Fungal communities in wet tropical forests: variation in time and space

1995 ◽  
Vol 73 (S1) ◽  
pp. 1391-1398 ◽  
Author(s):  
D. Jean Lodge ◽  
Sharon Cantrell
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Tropical Forest ◽  
Tropical Forests ◽  
Forest Floor ◽  
Forest Litter ◽  
Fungal Communities ◽  
Plant Nutrient ◽  
Fungal Populations ◽  
Fresh Litter

Understanding variation in tropical forest fungal populations and communities is important for assessing fungal biodiversity, as well as for understanding the regulatory roles fungi play in tropical forests. In wet tropical forests, the canopy is typically occupied by certain wood decomposers, endophytes, epiphylls, and pathogens. Aphyllophoraceous canopy fungi are a subset of species found in the understory. Marasmioid agarics in the understory often form extensive networks of rhizomorphs that trap litter; these and other aerial species are rare on the forest floor. Decomposers are stratified within the forest floor, with some species colonizing only fresh litter, others preferring decomposed litter, and others restricted to soil organic matter. Specificity to particular host substrates is frequent among tropical forest litter decomposers and contributes to spatial heterogeneity in fungal communities over the landscape. Litter basidiomycete and microfungal communities in patches of 1 m2 or less do not significantly resemble communities in similar patches located at distances greater than 100 m. Disturbances induce changes in the environment and the abundance of different substrates, resulting in changes in fungal communities through time, and variation over the landscape. Severe disturbances, as well as the slight daily variations in rainfall, profoundly affect populations of fungal decomposers and their influence on plant nutrient availability. Key words: fungi, tropical forests, diversity, stratification, spatial variation, temporal variation.

scholarly journals Dynamics of Forest Floor and Soil Organic Matter Accumulation in Boreal, Temperate, and Tropical Forests

2018 ◽  
pp. 150-151
Author(s):  
Kristiina A. Vogt ◽  
Daniel J. Vogt ◽  
Sandra Brown ◽  
Joel P. Tilley ◽  
Robert L. Edmonds ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Tropical Forests ◽  
Forest Floor ◽  
Organic Matter Accumulation

scholarly journals Altered litter inputs modify carbon and nitrogen storage in soil organic matter in a lowland tropical forest

2020 ◽  
Author(s):  
Emma J. Sayer ◽  
Catherine Baxendale ◽  
Ali J. Birkett ◽  
Laëtitia M. Bréchet ◽  
Biancolini Castro ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Tropical Forest ◽  
Tropical Forests ◽  
C:N Ratio ◽  
N Availability ◽  
Litter Addition ◽  
Lowland Tropical Forest ◽  
Litter Removal ◽  
Som Storage

AbstractSoil organic matter (SOM) in tropical forests is an important store of carbon (C) and nutrients. Although SOM storage could be affected by global changes via altered plant productivity, we know relatively little about SOM stabilisation and turnover in tropical forests compared to temperate systems. Here, we investigated changes in soil C and N within particle size fractions representing particulate organic matter (POM) and mineral-associated organic matter (MAOM) after 13 years of experimental litter removal (L−) and litter addition (L+) treatments in a  lowland tropical forest. We hypothesized that reduced nitrogen (N) availability in L− plots would result in N-mining of MAOM, whereas long-term litter addition would increase POM, without altering the C:N ratio of SOM fractions. Overall, SOM-N declined more than SOM-C with litter removal, providing evidence of N-mining in the L− plots, which increased the soil C:N ratio. However, contrary to expectations, the C:N ratio increased most in the largest POM fraction, whereas the C:N ratio of MAOM remained unchanged. We did not observe the expected increases in POM with litter addition, which we attribute to rapid turnover of unprotected SOM. Measurements of ion exchange rates to assess changes in N availability and soil chemistry revealed that litter removal increased the mobility of ammonium-N and aluminium, whereas litter addition increased the mobility of nitrate-N and iron, which could indicate SOM priming in both treatments. Our study suggests that altered litter inputs affect multiple processes contributing to SOM storage and we propose potential mechanisms to inform future work.

FOREST LITTER CONSTRAINTS ON THE PATHWAYS CONTROLLING SOIL ORGANIC MATTER FORMATION

2021 ◽  
pp. 108447
Author(s):  
Luís F.J. Almeida ◽  
Ivan F. Souza ◽  
Luís C.C. Hurtarte ◽  
Pedro Paulo Teixeira ◽  
Thiago M. Inagaki ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Forest Litter ◽  
Soil Organic Matter Formation

scholarly journals Fungi in Permafrost-Affected Soils of the Canadian Arctic: Horizon- and Site-Specific Keystone Taxa Revealed by Co-Occurrence Network

2021 ◽  
Vol 9 (9) ◽  
pp. 1943
Author(s):  
Milan Varsadiya ◽  
Tim Urich ◽  
Gustaf Hugelius ◽  
Jiří Bárta
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Plant Pathogens ◽  
Close Contact ◽  
Relative Proportion ◽  
Canadian Arctic ◽  
Clustering Coefficient ◽  
Fungal Communities ◽  
Soil Horizon ◽  
Internal Transcribed Spacer Region

