Evidence of Microbial Regulation of Biogeochemical Cycles from a Study on Methane Flux and Land Use Change

ABSTRACTMicrobes play an essential role in ecosystem functions, including carrying out biogeochemical cycles, but are currently considered a black box in predictive models and all global biodiversity debates. This is due to (i) perceived temporal and spatial variations in microbial communities and (ii) lack of ecological theory explaining how microbes regulate ecosystem functions. Providing evidence of the microbial regulation of biogeochemical cycles is key for predicting ecosystem functions, including greenhouse gas fluxes, under current and future climate scenarios. Using functional measures, stable-isotope probing, and molecular methods, we show that microbial (community diversity and function) response to land use change is stable over time. We investigated the change in net methane flux and associated microbial communities due to afforestation of bog, grassland, and moorland. Afforestation resulted in the stable and consistent enhancement in sink of atmospheric methane at all sites. This change in function was linked to a niche-specific separation of microbial communities (methanotrophs). The results suggest that ecological theories developed for macroecology may explain the microbial regulation of the methane cycle. Our findings provide support for the explicit consideration of microbial data in ecosystem/climate models to improve predictions of biogeochemical cycles.

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Future effects of climate and land-use change on terrestrial vertebrate community diversity under different scenarios

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2018.0792 ◽

2018 ◽

Vol 285 (1881) ◽

pp. 20180792 ◽

Cited By ~ 64

Author(s):

Tim Newbold

Keyword(s):

Climate Change ◽

Land Use ◽

Land Use Change ◽

Community Diversity ◽

Ecosystem Functions ◽

Combined Effects ◽

Climate Change Effects ◽

Terrestrial Vertebrate ◽

Data Limitations ◽

Business As Usual

Land-use and climate change are among the greatest threats facing biodiversity, but understanding their combined effects has been hampered by modelling and data limitations, resulting in part from the very different scales at which land-use and climate processes operate. I combine two different modelling paradigms to predict the separate and combined (additive) effects of climate and land-use change on terrestrial vertebrate communities under four different scenarios. I predict that climate-change effects are likely to become a major pressure on biodiversity in the coming decades, probably matching or exceeding the effects of land-use change by 2070. The combined effects of both pressures are predicted to lead to an average cumulative loss of 37.9% of species from vertebrate communities under ‘business as usual’ (uncertainty ranging from 15.7% to 54.2%). Areas that are predicted to experience the effects of both pressures are concentrated in tropical grasslands and savannahs. The results have important implications for the conservation of biodiversity in future, and for the ability of biodiversity to support important ecosystem functions, upon which humans rely.

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Deintensification of land use leads to recovery of soil microbial community composition and function after land use change in Ethiopia

10.22541/au.161770662.29935833/v1 ◽

2021 ◽

Author(s):

Yoseph Delelegn ◽

Witoon Purahong ◽

Ali Nawaz ◽

Hans Sandén ◽

Douglas Godbold ◽

...

Keyword(s):

Land Use ◽

Microbial Community ◽

Land Use Change ◽

Microbial Communities ◽

Soil Microbial Community ◽

Microbial Community Composition ◽

Soil Microbial Communities ◽

Natural Forest ◽

Ecosystem Functions ◽

Soil Microbial

Ethiopia has undergone significant land use change during the past centuries, particularly deforestation. These changes have resulted in the loss of topsoil as well as the associated soil ecosystem functions. Grazing exclusion and planting of eucalyptus are measures used to recover degraded lands and reduce deforestation, respectively. Using a gradient of the intensity of land use from natural forest to croplands, we investigated whether these measures also result in restoration of the soil microbial community. We identified the soil bacterial and fungal communities using paired-end amplicon sequencing. A total of 12,765 fungal and 12,325 bacterial OTUs were detected in the five land use types, and only ca. 2% and 17% were shared among the land uses, respectively. Total fungal and bacterial OTU richness was not significantly affected by land use change, but the conversion of forest to cropland resulted in the loss of approximately 40% and 11% of the total native fungal and bacterial OTUs, respectively. Soil pH, C, N, and aggregate stability were key factors corresponding to the overall bacterial and fungal community compositions. We also showed relationships between the microbial functional group and enzyme activities. The exclusion of grazing led to an enrichment of soil microbial communities that overlapped with the communities of the natural forest. Our results suggest that remnant native forests act as refugia for microbial communities and that restoration of microbial communities and concomitant recovery of ecosystem function via deintensification of land use is possible. Keywords: ectomycorrhiza, ericoid mycorrhiza, exclosure, microbial diversity, soil enzymes

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Effects of Urban Land-Use Change on Biogeochemical Cycles

Terrestrial Ecosystems in a Changing World - Global Change — The IGBP Series ◽

10.1007/978-3-540-32730-1_5 ◽

2007 ◽

pp. 45-58 ◽

Cited By ~ 41

Author(s):

Richard V. Pouyat ◽

Diane E. Pataki ◽

Kenneth T. Belt ◽

Peter M. Groffman ◽

John Hom ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Biogeochemical Cycles ◽

Urban Land ◽

Urban Land Use ◽

Urban Land Use Change

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Captured metagenomics reveals high spatial variability in functional potential in CH4 producing and consuming microorganisms in a temperate Swedish peatland.

