Skip header and navigation

Refine By

10 records – page 1 of 1.

The alternative prey hypothesis revisited: Still valid for willow ptarmigan population dynamics.

https://arctichealth.org/en/permalink/ahliterature296187
Source
PLoS One. 2018; 13(6):e0197289
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
2018
Author
Jo Inge Breisjøberget
Morten Odden
Per Wegge
Barbara Zimmermann
Harry Andreassen
Author Affiliation
Faculty of Applied Ecology and Agricultural Sciences, Inland Norway University of Applied Sciences, Campus Evenstad, Koppang, Norway.
Source
PLoS One. 2018; 13(6):e0197289
Date
2018
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Betula - growth & development
Climate change
Food chain
Foxes - physiology
Models, Biological
Norway
Population Dynamics
Rodentia - physiology
Salix - growth & development
Abstract
The alternative prey hypothesis predicts that the interaction between generalist predators and their main prey is a major driver of population dynamics of alternative prey species. In Fennoscandia, changes in climate and human land use are assumed to alter the dynamics of cyclic small rodents (main prey) and lead to increased densities and range expansion of an important generalist predator, the red fox Vulpes vulpes. In order to better understand the role of these potential changes in community structure on an alternative prey species, willow ptarmigan Lagopus lagopus, we analyzed nine years of population census data from SE Norway to investigate how community interactions affected their population dynamics. The ptarmigan populations showed no declining trend during the study period, and annual variations corresponded with marked periodic small rodent peaks and declines. Population growth and breeding success were highly correlated, and both demographic variables were influenced by an interaction between red fox and small rodents. Red foxes affected ptarmigan negatively only when small rodent abundance was low, which is in accordance with the alternative prey hypothesis. Our results confirm the important role of red fox predation in ptarmigan dynamics, and indicate that if small rodent cycles are disrupted, this may lead to decline in ptarmigan and other alternative prey species due to elevated predation pressure.
Notes
Cites: Oecologia. 2002 Jul;132(2):213-220 PMID 28547354
Cites: Oecologia. 1985 Oct;67(3):394-402 PMID 28311574
Cites: Nature. 2003 Jan 2;421(6918):37-42 PMID 12511946
Cites: Science. 2009 Sep 11;325(5946):1355-8 PMID 19745143
Cites: Pest Manag Sci. 2014 Dec;70(12):1769-79 PMID 25256611
Cites: Anim Behav. 1998 Nov;56(5):1137-1144 PMID 9819329
Cites: Oecologia. 1978 Jan;32(2):141-152 PMID 28309394
Cites: Proc Biol Sci. 2002 May 22;269(1495):991-7 PMID 12028754
Cites: Nature. 2008 Nov 6;456(7218):93-7 PMID 18987742
Cites: Proc Biol Sci. 2017 Nov 15;284(1866):null PMID 29118133
Cites: Ecol Evol. 2016 Dec 14;7(1):115-124 PMID 28070280
Cites: Ecol Lett. 2007 Mar;10(3):197-206 PMID 17305803
Cites: J Anim Ecol. 2011 Sep;80(5):1049-60 PMID 21477201
Cites: Ambio. 2015 Jan;44 Suppl 1:S39-50 PMID 25576279
Cites: Proc Biol Sci. 2005 Oct 7;272(1576):2045-9 PMID 16191615
Cites: Oecologia. 1984 May;62(2):199-208 PMID 28310714
Cites: J Anim Ecol. 2009 May;78(3):636-45 PMID 19040680
Cites: Oecologia. 1990 Apr;82(4):527-530 PMID 28311478
Cites: PLoS One. 2017 Apr 6;12 (4):e0175291 PMID 28384313
Cites: J Anim Ecol. 2011 Jan;80(1):244-58 PMID 21054381
Cites: J Anim Ecol. 2006 Jan;75(1):156-66 PMID 16903053
PubMed ID
29874270 View in PubMed
Less detail

Ammonium nitrate fertiliser production based on biomass - environmental effects from a life cycle perspective.