Permafrost-affected soil stores a significant amount of organic carbon. Identifying the biological constraints of soil organic matter transformation, e.g., the interaction of major soil microbial soil organic matter decomposers, is crucial for predicting carbon vulnerability in permafrost-affected soil. Fungi are important players in the decomposition of soil organic matter and often interact in various mutualistic relationships during this process. We investigated four different soil horizon types (including specific horizons of cryoturbated soil organic matter (cryoOM)) across different types of permafrost-affected soil in the Western Canadian Arctic, determined the composition of fungal communities by sequencing (Illumina MPS) the fungal internal transcribed spacer region, assigned fungal lifestyles, and by determining the co-occurrence of fungal network properties, identified the topological role of keystone fungal taxa. Compositional analysis revealed a significantly higher relative proportion of the litter saprotroph Lachnum and root-associated saprotroph Phialocephala in the topsoil and the ectomycorrhizal close-contact exploring Russula in cryoOM, whereas Sites 1 and 2 had a significantly higher mean proportion of plant pathogens and lichenized trophic modes. Co-occurrence network analysis revealed the lowest modularity and average path length, and highest clustering coefficient in cryoOM, which suggested a lower network resistance to environmental perturbation. Zi-Pi plot analysis suggested that some keystone taxa changed their role from generalist to specialist, depending on the specific horizon concerned, Cladophialophora in topsoil, saprotrophic Mortierella in cryoOM, and Penicillium in subsoil were classified as generalists for the respective horizons but specialists elsewhere. The litter saprotrophic taxon Cadophora finlandica played a role as a generalist in Site 1 and specialist in the rest of the sites. Overall, these results suggested that fungal communities within cryoOM were more susceptible to environmental change and some taxa may shift their role, which may lead to changes in carbon storage in permafrost-affected soil.

DNA Sequence and Community Structure Diversity of Multi-Year Soil Fungi in Grape of Xinjiang

2021 ◽  
Author(s):  
Tong Liu ◽  
Feng Xue
Keyword(s):  
Organic Matter ◽  
Community Structure ◽  
Soil Organic Matter ◽  
Soil Fungi ◽  
Rhizosphere Soil ◽  
Middle Layer ◽  
Fungal Communities ◽  
Seedless Grape ◽  
Significant Difference ◽  
Vineyard Soil

Abstract This study is designed to understand the community structure and diversity of fungi in the rhizosphere soil of grape. As the sample for this study, the rhizosphere soil of Crimson seedless grape with different planting years was collected from Shihezi in Xinjiang to carry out high-throughput sequencing, by which the complete sequence of soil fungi DNA was identified, and accordingly, the richness and diversity index of fungi were determined. The results showed that the dominant phyla of fungi in the grape rhizosphere soil with different planting years were Ascomycota and Basidiomycota, and the dominant classes of fungi were Sordariomycetes and Dothideomycetes. Soil organic matter, total potassium, total nitrogen and available phosphorus were the main soil fertility factors affecting the abundance and diversity of soil fungal communities, among which soil organic matter had the most significant influence. In addition, the fungal diversity and richness were highest in the middle layer (20-35 cm) of the grape rhizosphere soil with 12 planting years and lowest in the lower layer (35-50 cm) of the grape rhizosphere soil with 5 planting years. Linear discriminant analysis suggested that there were more biomarkers in the vineyard rhizosphere soil with 10 planting years, which meant there were more fungal communities with significant difference in the soil, especially in the middle layer (20-35). The results of this study can provide data reference and theoretical basis for improving vineyard soil quality, evaluating soil microecological effects and improving ecological environment of vineyard soil.

scholarly journals Short-term temperature history affects mineralization of fresh litter and extant soil organic matter, irrespective of agricultural management

2020 ◽  
Vol 150 ◽  
pp. 107985
Author(s):  
Kyle Mason-Jones ◽  
Pim Vrehen ◽  
Kevin Koper ◽  
Jin Wang ◽  
Wim H. van der Putten ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Agricultural Management ◽  
Temperature History ◽  
Short Term ◽  
Fresh Litter

scholarly journals Radiocarbon Dating of Soil Organic Matter Fractions in Andosols in Northern Ecuador

Radiocarbon ◽  
2006 ◽  
Vol 48 (3) ◽  
pp. 337-353 ◽  
Author(s):  
Femke H Tonneijck ◽  
Johannes van der Plicht ◽  
Boris Jansen ◽  
Jacobus M Verstraten ◽  
Henry Hooghiemstra
Keyword(s):  
Organic Matter ◽  
Humic Acid ◽  
Soil Organic Matter ◽  
Forest Floor ◽  
Radiocarbon Dating ◽  
Mineral Soil ◽  
Soil Samples ◽  
Acid Extraction ◽  
Independent Evidence ◽  
Organic Horizons

Volcanic ash soils (Andosols) may offer great opportunities for paleoecological studies, as suggested by their characteristic accumulation of organic matter (OM). However, understanding of the chronostratigraphy of soil organic matter (SOM) is required. Therefore, radiocarbon dating of SOM is necessary, but unfortunately not straightforward. Dating of fractions of SOM obtained by alkali-acid extraction is promising, but which fraction (humic acid or humin) renders the most accurate 14C dates is still subject to debate. To determine which fraction should be used for 14C dating of Andosols and to evaluate if the chronostratigraphy of SOM is suitable for paleoecological research, we measured 14C ages of both fractions and related calibrated ages to soil depth for Andosols in northern Ecuador. We compared the time frames covered by the Andosols with those of peat sequences nearby to provide independent evidence. Humic acid (HA) was significantly older than humin, except for the mineral soil samples just beneath a forest floor (organic horizons), where the opposite was true. In peat sections, 14C ages of HA and humin were equally accurate. In the soils, calibrated ages increased significantly with increasing depth. Age inversions and homogenization were not observed at the applied sampling distances. We conclude that in Andosols lacking a thick organic horizon, dating of HA renders the most accurate results, since humin was contaminated by roots. On the other hand, in mineral soil samples just beneath a forest floor, humin ages were more accurate because HA was then contaminated by younger HA illuviated from the organic horizons. Overall, the chronostratigraphy of SOM in the studied Andosols appears to be suitable for paleoecological research.

Sign in / Sign up

Export Citation Format

Share Document