| 1. |
- Ahrné, Karin, et al.
(författare)
-
Tillstånd och trender för arter och deras livsmiljöer – rödlistade arter i Sverige 2015
- 2015
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- 2015 års upplaga av den svenska rödlistan är den fjärde i ordningen. Den är baserad på IUCN:s rödlistningskriterier och revideras vart femte år. I rödlistan bedöms risken som enskilda arter av djur, växter och svampar löper att försvinna från Sverige. Bedömningen utförs av ArtDatabankens medarbetare i samverkan med över 100 externa experter, indelade i 14 expertkommittéer för olika organismgrupper. Under arbetet med 2015 års rödlista har tillstånd och trender bedömts för 21 600 arter och 1 318 lägre taxa (apomiktiska arter, underarter och varieteter), sammanlagt ca 22 900 taxa. Av de bedömda arterna klassificerades 2 029 som hotade (kategorierna CR, EN och VU) och 4 273 som rödlistade (inkluderar även kategorierna NT, RE och DD). Förhållandet mellan antalet rödlistade och antalet bedömda arter ar 19,8 %, vilket är ungefär samma värde som 2010 och 2005. I denna rapport jämförs antalet och andelen rödlistade arter mellan olika organismgrupper, biotoper, substrat och påverkansfaktorer. Texten ar indelad i en allmän del och åtta kapitel inriktade på olika landskapstyper. Landskapstyperna utgör en grov indelning av landets miljöer enligt följande kategorier: Skog, Jordbrukslandskap, Urbana miljöer, Fjäll, Våtmarker, Sötvatten, Havsstränder och Havsmiljöer. Skogen och jordbrukslandskapet är de artrikaste landskapstyperna med 1 800 respektive 1 400 arter som har en stark anknytning dit, och ytterligare flera hundra arter som förekommer där mer sporadiskt. De faktorer som påverkar flest rödlistade arter i Sverige är skogsavverkning och igenväxning, som båda utgör ett hot mot vardera ca 30 % av de rödlistade arterna. Avverkning minskar arealen av skog där naturliga strukturer och naturlig dynamik upprätthålls, och den orsakar därmed förlust av livsmiljöer. Igenväxning orsakas av ett antal faktorer, bland annat upphörande hävd (bete och slåtter), gödsling, trädplantering och brist på naturliga störningsregimer som t.ex. regelbundna översvämningar kring vattendrag och sjöar. Andra viktiga påverkansfaktorer är fiske, torrläggning av våtmarker, tillbakagång hos värdarter (främst alm och ask som drabbats av invasiva svampsjukdomar), klimatförändringar och konkurrens från invasiva arter. IUCN:s rödlisteindex beräknas för ett urval av de bedömda organismgrupperna. Rödlisteindex visar att skillnaderna mellan rödlistorna från 2000, 2005, 2010 och 2015 är små. Ett par undantag finns dock. Groddjur och stora däggdjur har fått en något förbättrad situation sedan 2000. Totalt förefaller det ändå som att trycket mot Sveriges artstock har förblivit relativt konstant under de senaste 15 åren.
|
|
| 2. |
- Sundberg, Sebastian, et al.
(författare)
-
Havsstränder
- 2015
-
Ingår i: Tillstånd och trender för arter och deras livsmiljöer - rödlistade arter i Sverige 2015. - 9789187853135 ; :17, s. 51-56
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Sveriges mångformiga kust - med sand-, grus- och klippstränder, dyner och strandängar - hyser drygt 270 rödlistade arter för vilka havsstränderna är viktiga livsmiljöer. Här ingår många arter av fåglar, kärlväxter, spindeldjur, skalbaggar, fjärilar och groddjur. Havsstrandängar och sandiga miljöer är särskilt artrika. Havsstrandsarterna hotas främst av igenväxning, exploatering, mänsklig störning av häckningsplatser och livsmiljöer samt nedskräpning. De viktigaste åtgärderna är att återskapa blottade sandstränder och dyner, att säkerställa en välanpassad hävd av strandängar samt att minska föroreningar och marin nedskräpning.
|
|
| 3. |
- Sundberg, Sebastian, et al.