https://arctichealth.org/en/permalink/ahliterature95545
Source
Bioresour Technol. 2008 Nov;99(17):8034-41
Publication Type
Article
Date
Nov-2008
Author
Ahlgren Serina
Baky Andras
Bernesson Sven
Nordberg Ke
Norén Olle
Hansson Per-Anders
Author Affiliation
Swedish University of Agricultural Sciences, Department of Energy and Technology, P.O. Box 7032, SE 750 07 Uppsala, Sweden. Serina.Ahlgren@et.slu.se
Source
Bioresour Technol. 2008 Nov;99(17):8034-41
Date
Nov-2008
Language
English
Publication Type
Article
Keywords
Biomass
Environment
Eutrophication
Fertilizers
Fossil Fuels
Greenhouse Effect
Nitrates - chemical synthesis
Salix - growth & development
Abstract
Ammonium nitrate and calcium ammonium nitrate are the most commonly used straight nitrogen fertilisers in Europe, accounting for 43% of the total nitrogen used for fertilisers. They are both produced in a similar way; carbonate can be added as a last step to produce calcium ammonium nitrate. The environmental impact, fossil energy input and land use from using gasified biomass (cereal straw and short rotation willow (Salix) coppice) as feedstock in ammonium nitrate production were studied in a cradle-to-gate evaluation using life cycle assessment methodology. The global warming potential in the biomass systems was only 22-30% of the impact from conventional production using natural gas. The eutrophication potential was higher for the biomass systems due to nutrient leaching during cultivation, while the acidification was about the same in all systems. The primary fossil energy use was calculated to be 1.45 and 1.37MJ/kg nitrogen for Salix and straw, respectively, compared to 35.14MJ for natural gas. The biomass production was assumed to be self-supporting with nutrients by returning part of the ammonium nitrate produced together with the ash from the gasification. For the production of nitrogen from Salix, it was calculated that 3914kg of nitrogen can be produced every year from 1ha, after that 1.6% of the produced nitrogen has been returned to the Salix production. From wheat straw, 1615kg of nitrogen can be produced annually from 1ha, after that 0.6% of the nitrogen has been returned.
PubMed ID
18440225 View in PubMed
Less detail

Aphid-willow interactions in a high Arctic ecosystem: responses to raised temperature and goose disturbance.

https://arctichealth.org/en/permalink/ahliterature258051
Source
Glob Chang Biol. 2013 Dec;19(12):3698-708
Publication Type
Article
Date
Dec-2013
Author
Mark A K Gillespie
Ingibjörg S Jónsdóttir
Ian D Hodkinson
Elisabeth J Cooper
Author Affiliation
Institute of Integrative and Comparative Biology, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK.
Source
Glob Chang Biol. 2013 Dec;19(12):3698-708
Date
Dec-2013
Language
English
Publication Type
Article
Keywords
Animals
Aphids - growth & development - physiology
Arctic Regions
Climate change
Geese - physiology
Herbivory
Population Dynamics
Reproduction
Salix - growth & development - physiology
Seasons
Svalbard
Temperature
Abstract
Recently, there have been several studies using open top chambers (OTCs) or cloches to examine the response of Arctic plant communities to artificially elevated temperatures. Few, however, have investigated multitrophic systems, or the effects of both temperature and vertebrate grazing treatments on invertebrates. This study investigated trophic interactions between an herbivorous insect (Sitobion calvulum, Aphididae), a woody perennial host plant (Salix polaris) and a selective vertebrate grazer (barnacle geese, Branta leucopsis). In a factorial experiment, the responses of the insect and its host to elevated temperatures using open top chambers (OTCs) and to three levels of goose grazing pressure were assessed over two summer growing seasons (2004 and 2005). OTCs significantly enhanced the leaf phenology of Salix in both years and there was a significant OTC by goose presence interaction in 2004. Salix leaf number was unaffected by treatments in both years, but OTCs increased leaf size and mass in 2005. Salix reproduction and the phenology of flowers were unaffected by both treatments. Aphid densities were increased by OTCs but unaffected by goose presence in both years. While goose presence had little effect on aphid density or host plant phenology in this system, the OTC effects provide interesting insights into the possibility of phenological synchrony disruption. The advanced phenology of Salix effectively lengthens the growing season for the plant, but despite a close association with leaf maturity, the population dynamics of the aphid appeared to lack a similar phenological response, except for the increased population observed.
PubMed ID
23749580 View in PubMed
Less detail

