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1.
Artigo em Inglês | MEDLINE | ID: mdl-38532216

RESUMO

This manuscript presents a scientometric review of recent advances in microwave pretreatment processes for sewage sludge, systematically identifying existing gaps and prospects. For this purpose, 1763 papers on the application of microwave technology to sludge pretreatment were retrieved from the Web of Science (WoS) using relevant keywords. These publications were then analyzed using diverse scientometric indices. The results show that research in this field encompasses applications based on the non-thermal effects of microwaves, enhanced effectiveness of anaerobic digestion (AD), and the energy balance of this pretreatment system. Overcoming existing technical challenges, such as the cleavage of extracellular polymers, reducing microwave energy consumption, understanding the non-thermal effects of microwaves, promoting AD of sludge in combination with other chemical and physical methods, and expanding the application of the technology, are the main scientific focuses. Additionally, this paper thoroughly examines both the constraints and potential of microwave pretreatment technology for wastewater treatment.

2.
Biol Trace Elem Res ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37857990

RESUMO

Previous studies on the relationship between zinc and metabolic syndrome (MetS) have yielded inconsistent results. This comprehensive study aimed to elaborately explore the impact of zinc on MetS risk factors. The bi-directional Mendelian randomization (MR) analyses were performed to estimate the causal relationship between zinc and MetS risk factors. Additionally, a retrospective cross-sectional study incorporated 4389 subjects to provide a broader perspective in conjunction with the MR analyses. In the MR analyses, genetically instrumented zinc was positively associated with five of the MetS components in Europeans, including BMI, FBG, HbA1c, TC, and LDL-c (ß (95%CI) = 0.023 (0.019-0.027), 0.019 (0.013-0.025), 0.041 (0.022-0.060), 0.027 (0.013-0.042), and 0.018 (0.010-0.026), respectively). In the cross-sectional study, higher concentration of zinc was strongly associated with increased BMI, LDL-c, and UA (ß (95%CI) = 0.040 (0.010-0.085), 0.026 (0.018-0.035), and 1.529 (0.614-2.445), respectively). Moreover, these unfavorable associations were more obvious in women compared to men, with a borderline significant interaction effect for BMI (P=0.051). Our study showed that higher blood concentration of zinc, an essential trace element, was associated with unfavorable changes of the component metabolic risk factors of MetS, especially with BMI and LDL-c. Notably, these associations seemed to be more pronounced in women rather than in men. Further studies are warranted to elucidate the role of zinc status in the underlying mechanisms of MetS.

3.
World Neurosurg ; 180: e624-e630, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806522

RESUMO

OBJECTIVE: The aim of this study was to retrospectively analyze the clinical data of 16 patients with cavernous sinus cholesteatomas, explore the surgical outcomes, and summarize the surgical experience. METHODS: Patients with cavernous sinus cholesteatomas underwent surgery between June 2016 and June 2022 at the Department of Neurosurgery at the First Affiliated Hospital of Soochow University. Clinical data were obtained from all patients for analysis. RESULTS: Common preoperative symptoms included headache, dizziness, diplopia, ptosis, and facial numbness. There were 7 patients with 2 or more symptoms. There were 13 patients with total resection and 3 patients with subtotal resection. There were 5 patients with improved postoperative symptoms, 10 patients with no significant change, and 1 patient with worse symptoms. New postoperative cranial nerve defects occurred in 4 patients. During the follow-up, all patients had favorable prognosis without progression. CONCLUSIONS: Using "double-scope" technique, the subtemporal approach, a surgical strategy for cavernous sinus cholesteatomas, was sufficient to completely resect the tumors.


Assuntos
Seio Cavernoso , Humanos , Seio Cavernoso/diagnóstico por imagem , Seio Cavernoso/cirurgia , Seio Cavernoso/patologia , Estudos Retrospectivos , Endoscopia , Procedimentos Neurocirúrgicos/métodos , Nervos Cranianos , Resultado do Tratamento
4.
J Orthop Surg Res ; 18(1): 624, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37626361

