Ontology highlight
ABSTRACT:
PROVIDER: PRJNA510676 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR8351300_1.fastq.gz | Fastqsanger.gz | |||
| SRR8351300_2.fastq.gz | Fastqsanger.gz | |||
| SRR8351297_1.fastq.gz | Fastqsanger.gz | |||
| SRR8351297_2.fastq.gz | Fastqsanger.gz | |||
| SRR8351298_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 8 |
Similar Datasets
Project description:This study explores the use of short settling times as a strategy to enhance microbial selection and prevent bulking induced by nutrient shortage in an aerobic dynamic feeding (ADF) process using mixed microbial cultures (MMCs) for polyhydroxyalkanoate (PHA) production from fermentation digestate. A 5.0-L aerobic reactor was operated under three conditions: Long Settling (LS, 30 minutes), Short Settling (SS, 10 minutes), and Short Settling under Nutrient Shortage (SS-NS, 10 minutes with reduced nutrient load). Short settling significantly improved biomass settleability, reducing the Sludge Volume Index (SVI) from 126 to 25 mL g⁻¹, and promoted the formation of dense flocs enriched in PHA-accumulating bacteria, as confirmed by transmission electron microscopy. Process kinetics revealed enhanced substrate uptake rates and improved storage yields under SS conditions, despite an elevated C/P ratio. Notably, nutrient shortage conditions were inadvertently reached by the proliferation of Polytoma mirum in the feeding tank. Although Polytoma mirum did not affect VFA composition, its presence significantly reduced nitrogen and phosphorus concentrations. These nutrient shortage conditions were maintained for at least 30 days until the system began to exhibit stress, as demonstrated by an increased SVI (178.6 mL g⁻¹). Microbial community analyses indicated marked shifts: the eukaryotic assemblage transitioned from sessile to motile ciliates under SS, while bacterial diversity within the PHA‐accumulating fraction remained high, with key taxa such as Sphaerotilus and Neomegalonema becoming more prevalent under phosphorus-limited conditions. Overall, short settling not only improved microbial selection but also prevented bulking by retaining well-aggregated biomass, thereby mitigating nutrient shortage conditions.
2025-07-24 | GSE303500 | GEO
Project description:This study explores the use of short settling times as a strategy to enhance microbial selection and prevent bulking induced by nutrient shortage in an aerobic dynamic feeding (ADF) process using mixed microbial cultures (MMCs) for polyhydroxyalkanoate (PHA) production from fermentation digestate. A 5.0-L aerobic reactor was operated under three conditions: Long Settling (LS, 30 minutes), Short Settling (SS, 10 minutes), and Short Settling under Nutrient Shortage (SS-NS, 10 minutes with reduced nutrient load). Short settling significantly improved biomass settleability, reducing the Sludge Volume Index (SVI) from 126 to 25 mL g⁻¹, and promoted the formation of dense flocs enriched in PHA-accumulating bacteria, as confirmed by transmission electron microscopy. Process kinetics revealed enhanced substrate uptake rates and improved storage yields under SS conditions, despite an elevated C/P ratio. Notably, nutrient shortage conditions were inadvertently reached by the proliferation of Polytoma mirum in the feeding tank. Although Polytoma mirum did not affect VFA composition, its presence significantly reduced nitrogen and phosphorus concentrations. These nutrient shortage conditions were maintained for at least 30 days until the system began to exhibit stress, as demonstrated by an increased SVI (178.6 mL g⁻¹). Microbial community analyses indicated marked shifts: the eukaryotic assemblage transitioned from sessile to motile ciliates under SS, while bacterial diversity within the PHA‐accumulating fraction remained high, with key taxa such as Sphaerotilus and Neomegalonema becoming more prevalent under phosphorus-limited conditions. Overall, short settling not only improved microbial selection but also prevented bulking by retaining well-aggregated biomass, thereby mitigating nutrient shortage conditions.