Are heat and cold resistance of Arctic species affected by successive extreme temperature events?

https://arctichealth.org/en/permalink/ahliterature95738
Source
New Phytologist. 2006;170(2):291-300
Publication Type
Article
Date
2006
Author
Marchand, FL
Kockelbergh, F
van de Vijver, B
Beyens, L
Nijs, I
Author Affiliation
Research Group Plant and Vegetation Ecology, Department of Biology, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, B-2610 Wilrijk, Belgium.
Source
New Phytologist. 2006;170(2):291-300
Date
2006
Language
English
Publication Type
Article
Keywords
Arctic Regions
Carex Plant - growth & development - physiology
Chlorophyll - metabolism
Cold Climate
Ericaceae - growth & development - physiology
Fluorescence
Greenhouse Effect
Hot Temperature
Photosynthesis - physiology
Photosystem II Protein Complex - physiology
Plant Leaves - growth & development - physiology
Polygonum - growth & development - physiology
Salix - growth & development - physiology
Species Specificity
Abstract
Extreme temperature events are projected to increase in frequency in a future climate. As successive extremes could occur more frequently, patches of vulnerable tundra vegetation were exposed to two consecutive heat waves (HWs) of 10 d each, with a 5-d recovery period in between. Surface temperatures during the HWs were increased approximately 6 degrees C using infrared irradiation sources. In three of the four target species (Pyrola grandiflora, Polygonum viviparum and Carex bigelowii), plant conditions improved upon the first exposure. Depending on species, leaf relative growth, leaf chlorophyll content or maximal photochemical efficiency was increased. In P. grandiflora the positive effects of the heat on the photosynthetic apparatus led to augmented net photosynthesis. By contrast, Salix arctica responded mainly negatively, indicating species-specific responses. During the second HW, leaf mortality suddenly increased, indicating that the heat stress induced by the extreme events lasted too long and negatively influenced the species resistance to high temperature. After the HWs, when plants were exposed to (low) ambient temperatures again, plant performance deteriorated further, indicating possible loss of cold resistance.
PubMed ID
16608454 View in PubMed
Less detail

Biogenic volatile organic compound emissions along a high arctic soil moisture gradient.

https://arctichealth.org/en/permalink/ahliterature290127
Source
Sci Total Environ. 2016 Dec 15; 573:131-138
Publication Type
Journal Article
Date
Dec-15-2016
Author
Sarah Hagel Svendsen
Frida Lindwall
Anders Michelsen
Riikka Rinnan
Author Affiliation
Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Universitetsparken 15, DK -2100 Copenhagen E, Denmark; Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK -1350 Copenhagen K, Denmark.
Source
Sci Total Environ. 2016 Dec 15; 573:131-138
Date
Dec-15-2016
Language
English
Publication Type
Journal Article
Keywords
Air Pollutants - analysis
Arctic Regions
Climate change
Ecosystem
Environmental Monitoring - methods
Ericaceae - growth & development
Greenland
Rosaceae - growth & development
Salix - growth & development
Soil - chemistry
Volatile Organic Compounds - analysis
Water - analysis
Abstract
Emissions of biogenic volatile organic compounds (BVOCs) from terrestrial ecosystems are important for the atmospheric chemistry and the formation of secondary organic aerosols, and may therefore influence the climate. Global warming is predicted to change patterns in precipitation and plant species compositions, especially in arctic regions where the temperature increase will be most pronounced. These changes are potentially highly important for the BVOC emissions but studies investigating the effects are lacking. The aim of this study was to investigate the quality and quantity of BVOC emissions from a high arctic soil moisture gradient extending from dry tundra to a wet fen. Ecosystem BVOC emissions were sampled five times in the July-August period using a push-pull enclosure technique, and BVOCs trapped in absorbent cartridges were analyzed using gas chromatography-mass spectrometry. Plant species compositions were estimated using the point intercept method. In order to take into account important underlying ecosystem processes, gross ecosystem production, ecosystem respiration and net ecosystem production were measured in connection with chamber-based BVOC measurements. Highest emissions of BVOCs were found from vegetation communities dominated by Salix arctica and Cassiope tetragona, which had emission profiles dominated by isoprene and monoterpenes, respectively. These results show that emissions of BVOCs are highly dependent on the plant cover supported by the varying soil moisture, suggesting that high arctic BVOC emissions may affect the climate differently if soil water content and plant cover change.
PubMed ID
27552736 View in PubMed
Less detail

