Commonwealth of Soil Health: How Do Earthworms Modify the Soil Microbial Responses to CeO2 Nanoparticles?

The role of microbial communities in maintaining soil health is mostly influenced by chemical condition of soil. Microbial communities vary in response to soil chemical factors. The contradictive results from previous findings emphasise that it is difficult to define a pattern of the influence of soil chemical factors on soil microbial diversity and activity. The aim of the study was to assess soil microbial responses to soil chemical factors in agricultural soils. Composite soil (Dermosol order) samples taken from 16 commercial crop sites in Bundaberg, Queensland, Australia, were chemically and biologically analysed. It was found that bacterial and fungal activity and diversity were significantly affected by soil EC, SOM and NO3-N content, but were not influenced by soil pH, CEC, and Ca:Mg ratio. The diversity of bacterial and fungal communities displayed a positive linear relationship with soil EC, whereas the activity and diversity of these two microbial groups and SOM displayed a significant quadratic relationship. The finding suggested that microbial community was predominantly influenced by SOM content.

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Early Spring Snowmelt and Summer Droughts Strongly Impair the Resilience of Key Microbial Communities in Subalpine Grassland Ecosystems

10.1101/2021.03.15.435477 ◽

2021 ◽

Author(s):

Farhan Hafeez ◽

Lionel Bernard ◽

Jean-Christophe Clement ◽

Franck Poly ◽

Thomas Pommier

Keyword(s):

Microbial Communities ◽

Plant Biomass ◽

Early Spring ◽

Climatic Extremes ◽

Soil Microbial ◽

Cascading Effect ◽

Growing Seasons ◽

Grassland Ecosystems ◽

Microbial Responses ◽

Early Snowmelt

Subalpine grassland ecosystems are important from biodiversity, agriculture, and touristic perspectives but their resilience to seasonally occurring climatic extremes is increasingly challenged with climate change, accelerating their vulnerability to tipping points. Microbial communities, which are central in ecosystem functioning, are usually considered as more resistant and highly resilient to such extreme events due to their functional redundancy and strong selection in residing habitats. To investigate this, we explored the soil microbial responses upon recurrent summer droughts associated with early snowmelt in grasslands mesocosms set-up at the Lautaret Pass (French Alps). Potential respiration, nitrification and denitrification were monitored over a period of two growing seasons along with quantification of community gene abundances of total bacteria as well as (de)nitrifiers. Results revealed that droughts had a low and short-term impact on bacterial total respiration supporting their hypothesized high resistance and ability to recover. Nitrification and abundances of the corresponding functional guilds showed relatively strong resistance to summer droughts but declined in response to early snowmelt. This triggered a cascading effect on denitrification but also on the abundances of denitrifying communities which could recover from all climatic extremes except from the summer droughts where nitrifiers were collapsed. Denitrification and the respective functional groups faced high impact of applied stresses with strong reduction in the abundance and activity of this specialized community. Although, the consequently lower microbial competition for nitrate may be positive for plant biomass production, warnings exist when considering the potential nitrogen leaching from these ecosystems as well as risks of greenhouses gases emission such as N2O

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Identification and characterization of proteins, lipids, and metabolites in two organic fertilizer products derived from different nutrient sources

Applied Biological Chemistry ◽

10.1186/s13765-021-00625-2 ◽

2021 ◽

Vol 64 (1) ◽

Author(s):

Jianyu Li ◽

Xin Zhao ◽

Laura S. Bailey ◽

Manasi N. Kamat ◽

Kari B. Basso

Keyword(s):

Biochemical Composition ◽

Organic Fertilizer ◽

Saturated Fatty Acids ◽

Soil Health ◽

Soil Microbial Communities ◽

Organic Fertilizers ◽

Vegetable Production ◽

Limited Information ◽

Nutrient Sources ◽

Soil Microbial

AbstractThe biochemical composition of organic fertilizers largely determines their nutrient supply characteristics following soil application as well as their potential impact on soil microbial communities. Yet, limited information is available regarding the biochemical composition of organic fertilizers derived from different nutrient sources. Here, we qualitatively analyzed the presence and abundance of proteins, lipids, and metabolites in a liquid fish fertilizer (LFF) product and a type of granular organic fertilizer (GOF) commonly used in organic vegetable production, using liquid chromatography–tandem mass spectrometry (LC–MS/MS). Our results suggest that the presence and abundance of proteins, lipids, and metabolites differ greatly between GOF and LFF. The qualitative analysis shows LFF as a rich source of metabolites, while complex proteins and long-chain saturated fatty acids are dominant in GOF. The degree of biochemical composition complexity may help explain the varying impacts of different types of organic fertilizers on nutrient availability, soil health, and environmental quality.

