scholarly journals Epiphytic fungal communities vary by substrate type and at sub-meter spatial scales

2020 ◽  
Author(s):  
Kel Cook ◽  
Jyotsna Sharma ◽  
Andrew Taylor ◽  
Ian Herriott ◽  
D Taylor
Keyword(s):  
Spatial Scales ◽  
Fungal Communities ◽  
Substrate Type

scholarly journals Assembly processes lead to divergent soil fungal communities within and among twelve forest ecosystems along a latitudinal gradient

2021 ◽  
Author(s):  
Yong Zheng ◽  
Liang Chen ◽  
Niu-Niu Ji ◽  
Yong-Long Wang ◽  
Cheng Gao ◽  
...  
Keyword(s):  
Ectomycorrhizal Fungi ◽  
Fungal Community ◽  
Community Assembly ◽  
Large Scale ◽  
Spatial Scales ◽  
Geographic Distance ◽  
Latitudinal Gradients ◽  
Fungal Communities ◽  
Environmental Drivers ◽  
Natural Forests

Latitudinal gradients provide opportunities to better understand soil fungal community assembly and its relationship with vegetation, climate, soil and ecosystem function. We quantified the relative importance of stochastic and deterministic processes in structuring soil fungal communities using patterns of community dissimilarity observed within and between twelve natural forests. The results revealed that whole fungal communities and communities of arbuscular and ectomycorrhizal fungi consistently exhibited divergent patterns but with less divergence for ectomycorrhizal fungi at most sites. Within those forests, no clear relationships were observed between the degree of divergence within fungal and plant communities. When comparing communities at larger spatial scales, among the twelve forests, we observed distinct separation in all three fungal groups among tropical, subtropical and temperate biomes. Soil fungal β-diversity patterns between forests were greater when comparing forests exhibiting high habitat turnover, with these patterns being driven to a greater extent in each fungal group by temperature, soil pH, soil carbon and plant community composition than by geographic distance. Taken together, although large-scale community turnover could be attributed to specific environmental drivers, strong divergence during community assembly in forest soils at local scales limits the predictability of fungal community assembly outcomes.

scholarly journals Scale-dependent influences of distance and vegetation on the composition of aboveground and belowground tropical fungal communities

2020 ◽  
Author(s):  
Andre Boraks ◽  
Gregory M. Plunkett ◽  
Thomas Doro ◽  
Frazer Alo ◽  
Chanel Sam ◽  
...  
Keyword(s):  
Fungal Community ◽  
Spatial Scales ◽  
Geographic Distance ◽  
Spatial Dynamics ◽  
Spatial Relationship ◽  
Forest Monitoring ◽  
Fungal Communities ◽  
Symbiotic Relationships ◽  
Tree Community ◽  
Relationship Of

AbstractFungi provide essential ecosystem services and engage in a variety of symbiotic relationships with trees. In this study, we investigate the spatial relationship of trees and fungi at a community level. We characterized the spatial dynamics for above- and belowground fungi using a series of forest monitoring plots, at nested spatial scales, located in the tropical South Pacific. Fungal communities exhibited strong distance decay of similarity across our entire sampling range (3–110,000 m), and also at small spatial scales (< 50 m). Unexpectedly, this pattern was inverted at an intermediate scale (3.7–26 km). At large scales (80–110 km), belowground and aboveground fungal communities responded inversely to increasing geographic distance. Aboveground fungal community turnover (beta diversity) was best explained, at all scales, by geographic distance. In contrast, belowground fungal community turnover was best explained by geographic distance at small scales, and tree community composition at large scales. We demonstrate scale-dependent spatial dynamics of fungal communities, synchronous spatial dynamics for trees and fungi, and the varying influence of habitat versus geographic distance in structuring Soil, Selaginella sp., and Understory fungal communities.

scholarly journals Vegetation and Soil Environment Influence the Spatial Distribution of Root-Associated Fungi in a Mature Beech-Maple Forest

2009 ◽  
Vol 75 (24) ◽  
pp. 7639-7648 ◽  
Author(s):  
David J. Burke ◽  
Juan C. López-Gutiérrez ◽  
Kurt A. Smemo ◽  
Charlotte R. Chan
Keyword(s):  
Community Structure ◽  
Mycorrhizal Fungi ◽  
Spatial Scales ◽  
Plant Distribution ◽  
Fungal Communities ◽  
Herbaceous Plant ◽  
Soil Environment ◽  
Root Tips ◽  
Mature Forest ◽  
Root Fungi

