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1.
Comput Biol Med ; 174: 108457, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599071

RESUMO

Glioma is a common malignant brain tumor with great heterogeneity and huge difference in clinical outcomes. Although lymphotoxin (LT) beta receptor (LTBR) has been linked to immune system and response development for decades, the expression and function in glioma have not been investigated. To confirm the expression profile of LTBR, integrated RNA-seq data from glioma and normal brain tissues were analyzed. Functional enrichment analysis, TMEscore analysis, immune infiltration, the correlation of LTBR with immune checkpoints and ferroptosis, and scRNAseq data analysis in gliomas were in turn performed, which pointed out that LTBR was pertinent to immune functions of macrophages in gliomas. In addition, after being trained and validated in the tissue samples of the integrated dataset, an LTBR DNA methylation-based prediction model succeeded to distinguish gliomas from non-gliomas, as well as the grades of glioma. Moreover, by virtue of the candidate LTBR CpG sites, a prognostic risk-score model was finally constructed to guide the chemotherapy, radiotherapy, and immunotherapy for glioma patients. Taken together, LTBR is closely correlated with immune functions in gliomas, and LTBR DNA methylation could serve as a biomarker for diagnosis and prognosis of gliomas.


Assuntos
Biomarcadores Tumorais , Neoplasias Encefálicas , Glioma , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Metilação de DNA/genética , Glioma/imunologia , Glioma/genética , Glioma/metabolismo
2.
Animals (Basel) ; 14(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38612367

RESUMO

Precision Livestock Farming (PLF) involves the real-time monitoring of images, sounds, and other biological, physiological, and environmental parameters to assess and improve animal health and welfare within intensive and extensive production systems [...].

3.
J Sci Food Agric ; 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38523062

RESUMO

BACKGROUND: The microbial community plays a crucial role in Chinese strong-flavor baijiu (SFB) fermentation. However, the seasonal dynamics of the microbial community in the SFB fermentation system and its contribution to the unique flavor of SFB have not been fully elucidated. In this study, we investigated the seasonal dynamics of the microbial community through 16S rRNA and ITS gene sequencing. RESULTS: The results revealed significant temporal dynamics of microbial communities and environmental variables throughout the four seasons. The influence of seasons on fungal communities was found to be more significant than on bacterial communities. The diversity of bacteria was higher during the winter and summer, whereas fungal diversity was more prominent in summer and autumn. Stochastic processes maintained their dominance in microbial assembly throughout all four seasons but the significance of heterogeneous selection increased during summer for both bacteria and fungi, whereas homogeneous selection became more pronounced during winter for fungi. The pH and environmental temperature were important drivers of microbial community assembly across different seasons, primarily impacting the core genera responsible for the production of major volatile flavor compounds (VFCs), especially ethyl caproate. CONCLUSION: These findings provide new insights into the impact of seasons on microbial communities and hold promise for improving the quality-control measures for SFB brewed in different seasons. © 2024 Society of Chemical Industry.

4.
Endocr Connect ; 12(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855388

RESUMO

Purpose: We aimed to describe and predict the risk of severe hypernatremia after surgical resection of craniopharyngioma and to identify the association of water intake, urine output, and sodium level change in the patients. Method: The outcome was postoperative severe hypernatremia. We identified risk factors associated with hypernatremia using multivariable regression. We trained machine learning models to predict the outcome. We compared serum sodium change, intravenous input, oral input, total input, urine output, and net fluid balance according to different nurse shifts. Results: Among 234 included patients, 125 developed severe hypernatremia after surgery. The peak incidence occurred during day 0 and day 6 after surgery. The risk was increased in patients with gross total resection (odds ratio (OR) 2.41, P < 0.001), high Puget classification (OR 4.44, P = 0.026), preoperative adrenal insufficiency (OR 2.01, P = 0.040), and preoperative hypernatremia (OR 5.55, P < 0.001). The random forest algorithm had the highest area under the receiver operating characteristic curve (0.770, 95% CI, 0.727-0.813) in predicting the outcome and was validated in the prospective validation cohort. Overnight shifts were associated with the highest serum sodium increase (P = 0.010), less intravenous input (P < 0.001), and less desmopressin use (P < 0.001). Conclusion: The overall incidence of severe hypernatremia after surgical resection of craniopharyngioma was significant, especially in patients with gross total resection, hypothalamus distortion, preoperative adrenal insufficiency, and preoperative severe hypernatremia. Less intravenous input and less desmopressin use were associated with serum sodium increases, especially during overnight shifts.

