Ectomycorrhizal fungi contribute to soil organic matter cycling in sub-boreal forests

Phillips, Lori A.; Ward, Valerie; Jones, Melanie D.

doi:10.1038/ismej.2013.195

Cited by 152 publications

(85 citation statements)

References 104 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Genera and species from different functional groups dominated at these stages of postfire forest development ( Fig. 4; see also Mycorrhizal fungi are crucial in SOM transformations (58)(59)(60). The ECM fungus Paxillus involutus can convert SOM using a mechanism similar to that employed by brown-rot fungi using Fenton chemistry (61).…”

Section: Discussionmentioning

confidence: 99%

Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence

Sun

Santalahti

Pumpanen

et al. 2015

Appl Environ Microbiol

126

View full text Add to dashboard Cite

Forest fires are a common natural disturbance in forested ecosystems and have a large impact on the microbial communities in forest soils. The response of soil fungal communities to forest fire is poorly documented. Here, we investigated fungal community structure and function across a 152-year boreal forest fire chronosequence using high-throughput sequencing of the internal transcribed spacer 2 (ITS2) region and a functional gene array (GeoChip). Our results demonstrate that the boreal forest soil fungal community was most diverse soon after a fire disturbance and declined over time. The differences in the fungal communities were explained by changes in the abundance of basidiomycetes and ascomycetes. Ectomycorrhizal (ECM) fungi contributed to the increase in basidiomycete abundance over time, with the operational taxonomic units (OTUs) representing the genera Cortinarius and Piloderma dominating in abundance. Hierarchical cluster analysis by using gene signal intensity revealed that the sites with different fire histories formed separate clusters, suggesting differences in the potential to maintain essential biogeochemical soil processes. The site with the greatest biological diversity had also the most diverse genes. The genes involved in organic matter degradation in the mature forest, in which ECM fungi were the most abundant, were as common in the youngest site, in which saprotrophic fungi had a relatively higher abundance. This study provides insight into the impact of fire disturbance on soil fungal community dynamics. Boreal forest soils play an important role in the global carbon cycle (1) and are a net sink for atmospheric CO 2 (2, 3). Approximately 16% of the terrestrial carbon (C) stock is estimated to be stored in the boreal forest ecosystem (1). Fire is a natural disturbance in most forest ecosystems (4), and about 1% of the boreal forest burns annually (5). The frequency of forest fires in the northern boreal zone is expected to increase because of rising temperatures and more frequent dry periods resulting from ongoing climate change (6).Soil microbes perform essential ecological functions in forested ecosystems via nutrient cycling and decomposition of organic matter. Microbial activities control the turnover of organic C in soil and thus contribute to global C cycling (7). Fungi are the predominant decomposers in boreal soils and play a central role in the turnover of carbon and nitrogen (8). Ectomycorrhizal fungi form symbioses with both trees and ground vegetation in boreal forests. Many species of ground vegetation can additionally form symbioses with ericoid mycorrhizal fungi. Boreal forest ecosystem productivity is linked to plant nutrient acquisition from the microbial community via soil organic matter (SOM) decomposition. Forest fires result in the loss of mycorrhizal host plants and may modify the SOM chemistry, leading to dramatic changes in soil microbial activity (9, 10). Fire disturbance often increases soil pH and causes changes in soil temperature due to loss of canopy cover, bo...

show abstract

Section: Discussionmentioning

confidence: 99%

Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence

Sun

Santalahti

Pumpanen

et al. 2015

Appl Environ Microbiol

126

View full text Add to dashboard Cite

show abstract

“…It is likely that keeping the material confined in the mesh bags has prevented the displacement of the compost-borne community. Other researchers have used gammaradiation to sterilize the OM added to the mesh bags and and mineral horizons (on the right side) of control and fertilized plots at the Norway spruce forest (n = 3) obtained community composition with ECM and saprotrophic fungal abundances of 70% and less than 9% relative to the total fungal abundance, respectively (Phillips et al 2014). Nevertheless, it is important to bear in mind that the compost-borne fungi, which were present in mesh bags at both horizons and treatments, may or may not be adapted to the new conditions imposed in the environment.…”

Section: Discussionmentioning

confidence: 99%

“…In addition to saprotrophic fungi, ectomycorrhizal (ECM) fungi constitute another major microbial group in boreal and northern temperate forests and may play an important role in OM decomposition. Unlike saprotrophs, ECM fungi forage the SOM to obtain nutrients such as N and P for the host plant and receive in return plant photosynthate C. Nevertheless, the ability of ECM fungi to produce oxidative enzymes suggests a potential role for these microbes in the decomposition of soil OM (Bödeker et al 2014;Phillips et al 2014). Furthermore, recent studies have shown that ECM fungi have retained similar oxidative capacity as saprotrophic fungi (Shah et al 2016).…”

mentioning

confidence: 99%

Chemical changes in organic matter after fungal colonization in a nitrogen fertilized and unfertilized Norway spruce forest

et al. 2017

View full text Add to dashboard Cite

Background and aims Decomposition and transformation of organic matter (OM) in forest soils are conducted by the concomitant action of saprotrophic and mycorrhizal fungi. Here, we examine chemical changes in OM after fungal colonization in nitrogen fertilized and unfertilized soils from a Norway spruce forest. Methods Sand-filled bags amended with composted maize leaves were placed in the forest soil and harvested after 17 months. Infrared and near edge X-ray absorption fine structure spectroscopies were used to study the chemical changes in the OM. Fungal community composition of the bags was also evaluated. Results The proportion of ectomycorrhizal fungi declined in the fertilized plots, but the overall fungal community composition was similar between N treatments. Decomposition of the OM was, independently of the N level or soil horizon, accompanied by an increase of C/N ratio of the mesh-bag content. Moreover, the proportions of carboxylic compounds in the incubated OM increased in the mineral horizon, while heterocyclic-N compounds decreased, especially in unfertilized plots with higher N demand from the trees. Conclusions Our results indicate that more oxidized organic C and less heterocyclic-N proportions in the OM remain after fungal colonization in the mineral layers, and suggest that ectomycorrhizal fungi transfer less heterocyclic-N from the mesh bags to the host trees under high N levels.

show abstract

“…Although pine naturally exist in a relationship with ectomycorrhizal and saprotrophic fungi which significantly contribute to C cycling by SOM decomposition [56,57], here we focused only on bacteria from the perspective of microbial ecology, to obtain information on the structure and function of the microbial community members that were able to sustain in these humics-free basic conditions.…”

Section: Rhizospheric Microbiomementioning

confidence: 99%

Molecular and Microscopic Insights into the Formation of Soil Organic Matter in a Red Pine Rhizosphere

Dohnálková

Tfaily

Smith

et al. 2017

Soils

View full text Add to dashboard Cite

Microbially-derived carbon inputs to soils play an important role in forming soil organic matter (SOM), but detailed knowledge of basic mechanisms of carbon (C) cycling, such as stabilization of organic C compounds originating from rhizodeposition, is scarce. This study aimed to investigate the stability of rhizosphere-produced carbon components in a model laboratory mesocosm of Pinus resinosa grown in a designed mineral soil mix with limited nutrients. We utilized a suite of advanced imaging and molecular techniques to obtain a molecular-level identification of newly-formed SOM compounds, and considered implications regarding their degree of long-term persistence. The microbes in this controlled, nutrient-limited system, without pre-existing organic matter, produced extracellular polymeric substances that formed associations with nutrient-bearing minerals and contributed to the microbial mineral weathering process. Electron microscopy revealed unique ultrastructural residual signatures of biogenic C compounds, and the increased presence of an amorphous organic phase associated with the mineral phase was evidenced by X-ray diffraction. These findings provide insight into the formation of SOM products in ecosystems, and show that the plant-and microbially-derived material associated with mineral matrices may be important components in current soil carbon models.

show abstract

Ectomycorrhizal fungi contribute to soil organic matter cycling in sub-boreal forests

Cited by 152 publications

References 104 publications

Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence

Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence

Chemical changes in organic matter after fungal colonization in a nitrogen fertilized and unfertilized Norway spruce forest

Molecular and Microscopic Insights into the Formation of Soil Organic Matter in a Red Pine Rhizosphere

Contact Info

Product

Resources

About