(författare)
-
Våtmarker
- 2015
-
Ingår i: Tillstånd och trender för arter och deras livsmiljöer - rödlistade arter i Sverige 2015. - 9789187853135 ; :17, s. 41-45
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Våtmarker, bl.a. myrar och sötvattensstränder, hyser totalt drygt 800 rödlistade arter, och för nästan 470 av dessa är våtmarkerna särskilt viktiga livsmiljöer. De flesta artgrupper har representanter här, men kärlväxter, lavar, tvåvingar och skalbaggar är särskilt artrika. Även mossor, fjärilar, fåglar och landmollusker är väl representerade. Rikkärr och sötvattensstränder är de artrikaste våtmarksmiljöerna. De rödlistade våtmarksarterna hotas främst av igenväxning, dikning, vattenreglering och eutrofiering. Restaurering, fortsatt och utökad hävd samt nyskapande av våtmarker är viktiga åtgärder, liksom återgång till naturlig vattenföring och vattenståndsdynamik i strandnära miljöer.
|
|
| 4. |
|
|
| 5. |
- Aronsson, Mora, et al.
(författare)
-
Ny validering av växter på gång
- 2017
-
Ingår i: Vår Fågelvärld. - 0042-2649. ; 2017, s. 20 - 21
-
Tidskriftsartikel (populärvet., debatt m.m.)
|
|
| 6. |
- Aronsson, Mora, et al.
(författare)
-
Sveriges arter och naturtyper i EU:s art- och habitatdirektiv : Resultat från rapportering 2019 till EU av bevarandestatus 2013-2018
- 2020
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Sverige har en variationsrik natur med storslagen fjällmiljö, myllrande våtmarker, vattendrag och sjöar, kust och hav, skogar och odlingslandskap, alla med ett rikt växt och djurliv. Den här fantastiska biologiska mångfalden tas ofta för given och ibland som en lyx, men oavsett vilket är det en förutsättning för vår överlevnad.2019 rapporterade Sverige statusen till EU för perioden 2013–2018 för de naturtyper och arter i Sverige som är listade i art- och habitatdirektivet. Den berättar att 20 procent av naturtyperna och 40 procent av arterna mår bra. Den biologiska mångfalden är hårt trängd i såväl Sverige som i andra EU-länder.Den här rapporten sammanfattar Sveriges rapportering och innehåller beskrivningar av status för naturtyper och arter, påverkan, hot och trender. Rapporten ger kunskap om tillståndet för den biologiska mångfalden i Sverige med hjälp av de arter och naturtyper som är listade i EU:s art- och habitatdirektiv.Rapporten visar hur naturmiljöerna i Sverige förändas, och sammanfattar den senaste kunskapen om vilka faktorer som driver dessa förändringar. Även exempel på hur vi genom restaurerings- och skötselåtgärder kan hejda förlusten av biologisk mångfald tas upp.
|
|
| 7. |
- Azzi, Elias Sebastian, et al.
(författare)
-
Assessing the diverse environmental effects of biochar systems : An evaluation framework
- 2021
-
Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 286
-
Tidskriftsartikel (refereegranskat)abstract
- Biochar has been recognised as a carbon dioxide removal (CDR) technology. Unlike other CDR technologies, biochar is expected to deliver various valuable effects in e.g. agriculture, animal husbandry, industrial processes, remediation activities and waste management. The diversity of biochar side effects to CDR makes the systematic environmental assessment of biochar projects challenging, and to date, there is no common framework for evaluating them. Our aim is to bridge the methodology gap for evaluating biochar systems from a life-cycle perspective. Using life cycle theory, actual biochar projects, and reviews of biochar research, we propose a general description of biochar systems, an overview of biochar effects, and an evaluation framework for biochar effects. The evaluation framework was applied to a case study, the Stockholm Biochar Project. In the framework, biochar effects are classified according to life cycle stage and life cycle effect type; and the biochar?s end-of-life and the reference situations are made explicit. Three types of effects are easily included in life cycle theory: changes in biosphere exchanges, technosphere inputs, and technosphere outputs. For other effects, analysing the cause-effect chain may be helpful. Several biochar effects in agroecosystems can be modelled as future productivity increases against a reference situation. In practice, the complexity of agroecosystems can be bypassed by using empirical models. Existing biochar life cycle studies are often limited to carbon footprint calculations and quantify a limited amount of biochar effects, mainly carbon sequestration, energy displacements and fertiliser-related emissions. The methodological development in this study can be of benefit to the biochar and CDR research communities, as well as decision-makers in biochar practice and policy.
|
|
| 8. |
- Azzi, Elias Sebastian, et al.
