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Superhydrophobic materials are attractive for industrial development but plagued by poor mechanical stability. Herein, a superdurable full-life superhydrophobic composite block is designed and fabricated by embedding near-zero contractive superhydrophobic silica aerogel into a rigid iron-nickel foam structured similarly to a regular dodecahedron. The synergistic protection afforded by these materials ensures superrobust mechanical stability for the composite block, which features a high compressive strength of up to ≈7.4 MPa, and ultralow Taber abrasion of down to ≈0.567 mm after withstanding 50 000 cycles, and highly efficient water harvesting capability of up to ≈3114.3 mg min-1 cm-2 at a supercooling degree of 40 K. This robust material system provides a novel strategy to design superhydrophobic materials capable of withstanding extreme conditions, including high temperature, humidity, pressure, and abrasion.
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Soil organic carbon (SOC) is a crucial medium of the global carbon cycle and is profoundly affected by multiple factors, such as climate and management practices. However, interactions between different SOC fractions and land-use change have remained largely unexplored in karst ecosystems with widespread rock outcrops. Owing to the inherent heterogeneity and divergent response of SOC to land-use change, soil samples with close depth were collected from four typical land-use types (cropland, grassland, shrubland, and forestland) in the karst rocky desertification area of China. The aim of this study was to explore the responses of SOC dynamics to land-use types and underlying mechanism. The results showed that land-use type significantly affected SOC contents and its fractions. Compared with cropland, the other three land uses increased the total organic carbon (TOC), microbial biomass carbon (MBC), and non-labile organic carbon (NLOC) contents by 6.11-129.44%, 32.58-173.73%, and 90.98-347.00%, respectively; this demonstrated that a decrease in both labile and recalcitrant carbon resulted in SOC depletion under agricultural land use. Readily oxidized organic carbon (ROC) ranged from 42 to 69%, accounting for almost half of the TOC in the 0-40-cm soil layer. Cropland soil showed significantly higher ROC:TOC ratios than other land-use types. These results indicated that long-term vegetation restoration decreased SOC activity and improved SOC stability. Greater levels of soil exchangeable calcium (ECa) and clay contents were likely responsible for higher stabilization and then accumulation of SOC after vegetation restoration. The carbon pool index (CPI) rather than the carbon pool management index (CPMI) exhibited consistent variation trend with soil TOC contents among land-use types. Thus, further study is needed to validate the CPMI in evaluating land use effects on soil quality in karst ecosystems. Our findings suggest that land-use patterns characterized by grass or forest could be an effective approach for SOC-sequestration potential and ensure the sustainable use of soil resources in the karst area.
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Cálcio , Carbono , Argila , Solo , China , Solo/química , Carbono/análise , Cálcio/análise , Argila/química , Ecossistema , Agricultura , Ciclo do CarbonoRESUMO
This study aimed to investigate the impact of caloric restriction (CR) on cognitive function in aged C57BL/6 mice after surgery, as well as the underlying mechanisms. Forty 14-month-old male C57BL/6 mice were randomly assigned to the ad libitum (AL, n = 20) group and the CR (n = 20) group. After feeding for 12 weeks, they were subdivided into four groups: AL control (ALC, n = 10), AL with surgery (ALS, n = 10), CR control (CRC, n = 10), and CR with surgery (CRS, n = 10). The Morris Water Maze (MWM) test was used to assess learning and memory capacity. By using western blot and immunofluorescence, the expression of Sirt1, MeCP2, and BDNF in the hippocampus and hippocampal CA1 region was quantified. According to the behavioral test, the CRC and CRS groups had significantly better learning and memory abilities than the ALC and ALS groups, respectively. Sirt1, MeCP2, and BDNF expression in the hippocampus and CA1 region in the hippocampus of the ALC and CRC groups of mice were correlated with cognitive improvement. In conclusion, CR could enhance the postoperative cognitive function in aged mice, most likely by increasing the expression of Sirt1, MeCP2, and BDNF in the CA1 region of the hippocampus.
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As a highly infectious pathogen, Bombyx mori nuclear polyhedrosis virus (BmNPV) has a high lethality rate in silkworm. Our previous study have confirmed that Hsp90 plays a positive role in BmNPV proliferation and Hsp90 inhibitor, geldanamycin (GA) can decrease the replication of BmNPV in vitro. However, its molecular mechanism is not fully understood. In the present study, first, we found that GA could inhibit the proliferation of BmNPV in a dose-dependent manner and delay the pathogenesis of BmNPV in vivo possibly by altering the transcript level of genes associated with cell apoptosis and immune pathways. Furthermore, by immunoprecipitation (IP) and mass spectrometry analysis, we identified a series of proteins potentially interacting with Hsp90 including two BmNPV encoded proteins. Subsequently, by Co-IP we confirmed the interaction between BmActin-4 and BmHsp90. Knocking down Bmhsp90 by small interfering RNA inhibited the protein expression level of BmActin-4. Over-expression of Bmactin-4 promoted the replication of BmNPV whereas knockdown of Bmactin-4 suppressed BmNPV replication. In addition, decrease of the transcript level of Bmhsp90 in Bmactin-4 knocking down BmN cells was also detected. Taken together, BmHsp90 can interact with BmActin-4 and promote its expression, thereby promoting BmNPV proliferation. Our findings may enrich the molecular mechanism of Hsp90 for promoting virus proliferation and provide new clues to elucidate the interact mechanism between silkworm and virus.