10.5194/egusphere-egu21-10861 ◽

2021 ◽

Author(s):

Joel White ◽

Lena Ström ◽

Dag Ahrén ◽

Janne Rinne ◽

Veiko Lehsten

Keyword(s):

Microbial Communities ◽

Root Zone ◽

Water Concentration ◽

Methane Flux ◽

Functional Genes ◽

Molecular Technique ◽

Atmospheric Methane ◽

Functional Potential ◽

Methane Budget ◽

Methane Metabolism

Microbial communities of methane producing methanogens and consuming methanotrophs play an important role for the earths atmospheric methane budget. Despite their global significance, the functional potential of these communities is poorly understood. To investigate this, we applied the molecular technique, captured metagenomics, to identify the variability in functional diversity of microorganisms involved in the metabolism of methanein an environmentally controlled laboratory study. Nine plant-peat mesocosms dominated by the sedge Eriophorum vaginatum, with varying coverage, were collected from a temperate natural wetland is Sweden and subjected to a simulated growing season. Samples for analysis of captured metagenomes were taken from the top, bottom and root adjacent zone at the end of the experiment. In addition, over the simulated season, measured gas fluxes of carbon dioxide (CO2) and CH4, &#948;13C of emitted CH4 and the pore water concentration of dissolved methane and low molecular weight organic acids were recorded. The functional genes resulting from the captured metagenomes had a higher Shannon &#945;-diversity in the root zone when compared to the bottom and top. Sequences coding for methane metabolism were significantly more diverse in the root and bottom zones when compared to the top. However, the frequency of Acetyl-CoA decarbonylase and methane monooxygenase subunit A were significantly higher in the high emitting methane flux category when compared to the medium and low emitting mesocosms. We conclude that captured metagenomic analyses of functional genes provides a good measure of the functional potential methanogenic and methanotrophic microbial communities. This technique can be used to investigate how methanogens and methanotrophs function in peatlands and thus, contribute to the concentration of atmospheric methane.

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Land use change from upland to paddy field in Mollisols drives soil aggregation and associated microbial communities

Applied Soil Ecology ◽

10.1016/j.apsoil.2019.09.001 ◽

2020 ◽

Vol 146 ◽

pp. 103351 ◽

Cited By ~ 8

Author(s):

Xin Li ◽

Huihui Zhang ◽

Minglong Sun ◽

Nan Xu ◽

Guangyu Sun ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Microbial Communities ◽

Paddy Field ◽

Soil Aggregation

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Land‐use change affects size spectra, energy flux and ecosystem functions in litter and soil invertebrates

Journal of Animal Ecology ◽

10.1111/1365-2656.13144 ◽

2019 ◽

Vol 88 (12) ◽

pp. 1828-1831

Author(s):

Roswitha B. Ehnes

Keyword(s):

Land Use ◽

Land Use Change ◽

Energy Flux ◽

Soil Invertebrates ◽

Ecosystem Functions ◽

Size Spectra

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Effects of land‐use change on community diversity and composition are highly variable among functional groups

Ecological Applications ◽

10.1002/eap.1973 ◽

2019 ◽

Vol 29 (7) ◽

Cited By ~ 4

Author(s):

Stuart I. Graham ◽

Margaret F. Kinnaird ◽

Timothy G. O'Brien ◽

Tor‐G Vågen ◽

Leigh A. Winowiecki ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Functional Groups ◽

Community Diversity ◽

Effects Of Land Use

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Microbial Communities and Processes under Climate and Land-use Change in the Tropics

Climate Change and Microbial Ecology: Current Research and Future Trends (Second Edition) ◽

10.21775/9781913652579.15 ◽

2020 ◽

Author(s):

Stephen A. Wood ◽

Krista McGuire ◽

Jonathan E. Hickman

Keyword(s):

Land Use ◽

Land Use Change ◽

Microbial Communities ◽

The Tropics

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Comprehensive Assessment of the Effect of Urban Built-Up Land Expansion and Climate Change on Net Primary Productivity

Complexity ◽

10.1155/2020/8489025 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Pengyan Zhang ◽

Yanyan Li ◽

Wenlong Jing ◽

Dan Yang ◽

Yu Zhang ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

Land Use Change ◽

Primary Productivity ◽

Net Primary Productivity ◽

Urban Expansion ◽

Ecosystem Functions ◽

Rapid Urbanization ◽

Important Indicator ◽

The Impact

Urbanization is causing profound changes in ecosystem functions at local and regional scales. The net primary productivity (NPP) is an important indicator of global change, rapid urbanization and climate change will have a significant impact on NPP, and urban expansion and climate change in different regions have different impacts on NPP, especially in densely populated areas. However, to date, efforts to quantify urban expansion and climate change have been limited, and the impact of long-term continuous changes in NPP has not been well understood. Based on land use data, night light data, NPP data, climate data, and a series of social and economic data, we performed a comprehensive analysis of land use change in terms of type and intensity and explored the pattern of urban expansion and its relationship with NPP and climate change for the period of 2000–2015, taking Zhengzhou, China, as an example. The results show that the major form of land use change was cropland to built-up land during the 2000–2015 period, with a total area of 367.51 km2 converted. The NPP exhibited a generally increasing trend in the study area except for built-up land and water area. The average correlation coefficients between temperature and NPP and precipitation and NPP were 0.267 and 0.020, respectively, indicating that an increase in temperature and precipitation can promote NPP despite significant spatial differences. During the examined period, most expansion areas exhibited an increasing NPP trend, indicating that the influence of urban expansion on NPP is mainly characterized by an evident influence of the expansion area. The study can provide a reference for Zhengzhou and even the world's practical research to improve land use efficiency, increase agricultural productivity and natural carbon sinks, and maintain low-carbon development.

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