RESUMO

OBJECTIVE: Surgical management of elderly patients with spinal tuberculosis and severe osteoporosis is challenging. Cement-augmented pedicle screws (CAPS) have been specifically designed for elderly patients with osteoporotic spines. Herein, we investigated the feasibility of CAPS applied in elderly patients with spinal tuberculosis and severe osteoporosis. METHODS: We retrospectively analyzed data of patients with spinal tuberculosis and severe osteoporosis between January 2017 and January 2021. Surgical data, including surgical duration and intraoperative blood loss, were recorded. Radiological parameters, such as correction of regional kyphotic angle and screw loosening, were also evaluated. Additionally, visual analog scores (VAS) and Oswestry disability index (ODI) were used to evaluate back pain and functional recovery, respectively. Erythrocyte sedimentation (ESR) and C-reactive protein (CRP) concentrations were detected to assess tuberculosis activity. The presence of complications and fusion rate was also assessed. RESULTS: A total of 15 patients were included in this study. The surgical duration was 263.0 ± 56.2 min, with an average blood loss of 378.7 ± 237.0 ml. The correction of regional kyphotic angle was 12.4° ± 15.0°, and it was well maintained until the final follow-up. The mean VAS decreased from 6.0 ± 1.2 points to 0.5 ± 0.6 points, and ODI reduced from 37.8% ± 7.6% to 8.3% ± 2.8% (P < 0.01). At the final follow-up, ESR and CRP levels were within normal range. Bony fusion occurred in all patients, with an average fusion duration of 8.8 ± 1.5 months. No cases of pedicle screw pullout, screw loosening, or pseudoarthrosis occurred. Tuberculosis recurrence and dissemination were not observed during the follow-ups. CONCLUSIONS: CAPS fixation is an effective and safe technique to achieve solid fixation and favorable clinical outcomes in elderly patients with spinal tuberculosis and severe osteoporosis.


Assuntos
Cifose , Osteoporose , Parafusos Pediculares , Tuberculose da Coluna Vertebral , Idoso , Humanos , Tuberculose da Coluna Vertebral/diagnóstico por imagem , Tuberculose da Coluna Vertebral/cirurgia , Estudos Retrospectivos , Osteoporose/complicações , Osteoporose/cirurgia , Perda Sanguínea Cirúrgica , Cimentos Ósseos , Cifose/diagnóstico por imagem , Cifose/cirurgia
6.
Chemosphere ; 335: 139080, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37263510

RESUMO

Important functions of constructed wetland related to biogeochemical processes are mediated by soil microbes and low-temperature damage is the main limiting factor for microbes in winter. However, the response thresholds for active microbial community and enzyme activities to continuous decreases in temperature remain unclear. In this study, total 90 soil samples were collected every week over a 6-week period to track the dynamics of four enzymes involved in cycles of C, N, P and active bacterial community as field soil temperature decreased continuously from 6.62 °C to 0.55 °C. Enzyme activity changed suddenly when the temperature decreased to 4.83 °C, the nitrite reductase activity reduced by 36.2%, while alkaline phosphatase activity is increased by 396%. The cellulase and urease were only marginally influenced by cold stress. Decreased nitrite reductase activities corresponded with loss of nir-type denitrifiers important for nitrite reduction. For cold stress, N-related bacteria were sensitive species. Whereas increased alkaline phosphatase activity may be due to the fact that P-related bacteria were opportunistic species. Key functional taxa connected with degradation of cellulose promoted species coexistence and microbial network stability. The lower and upper temperature thresholds for community change were 4.85 °C and 6.30 °C, respectively. Collectively, these results revealed that microbial taxa involved in C, N and P cycling respond differently to continuous decreases in temperature and higher than 4.85 °C is an ideal environment to prevent loss of microbial diversity and functions in winter, providing a scientific reference for the targeted isolation and cultivation of key microbial taxa in rhizosphere soil and adjusting temperature range to improve the purification capacity of wetlands during low temperature periods.


