Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Bergeron Yves) "

Sökning: WFRF:(Bergeron Yves)

  • Resultat 1-5 av 5
Sortera/gruppera träfflistan
  • Abbott, Benjamin W., et al. (författare)
  • Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire : an expert assessment
  • 2016
  • Ingår i: Environmental Research Letters. - : IOP Publishing: Open Access Journals / IOP Publishing. - 1748-9326 .- 1748-9326. ; 11:3
  • Tidskriftsartikel (refereegranskat)abstract
    • As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are unlikely in the near future, so to address this gap, we present estimates from 98 permafrost-region experts of the response of biomass, wildfire, and hydrologic carbon flux to climate change. Results suggest that contrary to model projections, total permafrost-region biomass could decrease due to water stress and disturbance, factors that are not adequately incorporated in current models. Assessments indicate that end-of-the-century organic carbon release from Arctic rivers and collapsing coastlines could increase by 75% while carbon loss via burning could increase four-fold. Experts identified water balance, shifts in vegetation community, and permafrost degradation as the key sources of uncertainty in predicting future system response. In combination with previous findings, results suggest the permafrost region will become a carbon source to the atmosphere by 2100 regardless of warming scenario but that 65%-85% of permafrost carbon release can still be avoided if human emissions are actively reduced.
  • Chagtai, Tasnim, et al. (författare)
  • Gain of 1q as a prognostic biomarker in Wilms Tumors (WTs) treated with preoperative chemotherapy in the International Society of Paediatric Oncology (SIOP) WT 2001 trial : A SIOP renal tumours biology consortium study
  • Ingår i: Journal of Clinical Oncology. - : American Society of Clinical Oncology. - 0732-183X. ; 34:26, s. 3195-3203
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Wilms tumor (WT) is the most common pediatric renal tumor. Treatment planning under International Society of Paediatric Oncology (SIOP) protocols is based on staging and histologic assessment of response to preoperative chemotherapy. Despite high overall survival (OS), many relapses occur in patients without specific risk factors, and many successfully treated patients are exposed to treatments with significant risks of late effects. To investigate whether molecular biomarkers could improve risk stratification, we assessed 1q status and other potential copy number biomarkers in a large WT series. Materials and Methods: WT nephrectomy samples from 586 SIOP WT 2001 patients were analyzed using a multiplex ligation-dependent probe amplification (MLPA) assay that measured the copy number of 1q and other regions of interest. Results: One hundred sixty-seven (28%) of 586 WTs had 1q gain. Five-year event-free survival (EFS) was 75.0% in patients with 1q gain (95% CI, 68.5% to 82.0%) and 88.2% in patients without gain (95% CI, 85.0% to 91.4%). OS was 88.4% with gain (95% CI, 83.5% to 93.6%) and 94.4% without gain (95% CI, 92.1% to 96.7%). In univariable analysis, 1q gain was associated with poorer EFS (P < .001; hazard ratio, 2.33) and OS (P = .01; hazard ratio, 2.16). The association of 1q gain with poorer EFS retained significance in multivariable analysis adjusted for 1p and 16q loss, sex, stage, age, and histologic risk group. Gain of 1q remained associated with poorer EFS in tumor subsets limited to either intermediate-risk localized disease or nonanaplastic localized disease. Other notable aberrations associated with poorer EFS included MYCN gain and TP53 loss. Conclusion: Gain of 1q is a potentially valuable prognostic biomarker in WT, in addition to histologic response to preoperative chemotherapy and tumor stage.
  • Drobyshev, Igor, et al. (författare)
  • Atlantic SSTs control regime shifts in forest fire activity of Northern Scandinavia
  • 2016
  • Ingår i: ; 6
  • Tidskriftsartikel (refereegranskat)abstract
    • Understanding the drivers of the boreal forest fire activity is challenging due to the complexity of the interactions driving fire regimes. We analyzed drivers of forest fire activity in Northern Scandinavia (above 60 N) by combining modern and proxy data over the Holocene. The results suggest that the cold climate in northern Scandinavia was generally characterized by dry conditions favourable to periods of regionally increased fire activity. We propose that the cold conditions over the northern North Atlantic, associated with low SSTs, expansion of sea ice cover, and the southward shift in the position of the subpolar gyre, redirect southward the precipitation over Scandinavia, associated with the westerlies. This dynamics strengthens high pressure systems over Scandinavia and results in increased regional fire activity. Our study reveals a previously undocumented teleconnection between large scale climate and ocean dynamics over the North Atlantic and regional boreal forest fire activity in Northern Scandinavia. Consistency of the pattern observed annually through millennium scales suggests that a strong link between Atlantic SST and fire activity on multiple temporal scales over the entire Holocene is relevant for understanding future fire activity across the European boreal zone.
  • Drobyshev, Igor, et al. (författare)
  • Multi-century reconstruction of fire activity in Northern European boreal forest suggests differences in regional fire regimes and their sensitivity to climate
  • 2014
  • Ingår i: Journal of Ecology. - : Wiley-Blackwell. - 0022-0477 .- 1365-2745. ; 102:3, s. 738-748
  • Tidskriftsartikel (refereegranskat)abstract
    • Forest fires are one of the main disturbance agents in boreal and temperate ecosystems. To decipher large-scale temporal and spatial patterns of past fire activity in Scandinavia, we analysed the synchronicity of dendrochoronologically reconstructed fire events in a large network of sites (n=62; 3296 samples, 392 individual fire years) covering a wide geographical gradient (56.5-67.0 degrees N and 9.3-20.5 degrees E) over AD 1400-1900. We identified large fire years (LFY) as years with regionally increased forest fire activity and located the geographical centres of climatic anomalies associated with synchronous LFY occurrence across the region, termed LFY centroids. The spatial pattern of LFY centroids indicated the presence of two regions with climatically mediated synchronicity of fire occurrence, located south and north from 60 degrees N. The return intervals of LFYs in Scandinavia followed a Weibull distribution in both regions. Intervals, however, differed: a period of 40years would carry a 0.93 probability of LFY occurrence in the southern region, but only a 0.48 probability of LFY occurrence in the northern region. Over 1420-1759, the northern region was characterized by significantly higher temporal variability in LFY occurrence than the southern region. Temporal correlation of LFYs with reconstructed average summer temperature and total precipitation was evident mainly for the northern region. LFYs in this region were associated with positive temperature and negative precipitation anomalies over Scandinavia and with colder and wetter conditions in more southern parts of the European subcontinent. Synthesis. Historical patterns of the occurrence of large fire years (LFY) in Scandinavia point towards the presence of two well-defined zones with characteristic fire activity, with the geographical division at approximately 60 degrees N. The northern and mid-boreal forests, although exhibiting lower LFY frequencies, appeared to be more sensitive to past summer climate, as compared to the southern boreal forests. This would imply that fire regimes across Scandinavia may show an asynchronous response to future climate changes.
  • Harper, Karen A., et al. (författare)
  • Edge influence on vegetation at natural and anthropogenic edges of boreal forests in Canada and Fennoscandia
  • 2015
  • Ingår i: Journal of Ecology. - 0022-0477 .- 1365-2745. ; 103:3, s. 550-562
  • Tidskriftsartikel (refereegranskat)abstract
    • Although anthropogenic edges are an important consequence of timber harvesting, edges due to natural disturbances or landscape heterogeneity are also common. Forest edges have been well studied in temperate and tropical forests, but less so in less productive, disturbance-adapted boreal forests. We synthesized data on forest vegetation at edges of boreal forests and compared edge influence among edge types (fire, cut, lake/wetland; old vs. young), forest types (broadleaf vs. coniferous) and geographic regions. Our objectives were to quantify vegetation responses at edges of all types and to compare the strength and extent of edge influence among different types of edges and forests. Research was conducted using the same general sampling design in Alberta, Ontario and Quebec in Canada, and in Sweden and Finland. We conducted a meta-analysis for a variety of response variables including forest structure, deadwood abundance, regeneration, understorey abundance and diversity, and non-vascular plant cover. We also determined the magnitude and distance of edge influence (DEI) using randomization tests. Some edge responses (lower tree basal area, tree canopy and bryophyte cover; more logs; higher regeneration) were significant overall across studies. Edge influence on ground vegetation in boreal forests was generally weak, not very extensive (DEI usually <20m) and decreased with time. We found more extensive edge influence at natural edges, at younger edges and in broadleaf forests. The comparison among regions revealed weaker edge influence in Fennoscandian forests.Synthesis. Edges created by forest harvesting do not appear to have as strong, extensive or persistent influence on vegetation in boreal as in tropical or temperate forested ecosystems. We attribute this apparent resistance to shorter canopy heights, inherent heterogeneity in boreal forests and their adaptation to frequent natural disturbance. Nevertheless, notable differences between forest structure responses to natural (fire) and anthropogenic (cut) edges raise concerns about biodiversity implications of extensive creation of anthropogenic edges. By highlighting universal responses to edge influence in boreal forests that are significant irrespective of edge or forest type, and those which vary by edge type, we provide a context for the conservation of boreal forests.
Skapa referenser, mejla, bekava och länka
  • Resultat 1-5 av 5
Typ av publikation
tidskriftsartikel (5)
Typ av innehåll
refereegranskat (5)
Bergeron, Yves (4)
Hylander, Kristoffer (1)
Abbott, Benjamin W. (1)
Jones, Jeremy B. (1)
Schuur, Edward A. G. (1)
Chapin, F. Stuart, I ... (1)
visa fler...
Bowden, William B. (1)
Bret-Harte, M. Syndo ... (1)
Epstein, Howard E. (1)
Flannigan, Michael D ... (1)
Harms, Tamara K. (1)
Hollingsworth, Teres ... (1)
Mack, Michelle C. (1)
McGuire, A. David (1)
Natali, Susan M. (1)
Rocha, Adrian V. (1)
Tank, Suzanne E. (1)
Turetsky, Merritt R. (1)
Vonk, Jorien E. (1)
Wickland, Kimberly P ... (1)
Aiken, George R. (1)
Alexander, Heather D ... (1)
Amon, Rainer M. W. (1)
Benscoter, Brian W. (1)
Bishop, Kevin (1)
Blarquez, Olivier (1)
Bond-Lamberty, Ben (1)
Breen, Amy L. (1)
Buffam, Ishi (1)
Cai, Yihua (1)
Carcaillet, Christop ... (1)
Carey, Sean K. (1)
Chen, Jing M. (1)
Chen, Han Y. H. (1)
Christensen, Torben ... (1)
Cooper, Lee W. (1)
Cornelissen, J. Hans ... (1)
de Groot, William J. (1)
DeLuca, Thomas H. (1)
Dorrepaal, Ellen (1)
Fetcher, Ned (1)
Finlay, Jacques C. (1)
Forbes, Bruce C. (1)
French, Nancy H. F. (1)
Gauthier, Sylvie (1)
Girardin, Martin P. (1)
Goetz, Scott J. (1)
Goldammer, Johann G. (1)
Gough, Laura (1)
Grogan, Paul (1)
visa färre...
Stockholms universitet (3)
Lunds universitet (2)
Göteborgs universitet (1)
Umeå universitet (1)
Mittuniversitetet (1)
Sveriges Lantbruksuniversitet (1)
Engelska (5)
Forskningsämne (UKÄ/SCB)
Naturvetenskap (4)
Medicin och hälsovetenskap (1)
Lantbruksvetenskap (1)


pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy