Metagenomic reconstruction of nitrogen and carbon cycling pathways in forest soil: Influence of different hardwood tree species

AbstractThe soil microbiome plays an essential role in processing and storage of nitrogen (N) and carbon (C), and is influenced by vegetation above-ground through imparted differences in chemistry, structure, mass of plant litter, root physiology, and dominant mycorrhizal associations. We used shotgun metagenomic sequencing and bioinformatic analysis to quantify the abundance and distribution of gene families involved in soil microbial N and C cycling beneath three deciduous hardwood tree species: ectomycorrhizal (ECM)-associated Quercus rubra (red oak), ECM-associated Castanea dentata (American chestnut), and arbuscular mycorrhizal (AM)-associated Prunus serotina (black cherry). Chestnut exhibited the most distinct soil microbiome of the three species, both functionally and taxonomically, with a general suppression of functional genes in the nitrification, denitrification, and nitrate reduction pathways. These changes were related to low inorganic N availability in chestnut stands as soil was modified by poor, low-N litter quality relative to red oak and black cherry soils.IMPORTANCEPrevious studies have used field biogeochemical process rates, isotopic tracing, and targeted gene abundance measurements to study the influence of tree species on ecosystem N and C dynamics. However, these approaches do not enable a comprehensive systems-level understanding of the relationship between microbial diversity and metabolism of N and C below-ground. We analyzed microbial metagenomes from soils beneath red oak, American chestnut, and black cherry stands and showed that tree species can mediate the abundance of key microbial genes involved in N and (to a lesser extent) C metabolism pathways in soil. Our results highlight the genetic framework underlying tree species’ control over soil microbial communities, and below-ground C and N metabolism, and may enable land managers to select tree species to maximize C and N storage in soils.

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TEMPORAL AND SPATIAL PATTERNS OF SPECIFIC LEAF WEIGHT IN SUCCESSIONAL NORTHERN HARDWOOD TREE SPECIES

American Journal of Botany ◽

10.1002/j.1537-2197.1986.tb08555.x ◽

1986 ◽

Vol 73 (8) ◽

pp. 1083-1092 ◽

Cited By ~ 44

Author(s):

Thomas W. Jurik

Keyword(s):

Spatial Patterns ◽

Tree Species ◽

Specific Leaf Weight ◽

Northern Hardwood ◽

Temporal And Spatial Patterns ◽

Leaf Weight ◽

Hardwood Tree ◽

Temporal And Spatial

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Microbial Activity in Forest Soil Under Beech, Spruce, Douglas Fir and Fir

Contemporary Agriculture ◽

10.1515/contagri-2016-0006 ◽

2016 ◽

Vol 65 (1-2) ◽

pp. 33-38

Author(s):

Timea Hajnal-Jafari ◽

Simonida Đurić ◽

Dragana Stamenov ◽

Verica Vasić ◽

Davorka Hackenberger

Keyword(s):

Forest Soil ◽

Microbial Activity ◽

Dehydrogenase Activity ◽

Standard Method ◽

Tree Species ◽

Douglas Fir ◽

Sampling Time ◽

Spectrophotometric Methods ◽

Cellulolytic Microorganisms ◽

Number Of Bacteria

Summary The aim of this research was to investigate the microbial activity in forest soil from different sites under deciduous and coniferous trees in Serbia. One site on Stara planina was under beech trees (Fagus sp.) while another under mixture of spruce (Picea sp.) and Douglas fir (Pseudotsuga sp.). The site on Kopaonik was under mixture of beech (Fagus sp.) and spruce (Picea sp.) trees. The site on Tara was dominantly under fir (Abies sp.), beech (Fagus sp.) and spruce (Picea sp.). The total number of bacteria, the number of actinobacteria, fungi and microorganisms involved in N and C cycles were determined using standard method of agar plates. The activities of dehydrogenase and ß-glucosidase enzymes were measured by spectrophotometric methods. The microbial activity was affected by tree species and sampling time. The highest dehydrogenase activity, total number of bacteria, number of actinobacteria, aminoheterotrophs, amylolytic and cellulolytic microorganisms were determined in soil under beech trees. The highest total number of fungi and number of pectinolytic microorganisms were determined in soil under spruce and Douglas fir trees. The correlation analyses proved the existence of statistically significant interdependency among investigated parameters.

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Canker formation and decay in sugar maple and paper birch infected by Cerrenaunicolor

Canadian Journal of Forest Research ◽

10.1139/x89-031 ◽

1989 ◽

Vol 19 (2) ◽

pp. 225-231 ◽

Cited By ~ 15

Author(s):

Scott A. Enebak ◽

Robert A. Blanchette

Keyword(s):

Cell Wall ◽

Tree Species ◽

Sugar Maple ◽

Callus Formation ◽

White Rot ◽

Northern Hardwood ◽

Paper Birch ◽

Weak Points ◽

Hardwood Tree ◽

Xylem Discoloration

Cerrenaunicolor (Bull.: Fr.) Murr. (= Daedaleaunicolor) (Aphyllophorales, Polyporaceae) was found to cause a canker rot on two northern hardwood tree species, sugar maple (Acersaccharum Marsh.) and paper birch (Betulapapyrifera Marsh.). Pathogenicity of the fungus was determined by inoculation and examination of cankers 6 months, 1.5 years, and 2.5 years later. The two isolates used were found to differ in pathogenicity. Chemical and morphological barriers formed to compartmentalize the fungus. A zone of enhanced cell wall lignification and the formation of suberized impervious cells which composed the necrophylactic periderm in the host were observed. Xylem discoloration, callus formation, and periderm layers were more pronounced in maple than in birch. Cerrenaunicolor moved past host barriers via a mass of hyphae which annually penetrated weak points in the necrophylactic periderm and subsequently killed the adjacent cambium. Once past the necrophylactic periderm and into the xylem, C. unicolor was an aggressive decay organism which caused an extensive white rot. In naturally infected trees, columns of decay were two or three times longer than the cankers. Multiple zones of decayed and discolored wood were present in the xylem as a result of repeated attacks by the fungus.

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