Contrasting ecological processes shape the Eucalyptus phyllosphere bacterial and fungal community assemblies

Soil is the principal habitat and reservoir of fungi that act on ecological processes vital for life on Earth. Understanding soil fungal community structures and the patterns of species distribution is crucial, considering climatic change and the increasing anthropic impacts affecting nature. We evaluated the soil fungal diversity in southeastern Brazil, in a transitional region that harbors patches of distinct biomes and ecoregions. The samples originated from eight habitats, namely: semi-deciduous forest, Brazilian savanna, pasture, coffee and sugarcane plantation, abandoned buildings, owls’ and armadillos’ burrows. Forty-four soil samples collected in two periods were evaluated by metagenomic approaches, focusing on the high-throughput DNA sequencing of the ITS2 rDNA region in the Illumina platform. Normalized difference vegetation index (NDVI) was used for vegetation cover analysis. NDVI values showed a linear relationship with both diversity and richness, reinforcing the importance of a healthy vegetation for the establishment of a diverse and complex fungal community. The owls’ burrows presented a peculiar fungal composition, including high rates of Onygenales, commonly associated with keratinous animal wastes, and Trichosporonales, a group of basidiomycetous yeasts. Levels of organic matter and copper influenced all guild communities analyzed, supporting them as important drivers in shaping the fungal communities’ structures.

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Neutral Processes Drive Seasonal Assembly of the Skin Mycobiome

mSystems ◽

10.1128/msystems.00004-19 ◽

2019 ◽

Vol 4 (2) ◽

Cited By ~ 4

Author(s):

Xinzhao Tong ◽

Marcus H. Y. Leung ◽

David Wilkins ◽

Hedwig H. L. Cheung ◽

Patrick K. H. Lee

Keyword(s):

Human Skin ◽

Fungal Community ◽

Community Dynamics ◽

Seborrheic Dermatitis ◽

Temporal Stability ◽

Skin Microbiome ◽

Skin Microbiota ◽

Ecological Processes ◽

Significant Difference ◽

Healthy Chinese

ABSTRACT The importance of microorganisms to human skin health has led to a growing interest in the temporal stability of skin microbiota. Here we investigated the dynamics and assembly of skin fungal communities (mycobiomes) with amplicon sequencing of samples collected from multiple sites on 24 healthy Chinese individuals across four seasons (in the order of winter, spring, summer, and autumn in a calendar year). We found a significant difference in community compositions between individuals, and intrapersonal community variation increased over time at all body sites. Within each season, the frequency of occurrence of most operational taxonomic units (OTUs) was well fitted by a neutral model, highlighting the importance of stochastic forces such as passive dispersal and ecological drift in skin community assembly. Despite the significant richness contributed by neutrally distributed OTUs, skin coassociation networks were dominated by taxa well-adapted to multiple body sites (forehead, forearm, and palm), although hub species were disproportionately rare. Taken together, these results suggest that while skin mycobiome assembly is a predominantly neutral process, taxa that could be under the influence of selective forces (e.g., host selection) are potentially key to the structure of a community network. IMPORTANCE Fungi are well recognized members of the human skin microbiota and are crucial to cutaneous health. Common cutaneous diseases such as seborrheic dermatitis and dermatophytes are linked to fungal species. Most studies related to skin microbial community dynamics have focused on Western subjects, while non-Western individuals are understudied. In this study, we explore the seasonal changes of the skin mycobiome in a healthy Chinese cohort and identify ecological processes that could possibly give rise to such variations. Our work reveals the dynamic nature of host skin fungal community, highlighting the dominant roles neutral forces play in the seasonal assembly of skin mycobiome. This study provides insight into the microbial ecology of the human skin microbiome and fills a knowledge gap in the literature regarding the dynamics of skin fungal community.

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Stochastic and deterministic drivers of seasonal variation of fungal community in tobacco field soil

PeerJ ◽

10.7717/peerj.6962 ◽

2019 ◽

Vol 7 ◽

pp. e6962

Author(s):

Xing Li ◽

Tianming Li ◽

Delong Meng ◽

Tianbo Liu ◽

Yongjun Liu ◽

...

