always result in the return of desired biota. This study evaluated a restoration project in the Vindel River in northern Sweden in which practitioners further increased channel complexity of previously restored stream reaches by placing very large boulders (> 1 m), trees (> 8 m), and salmonid spawning gravel from adjacent upland areas into the channels. One reach restored with basic methods and another with enhanced methods were selected in each of ten different tributaries to the main channel. Geomorphic and hydraulic complexity was enhanced but the chemical composition of riparian soils and the communities of riparian plants and fish did not exhibit any clear responses to the enhanced restoration measures during the first 5 years compared to reaches restored with basic restoration methods. The variation in the collected data was among streams instead of between types of restored reaches. We conclude that restoration is a disturbance in itself, that immigration potential varies across landscapes, and that biotic recovery processes in boreal river systems are slow. We suggest that enhanced restoration has to apply a catchment-scale approach accounting for connectivity and availability of source populations, and that low-intensity monitoring has to be performed over several decades to evaluate restoration outcomes.

  • 12.
    Schuler, Matthew S.
    et al.
    Department of Biology, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, NY, USA.
    Hintz, William D.
    Department of Biology, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, NY, USA.
    Jones, Devin K.
    Department of Biology, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, NY, USA.
    Lind, Lovisa
    Department of Biology, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, NY, USA.
    Mattes, Brian M.
    Department of Biology, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, NY, USA.
    Stoler, Aaron B.
    Department of Biology, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, NY, USA.
    Sudol, Kelsey A.
    Department of Biology, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, NY, USA.
    Relyea, Rick A.
    Department of Biology, Rensselaer Polytechnic Institute, Darrin Fresh Water Institute, Troy, NY, USA.
    How common road salts and organic additives alter freshwater food webs: in search of safer alternatives2017In: Journal of Applied Ecology, ISSN 0021-8901, E-ISSN 1365-2664, Vol. 54, no 5, p. 1353-1361Article in journal (Refereed)
    Abstract [en]

    1. The application of deicing road salts began in the 1940s and has increased drastically in regions where snow and ice removal is critical for transportation safety. The most commonly applied road salt is sodium chloride (NaCl). However, the increased costs of NaCl, its negative effects on human health, and the degradation of roadside habitats has driven transportation agencies to seek alternative road salts and organic additives to reduce the application rate of NaCl or increase its effectiveness. Few studies have examined the effects of NaCl in aquatic ecosystems, but none have explored the potential impacts of road salt alternatives or additives on aquatic food webs. 2. We assessed the effects of three road salts (NaCl, MgCl2 and ClearLane (TM)) and two road salts mixed with organic additives (GeoMelt (TM) and Magic Salt (TM)) on food webs in experimental aquatic communities, with environmentally relevant concentrations, standardized by chloride concentration. 3. We found that NaCl had few effects on aquatic communities. However, the microbial breakdown of organic additives initially reduced dissolved oxygen. Additionally, microbial activity likely transformed unusable phosphorus from the organic additives to usable phosphorus for algae, which increased algal growth. The increase in algal growth led to an increase in zooplankton abundance. Finally, MgCl2 - a common alternative to NaCl - reduced compositional differences of zooplankton, and at low concentrations increased the abundance of amphipods. 4. Synthesis and applications. Our results indicate that alternative road salts (to NaCl), and road salt additives can alter the abundance and composition of organisms in freshwater food webs at multiple trophic levels, even at low concentrations. Consequently, road salt alternatives and additives might alter ecosystem function and ecosystem services. Therefore, transportation agencies should use caution in applying road salt alternatives and additives. A comprehensive investigation of road salt alternatives and road salt additives should be conducted before wide-scale use is implemented. Further research is also needed to determine the impacts of salt additives and alternatives on higher trophic levels, such as amphibians and fish.

  • 13.
    Stoler, A. B.
    et al.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Troy, NY 12180 USA..
    Mattes, B. M.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Troy, NY 12180 USA..
    Hintz, W. D.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Troy, NY 12180 USA..
    Jones, D. K.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Troy, NY 12180 USA..
    Lind, Lovisa
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Troy, NY .;Swedish Univ Agr Sci, S Umea, Sweden..
    Schuler, M. S.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Troy, NY 12180 USA..
    Relyea, R. A.
    Rensselaer Polytech Inst, Darrin Fresh Water Inst, Troy, NY 12180 USA..
    Effects of a common insecticide on wetland communities with varying quality of leaf litter inputs2017In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 226, p. 452-462Article in journal (Refereed)
    Abstract [en]

    Chemical contamination of aquatic systems often co-occurs with dramatic changes in surrounding terrestrial vegetation. Plant leaf litter serves as a crucial resource input to many freshwater systems, and changes in litter species composition can alter the attributes of freshwater communities. However, little is known how variation in litter inputs interacts with chemical contaminants. We investigated the ecological effects resulting from changes in tree leaf litter inputs to freshwater communities, and how those changes might interact with the timing of insecticide contamination. Using the common insecticide malathion, we hypothesized that inputs of nutrient-rich and labile leaf litter (e.g., elm [Ulmus spp.] or maple [Acer spp.]) would reduce the negative effects of insecticides on wetland communities relative to inputs of recalcitrant litter (e.g., oak [Quercus spp.]). We exposed artificial wetland communities to a factorial combination of three litter species treatments (elm, maple, and oak) and four insecticide treatments (no insecticide, small weekly doses of 10 mu g L-1, and either early or late large doses of 50 mu g L-1). Communities consisted of microbes, algae, snails, amphipods, zooplankton, and two species of tadpoles. After two months, we found that maple and elm litter generally induced greater primary and secondary production. Insecticides induced a reduction in the abundance of amphipods and some zooplankton species, and increased phytoplanlcton. In addition, we found interactive effects of litter species and insecticide treatments on amphibian responses, although specific effects depended on application regime. Specifically, with the addition of insecticide, elm and maple litter induced a reduction in gray tree frog survival, oak and elm litter delayed tree frog metamorphosis, and oak and maple litter reduced green frog tadpole mass. Our results suggest that attention to local forest composition, as well as the timing of pesticide application might help ameliorate the harmful effects of pesticides observed in freshwater systems. (C) 2017 Elsevier Ltd. All rights reserved.

  • 14.
    Stoler, Aaron B.
    et al.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Walker, Brent M.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Hintz, William D.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Jones, Devin K.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Lind, Lovisa
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Mattes, Brian M.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Schuler, Matthew S.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Relyea, Rick A.
    Rensselaer Polytech Inst, Dept Biol Sci, Troy, NY 12180 USA..
    Combined Effects Of Road Salt And An Insecticide On Wetland Communities2017In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 36, no 3, p. 771-779Article in journal (Refereed)
    Abstract [en]

    As the numbers of chemical contaminants in freshwater ecosystems increase, it is important to understand whether contaminants interact in ecologically important ways. The present study investigated the independent and interactive effects of 2 contaminants that frequently co-occur in freshwater environments among higher latitudes, including a commonly applied insecticide (carbaryl) and road salt (NaCl). The hypothesis was that the addition of either contaminant would result in a decline in zooplankton, an algal bloom, and the subsequent decline of both periphyton and periphyton consumers. Another hypothesis was that combining the contaminants would result in synergistic effects on community responses. Outdoor mesocosms were used with communities that included phytoplankton, periphyton, zooplankton, amphipods, clams, snails, and tadpoles. Communities were exposed to 4 environmentally relevant concentrations of salt (27 mg Cl- L-1, 77 mg Cl- L-1, 277 mg Cl- L-1, and 727 mg Cl- L-1) fully crossed with 4 carbaryl treatments (ethanol, 0 mu gL(-1), 5 mu g L-1, and 50 mu g L-1) over 57 d. Contaminants induced declines in rotifer and cladoceran zooplankton, but only carbaryl induced an algal bloom. Consumers exhibited both positive and negative responses to contaminants, which were likely the result of both indirect community interactions and direct toxicity. In contrast to the hypothesis, no synergistic effects were found, although copepod densities declined when high concentrations of both chemicals were combined. The results suggest that low concentrations of salt and carbaryl are likely to have mostly independent effects on aquatic communities. (C) 2016 SETAC

  • 15.
    Su, X.
    et al.
    School of Life Sciences, Southwest University, Chongqing, China; Umeå universitet.
    Polvi, L. E.
    Umå universitet.
    Lind, Lovisa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Umeå universitet.
    Pilotto, F.
    Umår universitet.
    Nilsson, C.
    Swedish University of Agricultural Sciences, Umeå.
    Importance of landscape context for post-restoration recovery of riparian vegetation2019In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 64, no 5, p. 1015-1028Article in journal (Refereed)
    Abstract [en]

    We tested whether the recovery of riparian vegetation along rapids that have been restored after channelisation for timber floating can be predicted based on floristic and geomorphic characteristics of surrounding landscape units. Our study was located along tributary stream networks, naturally fragmented in rapids, slow-flowing reaches, and lakes (i.e. process domains), in the Vindel River catchment in northern Sweden. We tested whether landscape characteristics, specifically to what extent the geomorphology (affecting local abiotic conditions), species richness, and species composition (representing the species pool for recolonisation), as well as the proximity to various upstream process domains (determining the dispersal potential), can predict post-restoration recovery of riparian vegetation. Our results indicate that post-restoration recovery of riparian vegetation richness or composition is not strongly related to landscape-scale species pools in these streams. The restored rapids were most similar to upstream rapids, geomorphically and floristically, including plant traits. Species richness of adjacent landscape units (upstream process domains or lateral upland zone) did not correlate with that of restored rapids, and proximity of upstream rapids or other process domains was only weakly influential, thus diminishing support for the hypothesis that hydrochory or other means of propagule dispersal plays a strong role in riparian vegetation community organisation after restoration in this fragmented stream network. We conclude that, in these naturally fragmented stream systems with three discrete process domains (rapids, slow-flowing reaches and lakes), hydrochory is probably not the main predictor for short-term riparian vegetation recovery. Therefore, other factors than landscape context can serve in prioritising restoration and, in these systems, local factors are likely to outweigh landscape connectivity in the recovery of riparian vegetation.

  • 16. Weber, Christine
    et al.
    Nilsson, Christer
    Lind, Lovisa
    Umeå University, Sweden.
    Alfredsen, Knut T
    Polvi, Lina E
    Winter disturbances and riverine fish in temperate and cold regions2013In: BioScience, ISSN 0006-3568, E-ISSN 1525-3244, Vol. 63, no 3, p. 199-210Article in journal (Refereed)
    Abstract [en]

    Winter is a critical period for aquatic organisms; however, little is known about the ecological significance of its extreme events. Here, we link winter ecology and disturbance research by synthesizing the impacts of extreme winter conditions on riverine habitats and fish assemblages in temperate and cold regions. We characterize winter disturbances by their temporal pattern and abiotic effects, explore how various drivers influence fish, and discuss human alterations of winter disturbances and future research needs. We conclude that (a) more data on winter dynamics are needed to identify extreme events, (b) winter ecology and disturbance research should test assumptions of practical relevance for both disciplines, (c) hydraulic and population models should incorporate winter- and disturbance-specific aspects, and (d) management for sustainability requires that river managers work proactively by including anticipated future alterations in the design of restoration and conservation activities.

1 - 16 of 16
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