Climate regulation, energy provisioning and water purification: Quantifying ecosystem service delivery of bioenergy willow grown on riparian buffer zones using life cycle assessment.

https://arctichealth.org/en/permalink/ahliterature279354
Source
Ambio. 2016 Dec;45(8):872-884
Publication Type
Article
Date
Dec-2016
Author
David Styles
Pål Börjesson
Tina D'Hertefeldt
Klaus Birkhofer
Jens Dauber
Paul Adams
Sopan Patil
Tim Pagella
Lars B Pettersson
Philip Peck
Céline Vaneeckhaute
Håkan Rosenqvist
Source
Ambio. 2016 Dec;45(8):872-884
Date
Dec-2016
Language
English
Publication Type
Article
Keywords
Biofuels
Conservation of Natural Resources - methods
Crops, Agricultural - growth & development
Ecosystem
Eutrophication
Global Warming - prevention & control
Greenhouse Effect
Renewable Energy
Salix - growth & development
Sweden
Water Purification - methods
Abstract
Whilst life cycle assessment (LCA) boundaries are expanded to account for negative indirect consequences of bioenergy such as indirect land use change (ILUC), ecosystem services such as water purification sometimes delivered by perennial bioenergy crops are typically neglected in LCA studies. Consequential LCA was applied to evaluate the significance of nutrient interception and retention on the environmental balance of unfertilised energy willow planted on 50-m riparian buffer strips and drainage filtration zones in the Skåne region of Sweden. Excluding possible ILUC effects and considering oil heat substitution, strategically planted filter willow can achieve net global warming potential (GWP) and eutrophication potential (EP) savings of up to 11.9 Mg CO2e and 47 kg PO4e ha(-1) year(-1), respectively, compared with a GWP saving of 14.8 Mg CO2e ha(-1) year(-1) and an EP increase of 7 kg PO4e ha(-1) year(-1) for fertilised willow. Planting willow on appropriate buffer and filter zones throughout Skåne could avoid 626 Mg year(-1) PO4e nutrient loading to waters.
PubMed ID
27240661 View in PubMed
Less detail

Evaluating human-disturbed habitats for recovery planning of endangered plants.

