scholarly journals Long-Term Warming Alters Carbohydrate Degradation Potential in Temperate Forest Soils

2016 ◽  
Vol 82 (22) ◽  
pp. 6518-6530 ◽  
Author(s):  
Grace Pold ◽  
Andrew F. Billings ◽  
Jeff L. Blanchard ◽  
Daniel B. Burkhardt ◽  
Serita D. Frey ◽  
...  
Keyword(s):  
Climate Change ◽  
Microbial Communities ◽  
Soil Carbon ◽  
Carbon Cycling ◽  
Temperate Forest ◽  
Mineral Soil ◽  
Soil Microbial Communities ◽  
Organic Horizon ◽  
Soil Microbial ◽  
Carbohydrate Degradation

ABSTRACTAs Earth's climate warms, soil carbon pools and the microbial communities that process them may change, altering the way in which carbon is recycled in soil. In this study, we used a combination of metagenomics and bacterial cultivation to evaluate the hypothesis that experimentally raising soil temperatures by 5°C for 5, 8, or 20 years increased the potential for temperate forest soil microbial communities to degrade carbohydrates. Warming decreased the proportion of carbohydrate-degrading genes in the organic horizon derived from eukaryotes and increased the fraction of genes in the mineral soil associated withActinobacteriain all studies. Genes associated with carbohydrate degradation increased in the organic horizon after 5 years of warming but had decreased in the organic horizon after warming the soil continuously for 20 years. However, a greater proportion of the 295 bacteria from 6 phyla (10 classes, 14 orders, and 34 families) isolated from heated plots in the 20-year experiment were able to depolymerize cellulose and xylan than bacterial isolates from control soils. Together, these findings indicate that the enrichment of bacteria capable of degrading carbohydrates could be important for accelerated carbon cycling in a warmer world.IMPORTANCEThe massive carbon stocks currently held in soils have been built up over millennia, and while numerous lines of evidence indicate that climate change will accelerate the processing of this carbon, it is unclear whether the genetic repertoire of the microbes responsible for this elevated activity will also change. In this study, we showed that bacteria isolated from plots subject to 20 years of 5°C of warming were more likely to depolymerize the plant polymers xylan and cellulose, but that carbohydrate degradation capacity is not uniformly enriched by warming treatment in the metagenomes of soil microbial communities. This study illustrates the utility of combining culture-dependent and culture-independent surveys of microbial communities to improve our understanding of the role changing microbial communities may play in soil carbon cycling under climate change.

scholarly journals Soil Microbial Community Responses to a Decade of Warming as Revealed by Comparative Metagenomics

2013 ◽  
Vol 80 (5) ◽  
pp. 1777-1786 ◽  
Author(s):  
Chengwei Luo ◽  
Luis M. Rodriguez-R ◽  
Eric R. Johnston ◽  
Liyou Wu ◽  
Lei Cheng ◽  
...  
Keyword(s):  
Climate Change ◽  
Microbial Communities ◽  
Molecular Mechanisms ◽  
Cellulose Degradation ◽  
Global Climate ◽  
Soil Microbial Communities ◽  
Predictive Ability ◽  
Metagenomic Data ◽  
Data Sets ◽  
Soil Microbial

ABSTRACTSoil microbial communities are extremely complex, being composed of thousands of low-abundance species (<0.1% of total). How such complex communities respond to natural or human-induced fluctuations, including major perturbations such as global climate change, remains poorly understood, severely limiting our predictive ability for soil ecosystem functioning and resilience. In this study, we compared 12 whole-community shotgun metagenomic data sets from a grassland soil in the Midwestern United States, half representing soil that had undergone infrared warming by 2°C for 10 years, which simulated the effects of climate change, and the other half representing the adjacent soil that received no warming and thus, served as controls. Our analyses revealed that the heated communities showed significant shifts in composition and predicted metabolism, and these shifts were community wide as opposed to being attributable to a few taxa. Key metabolic pathways related to carbon turnover, such as cellulose degradation (∼13%) and CO2production (∼10%), and to nitrogen cycling, including denitrification (∼12%), were enriched under warming, which was consistent with independent physicochemical measurements. These community shifts were interlinked, in part, with higher primary productivity of the aboveground plant communities stimulated by warming, revealing that most of the additional, plant-derived soil carbon was likely respired by microbial activity. Warming also enriched for a higher abundance of sporulation genes and genomes with higher G+C content. Collectively, our results indicate that microbial communities of temperate grassland soils play important roles in mediating feedback responses to climate change and advance the understanding of the molecular mechanisms of community adaptation to environmental perturbations.

Soil microbial communities influencing organic phosphorus mineralization in a coastal dune chronosequence in New Zealand

2021 ◽  
Vol 97 (4) ◽  
Author(s):  
Jonathan R Gaiero ◽  
Micaela Tosi ◽  
Elizabeth Bent ◽  
Gustavo Boitt ◽  
Kamini Khosla ◽  
...  
Keyword(s):  
New Zealand ◽  
Acid Phosphatase ◽  
Microbial Communities ◽  
High Throughput Sequencing ◽  
Organic Phosphorus ◽  
Mineral Soil ◽  
Soil Microbial Communities ◽  
Organic P ◽  
Fungal Community Composition ◽  
Soil Microbial

ABSTRACT The Haast chronosequence in New Zealand is an ∼6500-year dune formation series, characterized by rapid podzol development, phosphorus (P) depletion and a decline in aboveground biomass. We examined bacterial and fungal community composition within mineral soil fractions using amplicon-based high-throughput sequencing (Illumina MiSeq). We targeted bacterial non-specific acid (class A, phoN/phoC) and alkaline (phoD) phosphomonoesterase genes and quantified specific genes and transcripts using real-time PCR. Soil bacterial diversity was greatest after 4000 years of ecosystem development and associated with an increased richness of phylotypes and a significant decline in previously dominant taxa (Firmicutes and Proteobacteria). Soil fungal communities transitioned from predominantly Basidiomycota to Ascomycota along the chronosequence and were most diverse in 290- to 392-year-old soils, coinciding with maximum tree basal area and organic P accumulation. The Bacteria:Fungi ratio decreased amid a competitive and interconnected soil community as determined by network analysis. Overall, soil microbial communities were associated with soil changes and declining P throughout pedogenesis and ecosystem succession. We identified an increased dependence on organic P mineralization, as found by the profiled acid phosphatase genes, soil acid phosphatase activity and function inference from predicted metagenomes (PICRUSt2).

scholarly journals Changes In Soil Properties Across A Hydrological Gradient In Saladas From Northeast Spain: Implications For Soil Carbon Stocks, CO2 Efflux And Microbial Communities In A Warming World.

2021 ◽  
Author(s):  
Andrew Thomas ◽  
Stephen Tooth ◽  
S. Lan ◽  
Thomas Holt ◽  
Ian Saunders ◽  
...  
Keyword(s):  
Climate Change ◽  
Microbial Communities ◽  
Soil Carbon ◽  
Soil Microbial Communities ◽  
Spatial And Temporal Variability ◽  
Co2 Efflux ◽  
Organic C ◽  
C Cycle ◽  
C Stocks ◽  
Warming World

Abstract Numerous permanent and temporary wetlands occur throughout the world’s drylands. Although characterised by diverse hydroperiods, these wetlands in drylands are typically hotspots of biological activity and productivity. The healthy functioning and possibly even existence of many wetlands in drylands, however, is threatened by desiccation resulting from a combination of climate change and human disturbance. Near Alcañiz in arid northeast Spain, three adjacent saladas (playas) with contrasting hydroperiods provide an opportunity to investigate how moisture availability affects their soil carbon (C) stocks, CO2 efflux, and microbial communities. Frequent inundation and/or near-permanent soil saturation supports the generation of organic C from a range of different sources. Soil inorganic C was greatest on the driest salada (3.8 %) compared to the wetter saladas (3.0 % and 2.1 %) owing to evaporative concentration and the reaction of CO2 with available Ca2+, Mg2+ and Na+ ions. CO2 efflux was greatest at intermediate moisture levels (142 mg CO2 m-2 hr-1), but the spatial and temporal variability in CO2 efflux on salada surfaces is very high, demonstrating the need for intensive sampling regimes to provide realistic estimates of their contribution to atmospheric CO2 exchanges. Different microbial community structures also characterise each salada. The saladas near Alcañiz, and many other similar features in northeast Spain, are renowned for their rare and threatened flora and fauna, yet their soil C cycle characteristics and soil microbial communities provide additional reasons to monitor the impacts of climate change and protect these vulnerable environments from further anthropogenic disturbances.

scholarly journals Long-Term Drought and Warming Alter Soil Bacterial and Fungal Communities in an Upland Heathland

Ecosystems ◽  
2021 ◽  
Author(s):  
Fiona M. Seaton ◽  
Sabine Reinsch ◽  
Tim Goodall ◽  
Nicola White ◽  
Davey L. Jones ◽  
...  
Keyword(s):  
Climate Change ◽  
Microbial Communities ◽  
Soil Microbial Communities ◽  
Fungal Communities ◽  
Its2 Region ◽  
Rrna Gene ◽  
Summer Drought ◽  
Soil Microbial ◽  
Soil Bacterial

AbstractThe response of soil microbial communities to a changing climate will impact global biogeochemical cycles, potentially leading to positive and negative feedbacks. However, our understanding of how soil microbial communities respond to climate change and the implications of these changes for future soil function is limited. Here, we assess the response of soil bacterial and fungal communities to long-term experimental climate change in a heathland organo-mineral soil. We analysed microbial communities using Illumina sequencing of the 16S rRNA gene and ITS2 region at two depths, from plots undergoing 4 and 18 years of in situ summer drought or warming. We also assessed the colonisation of Calluna vulgaris roots by ericoid and dark septate endophytic (DSE) fungi using microscopy after 16 years of climate treatment. We found significant changes in both the bacterial and fungal communities in response to drought and warming, likely mediated by changes in soil pH and electrical conductivity. Changes in the microbial communities were more pronounced after a longer period of climate manipulation. Additionally, the subsoil communities of the long-term warmed plots became similar to the topsoil. Ericoid mycorrhizal colonisation decreased with depth while DSEs increased; however, these trends with depth were removed by warming. We largely ascribe the observed changes in microbial communities to shifts in plant cover and subsequent feedback on soil physicochemical properties, especially pH. Our results demonstrate the importance of considering changes in soil microbial responses to climate change across different soil depths and after extended periods of time.

Sign in / Sign up

Export Citation Format

Share Document