Assuntos
Microbiota , Áreas Alagadas , Temperatura , Fosfatase Alcalina/metabolismo , Bactérias/metabolismo , Solo/química , Nitrito Redutases/metabolismo , Microbiologia do Solo
7.
J Med Virol ; 95(5): e28782, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37212323

RESUMO

Mainland China included Japanese encephalitis (JE) vaccine in the national immunization program in 2008 to control the JE epidemic. However, Gansu province in Western China experienced the largest JE outbreak since 1958 in 2018. We conducted a retrospective epidemiological study to explore the causes of this outbreak. We found that adults aged ≥20 years (especially those in rural areas) were the main JE cases in Gansu Province, with a significant increase in the JE incidence in older adults aged ≥60 years in 2017 and 2018. In addition, JE outbreaks in Gansu Province were mainly located in the southeastern region, while the temperature and precipitation in Gansu Province were gradually increasing in recent years, which made the JE epidemic areas in Gansu Province gradually spread to the western of Gansu Province. We also found that adults aged ≥20 years in Gansu Province had lower JE antibody positivity than children and infants, and the antibody positivity rate decreased with age. In the summer of 2017 and 2018, the density of mosquitoes (mainly the Culex tritaeniorhynchus) in Gansu Province was significantly higher than in other years, and the genotype of JEV was mainly Genotype-G1. Therefore, in the future JE control in Gansu Province, we need to strengthen JE vaccination for adults. Moreover, strengthening mosquito surveillance can provide early warning of JE outbreaks and the spread of epidemic areas in Gansu Province. At the same time, strengthening JE antibody surveillance is also necessary for JE control.


Assuntos
Culicidae , Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Vacinas contra Encefalite Japonesa , Criança , Lactente , Animais , Humanos , Idoso , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/prevenção & controle , Vírus da Encefalite Japonesa (Espécie)/genética , Estudos Retrospectivos , Vacinação , Surtos de Doenças , China/epidemiologia
8.
PLoS One ; 18(3): e0282430, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36862707

RESUMO

The in-plane seismic behavior of unreinforced masonry (URM) structures is closely related to the aspect ratio of the wall and vertical load. The purpose of this study was to investigate the difference between the failure mode of the model and the horizontal load using the finite element model (FEM) under the action of aspect ratio (0.50 to 2.00) and vertical load (0.2 MPa to 0.70 MPa). The overall macro model was established using the Abaqus software, and the corresponding simulation was performed. The simulation results indicate that: i) the shear failure and flexural failure were the main failure modes of masonry walls; ii) shear failure could be viewed as the main failure mode of the model when the aspect ratio was less than 1.00; however, the flexural failure was considered to be the main failure mode of the model once the aspect ratio was greater than 1.00; iii) when a vertical load of 0.20 MPa was applied to the model, only flexural failure was observed, regardless of whether the aspect ratio of the model increased or decreased; the flexural shear mixed failure was captured within the range of 0.30 MPa- 0.50 MPa; the shear failure was the main failure mode within the range of 0.60 MPa- 0.70 MPa; and iv) the wall with an aspect ratio less than 1.00 could bear a higher horizontal load, and the increase in vertical load can significantly improve the horizontal load of the wall. In contrast, once the aspect ratio of the wall reaches or exceeds 1.00, the increase in the vertical load has little effect on the increase in the horizontal load of the wall.


Assuntos
Software , Simulação por Computador
9.
Am J Trop Med Hyg ; 108(4): 639-640, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36746664
10.
Exp Cell Res ; 421(1): 113375, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36208716

RESUMO

MRG domain binding protein (MRGBP) has been proposed to participate in the development of multiple tumors. However, the role of MRGBP in colorectal cancer (CRC) still remains largely unknown. Here, we found that MRGBP expression is significantly elevated in CRC, and that higher MRGBP expression correlates with poorer survival in CRC patients. Experiments in vivo and in vitro indicated that MRGBP promotes CRC cells proliferation, migration, invasion, epithelial-mesenchymal transition (EMT) and xenograft tumor growth. Mechanically, for one thing, we discovered that MRGBP suppresses DKK1 expression, thus further activating the Wnt/ß-catenin pathway in CRC cells. For another, MRGBP also enhances acetylation of NF-kB/p65 pathway. Treatment with Wnt/ß-catenin and NF-kB pathways inhibitors further confirmed the mediation of these two pathways in MRGBP-promoted CRC cell processes. In conclusion, these findings together suggest that MRGBP promotes CRC progression via DKK1/Wnt/ß-catenin and NF-kB/p65 pathways mediated EMT, identifying MRGBP as a promising prognostic and therapeutic target for CRC.