5.
ISME J ; 17(11): 1920-1930, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37666974

RESUMO

A major challenge in managing and engineering microbial communities is determining whether and how microbial community responses to environmental alterations can be predicted and explained, especially in microorganism-driven systems. We addressed this challenge by monitoring microbial community responses to the periodic addition of the same feedstock throughout anaerobic digestion, a typical microorganism-driven system where microorganisms degrade and transform the feedstock. The immediate and delayed response consortia were assemblages of microorganisms whose abundances significantly increased on the first or third day after feedstock addition. The immediate response consortia were more predictable than the delayed response consortia and showed a reproducible and predictable order-level composition across multiple feedstock additions. These results stood in both present (16 S rRNA gene) and potentially active (16 S rRNA) microbial communities and in different feedstocks with different biodegradability and were validated by simulation modeling. Despite substantial species variability, the immediate response consortia aligned well with the reproducible CH4 production, which was attributed to the conservation of expressed functions by the response consortia throughout anaerobic digestion, based on metatranscriptomic data analyses. The high species variability might be attributed to intraspecific competition and contribute to biodiversity maintenance and functional redundancy. Our results demonstrate reproducible and predictable microbial community responses and their importance in stabilizing system functions.


Assuntos
Microbiota , Anaerobiose , Biodiversidade , RNA Ribossômico 16S/genética , RNA Ribossômico , Reatores Biológicos , Consórcios Microbianos/genética
6.
Sci Total Environ ; 903: 166570, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37633385

RESUMO

A soil history of exposure to extreme weather may impact future plant growth and microbial community assembly. Currently, little is known about whether and how previous precipitation regime (PR)-induced changes in soil microbial communities influence plant and soil microbial community responses to a subsequent PR. We exposed grassland mesocosms to either an ambient PR (1 day wet-dry alternation) or a persistent PR (30 days consecutive wet-dry alternation) for one year. This conditioned soil was then inoculated as a 10 % fraction into 90 % sterilized "native" soil, after which new plant communities were established and subjected to either the ambient or persistent PR for 60 days. We assessed whether past persistent weather-induced changes in soil microbial community composition affect soil microbial and plant community responses to subsequent weather persistence. The historical regimes caused enduring effects on fungal communities and only temporary effects on bacterial communities, but did not trigger soil microbial legacy effects on plant productivity when exposed to either current PR. This study provides experimental evidence for soil legacy of climate persistence on grassland ecosystems in response to subsequent climate persistence, helping to understand and predict the influences of future climate change on soil biota.

8.
J Environ Manage ; 331: 117307, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36652878

RESUMO

Microorganisms in anaerobic digestion (AD) are essential for wastes/pollutants treatment and energy recovery. Due to microbial enormous diversity, developing effective perspectives to understand microbial roles therein is urgent. This study conducted AD of swine manure, used an ensemble-based network analysis to distinguish interconnected, unconnected, copresence (positively interconnected) and mutual-exclusion (negatively interconnected) microorganisms within microbial communities, and explored their importance towards AD performances, using amplicon sequencing of 16S rRNA and 16S rRNA gene. Our analyses revealed greater importance of interconnected than unconnected microorganisms towards CH4 production and AD multifunctionality, which was attributed to higher niche breadth, deterministic community assembly, community stability and phylogenetic conservatism. The diversity was higher in unconnected than interconnected microorganisms, but was not linked to AD performances. Compared to copresence microorganisms, mutual-exclusion microorganisms showed greater and equal importance towards CH4 production and AD multifunctionality, which was attributed to their roles in stabilizing microbial communities. The increased feedstock biodegradability, by replacing part of manure with fructose or apple waste, hardly affected the relative importance of interconnected versus unconnected microorganisms towards CH4 production or AD multifunctionality. Our findings develop a new framework to understand microbial roles, and have important implications in targeted manipulation of critical microorganisms in waste-treatment systems.