Keyword(s):

Seasonal Variation ◽

Fungal Community ◽

Community Assembly ◽

High Throughput Sequencing ◽

Null Model ◽

Dispersal Limitation ◽

Community Diversity ◽

Ecological Processes ◽

Soil Fungal Community ◽

Community Variation

Background The soil fungal community plays an important role in global carbon cycling and shows obvious seasonal variations, however, drivers, particularly stochastic drivers, of the seasonal variation in the fungal community have never been addressed in sufficient detail. Methods We investigated the soil fungal community variation between summer growing (SG) and winter fallow (WF) stage, through high throughput sequencing of internal transcribed spacer (ITS) amplicons. Subsequently, we assessed the contribution of different ecological processes to community assembly using null-model-based statistical framework. Results The results showed that the fungal community diversity decreased significantly after tobacco cropping in the SG stage and the composition showed a clear turnover between the WF and SG stages. The variation in community composition was largely attributable to the presence of a small portion of Dothideomycetes in the WF stage that dominated the soil fungal community in the SG stage. The organic matter, temperature, and water content were the main deterministic factors that regulated the fungal community; these factors explained 34.02% of the fungal community variation. Together with the result that the fungal community was mainly assembled by the dispersal process, our results suggested that the stochastic factors played important roles in driving the seasonal variation of fungal community. The dispersal limitation dominated the fungal community assembly during the WF stage when homogenizing dispersal was the main assembly process of the fungal community in the SG stage. Thus, we proposed that the dispersal processes are important drivers for seasonal variation of fungal community in tobacco planted soil.

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Biodiversity of fungal community associated to lichens active against Candida biofilms

Planta Medica ◽

10.1055/s-0036-1596725 ◽

2016 ◽

Vol 81 (S 01) ◽

pp. S1-S381

Author(s):

P Jargeat ◽

M Girardot ◽

C Rouger ◽

W Aucher ◽

M Millot ◽

...

Keyword(s):

Fungal Community

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

10.32942/osf.io/cu4jh ◽

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.

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

10.32942/osf.io/t82ug ◽

2019 ◽

Cited By ~ 1

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.

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Inferring ecological processes underlying the latitudinal diversity gradient in New World swallowtail butterflies (Papilio, Heraclides, andPterourus)

10.1603/ice.2016.109466 ◽

2016 ◽

Author(s):

Hannah L Owens

Keyword(s):

New World ◽

Ecological Processes ◽

Latitudinal Diversity Gradient ◽

Diversity Gradient ◽

Swallowtail Butterflies

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Adoption Decision and Sustainable Utilization of Soil Conservation Technologies: Empirical Evidence from North West Ethiopia

JOURNAL OF ADVANCES IN AGRICULTURE ◽

10.24297/jaa.v10i0.8283 ◽

2019 ◽

Vol 10 ◽

pp. 1853-1863

Author(s):

Kassaye Gurebiyaw Legese ◽

Taye Melese ◽

Tadie Mire ◽

Abebe Birara ◽

Kefale Eniyew

Keyword(s):

Water Conservation ◽

Soil Conservation ◽

Sampling Technique ◽

Household Survey ◽

Ecological Processes ◽

Related Factors ◽

Severe Problem ◽

North West ◽

Household Heads ◽

North Gondar Zone

Soil is a crucial and precious natural resource that govern numerous ecological processes. However, in Ethiopia particularly in north Gondar zone, soil erosion is a severe problem and a major cause of the decline of agricultural productivity. The adoption and diffusion of soil and water conservation practices (SWC), as a way to tackle this challenge, has become an important issue in the development policy agenda in the zone. Therefore, this study was to identify factors affecting Soil conservation investments in the North Gondar zone. Data was collected through interviewed schedule, filed observation and focus group discussion. The multistage sampling technique was employed to select 206 sample households. Both descriptive and econometrics model was used to analyze the collected data. A multivariate profit (MPV) model was used to analyze the effect of demographic, socioeconomic, market, institutional and biophysical related factors on the interdependent investment decisions of SWC practices using household survey. The MPV model analysis indicates that farmers invest a combination of practices at parcel level by considering substitution and complementarity effects of the practices. The results also revealed that age of household heads, literacy status of household heads, off-farm activity, distance of farmlands from homesteads, tropical livestock unit, and access to training were influence farmers’ investments in SWC practices. The overall results indicate that the identified physical, socioeconomic, and institutional factors influence promote or hinder investments in SWC practice so, policymakers should take into consideration these various factors in designing and implementing SWC policies and Programmers.

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