2025-07-24 | GSE303499 | GEO
Project description:This study explores the use of short settling times as a strategy to enhance microbial selection and prevent bulking induced by nutrient shortage in an aerobic dynamic feeding (ADF) process using mixed microbial cultures (MMCs) for polyhydroxyalkanoate (PHA) production from fermentation digestate. A 5.0-L aerobic reactor was operated under three conditions: Long Settling (LS, 30 minutes), Short Settling (SS, 10 minutes), and Short Settling under Nutrient Shortage (SS-NS, 10 minutes with reduced nutrient load). Short settling significantly improved biomass settleability, reducing the Sludge Volume Index (SVI) from 126 to 25 mL g⁻¹, and promoted the formation of dense flocs enriched in PHA-accumulating bacteria, as confirmed by transmission electron microscopy. Process kinetics revealed enhanced substrate uptake rates and improved storage yields under SS conditions, despite an elevated C/P ratio. Notably, nutrient shortage conditions were inadvertently reached by the proliferation of Polytoma mirum in the feeding tank. Although Polytoma mirum did not affect VFA composition, its presence significantly reduced nitrogen and phosphorus concentrations. These nutrient shortage conditions were maintained for at least 30 days until the system began to exhibit stress, as demonstrated by an increased SVI (178.6 mL g⁻¹). Microbial community analyses indicated marked shifts: the eukaryotic assemblage transitioned from sessile to motile ciliates under SS, while bacterial diversity within the PHA‐accumulating fraction remained high, with key taxa such as Sphaerotilus and Neomegalonema becoming more prevalent under phosphorus-limited conditions. Overall, short settling not only improved microbial selection but also prevented bulking by retaining well-aggregated biomass, thereby mitigating nutrient shortage conditions.
2025-07-24 | GSE303497 | GEO
Project description:To study whether and how soil nitrogen conditions affect the ecological effects of long-term elevated CO2 on microbial community and soil ecoprocess, here we investigated soil microbial community in a grassland ecosystem subjected to ambient CO2 (aCO2, 368 ppm), elevated CO2 (eCO2, 560 ppm), ambient nitrogen deposition (aN) or elevated nitrogen deposition (eN) treatments for a decade. Under the aN condition, a majority of microbial function genes, as measured by GeoChip 4.0, were increased in relative abundance or remained unchanged by eCO2. Under the eN condition, most of functional genes associated with carbon, nitrogen and sulfur cycling, energy processes, organic remediation and stress responses were decreased or remained unchanged by eCO2, while genes associated with antibiotics and metal resistance were increased. The eCO2 effects on fungi and archaea were largely similar under both nitrogen conditions, but differed substantially for bacteria. Coupling of microbial carbon or nitrogen cycling genes, represented by positive percentage and density of gene interaction in association networks, was higher under the aN condition. In accordance, changes of soil CO2 flux, net N mineralization, ammonification and nitrification was higher under the aN condition. Collectively, these results demonstrated that eCO2 effects are contingent on nitrogen conditions, underscoring the difficulty toward predictive modeling of soil ecosystem and ecoprocesses under future climate scenarios and necessitating more detailed studies.
