Au Québec depuis mai 2005, Saloumeh Momenipour est venue d'Iran pour compléter une maîtrise en sciences de l'environnement sous la direction d'Annie Desrochers et de Francine Tremblay. Ses travaux portent comparaison de la structure génétique et physiologique de la régénération du peuplier faux-tremble après feu et après coupe en association avec l'épinette noire.
Comparaison de la structure génétique et physiologique du peuplier faux-tremble présent dans des peuplements d'épinette noire après feu et après récolte forestière
Trembling aspen (Populus tremuloïdes Michx.) is a pioneer tree species in the Canadian boreal forest that regenerates after disturbance by suckering, from belowground roots, and can rapidly develop a closed canopy.
In absence of large disturbances the even-aged post-fire aspen cohort could either be self-maintained in canopy gaps or replaced by more shade tolerant coniferous species. In the southern part of the boreal forest, the invasion of boreal coniferous forests by broadleaves species after cutting has been observed. Competition by aspen early after disturbance can significantly reduce conifer recruitment and growth. In this project we try to understand the mechanisms of aspen regeneration following either harvesting or wildfire disturbances.
Disturbance types can influence forest natural dynamics and contribute to increase the proportion of aspen in spruce dominated forests at the landscape level. Our hypothesis are the following: 1) the principal mode of invasion of aspen in the harvested black spruce forest is by root suckering, originating from aspen trees already present in the harvested stand, while after fire we could have both seedlings and suckers, 2) higher level of disturbance increases the proportion of aspen irrelative to black spruce within a stand ,3) burned spruce forests should be occupied by many aspen clones of small size, while harvested black spruce forests should be occupied by a small number of aspen clones of larger size, 4) aspen trees growing from suckers are more vigorous than those from seedlings origin. This study will be conducted in the boreal forest of northwestern Québec. The invasion of black spruce forests by aspen will be characterized in young stands originating from natural (fire) and anthropogenic (cutting) disturbances. The regeneration mode and clonal structure of aspen will be studied by looking at root connection and DNA markers. The vigor of the seedling/suckers will be compared with gas exchanges (photosynthesis) and energy reserves.
Saloumeh Momenipour. Aspen Dynamics after harvesting in boreal coniferous forest of northwestern Quebec. 2013. Mémoire de maîtrise en biologie, Université du Québec en Abitibi-Témiscamingue. 78 p.
Saloumeh Momenipour The impact of harvesting intensity on aspen recruitment and genetic structure in a coniferous stands
Séminaire maîtrise (2012-05-16)