Assuntos
Esterco , Microbiota , Animais , Suínos , Anaerobiose , Filogenia , RNA Ribossômico 16S/genética , Metano , Reatores Biológicos , Biocombustíveis
10.
Water Res ; 226: 119307, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332298

RESUMO

Microbial life strategy, reflected by rRNA operon (rrn) copy number, determines microbial ecological roles. However, the relationship between microbial life strategy and the energy and nutrient flux in anaerobic digestion (AD) remains elusive. This study investigated microbial rrn copy number and expression ratio using amplicon sequencing of 16S rRNA gene and 16S rRNA, and monitored CH4 daily production to approximate the status of energy and nutrient flux in semi-continuous AD. A significantly positive correlation between the mean rrn copy number of microbial communities in digestate and CH4 daily production was detected in the control treatment fed swine manure. The reduced feedstock complexity, by replacing parts of swine manure with fructose or apple waste, weakened the correlation. When feedstock complexity was increased again, the correlation was strengthened again. Similar results were detected in mean rrn expression ratio of microbial communities. The responses of mean rrn copy number and expression ratio of communities to feedstock addition differed between the reduced feedstock complexity and the control treatment, as well as between in digestate and in straw. Our findings reveal a novel relationship between microbial community life strategy and the energy and nutrient flux, and the roles of feedstock characteristics therein in AD.


Assuntos
Esterco , Óperon de RNAr , Suínos , Animais , RNA Ribossômico 16S/genética , Anaerobiose , Variações do Número de Cópias de DNA , Nutrientes , Reatores Biológicos , Metano
11.
Neurol Sci ; 43(12): 6881-6888, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36083535

RESUMO

BACKGROUND: Bilateral medial medullary infarction (BMMI) is a rare type of posterior circulation stroke. The aim of this study is to characterize its stroke mechanisms, clinical manifestations, neuroradiological features, and prognosis. METHODS: From January 2015 to June 2021, a retrospective review of 15 patients diagnosed with BMMI was conducted. The clinical and neuroradiological features were summarized by our experienced neurologists. RESULTS: Fifteen patients (12 male, 3 female), ranging in age from 48 to 72 years, satisfied the inclusion criteria. The common clinical presentations included motor weakness (100%), deep sensory disturbance (93.3%), vertigo/dizziness (80%), dysarthria (93.3%), and dysphagia (66.7%). Vertically, infarct lesions in the rostral medulla were observed in all included patients. Horizontally, "heart appearance," "Y appearance," and "fan appearance" infarcts occurred in 9 cases (60%), 5 cases (33.3%), and 1 (6.7%) case, respectively. Patients (53.3%) had severe stenosis or occlusion in unilateral vertebral artery (VA), and 33.3% had normal findings in the vertebrobasilar artery. Patients (93.3%) achieved poor prognosis. CONCLUSION: BMMI is more frequently located in the rostral medulla and comprises three forms of infarction. The two main stroke etiologies of BMMI are large-artery atherosclerosis (LAA) and small vessel disease (SVD). BMMI is always associated with bad clinical outcome.


Assuntos
Imageamento por Ressonância Magnética , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Imageamento por Ressonância Magnética/efeitos adversos , Bulbo/patologia , Artéria Vertebral/patologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Infarto/complicações
12.
J Hazard Mater ; 438: 129441, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35777143

RESUMO

Anaerobic digestion (AD) is widely used to treat livestock manure that harbors diverse pollutants (resistance genes (ARGs), metal/biocide resistance genes (MBRGs), integron-integrase genes, human pathogens and pathogen virulence factors (VFs)). However, the interplays of these pollutants and the effects of substrate complexity on pollutants in AD are elusive. This study investigated the dynamics of these pollutants and bacterial communities during AD of swine manure, by metatranscriptomic sequencing and amplicon sequencing of 16 S rRNA and 16 S rRNA gene. The pollutant profiles and bacterial communities differed across AD processes, nevertheless with consistent dominance of ARGs of multi-drugs, tetracycline, aminoglycoside and rifamycin, MBRGs of multi-biocides, multi-metals, copper and arsenic, the integron-integrase gene intI1, potential pathogens of Escherichia coli, Streptococcus gallolyticus and Clostridium perfringens, VFs involved in pathogen adherence, and bacterial phyla of Firmicutes, Bacteroidetes and Proteobacteria. Reduced substrate complexity (replacing a part of swine manure, a complex substrate, with a simple substrate, apple waste or fructose) decreased the prevalence and stochastic turnover of ARGs and MBRGs. Network analyses revealed decreased interplays among pollutants under reduced substrate complexity. Our findings provide a mechanical understanding of diverse pollutants dynamics during AD, and reveal the importance of substrate complexity in controlling prevalence and interplays of pollutants.


