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Seismic lines are prominent linear disturbances across boreal Canada with large-scale consequences to wildlife and ecosystem function. Although seismic line restoration has been observed to improve tree growth and survival, application in peatlands has been shown to alter ecosystem functions such as hydrology and carbon storage. The most common active restoration method is called mechanical mounding, where the classic technique inverts the peat profile. New mounding methods that maintain the peat profile may provide benefits by preserving existing vegetation and reducing disturbance. To determine the effects of different mounding methods on soil quality, we collected and analyzed peat cores from two different sites for various soil properties (C/N ratios, [delta][sup.13]C, [delta][sup.15]N, and Fourier transform infrared (FTIR) spectroscopy humification indices). Vegetation surveys were also conducted. The two sites are both a collection of seismic lines crossing poor fens in Alberta. One site was treated with the classic method, while the other was treated with two new mounding methods. Classic mechanical mounding significantly increased the degree of decomposition, indicative of lower substrate quality. Mechanical mounding also greatly reduced moss cover and introduced large amounts of bare ground cover. The two newer mounding methods did not result in these changes and were largely comparable to natural peat properties and vegetation communities. Preserving the peat profile in new mounding methods may support faster return of ecosystem function. Key words: organic soil, bulk density, mechanical mounding, C/N ratio, stable isotopes Les lignes sismiques sont des perturbations lineaires importantes dans la region boreale du Canada qui ont des consequences a grande echelle sur la faune et la fonction des ecosystemes. Meme si on a observe que la restauration des lignes sismiques ameliore la croissance et la survie des arbres, on a demontre que son application dans les tourbieres modifie les fonctions de l'ecosysteme telles que l'hydrologie et le stockage du carbone. La methode de restauration active la plus courante s'appelle le buttage mecanique oU la technique classique inverse le profil de la tourbe. De nouvelles methodes de buttage qui maintiennent le profil de la tourbe peuvent presenter des avantages en preservant la vegetation existante et en reduisant les perturbations. Pour determiner les effets de differentes methodes de buttage sur la qualite du sol, on a preleve et analyse des carottes de tourbe sur deux sites differents pour confirmer diverses proprietes du sol (rapport C/N, [delta][sup.13]C, [delta][sup.15]N, indices d'humification par spectroscopie infrarouge a transformee de Fourier (FTIR)). Des etudes de la vegetation ont egalement ete menees. Les deux sites correspondent a un ensemble de lignes sismiques traversant des tourbieres pauvres en Alberta. La methode classique a ete utilisee pour traiter un site tandis que l'autre a ete traite avec deux nouvelles methodes de buttage. Le buttage mecanique classique a augmente de maniere significative le degre de decomposition, ce qui indique une qualite inferieure du substrat. Le buttage mecanique a egalement reduit considerablement la couverture de mousse et a introduit de grandes quantites de couverture de sol nu. Les deux methodes de buttage plus recentes n'ont pas entraine ces changements et etaient largement comparables aux proprietes de la tourbe naturelle et aux communautes vegetales. La preservation du profil de la tourbe dans les nouvelles methodes de buttage peut favoriser un retour plus rapide des fonctions de l'ecosysteme. [Traduit par la Redaction] Mots-cles : sol organique, densite apparente, buttage mecanique, rapport C/N, isotopes stables, Introduction An estimated 345 000 km of seismic lines covering 1910 [km.sup.2] have been created in all types of peatlands in the province of Alberta, Canada, for oil and gas [...]