Assuntos
Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Histona Acetiltransferases , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metástase Neoplásica , NF-kappa B/genética , NF-kappa B/metabolismo , Via de Sinalização Wnt/genética , Proteínas Nucleares/metabolismo , Histona Acetiltransferases/metabolismo
11.
Nat Methods ; 19(10): 1243-1249, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36109677

RESUMO

Joint profiling of chromatin accessibility and gene expression from the same single cell provides critical information about cell types in a tissue and cell states during a dynamic process. Here, we develop in situ sequencing hetero RNA-DNA-hybrid after assay for transposase-accessible chromatin-sequencing (ISSAAC-seq), a highly sensitive and flexible single-cell multi-omics method to interrogate chromatin accessibility and gene expression from the same single nucleus. We demonstrated that ISSAAC-seq is sensitive and provides high quality data with orders of magnitude more features than existing methods. Using the joint profiles from over 10,000 nuclei from the mouse cerebral cortex, we uncovered major and rare cell types and cell-type specific regulatory elements and identified heterogeneity at the chromatin level within established cell types defined by gene expression. Finally, we revealed distinct dynamics and relationships of gene expression and chromatin accessibility during an oligodendrocyte maturation trajectory.


Assuntos
Cromatina , Sequenciamento de Nucleotídeos em Larga Escala , Animais , Cromatina/genética , DNA , Expressão Gênica , Camundongos , RNA , Transposases/genética , Transposases/metabolismo
12.
Front Public Health ; 10: 895474, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35991052

RESUMO

Wearable physical activity trackers are getting popular for the self-management of weight despite limited evidence of their efficacy. Studies have proven that on-site supervised exercise is superior to unsupervised exercise for many health problems, there is no evidence comparing the effectiveness of remote supervision exercise with self-directed exercise based on mHealth. This study aims to compare the effects of mHealth-based supervised exercise to mHealth-based self-directed exercise on weight control in the overweight and obese population. A nonrandomized controlled clinical study was conducted. Overweight or obese volunteers were given personalized exercise prescriptions based on their HRR (Heart Rate Reserve), all patients were equipped with wearable heartbeat trackers to follow their exercise performance and additional remote supervisions were added to the intervention group. Exercise performances, weight losses, and health examinations were compared between 2 groups after 12 weeks of follow-up. Analysis of covariance (ANCOVA) was used to determine any differences between study groups after intervention. Two groups had the same rate of attrition in 12 weeks of follow-up, but the exercising day, the effective exercising day and the rate of effective exercising day in the supervised group were higher than those in the control group. Weight loss was -2.7 ± 2.8 kg in the intervention group and -2.0 ± 2.9 kg in the control group (P = 0.23). Compared with the control group, participants in the intervention group improved their liver function, kidney function, fasting blood sugar, total cholesterol, and triglyceride. mHealth-based supervised exercise is more effective in health factors improvement than mHealth-based self-directed exercise among overweight and obesity participants.


Assuntos
Sobrepeso , Telemedicina , Exercício Físico/fisiologia , Humanos , Obesidade/terapia , Sobrepeso/terapia , Redução de Peso/fisiologia
13.
Front Oncol ; 12: 828361, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186760

RESUMO

OBJECTIVE: Pineal region meningiomas are deeply located and adjacent to critical neurovascular structures, making them one of the most challenging areas to access. The authors presented a combined microscopic and endoscopic surgery and investigated its value in resecting pineal region meningiomas. METHODS: Twelve patients with pineal region meningiomas from February 2017 to December 2020 were retrospectively reviewed. All patients underwent combined microscopic and endoscopic surgery using the occipital-parietal transtentorial approach. Perioperative clinical, surgical, and radiographic data were collected. RESULTS: The endoscope provided a wider view and increased visualization of residual tumors. All tumors were completely resected, and none of the patients died. Total resection was believed to have been achieved in four patients, but the residual tumor was detected after endoscopic exploration and was completely resected with an endoscope. Only one patient had transient visual field deficits. No recurrence was observed during follow-up. CONCLUSIONS: Combined microscopic-endoscopic surgery for pineal region meningiomas eliminates microscopic blind spots, thus compensating for the shortcomings of the traditional occipital transtentorial approach. It is a promising technique for minimally invasive maximal resection of pineal region meningiomas.