(författare)
-
Life cycle assessment of urban uses of biochar and case study in Uppsala, Sweden
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Biochar is a material derived from biomass pyrolysis that is used in urban applications. The environmental impacts of new biochar products has however not been assessed. Here, the life cycle assessments of 5 biochar products were performed for 7 biochar supply-chains in 2 energy contexts. The biochar products (tree planting, green roofs, landscaping soil, charcrete, and biofilm carrier) were benchmarked against reference products and the oxidative use of biochar for steel production. Biochar demand was then estimated using dynamic material flow analysis for a new city-district in Uppsala, Sweden. In a decarbonised energy system and if biochar stability is high, all biochar products had a better climate performance than the reference, and most applications outperformed biomass use for decarbonising steel production. The climate benefits of using biochar ranged from -1.4 to -0.11 tonne CO2-eq tonne-1 biochar in a decarbonised energy system. In other environmental impact categories, biochar products had either higher or lower impacts than the reference, depending on biochar supply-chains and materials substituted, with trade-offs between sectors and impact categories. This said, several use phase effects of biochar were not included in the assessment due to knowledge limitations. In Uppsala’s new district, biochar demand was around 1700 m3 year-1 during the 25 years of construction. By 2100, 23% of the biochar accumulated in landfills, raising questions for end-of-life management of biochar-containing products. Overall, in a post-fossil economy, biochar can be a carbon dioxide removal technology with benefits, but biochar applications must be designed to maximise co-benefits.
|
|
| 9. |
- Azzi, Elias Sebastian, et al.
(författare)
-
Life cycle assessment of urban uses of biochar and case study in Uppsala, Sweden
- 2022
-
Ingår i: Biochar. - : Springer Nature. - 2524-7972 .- 2524-7867. ; 4:1
-
Tidskriftsartikel (refereegranskat)abstract
- Biochar is a material derived from biomass pyrolysis that is used in urban applications. The environmental impacts of new biochar products have however not been assessed. Here, the life cycle assessments of 5 biochar products (tree planting, green roofs, landscaping soil, charcrete, and biofilm carrier) were performed for 7 biochar supply-chains in 2 energy contexts. The biochar products were benchmarked against reference products and oxidative use of biochar for steel production. Biochar demand was then estimated, using dynamic material flow analysis, for a new city district in Uppsala, Sweden. In a decarbonised energy system and with high biochar stability, all biochar products showed better climate performance than the reference products, and most applications outperformed biomass use for decarbonising steel production. The climate benefits of using biochar ranged from - 1.4 to - 0.11 tonne CO2-eq tonne(-1) biochar in a decarbonised energy system. In other environmental impact categories, biochar products had either higher or lower impacts than the reference products, depending on biochar supply chain and material substituted, with trade-offs between sectors and impact categories. However, several use-phase effects of biochar were not included in the assessment due to knowledge limitations. In Uppsala's new district, estimated biochar demand was around 1700 m(3) year(-1) during the 25 years of construction. By 2100, 23% of this biochar accumulated in landfill, raising questions about end-of-life management of biochar-containing products. Overall, in a post-fossil economy, biochar can be a carbon dioxide removal technology with benefits, but biochar applications must be designed to maximise co-benefits.
|
|
| 10. |
- Azzi, Elias Sebastian, et al.
(författare)
-
Prospective Life Cycle Assessment of Large-Scale Biochar Production and Use for Negative Emissions in Stockholm
- 2019
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 53:14, s. 8466-8476
-
Tidskriftsartikel (refereegranskat)abstract
- Several cities in Sweden are aiming for climate neutrality within a few decades and for negative emissions thereafter. Combined biochar, heat, and power production is an option to achieve carbon sequestration for cities relying on biomass-fuelled district heating, while biochar use could mitigate environmental pollution and greenhouse gas emissions from the agricultural sector. By using prospective life cycle assessment, the climate impact of the pyrolysis of woodchips in Stockholm is compared with two reference scenarios based on woodchip combustion. The pyrolysis of woodchips produces heat and power for the city of Stockholm, and biochar whose potential use as a feed and manure additive on Swedish dairy farms is explored. The climate change mitigation trade-off between bioenergy production and biochar carbon sequestration in Stockholm's context is dominated by the fate of marginal power. If decarbonisation of power is achieved, building a new pyrolysis plant becomes a better climate option than conventional combustion. Effects of cascading biochar use in animal husbandry are uncertain but could provide 10-20% more mitigation than direct biochar soil incorporation. These results help design regional biochar systems that combine negative carbon dioxide emissions with increased methane and nitrous oxide mitigation efforts and can also guide the development of minimum performance criteria for biochar products.