Assuntos
Desinfetantes , Poluentes Ambientais , Anaerobiose , Animais , Antibacterianos/farmacologia , Bactérias , Desinfetantes/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos , Integrases/genética , Integrases/farmacologia , Integrons/genética , Esterco/microbiologia , Prevalência , Suínos , Fatores de Virulência/genética , Fatores de Virulência/farmacologia
13.
Animals (Basel) ; 12(9)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35565477

RESUMO

Broiler chickens exposed to heat stress adapt to various behavioral changes to regulate their comfortable body temperature, which is critical to ensure their performance and welfare. Hence, assessing various behavioral responses in birds when they are subjected to environmental changes can be essential for assessing their welfare under heat-stressed conditions. This study aimed to evaluate the effect of two air velocity (AV) treatments on heavy broilers' behavioral changes from 43 to 54 days under summer conditions. Two AV treatments (high and low) were applied in six poultry growth chambers with three chambers per treatment and 44 COBB broilers per chamber from 28 to 61 days in the summer of 2019. Three video cameras placed inside each chamber (2.44 m × 2.44 m × 2.44 m in dimension) were used to record the behavior of different undisturbed birds, such as feeding, drinking, resting, standing, walking, panting, etc. The results indicate that the number of chickens feeding, drinking, standing, walking, sitting, wing flapping, and leg stretching changed under AV treatments. High AV increased the number of chickens feeding, standing, and walking. Moreover, a two-way interaction with age and the time of day can affect drinking and panting. This study provides insights into heavy broilers' behavioral changes under heat-stressed conditions and AV treatments, which will help guide management practices to improve birds' performance and welfare under commercial conditions in the future.

14.
Biomed Res Int ; 2022: 4704107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35578722

RESUMO

Objective: To explore the effect of family participatory nursing model based on WeChat platform on psychological elasticity and life quality of patients with lung cancer. Methods: One hundred patients with lung cancer treated in our hospital from February 2019 to April 2021 were enrolled. The patients were randomly assigned into control group and study group. The control group received routine nursing and the study group received family participatory nursing model based on WeChat platform. The scores of nursing satisfaction, self-feeling burden, symptom group assessment scale, family care index, and compliance and life quality were compared. Results: First of all, we compared the nursing satisfaction: the study group was very satisfied in 25 cases, satisfactory in 20 cases, general in 5 cases, the satisfaction rate was 100.00%; the control group was very satisfied in 14 cases, satisfactory in 17 cases, general in 13 cases, dissatisfied in 6 cases, and the satisfaction rate was 88.00%. Compared between the two groups, the nursing satisfaction in the study group was higher compared to the control group (P < 0.05). Secondly, we compared the self-perceived burden, the emotional burden, physical burden, and economic burden and total scores of the study group were lower compared to the control group (P < 0.05). Comparing the scores of symptom group evaluation scale, the scores of respiratory symptoms, fatigue symptoms, psychological and emotional symptoms, digestive tract symptoms, and nervous system symptoms in the study group were lower compared to the control group (P < 0.05). In terms of the family care index of the two groups, the scores of fitness, cooperation, length, emotion, and intimacy in the study group were higher compared to the control group (P < 0.05). Comparison of compliance, the study group was very compliant in 42 cases, compliant in 7 cases, noncompliant in 1 case, the compliance rate was 98.00%; the control group was very compliant in 24 cases, compliant in 20 cases, noncompliant in 6 cases, the compliance rate was 88.00%. The compliance rate in the study group was higher compared to the control group (P < 0.05). Finally, we compared the scores of qualities of life. Before nursing, there exhibited no significant difference (P > 0.05). The scores of physiological function, psychological function, social function, and health self-cognition in the study group were lower compared to the control group (P < 0.05). Conclusion: The family participatory nursing model based on WeChat platform helps to facilitate the psychological elasticity and quality of life of patients with lung cancer and further promote patients' self-care ability and compliance with lung cancer. It can also effectively enhance family care and nursing satisfaction; the nursing model is worth popularizing and applying in clinic.


