Bacterial community dissimilarity between the surface and subsurface soils equals horizontal differences over several kilometers in the western Tibetan Plateau

Environmental Microbiology, Journal Year: 2016, Volume and Issue: 18(5), P. 1523 - 1533

Published: Feb. 26, 2016

Many studies have investigated patterns in the near-surface soil microbial community over large spatial scales. However, less is known about variation subsurface (15-30 cm of depth) communities. Here we studied depth profiles communities high-elevation soils from Tibet. The relative abundance Acidobacteria, Chloroflexi and Alphaproteobacteria was higher layers, while Actinobacteria, Gemmatimonadetes Betaproteobacteria samples. structure distinct between surface strongly correlating with total carbon (TC) to nitrogen ratio (C/N). differences layers were same as horizontal sites separated by many kilometers. Overall, found that TC C/N best predictors for both distribution. Exploration contribution distance environmental variables composition suggests contemporary environment primary driver distribution this region. Reflecting niche conservatism evolution, each site layer tended be more phylogenetically clustered than expected chance, samples likely

Language: Английский

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Rare taxa maintain the stability of crop mycobiomes and ecosystem functions

Environmental Microbiology, Journal Year: 2020, Volume and Issue: 23(4), P. 1907 - 1924

Published: Sept. 30, 2020

Plants harbour highly diverse mycobiomes which sustain essential functions for host health and productivity. However, ecological processes that govern the plant-mycobiome assembly, interactions their impact on ecosystem remain poorly known. Here we characterized role community assembly of both abundant rare fungal taxa along soil-plant continuums (rhizosphere, phyllosphere endosphere) in maize-wheat/barley rotation system under different fertilization practices at two contrasting sites. Our results indicate mycobiome is shaped predominantly by compartment niche species rather than environmental factors. Moreover, crop-associated communities are dominated few mainly belonging to Sordariomycetes Dothideomycetes, while majority diversity within represented taxa. For plant compartments, sub-community determined stochastic processes. In contrast, more sensitive selection governed deterministic Furthermore, our demonstrate play an important co-occurrence network functioning like crop yield soil enzyme activities. These significantly advance understanding highlight key sustaining stability functions.

Language: Английский

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Two key features influencing community assembly processes at regional scale: Initial state and degree of change in environmental conditions

Molecular Ecology, Journal Year: 2018, Volume and Issue: 27(24), P. 5238 - 5251

Published: Oct. 28, 2018

Abstract Belowground microbial communities strongly influence ecosystem function such that predicting may rely on understanding ecological processes assemble communities. Uncertainty remains, however, in what governs the relative contributions of different processes. To help fill this knowledge gap, we test general hypothesis both initial state and degree change environmental conditions govern assembly do so, leveraged regional‐scale nutrient organic matter addition experiments used soil (SOM) as a proxy integrated conditions. Consistent with our hypothesis, found amount SOM SOM—in response to addition—influenced These influences were most clearly observed at regional scale, suggesting potential scale dependence. More specifically, additions homogenized bacterial community composition due enhanced homogenizing dispersal when content was initially high. In contrast, led divergence variable selection low and/or increased significantly additions. Our findings indicate important connections among conditions, variables conceptual inferences highlight need strengthen between theory biogeochemical modelling.

Language: Английский

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Factors influencing aquatic and terrestrial bacterial community assembly

Environmental Microbiology Reports, Journal Year: 2019, Volume and Issue: 11(3), P. 306 - 315

Published: Jan. 9, 2019

During recent years, many studies have shown that different processes including drift, environmental selection and dispersal can be important for the assembly of bacterial communities in aquatic terrestrial ecosystems. However, we lack a conceptual overview about ecological context factors influence relative importance mechanisms determine their dynamics time space. Focusing on free-living, i.e., nonhost associated, communities, this minireview, therefore, summarizes conceptualizes findings from empirical how (i) factors, such as heterogeneity, disturbances, productivity trophic interactions; (ii) connectivity rates (iii) spatial scale, (iv) community properties traits (v) use taxonomic/phylogenetic or functional metrics processes. We find there is to-date little consistency among suggest future should now address (i)-(v) differ between habitats organisms this, turn, influences temporal spatial-scale dependency microorganisms.

Language: Английский

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Contributions of Quaternary botany to modern ecology and biogeography

Plant Ecology & Diversity, Journal Year: 2019, Volume and Issue: 12(3-4), P. 189 - 385

Published: May 4, 2019

Quaternary (last 2.6 million years) botany involves studying plant megafossils (e.g. tree stumps), macrofossils seeds, leaves), and microfossils pollen, spores) preserved in peat bogs lake sediments. Although have been studied since the late eighteenth century, today is largely dominated by pollen analysis.Quaternary analysis just over 100 years old. It started primarily as a geological tool for correlation, relative dating, climate reconstruction. In 1950 major advance occurred with publication Knut Fægri Johs Iversen of their Text-book Modern Pollen Analysis which provided foundations botanical ecological past dynamics biota biotic systems. The development radiocarbon dating 1950s freed from being dating. As result these developments, became valuable implement long-term ecology biogeography.Selected contributions that has made to biogeography are reviewed. They fall into four general parts: (1) aspects interglacial glacial stages such location nature glacial-stage refugia soil glaciated unglaciated areas; (2) responses environmental change (spreading, extinction, persistence, adaptation); (3) topics potential niches, vegetation, forest dynamics; (4) its application human impact tropical systems, conservation changing world, island palaeoecology, plant–animal interactions, biodiversity patterns time.The future briefly discussed 10 suggestions presented help strengthen it links biogeography. much contribute when used conjunction new approaches ancient-DNA, molecular biomarkers, multi-proxy palaeoecology.

Language: Английский

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