https://arctichealth.org/en/permalink/ahliterature266295
Source
J Environ Manage. 2015 Mar 1;150:157-63
Publication Type
Article
Date
Mar-1-2015
Author
Julie Robinson
Luise Hermanutz
Source
J Environ Manage. 2015 Mar 1;150:157-63
Date
Mar-1-2015
Language
English
Publication Type
Article
Keywords
Ecosystem
Environmental monitoring
Environmental Restoration and Remediation
Humans
Newfoundland and Labrador
Ontario
Salix - growth & development
Abstract
The recovery potential of endangered species is limited by the high prevalence of human-modified habitats, while effective in situ conservation strategies to identify and restore disturbed habitat within species ranges are lacking. Our goal was to determine the impact of human disturbance on the endangered endemic Barrens willow (Salix jejuna) to provide science-based protocols for future restoration of disturbed habitats; a key component of conservation and recovery plans for many rare plant species. Our study examined differences in substrate (e.g., % total plant cover, % species cover, substrate type) and vegetation in naturally- (via frost activity) vs human-disturbed limestone barrens (Newfoundland, Canada), across the entire species range of the endangered Barrens willow. There were distinct differences in substrate conditions and vegetation community structure between naturally- and human-disturbed limestone barrens habitat throughout the narrow range of this endemic willow. Human-disturbed sites are more homogeneous and differ significantly from the naturally-disturbed sites having a much coarser substrate (30% more gravel) with less fine grained sands, less exposed bedrock, decreased soil moisture, increased nitrogen content, and reduced phosphorus content. Substrate differences can inhibit return to the natural freeze-thaw disturbance regime of the limestone barrens, negatively affecting long-term persistence of this, and other rare plants. The structure of associated vegetation (specifically woody species presence) negatively affected willow abundance but was not linked to disturbance type. Human-disturbed sites are potential candidates for endangered plant recovery habitat if natural ecosystem processes, vegetation community structure, and habitat heterogeneity are restored, thereby supporting the establishment of long term viable populations.
PubMed ID
25485935 View in PubMed
Less detail

Experimental evidence that ptarmigan regulate willow bud production to their own advantage.

https://arctichealth.org/en/permalink/ahliterature270262
Source
Oecologia. 2015 Jul;178(3):773-81
Publication Type
Article
Date
Jul-2015
Author
Katie S Christie
R W Ruess
Source
Oecologia. 2015 Jul;178(3):773-81
Date
Jul-2015
Language
English
Publication Type
Article
Keywords
Alaska
Animals
Ecosystem
Food Preferences
Galliformes
Herbivory
Salix - growth & development - metabolism
Seasons
Snow
Abstract
In some ecosystems, vertebrate herbivores increase the nutritional quality and biomass of their food source through repeated grazing, thereby manipulating their environment to support higher densities of animals. We tested whether ptarmigan (Lagopus lagopus and L. muta) are capable of regulating the nutritional quality, abundance, and availability of feltleaf willow (Salix alaxensis) buds using a simulated browsing experiment and a feeding preference study with wild birds. Simulated ptarmigan browsing resulted in smaller buds, but greater numbers of buds per shoot. Furthermore, browsing altered the morphology of willow branches such that buds were at higher densities and closer to snow level compared to unbrowsed controls. Browsing increased the number of willows with accessible buds (buds within 50 cm of snow level) from 55 to 89%, and increased total accessible bud biomass from 113 ± 30 to 129 ± 50 mg/ramet. Browsing did not affect bud nitrogen or carbon concentration and slightly reduced protein precipitation capacity (tannins) in buds the following winter, indicating that ptarmigan browsing does not induce a defensive response in this species. When branches of broomed (previously browsed) and unbroomed willows were placed in the snow at equal heights, ptarmigan showed no preference for either type; however, they obtained more buds from broomed willows. Increased accessibility and density of willow buds caused by browsing has the potential to increase habitat carrying capacity, thereby supporting higher densities of ptarmigan.
PubMed ID
25698142 View in PubMed
Less detail

Phenological sequences reveal aggregate life history response to climatic warming.

