Structure and resilience of fungal communities in Alaskan boreal forest soilsThis article is one of a selection of papers from The Dynamics of Change in Alaska’s Boreal Forests: Resilience and Vulnerability in Response to Climate Warming

Autor: D. Lee Taylor, Kelsie E. StoneK.E. Stone, Ian C. Herriott, Jack W. McFarland, Michael G. Booth, Mary Beth Leigh
Rok vydání: 2010
Předmět:
Zdroj: Canadian Journal of Forest Research. 40:1288-1301
ISSN: 1208-6037
0045-5067
DOI: 10.1139/x10-081
Popis: This paper outlines molecular analyses of soil fungi within the Bonanza Creek Long Term Ecological Research program. We examined community structure in three studies in mixed upland, black spruce (Picea mariana (Mill.) BSP), and white spruce (Picea glauca (Moench) Voss) forests and examined taxa involved in cellulose degradation at one upland site. We found that soil horizon was the factor by which fungal communities were most strongly structured and that pre- dictable turnover in upland fungal species occurred through succession. Communities from consecutive summers were not significantly different, indicating that interannual variation was small in relation to differences between forest types and soil horizons, yet the community at a seasonal study site underwent significant changes within a year. In each study, my- corrhizal fungi dominated the community. Fungi rather than bacteria appeared to dominate ( 13 C)cellulose degradation, with strongest growth in taxa that were not dominant members of the untreated community, including members of the ge- nus Sebacina. Overall, our results point to considerable interannual resilience juxtaposed with narrow niche partitioning and the capacity of individual taxa in these hyperdiverse communities to respond strongly to resource inputs and changes in other abiotic environmental parameters such as temperature. Our data double the cumulative total of fungal sequences in GenBank and together achieve a better picture of fungal communities here than for any other ecosystem on earth at this time. Resume´ : Cet article decrit les analyses moleculaires effectuees sur les champignons du sol dans le cadre du programme de recherche a long terme en ecologie de Bonanza Creek. Nous avons etudiela structure des communautes par le biais de trois etudes portant sur des forets mixtes en milieu sec, d'epinette noire (Picea mariana (Mill.) BSP) et d'epinette blanche (Picea glauca (Moench) Voss) et nous avons etudieles taxons impliques dans la degradation de la cellulose dans une sta- tion seche. Nous avons trouveque l'horizon du sol etait le facteur preponderant dans la structuration des communautes fongiques et que le renouvellement previsible des especes fongiques en milieu sec se produisait par l'entremise de la suc- cession. Les communautes presentes d'un eteal'autre n'etaient pas significativement differentes indiquant que la variation interannuelle etait faible comparativement aux differences entre les types de foret et les horizons du sol. Par contre, la communautepresente sur le site d'une etude saisonniere a subi des changements significatifs a l'interieur d'une annee. Dans chaque etude, les champignons mycorhiziens dominaient la communaute ´. Les champignons plutot que les bacteries semblaient dominer la degradation de la ( 13 C)cellulose; la plus forte croissance a eteobservee parmi les taxons qui n'etaient pas des membres dominants de la communautenon traitee, incluant des membres du genre Sebacina. Globale- ment, nos resultats font ressortir la grande resilience interannuelle juxtaposeead'etroites niches ecologiques ainsi que la capacitede taxons particuliers dans ces communautes hyper diversifiees de reagir fortement aux apports de ressources et a la variation d'autres parametres environnementaux. Nos donnees viennent doubler le total cumulatif de sequences fongi- ques dans GenBank et ensemble donnent ace jour une meilleure image des communautes fongiques ici que dans n'im- porte quel autre ecosysteme ailleurs dans le monde. (Traduit par la Redaction)
Databáze: OpenAIRE