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Resilience and Assemblage of Soil Microbiome in Response to Chemical Contamination Combined with Plant Growth

Applied and Environmental Microbiology ◽

10.1128/aem.02523-18 ◽

2019 ◽

Vol 85 (6) ◽

Cited By ~ 5

Author(s):

Shuo Jiao ◽

Weimin Chen ◽

Gehong Wei

Keyword(s):

Microbial Communities ◽

Soil Microbial Communities ◽

Soil Microbiome ◽

Chemical Contamination ◽

Plant Interactions ◽

Soil Microbial Diversity ◽

Soil Microbial ◽

Microbial Responses ◽

Legume Plants ◽

Functional Profiles

ABSTRACT A lack of knowledge of the microbial responses to environmental change at the species and functional levels hinders our ability to understand the intrinsic mechanisms underlying the maintenance of microbial ecosystems. Here, we present results from temporal microcosms that introduced inorganic and organic contaminants into agro-soils for 90 days, with three common legume plants. Temporal dynamics and assemblage of soil microbial communities and functions in response to contamination under the influence of growth of different plants were explored via sequencing of the 16S rRNA amplicon and by shotgun metagenomics. Soil microbial alpha diversity and structure at the taxonomic and functional levels exhibited resilience patterns. Functional profiles showed greater resilience than did taxonomic ones. Different legume plants imposed stronger selection on taxonomic profiles than on functional ones. Network and random forest analyses revealed that the functional potential of soil microbial communities was fostered by various taxonomic groups. Betaproteobacteria were important predictors of key functional traits such as amino acid metabolism, nucleic acid metabolism, and hydrocarbon degradation. Our study reveals the strong resilience of the soil microbiome to chemical contamination and sensitive responses of taxonomic rather than functional profiles to selection processes induced by different legume plants. This is pivotal to develop approaches and policies for the protection of soil microbial diversity and functions in agro-ecosystems with different response strategies from global environmental drivers, such as soil contamination and plant invasion. IMPORTANCE Exploring the microbial responses to environmental disturbances is a central issue in microbial ecology. Understanding the dynamic responses of soil microbial communities to chemical contamination and the microbe-soil-plant interactions is essential for forecasting the long-term changes in soil ecosystems. Nevertheless, few studies have applied multi-omics approaches to assess the microbial responses to soil contamination and the microbe-soil-plant interactions at the taxonomic and functional levels simultaneously. Our study reveals clear succession and resilience patterns of soil microbial diversity and structure in response to chemical contamination. Different legume plants exerted stronger selection processes on taxonomic than on functional profiles in contaminated soils, which could benefit plant growth and fitness as well as foster the potential abilities of hydrocarbon degradation and metal tolerance. These results provide new insight into the resilience and assemblage of soil microbiome in response to environmental disturbances in agro-ecosystems at the species and functional levels.

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Impact of Agri-Usable Nanocompounds on Soil Microbial Activity: An Indicator of Soil Health

CLEAN - Soil Air Water ◽

10.1002/clen.201600458 ◽

2017 ◽

Vol 45 (5) ◽

pp. 1600458 ◽

Cited By ~ 6

Author(s):

Priyanka Khati ◽

Anita Sharma ◽

Saurabh Gangola ◽

Rajeew Kumar ◽

Pankaj Bhatt ◽

...

Keyword(s):

Microbial Activity ◽

Soil Health ◽

Soil Microbial Activity ◽

Soil Microbial

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Root renovation: how an improved understanding of basic root biology could inform the development of elite crops that foster sustainable soil health

Functional Plant Biology ◽

10.1071/fp18200 ◽

2019 ◽

Vol 46 (7) ◽

pp. 597 ◽

Cited By ~ 1

Author(s):

Johanna W.-H. Wong ◽

Jonathan M. Plett

Keyword(s):

Management Practices ◽

Agricultural Research ◽

Soil Health ◽

Value Added ◽

Soil Management ◽

Breeding Strategy ◽

Microbial Interactions ◽

Crop Species ◽

Soil Microbial ◽

Microbial Association

A major goal in agricultural research is to develop ‘elite’ crops with stronger, resilient root systems. Within this context, breeding practices have focussed on developing plant varieties that are, primarily, able to withstand pathogen attack and, secondarily, able to maximise plant productivity. Although great strides towards breeding disease-tolerant or -resistant root stocks have been made, this has come at a cost. Emerging studies in certain crop species suggest that domestication of crops, together with soil management practices aimed at improving plant yield, may hinder beneficial soil microbial association or reduce microbial diversity in soil. To achieve more sustainable management of agricultural lands, we must not only shift our soil management practices but also our breeding strategy to include contributions from beneficial microbes. For this latter point, we need to advance our understanding of how plants communicate with, and are able to differentiate between, microbes of different lifestyles. Here, we present a review of the key findings on belowground plant–microbial interactions that have been made over the past decade, with a specific focus on how plants and microbes communicate. We also discuss the currently unresolved questions in this area, and propose plausible ways to use currently available research and integrate fast-emerging ‘-omics’ technologies to tackle these questions. Combining past and developing research will enable the development of new crop varieties that will have new, value-added phenotypes belowground.

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Do diverse mixtures of cover crop residues alter the soil microbial community and increase soil function?

10.5194/egusphere-egu2020-1499 ◽

2020 ◽

Author(s):

Xin Shu ◽

Yiran Zou ◽

Liz Shaw ◽

Lindsay Todman ◽

Mark Tibbett ◽

...