https://arctichealth.org/en/permalink/ahliterature95551
Source
Ecology. 2008 Feb;89(2):363-70
Publication Type
Article
Date
Feb-2008
Author
Post Eric S
Pedersen Christian
Wilmers Christopher C
Forchhammer Mads C
Author Affiliation
Department of Biology, Penn State University, 208 Mueller Lab, University Park, Pennsylvania 16802, USA. Esp10@psu.edu
Source
Ecology. 2008 Feb;89(2):363-70
Date
Feb-2008
Language
English
Publication Type
Article
Keywords
Adaptation, Physiological
Betula - growth & development - physiology
Caryophyllaceae - growth & development - physiology
Ecosystem
Greenhouse Effect
Population Dynamics
Population Growth
Salix - growth & development - physiology
Species Specificity
Temperature
Time Factors
Abstract
Climatic warming is associated with organisms breeding earlier in the season than is typical for their species. In some species, however, response to warming is more complex than a simple advance in the timing of all life history events preceding reproduction. Disparities in the extent to which different components of the reproductive phenology of organisms vary with climatic warming indicate that not all life history events are equally responsive to environmental variation. Here, we propose that our understanding of phenological response to climate change can be improved by considering entire sequences of events comprising the aggregate life histories of organisms preceding reproduction. We present results of a two-year warming experiment conducted on 33 individuals of three plant species inhabiting a low-arctic site. Analysis of phenological sequences of three key events for each species revealed how the aggregate life histories preceding reproduction responded to warming, and which individual events exerted the greatest influence on aggregate life history variation. For alpine chickweed (Cerastium alpinum), warming elicited a shortening of the duration of the emergence stage by 2.5 days on average, but the aggregate life history did not differ between warmed and ambient plots. For gray willow (Salix glauca), however, all phenological events monitored occurred earlier on warmed than on ambient plots, and warming reduced the aggregate life history of this species by 22 days on average. Similarly, in dwarf birch (Betula nana), warming advanced flower bud set, blooming, and fruit set and reduced the aggregate life history by 27 days on average. Our approach provides important insight into life history responses of many organisms to climate change and other forms of environmental variation. Such insight may be compromised by considering changes in individual phenological events in isolation.
PubMed ID
18409426 View in PubMed
Less detail

Tree and shrub expansion over the past 34 years at the tree-line near Abisko, Sweden.

https://arctichealth.org/en/permalink/ahliterature130932
Source
Ambio. 2011 Sep;40(6):683-92
Publication Type
Article
Date
Sep-2011
Author
Sara Rundqvist
Henrik Hedenås
Anneli Sandström
Urban Emanuelsson
Håkan Eriksson
Christer Jonasson
Terry V Callaghan
Author Affiliation
Umeå University, Sweden. sara.rundqvist@gmail.com
Source
Ambio. 2011 Sep;40(6):683-92
Date
Sep-2011
Language
English
Publication Type
Article
Keywords
Betula - growth & development
Climate change
Ecosystem
Humans
Plant Development
Salix - growth & development
Sweden
Time Factors
Trees - growth & development
Abstract
Shrubs and trees are expected to expand in the sub-Arctic due to global warming. Our study was conducted in Abisko, sub-arctic Sweden. We recorded the change in coverage of shrub and tree species over a 32- to 34-year period, in three 50 x 50 m plots; in the alpine-tree-line ecotone. The cover of shrubs and trees ( or =3.5 cm) were noted and positions determined. There has been a substantial increase of cover of shrubs and trees, particularly dwarf birch (Betula nana), and mountain birch (Betula pubescens ssp. czerepanovii), and an establishment of aspen (Populus tremula). The other species willows (Salix spp.), juniper (Juniperus communis), and rowan (Sorbus aucuparia) revealed inconsistent changes among the plots. Although this study was unable to identify the causes for the change in shrubs and small trees, they are consistent with anticipated changes due to climate change and reduced herbivory.
Notes
Cites: Nature. 2001 May 31;411(6837):546-711385559
Cites: Ambio. 2002 Aug;Spec No 12:6-1412374061
Cites: Proc Natl Acad Sci U S A. 2006 Jan 31;103(5):1342-616428292
Cites: J Evol Biol. 2007 Jan;20(1):369-8017210030
Cites: Ambio. 2011 Sep;40(6):693-70421954731
Cites: Ambio. 2011 Sep;40(6):555-721954718
Cites: Ambio. 2011 Sep;40(6):600-921954723
Cites: Ambio. 2011 Sep;40(6):672-8221954729
Cites: New Phytol. 2010 Jun;186(4):890-920345642
PubMed ID
21954730 View in PubMed
Less detail

10 records – page 1 of 1.