Change search
ReferencesLink to record
Permanent link

Direct link
Effects of fine wood on macroinvertebrate drift in four boreal forest streams
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
2016 (English)In: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 765, no 1, 317-327 p.Article in journal (Refereed) PublishedText
Abstract [en]

Most studies of stream wood have focused on pieces a parts per thousand yen0.1 m diameter. However, this approach may overlook an important feature of small streams, where wood < 0.1 m can constitute the majority of wood pieces. We examined the effect of fine wood (FW) on local drift of stream macroinvertebrates. The study was carried out at seven sites in four boreal forest streams, from early June to mid-August 2011. This was done by anchoring bundles of FW at each site and measuring drift upstream and downstream of each bundle. We hypothesized that FW would increase drift density, biomass and diversity of aquatic invertebrates. Ten weeks after FW addition, aquatic drift density was higher downstream than upstream of FW bundles, while drift biomass and drift diversity did not differ significantly downstream and upstream of FW.

Place, publisher, year, edition, pages
2016. Vol. 765, no 1, 317-327 p.
Keyword [en]
Invertebrates, Colonization, FWD, In-stream wood, Small woody debris
National Category
Biological Sciences
Research subject
Biology
Identifiers
URN: urn:nbn:se:kau:diva-40971DOI: 10.1007/s10750-015-2423-xISI: 000366641200022OAI: oai:DiVA.org:kau-40971DiVA: diva2:908865
Available from: 2016-03-03 Created: 2016-03-03 Last updated: 2016-09-02Bibliographically approved
In thesis
1. Effects of fine woody debris on juvenile brown trout (Salmo trutta) and drifting invertebrates
Open this publication in new window or tab >>Effects of fine woody debris on juvenile brown trout (Salmo trutta) and drifting invertebrates
2014 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

In boreal forest streams, woody debris is an important habitat component. Stream invertebrates and salmonids such as brown trout benefit from in-stream wood. The studies presented in this thesis explore how drifting stream invertebrates respond to addition of fine woody debris, and how young-of-the-year (0+) brown trout behave in habitats with and without fine woody debris. The first paper reports results from a field experiment where fine woody debris was added to streams, and invertebrate drift was measured in order to detect impacts of the fine woody debris on drift density, biomass and taxon diversity. In the end of the season, the fine woody debris-affected drift samples showed higher density, biomass and taxon diversity than the control samples. In the second paper, I describe effects of fine woody debris on 0+ brown trout, studied in laboratory stream channels. Trout were tested in habitats without fine woody debris, with an intermediate fine woody debris density, and with a high fine woody debris density. Swimming activity and foraging time were significantly lower when fine woody debris was present than when it was absent. More time was spent sheltering at the high fine woody debris density than at the intermediate one. The increasing exploitation of fine woody debris for biofuel purposes should be considered in relation to the effects on brown trout and stream invertebrate habitat.

Place, publisher, year, edition, pages
Karlstad: Karlstads universitet, 2014. 22 p.
Series
Karlstad University Studies, ISSN 1403-8099 ; 2014:15
Keyword
brown trout, juvenile, stream, woody debris, invertebrates, fine woody debris
National Category
Natural Sciences
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-31672 (URN)978-91-7063-545-8 (ISBN)
Presentation
2014-04-29, 11D227, Universitetsg 2, Karlstad, 10:00 (English)
Opponent
Supervisors
Note

Artikel 1 ingick i avhandlingen som manuskript med titeln "Effects of fine wood addition on invertebrate drift in boreal forest streams". Nu publicerad.

Available from: 2014-04-07 Created: 2014-03-10 Last updated: 2016-03-03Bibliographically approved
2. Fine stream wood: effects on drift and brown trout (Salmo trutta) growth and behaviour
Open this publication in new window or tab >>Fine stream wood: effects on drift and brown trout (Salmo trutta) growth and behaviour
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Stream ecosystems and their riparian zones have previously been regarded as two different ecosystems, linked through numerous reciprocal subsidies. Today, ecologists agree that the stream and the riparian zone should be regarded as one system, the stream-riparian ecosystem, which is characterised largely by the subsidies between land and water. The terrestrial subsidies to the stream affect stream-living biota in several ways, some of which are well-known while others less so. The input of wood to the stream from the riparian zone is believed to play an important role in the population dynamics of stream-living fish. In this doctoral thesis, I explore effects of fine stream wood (FW, <10 cm diameter) on wild stream-living young-of-the-year brown trout (Salmo trutta) by reporting and discussing results from laboratory, semi-natural and field experiments. My results show that the local density of drifting prey is higher in the presence of FW than in its absence, and also that young-of-the-year brown trout decrease their diurnal foraging time and prey capture success when FW is added to their habitat. I show that trout decrease their swimming activity in the presence of FW, aggregate in FW bundles, and have lower growth rates than trout without FW access. Also, the degree of sheltering in FW bundles was higher during day than at night in a study performed at low water temperatures; moreover, the presence of an ectothermic nocturnal predator (burbot, Lota lota) did not affect the degree of sheltering in FW bundles by trout. Taken together, my results indicate that young-of-the-year brown trout with access to FW bundles spend considerable amounts of time sheltering in the FW, and by doing so they miss the opportunity for higher growth and foraging rates outside of the shelter. The most probable explanation for this behaviour is that growth is traded off against survival, i.e., the predation risk is higher outside of the shelter.

Abstract [en]

Stream ecosystems and their riparian zones have previously been regarded as two different ecosystems, linked through numerous reciprocal subsidies. Today, ecologists agree that the stream and the riparian zone should be regarded as one system, the stream-riparian ecosystem, which is characterised largely by the subsidies between land and water. In this doctoral thesis, I explore one such subsidy – the input of fine stream wood (FW) to streams. Wild stream-living young-of-the-year brown trout (Salmo trutta) was chosen as study species. My results show that the local density of drifting prey is higher in the presence of FW than in its absence, and that young-of-the-year brown trout decrease their diurnal foraging time and prey capture success when FW is added to their habitat. I show that trout decrease their activity in the presence of FW, aggregate in FW bundles, and have lower growth rates than trout without FW access. Taken together, my results indicate that young-of-the-year brown trout spend considerable amounts of time in FW bundles, and by doing so they miss the opportunity for higher growth and foraging rates outside of the shelter. The most probable explanation for this behaviour is that growth is traded off against survival.

Place, publisher, year, edition, pages
Karlstad University Press, 2016. 43 p.
Series
Karlstad University Studies, ISSN 1403-8099 ; 34
Keyword
stream fish, wood, salmonid, trout, aquatic invertebrates, behaviour, sheltering
National Category
Biological Sciences
Research subject
Biology
Identifiers
urn:nbn:se:kau:diva-44537 (URN)978-91-7063-715-5 (ISBN)
External cooperation:
Public defence
2016-09-23, 9C 203, Universitetsgatan 2, Karlstad, 10:15 (English)
Opponent
Supervisors
Available from: 2016-09-02 Created: 2016-08-01 Last updated: 2016-09-02Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Enefalk, ÅsaBergman, Eva
By organisation
Department of Environmental and Life Sciences
In the same journal
Hydrobiologia
Biological Sciences

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 31 hits
ReferencesLink to record
Permanent link

Direct link