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To explain the transition between the southern mixedwood and the northern coniferous bioclimatic domains that are dominated, respectively, by balsam fir (Abies balsamea (L.)Mill.) and black spruce (Picea mariana (Mill.) B.S.P.), 59 sites were selected throughout the two bioclimatic domains. The regeneration (seedling abundance) and mortality (difference between seedlings and saplings) of balsam fir seedlings were compared within and between bioclimatic domains. We also determined the soil types (clay and till), summer growing degree-days above 5[degrees]C (GDD_5), and total summer precipitation (PP_MA). Balsam fir regeneration was strongly linked to parental trees and was higher in the mixedwood bioclimatic domain than in the coniferous domain, with higher regeneration occurring on till than on clay soils. Mortality was higher on till than on clay soils due to competition between balsam fir seedlings, with other species having either no effect or decreasing mortality. Unlike PP_MA, GDD_5 positively influenced balsam fir regeneration. The dynamics of balsam fir stands in the coniferous bioclimatic domain were attributed to a decrease in balsam fir regeneration and to an increase in its mortality, most likely due to a lack of suitable establishment substrates (till soils) and cooler temperatures. Small balsam fir populations still persist in the northernmost latitudes of the species' range, mainly where parental trees occur on good establishment substrates. Our study contributes to a better understanding of the effect of species, climate, and site condition on latitudinal vegetation dynamics at a global scale. Key words: balsam fir, seedlings, coniferous domain, mixedwood domain, climate change. Pour expliquer la transition entre les domaines bioclimatiques des forets mixtes du sud et des forets resineuses du nord, qui sont respectivement dominees par le sapin baumier (Abies balsamea (L.) Mill.) et l'epinette noire (Picea mariana (Mill.) B.S.P.), 59 stations ont ete selectionnees dans les deux domaines bioclimatiques. La regeneration (abondance des semis) et la mortalite (difference entre le nombre de semis et de gaules) des semis de sapin baumier ont ete compares dans chacun des domaines bioclimatiques et entre eux. Nous avons aussi determine le type de sol (argile et till), les degres-jours de croissance au-dessus de 5[degrees]C pendant l'ete (DJC_5) et les precipitations estivales totales (PP_MA). La regeneration en sapin baumier etait fortement liee aux arbres parentaux et etait plus elevee dans le domaine bioclimatique des forets mixtes que dans celui des forets resineuses, avec des valeurs plus elevees sur les tills que sur les sols argileux. La mortalite etait plus forte sur les tills que sur les sols argileux a cause de la competition entre les semis de sapin baumier, alors que la mortalite des autres especes n'etait pas influencee ou diminuait. Contrairement aux PP_MA, les DJC_5 influencaient positivement la regeneration en sapin baumier. La dynamique des peuplements de sapin baumier dans le domaine bioclimatique des forets resineuses a ete attribuee a une diminution de la regeneration en sapin baumier et a une augmentation de sa mortalite, qui ont probablement ete causees par un manque de substrats d'etablissement approprie (tills) et des temperatures plus froides. De petites populations de sapin baumier sont toujours presentes sous les latitudes les plus nordiques de son aire de distribution, surtout aux endroits ou les arbres parentaux sont presents sur de bons substrats d'etablissement. Notre etude contribue a une meilleure comprehension des effets de l'espece, du climat et des conditions des stations sur la dynamique latitudinale de la vegetation a l'echelle globale. [Traduit par la Redaction] Mots-cles : sapin baumier, semis, domaine des forets resineuses, domaine des forets mixtes, changements climatiques., Introduction Tree population dynamics are closely related to seed availability and recruitment potential, which may be limited by many factors (Clark et al. 1998). Tree seedlings, which constitute the first [...]

It is important to understand price premiums related to certified raw wood to predict the future of forest certifications from the perspective of forestry enterprises. We focused on identifying the trading roundwood market data in the economic center of power in Tokyo. This study aimed to clarify Tama-certified raw wood prices under the local area certification scheme, forest-certified raw wood prices, and the handling volumes at the Tama Roundwood Market Center in Tokyo. Sales details of the Tama Roundwood Market Center were used to identify the handling volumes, Tama-certified raw wood prices, and FSC (Forest Stewardship Council) or SGEC (Japan-specific Sustainable Green Ecosystem Council)-certified raw wood prices. The FSC and SGEC have operated from the center since 2016. Data were collected from the 2006–2018 fiscal years. Our results showed that the volume of raw wood handled increased due to the regeneration-cutting project conducted by the Tokyo Metropolitan Government. On the other hand, there was no price premium for Tama-certified raw wood under the local certification scheme or for FSC- or SGEC-certified raw wood. Price premiums for forest certifications are necessary for ongoing sustainable forest management. There is a need to increase consumer awareness of forest certifications and to differentiate quality certifications further, and these would likely create price premiums. [ABSTRACT FROM AUTHOR]