umu.sePublikasjoner
Endre søk
Begrens søket
1 - 5 of 5
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Dietrich, Anna L.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Nilsson, Christer
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Jansson, Roland
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    A phytometer study evaluating the effects of stream restoration on riparian vegetation2016Inngår i: Ecohydrology, ISSN 1936-0584, E-ISSN 1936-0592, Vol. 9, nr 4, s. 646-658Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Channelization of streams and rivers to facilitate timber floating has cut off riparian zones from the channel, covered them with coarse sediment and resulted in less flooding. Restoration measures aiming to counteract these impacts are expected to create a higher, more natural hydrological variability and enhance site quality for riparian plants. In a long-term field experiment, we evaluated the effect of flooding regime on riparian plant performance by measuring survival and biomass increment of two transplanted phytometer species, a grass (Molinia caerulea) and a forb (Filipendula ulmaria). We also analysed the number and duration of flooding events in channelized and restored stream and river reaches with an indirect method using diurnal temperature oscillation. We found that flow duration was higher, with significantly more flood events at restored compared with channelized sites in medium-sized and large watercourses, particularly during the summer months. Phytometer performance was better at restored sites, and it was positively correlated with duration and frequency of summer flooding, indicating that more but less intense floods after restoration improved site conditions for phytometer growth. This may not only result from an increased heterogeneity in channel morphology caused by the return of boulders but can probably also be attributed to a reduced current velocity at restored sites. Flood variables were more often correlated with other abiotic variables at restored than at channelized sites, which points to an increased land-water connectivity as a result of restoration. 

  • 2.
    Kuglerova, Lenka
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Department of Forest and ConservationSciences, University of British Columbia,Vancouver, Canada.
    Botkova, Kamila
    Jansson, Roland
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Responses of riparian plants to habitat changes following restoration of channelized streams2017Inngår i: Ecohydrology, ISSN 1936-0584, E-ISSN 1936-0592, Vol. 10, nr 1, artikkel-id UNSP e1798Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The ecological effects of stream restoration were evaluated by comparing riparian vegetation, flooding, and habitat properties between channelized and two types of restored streams in northern Sweden. Channelized streams were straightened and cleared of in-stream boulders and wood >50 years ago to facilitate timber floating. Basic restoration (performed 8-10 years ago) returned cleared material back to the channels, and enhanced restoration (3 years ago) added large structural elements (boulders and downed trees) to previously basic-restored streams. Riparian inundation duration increased only after enhanced restoration. Similarly, enhanced-restored reaches had the highest amount of substrate available for plant establishment compared to channelized and basic-restored streams. In contrast, soil biochemical properties (pH and C:N ratio) did not improve following either restoration effort. Riparian plant cover was higher at both restored types than channelized reaches. Plant species richness was higher at plot-scale level (0.25 m(2)) at both restored types in the most species-rich elevation levels compared to channelized reaches, whereas at the reach-scale (>700 m(2) of riparian area), species richness did not differ among stream types. Similarly, species composition segregated between channelized and restored reaches only at the plot scale. We found no significant differences in riparian vegetation between the two restored types. The lack of positive responses of vegetation to enhanced restoration and to variables that changed immediately after restoration (inundation, habitat area) implies that responses were either slower than expected or the changes in hydrology and substrate availability were not as important for riparian flora as believed.

  • 3.
    Nilsson, Christer
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Polvi, Lina E
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Gardeström, Johanna
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Maher Hasselquist, Eliza
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Lind, Lovisa
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Sarneel, Judith M
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Riparian and in-stream restoration of boreal streams and rivers: success or failure?2015Inngår i: Ecohydrology, ISSN 1936-0584, E-ISSN 1936-0592, Vol. 8, nr 5, s. 753-764Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 4.
    Sarneel, Judith M.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Ecology and Biodiversity Group and Plant Ecophysiology Group, Utrecht University, Utrecht, The Netherlands.
    Effects of experimental snowmelt and rain on dispersal of six plant species2016Inngår i: Ecohydrology, ISSN 1936-0584, E-ISSN 1936-0592, Vol. 9, nr 8, s. 1464-1470Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Water flows affect dispersal of propagules of many plant species, and rivers and streams are therefore very important dispersal vectors. However, small water flows such as trough rain and snowmelt are much more common, but their effects on dispersal are barely studied. The importance of this form of dispersal deserves attention, especially when considering that climate change is predicted to change the amounts of rain and snow worldwide. Dispersal through melting snow and rain was addressed experimentally, using artificial soils mounted on slopes with different angles and subjected to a melting snow pack or an equivalent amount of dripping water. Seeds on the soil moved on average 3.02 cm (+/- 1.81 SE) in rain treatments and 0.23 cm (+/- 0.3 SE) in snowmelt treatments. Tracking plastic granules in field conditions further showed that snowmelt exhibited minimal dispersal capacity. Dispersal distances by rain were enhanced by increasing slope angles and with decreasing seed volume. Given that many species in cold environments have small seeds, dispersal by rain could provide an important (secondary) dispersal mechanism in these habitats.

  • 5.
    Su, Xiaolei
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Key Laboratory of Eco‐Environments inThree Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, PR China.
    Lind, Lovisa
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. NRRV, Department of Environmental and Life Sciences, Karlstad University, Karlstad, Sweden.
    Polvi, Lina E.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Nilsson, Christer
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Variation in hydrochory among lakes and streams: effects of channel planform, roughness, and currents2019Inngår i: Ecohydrology, ISSN 1936-0584, E-ISSN 1936-0592, Vol. 12, nr 5, artikkel-id e2091Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The configuration of channels in stream networks is vital for their connectivity, biodiversity, and metacommunity dynamics. We compared the capacity of three process domains-lakes, slow-flowing reaches, and rapids-to disperse and retain plant propagules by releasing small wooden cubes as propagule mimics during the spring flood and recording their final locations. We also measured the geomorphic characteristics (planform, longitudinal profile, cross-sectional morphology, and wood) of each process domain. The three process domains all differed in morphology and hydraulics, and those characteristics were important in shaping the transport capacity of mimics. On average, lakes retained more mimics than slow-flowing reaches but did not differ from the retainment of rapids. Living macrophytes were the most efficient element trapping mimics. In rapids and slow-flowing reaches, most trapped mimics remained floating, whereas in lakes, most mimics ended up on the banks. The decay curves of retention varied substantially among and within process domains. The results suggest that managers who rely on natural recovery of restored sites by means of plant immigration may benefit from understanding landscape patterns when deciding upon the location of restoration measures in stream networks.

1 - 5 of 5
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf