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Concerns about climate change and the desire to develop a domestic, renewable energy source are increasing the interest in forest biomass extraction, especially in the form of logging residues, i.e., tree tops and branches. We reviewed the literature to determine the site and soil conditions under which removal of logging residues along with the stem (i.e., whole-tree harvesting), especially at clearcut, results in negative impacts on soil productivity compared with conventional stem-only harvesting in boreal and temperate forests. Negative impacts of biomass harvesting on soil nutrient pools (e.g., nitrogen, phosphorus and base cations) and soil acid-base status are more frequent in the forest floor than in the mineral soil. In the first years post-harvest, however, biomass harvesting has the greatest potential to influence tree survival and growth, either positively or negatively, through its effects on microclimate and competing vegetation. Later in the rotation, impaired nitrogen and (or) phosphorus nutrition on whole-tree harvested sites has been shown to reduce tree growth for at least 20 years in some stands. Biomass removal can also reduce the concentrations of base cations in soils and foliage, but this has not, to date, been shown to affect tree productivity. There are no consistent, unequivocal and universal effects of forest biomass harvesting on soil productivity. However, climate and microclimate, mineral soil texture and organic C content, the capacity of the soil to provide base cations and phosphorus, and tree species autecology appear to be critical determinants of site sensitivity to biomass harvesting. Rigorous, long-term experiments that follow stand development through a rotation will facilitate the identification of categories of site or stand conditions under which negative impacts of biomass harvesting are likely. Key words: forest biomass, whole-tree harvesting, soil productivity, tree nutrition, stand productivity. Les preoccupations au sujet des changements climatiques et la volonte de developper des sources d'energie domestique renouvelable augmentent l'interet pour l'extraction de la biomasse forestiere, surtout sous la forme de residus de coupe, c.-a-d., les cimes et les branches des arbres. Les auteurs ont conduit une revue de litterature pour determiner les conditions de site et de sol pour lesquelles l'enlevement des residus de coupe en plus de la tige (c.-a-d., la coupe par arbre entier ), surtout lors de coupes a blanc, conduit a des impacts negatifs sur la productivite des sols comparativement a la recolte conventionnelle du tronc seulement, en forets boreales et temperees. Les impacts negatifs de la recolte de la biomasse sur les reserves du sol en nutriments (p. ex. azote, phosphore et cations basiques) et sur le statut acidite-alcalinite apparaissent plus frequents dans l'humus que dans le sol mineral. Cependant, au cours des premieres annees suivant la recolte, le prelevement de la biomasse montre le plus fort potentiel pour influencer la survie des arbres et leur croissance, soit positivement soit negativement, par ses effets sur le microclimat et la vegetation competitrice. Plus tard dans la revolution, on observe que pour certains peuplements, une nutrition amoindrie en azote et (ou) phosphore sur les sites avec coupe par arbre entier reduit la croissance des arbres pendant au moins 20 ans. Le prelevement de la biomasse peut egalement reduire les teneurs en cations basiques dans les sols et le feuillage, mais ceci ne semble pas se traduire en effet sur la productivite. Il n'y a pas d'effets non equivoques et universels de la recolte de la biomasse sur la productivite des sols. Cependant, le climat et le microclimat, la granulometrie du sol, sa teneur en C organique, sa capacite a fournir les cations basiques et le phosphore, ainsi que l'autecologie des especes semblent constituer des determinants importants de la sensibilite des sites a la recolte de la biomasse. Des experiences rigoureuses, conduites a long terme pour suivre le developpement des peuplements tout au long de la revolution, faciliteront l'identification des categories de sites ou les conditions des peuplements pour lesquels des impacts negatifs sont susceptibles de se developper. [Traduit par la Redaction], Introduction Biomass from forests and byproducts from the manufacturing of traditional forest products are increasingly used to generate a range of bioproducts, of which bioenergy is currently the most common. [...]

Industrial emissions in the Athabasca Oil Sands Region (AOSR), Alberta, Canada, have caused concerns about the effect of oil sands operations on the surrounding terrestrial environments, including jack pine (Pinus banksiana Lamb.) stands. We collected jack pine needles from 19 sites in the AOSR (13-128 km from main operations) for foliar chemical analyses to investigate the environmental impact on jack pine. Pine needles from three age classes, the current annual growth (CAG, 2011), one year and two year old pine needles, were collected. Samples were analyzed for total carbon (TC), nitrogen (TN), and sulfur (TS), inorganic S (SO4-S), base cations (Ca, Mg, Na), and other elements (B, Cu, Fe, Mn, P, Zn); CAG needles were also analyzed for their nitrogen and carbon isotopic compositions. Only TN, TS, Ca, B, Zn, and Fe contents showed weak but significant increases with proximity to the major oil sands operations. C and N isotopic compositions showed no trend with distance or TC and TN contents. Total S contents in CAG of pine foliage increased significantly with proximity to the main industrial operation while foliar inorganic S to organic S ratios (SO4-S/Sorg) ranged consistently between 0.13 and 0.32, indicating low to moderately high S loading. Hence, this study suggests some evidence of uptake of S emissions in close proximity to anthropogenic sources, although the reported values have not reached a level of environmental concern. [ABSTRACT FROM AUTHOR]