ABSTRACT Although the level of diversity of root-associated fungi can be quite high, the effect of plant distribution and soil environment on root-associated fungal communities at fine spatial scales has received little attention. Here, we examine how soil environment and plant distribution affect the occurrence, diversity, and community structure of root-associated fungi at local patch scales within a mature forest. We used terminal restriction fragment length polymorphism and sequence analysis to detect 63 fungal species representing 28 different genera colonizing tree root tips. At least 32 species matched previously identified mycorrhizal fungi, with the remaining fungi including both saprotrophic and parasitic species. Root fungal communities were significantly different between June and September, suggesting a rapid temporal change in root fungal communities. Plant distribution affected root fungal communities, with some root fungi positively correlated with tree diameter and herbaceous-plant coverage. Some aspects of the soil environment were correlated with root fungal community structure, with the abundance of some root fungi positively correlated with soil pH and moisture content in June and with soil phosphorous (P) in September. Fungal distribution and community structure may be governed by plant-soil interactions at fine spatial scales within a mature forest. Soil P may play a role in structuring root fungal communities at certain times of the year.

scholarly journals Multiscale interactions between plant part and a steep environmental gradient determine plant microbial composition in a tropical watershed

2020 ◽  
Author(s):  
Jared Bernard ◽  
Christopher B. Wall ◽  
Maria S. Costantini ◽  
Randi L. Rollins ◽  
Melissa L. Atkins ◽  
...  
Keyword(s):  
Environmental Gradient ◽  
Spatial Scales ◽  
Spatial Dynamics ◽  
Distribution Patterns ◽  
Plant Part ◽  
Fungal Communities ◽  
Plant Tissues ◽  
Microbial Composition ◽  
Plant Parts ◽  
Tropical Watershed

AbstractPlant microbiomes are shaped by forces working at different spatial scales. Environmental factors determine a pool of potential symbionts while host physiochemical factors influence how those microbes associate with distinct plant tissues. Interactions between these scales, however, are seldom considered. Here we analyze epiphytic microbes from nine Hibiscus tiliaceus trees across a steep environmental gradient within a single Hawaiian watershed. At each location we sampled eight microhabitats: leaves, petioles, axils, stems, roots, and litter from the plant, as well as surrounding air and soil. While the composition of microbial communities is driven primarily by microhabitat, this variable predicted more than twice the compositional variance for bacteria compared to fungi. Fungal community compositional dissimilarity increased more rapidly along the gradient than did bacteria. Additionally, the spatial dynamics of fungal communities differed among plant parts, and these differences influenced the distribution patterns and range size of individual taxa. Within plants, microbes were compositionally nested such that aboveground communities contained a subset of the diversity found belowground. Our findings identify potential differences underlying the mechanisms shaping communities of fungi and bacteria associated with plants, and indicate an interaction between assembly mechanisms working simultaneously on different spatial scales.

High spatial resolution x-ray microanalysis of interfaces

1995 ◽  
Vol 53 ◽  
pp. 284-285
Author(s):  
J. R. Michael
Keyword(s):  
Spatial Resolution ◽  
Electron Probe ◽  
Solid Angle ◽  
Collection Efficiency ◽  
Spatial Scales ◽  
Energy Dispersive Spectrometer ◽  
X Rays ◽  
X Ray ◽  
Probe Size ◽  
Brightness Field

X-ray microanalysis in the analytical electron microscope (AEM) refers to a technique by which chemical composition can be determined on spatial scales of less than 10 nm. There are many factors that influence the quality of x-ray microanalysis. The minimum probe size with sufficient current for microanalysis that can be generated determines the ultimate spatial resolution of each individual microanalysis. However, it is also necessary to collect efficiently the x-rays generated. Modern high brightness field emission gun equipped AEMs can now generate probes that are less than 1 nm in diameter with high probe currents. Improving the x-ray collection solid angle of the solid state energy dispersive spectrometer (EDS) results in more efficient collection of x-ray generated by the interaction of the electron probe with the specimen, thus reducing the minimum detectability limit. The combination of decreased interaction volume due to smaller electron probe size and the increased collection efficiency due to larger solid angle of x-ray collection should enhance our ability to study interfacial segregation.