Keyword(s):

Microbial Community ◽

Soil Respiration ◽

Cover Crops ◽

Soil Microbial Community ◽

Cover Crop ◽

Crop Residues ◽

Soil Health ◽

Soil Function ◽

Soil Microbial ◽

Quaternary Mixture

Cover crops are a contemporary tool to sustainably manage agricultural soils by boosting fertility, suppressing weeds and disease, and benefiting cash crop yields, thus securing future food supply. Due to the different chemical composition of crop residues from different plant families, we hypothesised that a mixture of cover crop residues may have a greater potential to improve soil health than the sum of the parts. Our experiment focused on the impact of four cover crops (clover, sunflower, radish and buckwheat) and their quaternary mixture on soil respiration and the soil microbial community in an 84-day microcosm experiment. On average adding cover crop residues significantly (P < 0.001) increased soil respiration from 29 to 343 &#181;g C g-1 h-1 and microbial biomass from 18 to 60 &#181;g C g-1, compared to the unamended control during 84 days&#8217; incubation. Cover crop addition resulted in a significant (P < 0.001) alteration of the soil microbial community structure compared to that of the control. The quaternary mixture of cover crop residues significantly (P = 0.011) increased soil respiration rate by 23.79 &#181;g C g-1 h-1 during the period 30 to 84 days after residue incorporation, compared to the average of the four individual residues. However, no significant difference in the size of the microbial biomass was found between the mixture and the average of the four individuals, indicating the mixture may invest resources which transit dormant microbial species into a metabolically active state and thus boost microbial respiration. Analysis of similarity of microbial community composition (ANOSIM) demonstrated the mixture significantly (P = 0.001) shifted microbial community structure away from buckwheat (R = 0.847), clover (R = 0.688), radish (R = 0.285) and sunflower (R = 0.785), respectively. This implies cover crop residues provide a niche specialization and differentiation on a selection of microbial communities that favour certain plant compounds. While applying cover crop residues has positive impacts on soil function, we found that applying a mixture of cover crop residues may provide greater potential to select for microorganisms or activate dormant microbial species which result in higher soil function. The outcome of this study will help seed suppliers to design, and farmers to select, novel cover crop mixtures which enhance soil function synergistically, leading to a greater potential to sustainably improve soil health.

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Annual Removal of Aboveground Plant Biomass Alters Soil Microbial Responses to Warming

mBio ◽

10.1128/mbio.00976-16 ◽

2016 ◽

Vol 7 (5) ◽

Cited By ~ 11

Author(s):

Kai Xue ◽

Mengting M. Yuan ◽

Jianping Xie ◽

Dejun Li ◽

Yujia Qin ◽

...

Keyword(s):

Nitrogen Fixation ◽

Soil Carbon ◽

Plant Biomass ◽

Biofuel Production ◽

Interactive Effects ◽

Functional Genes ◽

Soil Microbial ◽

Recalcitrant Carbon ◽

Microbial Responses

ABSTRACT Clipping (i.e., harvesting aboveground plant biomass) is common in agriculture and for bioenergy production. However, microbial responses to clipping in the context of climate warming are poorly understood. We investigated the interactive effects of grassland warming and clipping on soil properties and plant and microbial communities, in particular, on microbial functional genes. Clipping alone did not change the plant biomass production, but warming and clipping combined increased the C 4 peak biomass by 47% and belowground net primary production by 110%. Clipping alone and in combination with warming decreased the soil carbon input from litter by 81% and 75%, respectively. With less carbon input, the abundances of genes involved in degrading relatively recalcitrant carbon increased by 38% to 137% in response to either clipping or the combined treatment, which could weaken long-term soil carbon stability and trigger positive feedback with respect to warming. Clipping alone also increased the abundance of genes for nitrogen fixation, mineralization, and denitrification by 32% to 39%. Such potentially stimulated nitrogen fixation could help compensate for the 20% decline in soil ammonium levels caused by clipping alone and could contribute to unchanged plant biomass levels. Moreover, clipping tended to interact antagonistically with warming, especially with respect to effects on nitrogen cycling genes, demonstrating that single-factor studies cannot predict multifactorial changes. These results revealed that clipping alone or in combination with warming altered soil and plant properties as well as the abundance and structure of soil microbial functional genes. Aboveground biomass removal for biofuel production needs to be reconsidered, as the long-term soil carbon stability may be weakened. IMPORTANCE Global change involves simultaneous alterations, including those caused by climate warming and land management practices (e.g., clipping). Data on the interactive effects of warming and clipping on ecosystems remain elusive, particularly in microbial ecology. This study found that clipping alters microbial responses to warming and demonstrated the effects of antagonistic interactions between clipping and warming on microbial functional genes. Clipping alone or combined with warming enriched genes degrading relatively recalcitrant carbon, likely reflecting the decreased quantity of soil carbon input from litter, which could weaken long-term soil C stability and trigger positive warming feedback. These results have important implications in assessing and predicting the consequences of global climate change and indicate that the removal of aboveground biomass for biofuel production may need to be reconsidered.

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