14.
Int J Occup Med Environ Health ; 35(2): 199-208, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-34658367

RESUMO

OBJECTIVES: The objective of this study was to explore the relationship between seat armrest height and human neck comfort when using a smartphone while sitting on a passenger seat during the flight. MATERIAL AND METHODS: The authors used a wireless angle-measuring instrument and subjective comfort scale to evaluate the changes of head flexion angle and neck comfort level of 24 young smartphone users in an aircraft simulated cabin. RESULTS: The study results indicated that using a smartphone while sitting on a passenger seat during the flight would pose a larger discomfort to the neck, and the discomfort would be higher for gaming than reading tasks. Seat armrest height is related to the comfort level of the neck when using a smartphone, increasing the height of the armrest can effectively alleviate discomfort in this state. CONCLUSIONS: Considering the prevalence of passengers using smartphones in aircraft, a seat armrest that can be properly adjusted in height, which can effectively reduce the risk of passenger head flexion angle and neck discomfort. Int J Occup Med Environ Health. 2022;35(2):199-208.


Assuntos
Postura , Smartphone , Aeronaves , Desenho de Equipamento , Ergonomia , Humanos , Pescoço
16.
Front Plant Sci ; 12: 658883, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262575

RESUMO

Plant functional composition, defined by both community-weighted mean (CWM) traits and functional diversity, can provide insights into plant ecological strategies and community assembly. However, our understanding of plant functional composition during succession is largely based on aboveground traits. Here we investigated community-level traits and functional diversity for six pairs of analogous leaf and fine root traits of understory plants in a temperate forest swamp during succession with a decrease in soil pH and nutrient availability. CWMs of traits related to resource acquisition (including specific leaf area, specific root length, leaf N, leaf P, root N, and root P) decreased with succession, whereas those related to resource conservation (leaf dry matter content, root dry matter content, leaf tissue density, leaf C, and root C) increased along the forest swamp successional gradient. Multi-trait functional dispersion (FDis) of both leaf and fine root traits tended to decrease along the successional gradient, but functional richness and evenness were highest at the middle successional stage. Moreover, FDis of individual plant traits except N showed the same pattern as multi-trait FDis. Soil pH and nutrient availability were the main drivers of successional changes in both CWM traits and FDis. The changes of community-level traits along succession indicated a shift from acquisitive to conservative strategy of understory plants during forest swamp succession. Similar trends in leaf and fine root functional diversity along succession may indicate above- and belowground functional diversity are coordinated during the processes of plant community assembly. These findings of linkages between above- and belowground plant functional composition have important implications for plant community dynamics and assembly rules.

17.
J Colloid Interface Sci ; 589: 275-285, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33472147

RESUMO

The diffusion of stubborn oils and organic pigments has become a severe environmental pollution problem. Promisingly, the combination of superhydrophobicity and photocatalysis is expected to provide an efficient, economical and simple solution. In this paper, a kind of superhydrophobic and super-lipophilicity polyurethane (PU)-based sponge was reported by a strategy of undergoing ferric tetroxide loading (Fe3O4@PU), polydopamine fixation (PDA-Fe3O4@PU), octadecylamine grafting (ODA-Fe3O4@PU) and molybdenum disulfide loading (MoS2-ODA-Fe3O4@PU) successively. The results show that the MoS2-ODA-Fe3O4@PU sponge exhibits outstanding superhydrophobicity (with maximum water contact angle of 161.64°), excellent oil absorption capacity (60-109 wt/wt), robust stability in extreme environments and great oil/water separation ability. In addition, the MoS2-loaded sponge demonstrates desirable outcomes in decomposing methyl orange and methylene blue under light source, and a dual-functional purification system with a heterogeneous polyurethane-based sponge (the upper part is MoS2-ODA-Fe3O4@PU and the bottom part is MoS2@PU) endowed with superhydrophobicity and photocatalysis can purify water by separating oils and decomposing methylene blue simultaneously.

18.
Comput Intell Neurosci ; 2021: 6992648, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35915600

RESUMO

With interdisciplinarity being an important characteristic of contemporary product design, the evaluation of design alternatives also involves multiple disciplines, and the evaluator group usually consists of evaluators from different fields and with obvious heterogeneous characteristics. To effectively satisfy the heterogeneous needs of evaluators and improve the credibility of evaluation results, the paper introduces a consensus-reaching approach that incorporates multiple preferences to the evaluation of product design alternatives. First, in order to obtain individual preference information, each evaluator is asked to evaluate all the design alternatives using a preference structure that he/she is familiar with. Second, we use a transfer function to uniform the evaluation information obtained from various preference structures into a complementary judgment matrix. Then, we use the Hybrid Weighted Averaging (HWA) operator weight determination model to aggregate the preference information and obtain the group preference information. Then, we measure the consensus degree between individual evaluators and the group using a consensus measurement method. After that, we use the feedback mechanism to instruct individual evaluators to modify their preferences until a consensus is achieved. We explain the application steps and the feasibility of this approach through the evaluation of the design alternatives of multichannel fluorescence immunochromatography analyzers (MFIAs).