|
|
| 11. |
- Azzi, Elias Sebastian, et al.
(författare)
-
Small-scale biochar production on Swedish farms : A model for estimating potential, variability, and environmental performance
- 2021
-
Ingår i: Journal of Cleaner Production. - : Elsevier Ltd. - 0959-6526 .- 1879-1786. ; 280
-
Tidskriftsartikel (refereegranskat)abstract
- Several small-scale pyrolysis plants have been installed on Swedish farms and uptake is increasing in the Nordic countries. Pyrolysis plants convert biomass to biochar for agricultural applications and syngas for heating applications. These projects are driven by ambitions of achieving carbon dioxide removal, reducing environmental impacts, and improving farm finances and resilience. Before policy support for on-farm pyrolysis projects is implemented, a comprehensive environmental evaluation of these systems is needed. Here, a model was developed to jointly: (i) simulate operation of on-farm energy systems equipped with pyrolysis units; (ii) estimate biochar production potential and its variability under different energy demand situations and designs; and (iii) calculate life cycle environmental impacts. The model was applied to a case study farm in Sweden. The farm's heating system achieved net carbon dioxide removal through biochar carbon sequestration, but increased its impact in several other environmental categories, mainly due to increased biomass throughput. Proper dimensioning of heat-constrained systems is key to ensure optimal biochar production, as biochar production potential of the case farm was reduced under expected climate change in Sweden. To improve the environmental footprint of future biochar systems, it is crucial that expected co-benefits from biochar use in agriculture are realised. The model developed here is available for application to other cases.
|
|
| 12. |
- Berglund, Håkan, et al.
(författare)
-
Arters spridning i en grön infrastruktur : kunskapsöversikt och vägledning för analyser
- 2018
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Denna rapport innehåller fem kapitel som tillsammans ska bidra med vetenskapligt faktaunderlag och vägledning i olika frågor om arters spridning och spridningsmöjligheter – eller konnektivitet som det också kallas. I kapitel 1 ges en översikt av hur arbetet med grön infrastruktur kan organiseras och hur kunskap om arters spridning och konnektivitet kan vägas in i analyser. Kapitel 2 ger en introduktion till facktermer och matematiska modeller som används för att beskriva arters spridning och konnektivitet. Kapitel 3 och 4 innehåller kunskapsöversikter med fokus på forskningsstudier av djurs, växters och svampars spridning i skog samt i andra terrestra landskapstyper (gräsmarker, våtmarker och fjäll). I kapitel 5 översätts det som framkommit i kunskapsöversikterna till vägledning om när och hur spridning och konnektivitet bör vägas in i analyser av grön infrastruktur.
|
|
| 13. |
|
|
| 14. |
|
|
| 15. |
- Bjelke, Ulf, et al.
(författare)
-
Rödlistade arter och naturvård i sand- och grustäkter
- 2012
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Naturligt störningspräglade sandmarker hyser en artrik och konkurrenskänslig flora och fauna. Sådana livsmiljöer har minskat drastiskt under 1900-talet. Under samma period ökade antalet sand- och grustäkter. Trots att täkterna ofta innebär stora ingrepp i naturen kan de utgöra viktiga ersättningshabitat för arter knutna till sandiga miljöer. Sedan några decennier så minskar även sand- och grustäkter starkt, beroende på att samhället vill bevara naturliga sand- och grusresurser. Produktionen har medvetet flyttats till bergkrossanläggningar och det ges idag mycket få tillstånd för utökad verksamhet eller nya sandtäkter. Från fler än 5 000 aktiva täkter på 1990-talet har antalet sjunkit till färre än 1 000. Täkter som avslutas har ofta föreskrifter om att planas ut och övertäckas vilket gör att deras naturvärden spolieras. Drygt 300 rödlistade arter har gynnats av sandtäkter när ursprungshabitaten minskat. Steklar och skalbaggar utgör de största grupperna med närmare två tredjedelar av arterna. Södra Sverige hyser störst rikedom av dessa arter men såväl täkter som arternas mer naturliga miljöer är bristfälligt undersökta, särskilt i glest befolkade delar av landet. För att bevara dessa täktlevande arter krävs att naturvården arbetar för att förhindra att avslutade täkter planas ut eller täcks över. Det är av stor betydelse att naturvårdande myndigheter ges tillräckliga styrmedel och ekonomiska resurser att arbeta med täkter. Genom enkla åtgärder kan de skapade livsmiljöerna i täkter bevaras till en låg kostnad jämfört med andra alternativa biotopvårdande åtgärder. Rapporten belyser artsamhällena som kan finnas i täkter samt viktiga strategier och åtgärder för naturvård i dessa miljöer. Rapporten har finansierats av Naturvårdsverket och av SLU:s medel för fortlöpande miljöanalys.
|
|
| 16. |
|
|
| 17. |
- Campbell, Charles, 1982-
(författare)
-
Sphagnum limits : Physiology, morphology and climate
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Sphagnum is the most important plant genus in terms of terrestrial carbon cycling. It and the habitats it creates store an equivalent of ~68% of the CO2 in the atmosphere. The genus has little dispersal limitation and the mire habitats are functionally similar at global scales. Sphagnum species are limited by water deficit at local and biogeographic scales, but this alone is not sufficient to explain local and global scale species patterns. As Sphagnum shoots are long-lived they may be limited by stochastic periods of cold temperature. Within Europe, species are associated with climate gradients along north-south (cold-warm) and oceanic-continental (wet-dry) clines. Within mires, species are sorted along a moisture (hummock-hollow) gradient.In this thesis I examined species responses to and recovery from freezing (I). I compared species with different water level niches in traits related to water management of individual shoots and colonies (II). Using distribution modelling of GBIF data, I estimated how different aspects of climate contributed to Sphagnum species distributions in Europe (III). Combining the approaches in papers II and III, I modelled the climatic distributions of the parapatric species S. cuspidatum and S. lindbergii and assessed how traits of water economy varied across the distribution boundary (IV).Species responses to winter stress were largely allied to both their hydrological niche and geographic range. Generally, hollow species managed better than hummock species, but species from intermediate positions were less consistent in their response. Species associated with boreal regions were generally less affected than those from temperate regions. Hardening against low temperature was triggered by shorter days and cold nights. Cold temperatures during late autumn may be more important for Sphagnum limits than the minimum temperature during winter.Water-related traits split the species into two groups; hollows species with large capitula and hummock species with small capitula. However, inter- and intra-specific trait variation and trait trends along the hydrological gradient were not necessarily the same at the shoot and canopy scale. Some trait correlations were common to all species. Canopy traits, which were emergent traits of colonies of shoots, had the strongest trait associations with the species position along the hummock-hollow gradient.At the continental scale the distribution of most Sphagnum species could be successfully modelled by a combination of annual degree days and water balance and the degree of seasonality in these two variables. Individual species distributions were shaped more by the seasonality in degree days than in water balance.Across the distributional border of S. cuspidatum and S. lindbergii divergence in the measured traits was mostly seen in the capitula indicating that limits to Sphagnum species are strongly linked to the functioning of the capitulum. Capitulum mass of both species was lower in sympatry than in allopatry, even though the measured values were similar. Canopy traits most strongly separated the species though did not change across the species boundaries.In summary, Sphagnum species in general are limited by the availability of water. Low temperature, particularly during late autumn are probably decisive for the biogeographic limits and for the distribution of species along the hydrological gradient.
|
|
| 18. |
- Echternach, Matthias, et al.
(författare)
-
High-Speed Imaging and Electroglottography Measurements of the Open Quotient in Untrained Male Voices' Register Transitions
- 2010
-
Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 24:6, s. 644-650
-
Tidskriftsartikel (refereegranskat)abstract
- Vocal fold oscillation patterns in vocal register transitions are still unclarified. The vocal fold oscillations and the open quotient were analyzed with high-speed digital imaging (HSDI) and electroglottography (EGG) in 18 male untrained subjects singing a glissando from modal to the falsetto register. Results reveal that the open quotient changed with register in both HSDI. and EGG. The in-class correlations for different HSDI and EGG determinations of the open quotient were high. However, we found only weak interclass correlations between both methods. In ID subjects, irregularities of vocal fold vibration occurred during the register transition. Our results confirm previous observations that falsetto register is associated with a higher open quotient compared with modal register. These data suggest furthermore that irregularities typically observed in audio and electroglottographic signals during register transitions are caused by irregularities in vocal fold vibration.
|
|
| 19. |
- Fan, B.-B., et al.
(författare)
-
Dry/wet cycling reduces spore germination and viability in six peatland bryophytes
- 2023
-
Ingår i: Plant Biology. - : German Society for Plant Sciences; Royal Botanical Society of the Netherlands. - 1435-8603 .- 1438-8677. ; 25:3, s. 440-447
-
Tidskriftsartikel (refereegranskat)abstract
- Dry/wet cycling driven by water level fluctuation in wetlands may strongly influence the destiny of seeds. However, how dry/wet cycling affects spore survival and germinability in peatland bryophytes is poorly understood.Six peatland bryophytes, three hummock- and three hollow-dwelling Sphagnum species, were chosen as study species. We tested the effects of dry (60% air RH)/wet (waterlogging) cycle frequency (once per 12, 8 or 4 days for low, medium or high, respectively) and ratio (3:1, 1:1 or 1:3 dry:wet time per cycle) on spore germinability, viability, dormancy percentage and protonema development.Dry/wet cycling significantly reduced spore germination percentage and viability and slowed protonema development in all Sphagnum species, being more pronounced with higher dry/wet cycling frequencies. The hummock species S. capillifolium and S. fuscum had higher spore germination percentage after the continuous dry treatment, while the hollow species S. angustifolium, S. squarrosum and S. subsecundum showed the opposite response, compared to the continuously wet treatment. Except for S. squarrosum, spore viability was higher after the dry than after the wet treatment. Spore viability and dormancy percentage were higher after a dry/wet ratio of 1:3 than after ratios of 3:1 and 1:1.Our study shows that both germinability and viability of bryophyte spores are reduced by dry/wet cycling (especially when frequent) in peatlands. This emphasizes the need to ensure constant water levels and low frequencies of water level fluctuation, which are relevant in connection with wetland restoration, to promote Sphagnum spore survival and establishment in peatlands after disturbances.
|
|
| 20. |
|
|
| 21. |
- Hedberg, Petter, et al.
(författare)
-
A functional trait approach to fen restoration analysis
- 2013
-
Ingår i: Applied Vegetation Science. - : Wiley. - 1402-2001 .- 1654-109X. ; 16:4, s. 658-666
-
Tidskriftsartikel (refereegranskat)abstract
- Questions: Ecological restoration has traditionally been evaluated with analyses focused on species identities and abundances. These analyses provide no ecological explanation to why certain species change in abundance. One solution may be a functional trait analysis. We asked whether shifts in functional traits could explain vegetation changes in fens restored through tree cutting and rewetting, and how the functional traits in the restored sites compare to those of the reference site? Location: Three former rich fens in east-central Sweden. Methods: Tree cutting and rewetting were applied in a factorial design, and species and abundance data were recorded for 8yrs. Abundance data and trait data of canopy height, specific leaf area (SLA) and diaspore mass were used to calculate functional richness (FRic), functional divergence (FDiv), functional dispersion (FDis) and community-weighted mean (CWM) of functional traits. Data were analysed in a linear mixed effect model for vascular plants and bryophytes jointly, and for vascular plants separately. Results of restoration treatments were compared to data from a reference site. Results: Among vascular plants, tree cutting caused a decrease in SLA, as shade-sensitive species increased. In accordance with the change in SLA, FDis increased. In the joint analysis, tree cutting led to increased FDis, FDiv and FRic, indicating reduced filtering caused by the removal of the shading canopy, which allowed shade-sensitive species to establish. The comparison to the reference site shows that even after 8yrs, the restoration treatments have higher trait diversity than the reference site, indicating that the restoration sites have a too relaxed trait filter compared to conditions in an undisturbed fen. Our interpretation is that this is primarily caused by insufficient rewetting (and increased nutrient availability) that allow species of both natural and degraded fen conditions to co-exist, and which failed to suppress the regrowth of trees. Conclusions: Analysis of functional diversity improves our understanding of the ecological mechanisms affecting restoration results, and allows comparison among regions and communities with different species composition.
|
|
| 22. |
- Hedberg, Petter, et al.
(författare)
-
Vegetation recovery after multiple-site experimental fen restorations
- 2012
-
Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 147:1, s. 60-67
-
Tidskriftsartikel (refereegranskat)abstract
- Large peatland areas have been drained for forestry and agricultural purposes, resulting in the decline of characteristic biodiversity. Two measures commonly suggested for restoring drained fens is ditch blocking and tree removal to raise the groundwater table and increase light availability, respectively. In 2002, we initiated factorial restoration experiments, including ditch blocking and tree removal, in three former rich fens that had been drained for forestry purposes. Species cover of vascular plants and bryophytes were monitored during 8 years in permanent plots along transects perpendicular to the ditch for all four treatment combinations. Both methods had positive and independent effects on the cover of wetland vegetation. Specifically, Sphagnum species and wetland bryophytes showed a persistent positive response to both clear cutting and rewetting. Wetland vascular plants and grasses showed a persistent positive response to clear cutting. Sedges and species number responded positively to both clear cutting and ditch blocking, but the response was partly transient, and for species richness the response was limited when restoration methods were applied separately. Rich fen indicators of vascular plants and bryophytes did not respond to any of the restoration treatments. This indicates that species introduction in combination with further habitat restorations may be necessary to re-establish the original rich fen flora. Nevertheless, we conclude that the combination of ditch blocking and clear cutting are effective measures to partly restore wetland vegetation on previously drained and forested fens, while peat subsidence along the ditch may restrict the success further away from ditches.
|
|
| 23. |
- Jacobson, Anders, et al.
(författare)
-
Upplands botaniska utflyktsguide
- 2020
-
Ingår i: Daphne. - 1101-5527. ; 31, s. 23-26
-
Tidskriftsartikel (populärvet., debatt m.m.)
|
|
| 24. |
|
|
| 25. |
- Johansson, Victor, et al.
(författare)
-
Air humidity thresholds trigger active moss spore release to extend dispersal in space and time
- 2016
-
Ingår i: Functional Ecology. - : Wiley. - 0269-8463 .- 1365-2435. ; 30:7, s. 1196-1204
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding the complete dispersal process is important for making realistic predictions of species distributions, but mechanisms for diaspore release in wind-dispersed species are often unknown. However, diaspore release under conditions that increase the probability of longer dispersal distances and mechanisms that extend dispersal events in time may have evolutionary advantages. We quantified air humidity thresholds regulating spore release in the moss Brachythecium rutabulum. We also investigated the prevailing micrometeorological conditions when these thresholds occur in nature and how they affect dispersal distances up to 100m, using a mechanistic dispersal model. We show that moss spores were mainly released when the peristome teeth were opening, as relative air humidity (RH) decreased from high values to relatively low (mainly between 90% and 75% RH). This most often occurred in the morning, when wind speeds were relatively low. Surprisingly, the model predicted that an equally high proportion of the spores would travel distances beyond 100m (horizontally) when released in the wind conditions prevailing during events of RH decrease in the morning, that lead to peristome opening, as in the highest wind speeds. Moreover, a higher proportion of the spores reached high altitudes when released at the lower wind speeds during the morning compared to the higher speeds later in the day, indicating a possibility for extended dispersal distances when released in the morning. Dispersal in the morning is enhanced by a combination of a more unstable atmospheric surface layer that promotes vertical dispersal, and a lower wind speed that decreases the spore deposition probability onto the ground, compared to later in the day. Our study demonstrates an active spore release mechanism in response to diurnally changing air humidity. The mechanism may promote longer dispersal distances, because of enhanced vertical dispersal and because spores being released in the morning have more time to travel before the wind calms down at night. The mechanism also leads to a prolonged dispersal period over the season, which may be viewed as a risk spreading in time that ultimately also leads to a higher diversity of establishment conditions, dispersal distances and directions.
|
|