2015-04-03 | GSE67531 | GEO
Project description:To study whether and how soil nitrogen conditions affect the ecological effects of long-term elevated CO2 on microbial community and soil ecoprocess, here we investigated soil microbial community in a grassland ecosystem subjected to ambient CO2 (aCO2, 368 ppm), elevated CO2 (eCO2, 560 ppm), ambient nitrogen deposition (aN) or elevated nitrogen deposition (eN) treatments for a decade. Under the aN condition, a majority of microbial function genes, as measured by GeoChip 4.0, were increased in relative abundance or remained unchanged by eCO2. Under the eN condition, most of functional genes associated with carbon, nitrogen and sulfur cycling, energy processes, organic remediation and stress responses were decreased or remained unchanged by eCO2, while genes associated with antibiotics and metal resistance were increased. The eCO2 effects on fungi and archaea were largely similar under both nitrogen conditions, but differed substantially for bacteria. Coupling of microbial carbon or nitrogen cycling genes, represented by positive percentage and density of gene interaction in association networks, was higher under the aN condition. In accordance, changes of soil CO2 flux, net N mineralization, ammonification and nitrification was higher under the aN condition. Collectively, these results demonstrated that eCO2 effects are contingent on nitrogen conditions, underscoring the difficulty toward predictive modeling of soil ecosystem and ecoprocesses under future climate scenarios and necessitating more detailed studies. Fourty eight samples were collected for four different carbon and nitrogen treatment levels (aCaN,eCaN,aCeN and eCeN) ; Twelve replicates in every elevation
2015-04-03 | E-GEOD-67531 | biostudies-arrayexpress
Project description:Salt marshes provide many key ecosystem services that have tremendous ecological and economic value. One critical service is the removal of fixed nitrogen from coastal waters, which limits the negative effects of eutrophication resulting from increased nutrient supply. Nutrient enrichment of salt marsh sediments results in higher rates of nitrogen cycling and, commonly, a concurrent increase in the flux of nitrous oxide, an important greenhouse gas. Little is known, however, regarding controls on the microbial communities that contribute to nitrous oxide fluxes in marsh sediments. To address this disconnect, we generated microbial community profiles as well as directly assayed nitrogen cycling genes that encode the enzymes responsible for overall nitrous oxide flux from salt marsh sediments. We hypothesized that communities of microbes responsible for nitrogen transformations will be structured by nitrogen availability. Taxa that respond positively to high nitrogen inputs may be responsible for the elevated rates of nitrogen cycling processes measured in fertilized sediments. Our data show that, with the exception of ammonia-oxidizing archaea, the community composition of organisms responsible for production and consumption of nitrous oxide was altered under nutrient enrichment. These results suggest that elevated rates of nitrous oxide production and consumption are the result of changes in community structure, not simply changes in microbial activity.
2018-01-13 | GSE108888 | GEO
Project description:To study long-term elevated CO2 and enriched N deposition interactive effects on microbial community and soil ecoprocess, here we investigated soil microbial community in a grassland ecosystem subjected to ambient CO2 (aCO2, 368 ppm), elevated CO2 (eCO2, 560 ppm), ambient nitrogen deposition (aN) or elevated nitrogen deposition (eN) treatments for a decade. There exist antagonistic CO2×N interactions on microbial functional genes associated with C, N, P S cycling processes. More strong antagonistic CO2×N interactions are observed on C degradation genes than other genes. Remarkably antagonistic CO2×N interactions on soil microbial communities could enhance soil C accumulation.
2018-05-01 | GSE98512 | GEO
Project description:Soil transplant serves as a proxy to simulate climate change in realistic climate regimes. Here, we assessed the effects of climate warming and cooling on soil microbial communities, which are key drivers in EarthM-bM-^@M-^Ys biogeochemical cycles, four years after soil transplant over large transects from northern (N site) to central (NC site) and southern China (NS site) and vice versa. Four years after soil transplant, soil nitrogen components, microbial biomass, community phylogenetic and functional structures were altered. Microbial functional diversity, measured by a metagenomic tool named GeoChip, and phylogenetic diversity are increased with temperature, while microbial biomass were similar or decreased. Nevertheless, the effects of climate change was overridden by maize cropping, underscoring the need to disentangle them in research. Mantel tests and canonical correspondence analysis (CCA) demonstrated that vegetation, climatic factors (e.g., temperature and precipitation), soil nitrogen components and CO2 efflux were significantly correlated to the microbial community composition. Further investigation unveiled strong correlations between carbon cycling genes and CO2 efflux in bare soil but not cropped soil, and between nitrogen cycling genes and nitrification, which provides mechanistic understanding of these microbe-mediated processes and empowers an interesting possibility of incorporating bacterial gene abundance in greenhouse gas emission modeling. Fifty four samples were collected from three soil types (Phaeozem,Cambisol,Acrisol) in three sites (Hailun, Fengqiu and Yingtan) along a latitude with reciprocal transplant; Both with and without maize cropping in each site; Three replicates in every treatments.
2013-10-30 | E-GEOD-51592 | biostudies-arrayexpress