Assuntos
Julgamento , Consenso , Feminino , Humanos
19.
Sci China Life Sci ; 64(4): 593-605, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32975721

RESUMO

Patterns of plant trait variation across spatial scales are important for understanding ecosystem functioning and services. However, habitat-related drivers of these patterns are poorly understood. In a conceptual model, we ask whether and how the patterns of within- and among-site plant trait variation are driven by habitat type (terrestrial vs. wetland) across large climatic gradients. We tested these through spatial-hierarchical-sampling of leaves in herbaceous-dominated terrestrial and wetland communities within each of 26 sites across China. For all 13 plant traits, within-site variation was larger than among-site variation in both terrestrial and wetland habitats. Within-site variation was similar in most leaf traits related to carbon and nutrient economics but larger in specific leaf area and size-related traits (plant height, leaf area and thickness) in wetland compared to terrestrial habitats. Among-site variation was larger in terrestrial than wetland habitats for 10 leaf traits but smaller for plant height, leaf area and leaf nitrogen. Our results indicate the important role of local ecological processes in driving plant trait variation among coexisting species and the dependence of functional variation across habitats on traits considered. These findings will help to understand and predict the effects of climatic or land-use changes on ecosystem functioning and services.


Assuntos
Clima , Ecossistema , Variação Genética , Plantas/genética , Locos de Características Quantitativas/genética , Áreas Alagadas , Biodiversidade , Carbono/metabolismo , China , Clorofila/metabolismo , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Plantas/anatomia & histologia , Plantas/metabolismo , Solo/química
20.
Ying Yong Sheng Tai Xue Bao ; 31(10): 3385-3394, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33314828

RESUMO

Investigating ecological stoichiometry of leaves and fine roots of forest swamps in the Greater Hinggan Mountains will improve our understanding of plant nutrient use and material cycling in ecosystems at high latitudes with high sensitivity to climate change. In this study, we collected leaf and fine root samples from 19 dominant and subordinate vascular plant species and measured their C, N and P concentrations in three typical forest swamps (Larix gmelinii-Carex schmidtii, L. gmelinii-Vaccinium uliginosum-moss and L. gmelinii-Ledum palustre-Sphagnum) of the Greater Hinggan Mountains, China. We compared C:N:P stoichiometry in leaves and fine roots among different forest swamp types, plant growth forms, and mycorrhizal types. Standardized major axis regression was performed to examine the relationships between leaf and fine root stoichiometry. The results showed that interspecific variation accounted for the largest proportion of total variation in C:N:P stoichiometry of leaves (42.5%-84.6%). N:P had the highest, C:N had the intermediate, and C:P had the lowest interspecific variation in both leaves and fine roots. L. gmelinii-C. schmidtii forest swamps, which had higher soil nutrient and water availability, had lower C:N and C:P in leaves and fine roots. N:P of all three forest swamps were lower than 10, indicating N limitation in this ecosystem. Herbaceous plants had significantly lower leaf C:P, fine root C:N, and fine root C:P than woody species. Both ectomycorrhizal and ericoid mycorrhizal plants had higher leaf and fine root C:N and C:P than arbuscular mycorrhizal and non-mycorrhizal species, while the C:P of ericoid mycorrhizal plants was significantly higher than that of ectomycorrhizal species. Forest swamp type, plant growth form, and mycorrhizal type all had greater influences on leaf and fine root C:N and C:P rather than N:P. Leaf and fine root C:N, C:P, and N:P were positively correlated, indicating strong coordination between plant above- and below-ground C:N:P stoichiometry.


Assuntos
Ecossistema , Áreas Alagadas , China , Florestas , Nitrogênio , Folhas de Planta , Raízes de Plantas , Solo
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