Experimentally altered rainfall regimes and host root traits affect grassland arbuscular mycorrhizal fungal communities

2019 ◽  
Author(s):  
Coline Deveautour ◽  
Suzanne Donn ◽  
Sally Power ◽  
Kirk Barnett ◽  
Jeff Powell
Keyword(s):  
Fungal Community ◽  
Community Assembly ◽  
Root Length ◽  
Specific Root Length ◽  
Root Traits ◽  
Arbuscular Mycorrhizal ◽  
Fungal Communities ◽  
Rainfall Regime ◽  
Precipitation Regimes ◽  
Rainfall Regimes

Future climate scenarios predict changes in rainfall regimes. These changes are expected to affect plants via effects on the expression of root traits associated with water and nutrient uptake. Associated microorganisms may also respond to these new precipitation regimes, either directly in response to changes in the soil environment or indirectly in response to altered root trait expression. We characterised arbuscular mycorrhizal (AM) fungal communities in an Australian grassland exposed to experimentally altered rainfall regimes. We used Illumina sequencing to assess the responses of AM fungal communities associated with four plant species sampled in different watering treatments and evaluated the extent to which shifts were associated with changes in root traits. We observed that altered rainfall regimes affected the composition but not the richness of the AM fungal communities, and we found distinctive communities in the increased rainfall treatment. We found no evidence of altered rainfall regime effects via changes in host physiology because none of the studied traits were affected by changes in rainfall. However, specific root length was observed to correlate with AM fungal richness, while concentrations of phosphorus and calcium in root tissue and the proportion of root length allocated to fine roots were correlated to community composition. Our study provides evidence that climate change and its effects on rainfall may influence AM fungal community assembly, as do plant traits related to plant nutrition and water uptake. We did not find evidence that host responses to altered rainfall drive AM fungal community assembly in this grassland ecosystem.

Temporal dynamics of mycorrhizal fungal communities and co-associations with grassland plant communities following experimental manipulation of rainfall

2019 ◽  
Author(s):  
Coline Deveautour ◽  
Sally Power ◽  
Kirk Barnett ◽  
Raul Ochoa-Hueso ◽  
Suzanne Donn ◽  
...  
Keyword(s):  
Community Composition ◽  
Plant Community ◽  
Plant Communities ◽  
Fungal Community ◽  
Mycorrhizal Fungi ◽  
Temporal Dynamics ◽  
Arbuscular Mycorrhizal ◽  
Fungal Communities ◽  
Plant Responses ◽  
Rainfall Regimes

Climate models project overall a reduction in rainfall amounts and shifts in the timing of rainfall events in mid-latitudes and sub-tropical dry regions, which threatens the productivity and diversity of grasslands. Arbuscular mycorrhizal fungi may help plants to cope with expected changes but may also be impacted by changing rainfall, either via the direct effects of low soil moisture on survival and function or indirectly via changes in the plant community. In an Australian mesic grassland (former pasture) system, we characterised plant and arbuscular mycorrhizal (AM) fungal communities every six months for nearly four years to two altered rainfall regimes: i) ambient, ii) rainfall reduced by 50% relative to ambient over the entire year and iii) total summer rainfall exclusion. Using Illumina sequencing, we assessed the response of AM fungal communities sampled from contrasting rainfall treatments and evaluated whether variation in AM fungal communities was associated with variation in plant community richness and composition. We found that rainfall reduction influenced the fungal communities, with the nature of the response depending on the type of manipulation, but that consistent results were only observed after more than two years of rainfall manipulation. We observed significant co-associations between plant and AM fungal communities on multiple dates. Predictive co-correspondence analyses indicated more support for the hypothesis that fungal community composition influenced plant community composition than vice versa. However, we found no evidence that altered rainfall regimes were leading to distinct co-associations between plants and AM fungi. Overall, our results provide evidence that grassland plant communities are intricately tied to variation in AM fungal communities. However, in this system, plant responses to climate change may not be directly related to impacts of altered rainfall regimes on AM fungal communities. Our study shows that AM fungal communities respond to changes in rainfall but that this effect was not immediate. The AM fungal community may influence the composition of the plant community. However, our results suggest that plant responses to altered rainfall regimes at our site may not be resulting via changes in the AM fungal communities.

Spatial regularities between non-immigrant and immigrant numbers in Canada

2014 ◽  
Vol 11 (1) ◽  
pp. 90-100
Author(s):  
Yigit Aydede
Keyword(s):  
Fixed Effects ◽  
Spatial Scales ◽  
National Scale ◽  
Pooled Data

The present study intends to reveal spatial regularities between non-immigrant and immigrant numbers in two different ways. First, it questions the existence of those regularities when spatial scales get finer. Second, it uses pooled data over four population censuses covering the period from 1991 to 2006, which enabled us to apply appropriate techniques to remove those unobserved fixed effects so that the estimations would accurately identify the linkage between local immigrant and non-immigrant numbers. The results provide evidence about the existence of negative spatial regularities between non-immigrant and immigrant numbers in Canada at national scale.

Sign in / Sign up

Export Citation Format

Share Document