Assuntos
Neoplasias Pulmonares , Qualidade de Vida , Elasticidade , Humanos , Modelos de Enfermagem , Cooperação do Paciente
15.
Environ Microbiol ; 24(9): 3985-4000, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35238127

RESUMO

The mechanisms underlying microbial community dynamics and co-occurrence patterns along ecological succession are crucial for understanding ecosystem recovery but remain largely unexplored. Here, we investigated community dynamics and taxa co-occurrence patterns in bacterial and fungal communities across a well-established chronosequence of post-mining lands spanning 54 years of recovery. Bacterial community structures became increasingly phylogenetically clustered with soil age at early successional stages and varied less at later successional stages. The dynamics of bacterial community phylogenetic structures were determined by the changes in the soil vegetation cover along succession. The dynamics of fungal community phylogenetic structures did not significantly correlate with soil age, soil properties or vegetation cover, and were mainly attributed to stochastic processes. Along succession, the common decrease in the bacterial co-occurrence complexity and in the average pairwise phylogenetic distances between co-occurring bacteria implied a decrease in potential bacterial cooperation. The increased complexity of fungal co-occurrence along succession was independent of phylogenetic relatedness between co-occurring fungi. This study provides new sights into ecological mechanisms underlying bacterial and fungal community succession.


Assuntos
Ecossistema , Micobioma , Bactérias/genética , Micobioma/genética , Filogenia , Solo/química , Microbiologia do Solo
16.
Animals (Basel) ; 12(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35158651

RESUMO

Heavy broilers exposed to hot summer conditions experience fluctuations in surface temperatures due to heat stress, which leads to decreased performance. Maintaining a bird's homeostasis depends on several environmental factors (temperature, relative humidity, and air velocity). It is important to understand the responses of birds to environmental factors and the amount of heat loss to the surrounding environment to create thermal comfort for the heavy broilers for improved performances and welfare. This study investigates the variation in surface temperatures of heavy broilers under high and low air velocity treatments. Daytime, age and bird location's effect on the surface temperature variation was also examined. The experiment was carried out in the poultry engineering laboratory of North Carolina State University during summers of 2017, 2018, and 2019 as a part of a comprehensive study on the effectiveness of wind chill application to mitigate heat stress on heavy broilers. This live broiler heat stress experiment was conducted under two dynamic air velocity treatments (high and low) with three chambers per treatment and 44 birds per chamber. Surface temperatures of the birds were recorded periodically through the experimental treatment cycles (flocks, 35-61 d) with infrared thermography in the morning, noon, evening, and nighttime. The overall mean surface temperature of the broilers under two treatments was found to be 35.89 ± 2.37 °C. The variation in surface temperature happened due to air temperature, thermal index, air velocity, bird's age, daytime, and position of birds inside the experimental chambers. The surface temperatures were found lower under high air velocity treatment and higher under low air velocity treatment. During the afternoon time, the broilers' surface temperatures were higher than other times of the day. It was also found that the birds' surface temperature increased with age and temperature humidity indices. Based upon the experimental data of five flocks, a simple linear regression model was developed to predict surface temperature from the birds' age, thermal indices, and air velocity. It will help assess heavy broilers' thermal comfort under heat stress, which is essential to provide a comfortable environment for them.

17.
Bioresour Technol ; 344(Pt B): 126243, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34737136

RESUMO

The mechanisms underlying the advanced performance in anaerobic co-digestion (AcoD) are crucial but remain elusive. This study conducted AcoD of swine manure, rice straw and apple waste (AW, mainly consisting of labile carbon) or fructose (a pure labile carbon), and monitored microbial community abundances, activities and transcriptional profiles in the digestate and on straw. The transformation efficiencies of manure (not straw) to CH4 were promoted in AcoD co-fed manure and AW (by 39 ± 13%) or fructose (by 65 ± 14%), compared to the control mono-fed manure, implying labile carbon could trigger a priming effect underlying AcoD advantage. Although digestate-associated and straw-associated communities existed in a same bioreactor, the priming effect mainly linked to the former and was attributed to enhancements in deterministic turnover of active communities, in activities of Firmicutes taxa involved in substrate hydrolysis, and in acetoclastic methanogenesis. These findings provide novel insights to elaborate AcoD processes.


Assuntos
Biocombustíveis , Metano , Anaerobiose , Animais , Carbono , Esterco , Suínos
18.
Environ Res ; 204(Pt B): 112064, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34534519

RESUMO

This study investigated the physicochemical properties of the particles in a typical commercial laying hen barn in Southeast China. Mass concentrations and size distributions of the particulate matter (PM) and the key components (incl. organic carbon (OC), element carbon (EC), and the water-soluble inorganic ions (WSIIs)) were analyzed. The result shows that the mass concentrations of PM accumulated along with the airflow inside the house, with the total mass of the sampling particles increasing from 843.66 ± 160.74 µg/m3 at the center of the house to 1264.93 ± 285.70 µg/m3 at the place close to exhaust fans. The particles with the aerodynamic equivalent diameter, Dp > 9 µm, coarse particles (2.1 µm < Dp ≤ 9 µm), fine particles (Dp ≤ 2.1 µm) accounted for around 50%, 40%, and 10% of the total mass of the sampling particles, respectively. Mass closure analysis shows secondary inorganic ions (NH4+, SO42- and NO3-) were abundant in the fine-mode fraction and OC accounted for more than 40% of the coarse particles. Size distribution analysis shows that the three secondary inorganic ions were bimodally distributed, and the rest tested components were unimodally distributed. The ratios of OC/EC in fine particles were smaller than those in the coarse particles. The equivalent concentration of WSIIs indicated that fine particles were slightly acidic, and the large size particles were slightly alkaline. Knowledge gained from this study will lead to a better understanding of physicochemical properties, sources, and formation of PM.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Animais , Galinhas , China , Monitoramento Ambiental , Feminino , Tamanho da Partícula , Material Particulado/análise , Estações do Ano
19.
FEMS Microbiol Ecol ; 97(9)2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34379756

RESUMO

Global climate changes such as prolonged duration and intensity of drought can lead to adverse ecological consequences in forests. Currently little is known about soil microbial community responses to such drought regimes in tropical forests. In this study, we examined the resistance and resilience of topsoil prokaryotic communities to a prolongation of the dry season in terms of diversity, community structure and co-occurrence patterns in a French Guianan tropical forest. Through excluding rainfall during and after the dry season, a simulated prolongation of the dry season by five months was compared to controls. Our results show that prokaryotic communities increasingly diverged from controls with the progression of rain exclusion. Furthermore, prolonged drought significantly affected microbial co-occurrence networks. However, both the composition and co-occurrence networks of soil prokaryotic communities immediately ceased to differ from controls when precipitation throughfall returned. This study thus suggests modest resistance but high resilience of microbial communities to a prolonged drought in tropical rainforest soils.


Assuntos
Secas , Solo , Florestas , Chuva , Microbiologia do Solo , Árvores , Clima Tropical
20.
Environ Sci Pollut Res Int ; 28(47): 67748-67763, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34259991

RESUMO

Uncertainty regarding how subalpine forest ecosystems respond to tree harvesting hinders their sustainable management and conservation strategies. To investigate the impact of oak (Quercus aquifolioides Rehd. et Wils.) harvesting and stand recovery processes on soil microbial communities and understory vegetation on the eastern Tibetan Plateau, we sampled and quantified the microbial community structure and understory vegetation in three age classes (1 year, 10 years, and 20 years since tree logging) of harvested stands and an un-harvested reference (control) stand of subalpine oak forest. Our result showed logging significantly altered the edaphic properties (p < 0.001) and shifted microbial community structure (p < 0.05), increasing the abundances of the Actinobacteria and arbuscular mycorrhizal fungi (AMF) but decreasing fungi and general, gram-positive and gram-negative bacteria. Post-harvest evolution increased the biomass of understory vegetation and reshaped its community. Fungi (18:1ω7c, 18:1ω9c) and gram-negative bacteria (18:2ω7c, cy19:0) abundances changed significantly (p < 0.01) after harvesting and during stand recovery, suggesting their potential use as indicators for post-harvest oak recovery. Structural equation modeling (SEqM) revealed that, via litter, residue, and edaphic properties, the recovery process indirectly promoted microbe abundance while the overstory vegetation regrowth inhibited the plant community's biomass in the understory. Microbial communities only had a minor, direct effect on understory vegetation. Litter and edaphic factors played important roles in reshaping understory plant and soil microbial communities for post-harvest evolution.


Assuntos
Micorrizas , Quercus , Antibacterianos , Ecossistema , Florestas , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Solo , Microbiologia do Solo , Tibet
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