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Bombyx , Nucleopoliedrovírus , Animais , Actinas/metabolismo , Nucleopoliedrovírus/genética , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proliferação de CélulasRESUMO
This study aims to analyze the serum neutralization capacity against Delta and Omicron variants in three clusters of individuals, including those who had recovered from COVID-19 and those who had received two and three doses of inactivated vaccine. Pseudovirus neutralization tests were performed on serum samples. The neutralizing titers between different groups were compared using the Wilcoxon's signed-rank test. Among the two-dose vaccinees, the neutralization titers of the Omicron variant were reduced by approximately 3.1-fold compared to the wild-type virus (p < 0.05). Meanwhile, among the three-dose vaccinees, the neutralization titers for Delta and Omicron variants were 3.5-fold (p < 0.05) and 5.0-fold (p < 0.05) lower, respectively, as compared to the wild-type virus. In addition, among the recovering patients, the neutralization titers for Delta and Omicron variants were 3.9-fold (p < 0.05) and 29.1-fold (p < 0.05) lower, respectively, as compared to the wild-type virus. Overall, only 12.0% (11/92) of participants showed neutralizing titers against Omicron above the detection limit. The ability to neutralize wild-type pseudovirus was significantly boosted in three-dose vaccinees as compared to two-dose vaccinees. Sera from recovered patients showed greater neutralizing titers for the wild-type and Delta pseudoviruses than the two- and three-dose inactivated vaccine groups. The present study revealed a loss of neutralizing activity against the Omicron variant in almost all samples. Moreover, the immunization effect obtained through natural infection is more robust than that from the active immunization method of vaccination.
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Background: Triglyceride-glucose (TyG) index is a simple marker of insulin resistance. However, insufficient data is available on whether the TyG index is associated with worsening renal function (WRF) in the elderly. Therefore, this study was designed to explore the association between the TyG index and WRF based on a community elderly cohort. Methods: In this study, 7,822 elderly (aged ≥ 65 years) adults from southern China were enrolled and divided into four groups according to the TyG index quartiles. The primary endpoint was incident chronic kidney disease (CKD), defined as incident estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. Additional endpoints included a decline in eGFR of 30% and 40% during the follow-up period. Results: During the median 2.04 year follow-up period, 1,541 (19.7%) participants developed CKD. After adjusting for confounding factors, multivariable Cox regression models revealed significant associations between TyG index and incident CKD (HR per SD increase, 1.21; 95% CI: 1.14-1.29), a decline in eGFR of 30% (HR per SD increase, 1.38; 95% CI: 1.26-1.50), and decline in eGFR of 40% (HR per SD increase, 1.42; 95% CI: 1.24-1.63). Furthermore, compared with those in Q1, participants in Q4 demonstrated a higher risk of developing CKD (HR, 1.59; 95% CI: 1.35-1.88). These positive associations remained consistent across different subgroup populations. Conclusion: Our study suggests a positive and independent association between the TyG index and WRF in the elderly.
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Bombyx mori nuclear polyhedrosis virus (BmNPV) is one of several viruses that cause great harm to the sericulture industry, and its pathogenic mechanism is still being explored. Geldanamycin (GA), a kind of HSP90 inhibitor, has been verified to suppress BmNPV proliferation. However, the molecular mechanism by which GA inhibits BmNPV is unclear. MicroRNAs (miRNAs) have been shown to play a key role in regulating virus proliferation and host-pathogen interactions. In this study, BmN cells infected with BmNPV were treated by GA and DMSO for 72 h, respectively, then transcriptome analysis of miRNA was performed from the GA group and the control group. As a result, a total of 29 miRNAs were differentially expressed (DE), with 13 upregulated and 16 downregulated. Using bioinformatics analysis, it was found that the target genes of DEmiRNAs were involved in ubiquitin-mediated proteolysis, phagosome, proteasome, endocytosis pathways, and so on. Six DEmiRNAs were verified by quantitative reverse-transcription polymerase chain reaction. DElong noncoding RNA (DElncRNA)-DEmiRNA-messenger RNA (mRNA) regulatory networks involved in apoptosis and immune pathways were constructed in GA-treated BmN cells, which included 12 DEmiRNA, 132 DElncRNA, and 69 mRNAs. This regulatory network enriched the functional role of miRNA in the BmNPV-silkworm interactions and improved our understanding of the molecular mechanism of HSP90 inhibitors on BmNPV proliferation.
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Bombyx , MicroRNAs , Nucleopoliedrovírus , Animais , Benzoquinonas , Bombyx/metabolismo , Lactamas Macrocíclicas , MicroRNAs/genética , MicroRNAs/metabolismo , Nucleopoliedrovírus/fisiologia , RNA Mensageiro/metabolismo , TranscriptomaRESUMO
BACKGROUND: China is one of the countries sharing the major burden of tuberculosis (TB) in the world. Health care workers (HCWs) are subject to a high risk of occupational latent tuberculosis infection (LTBI)-an asymptomatic state of TB disease. However, the heterogenic composition of healthcare professionals in terms of nature of their work leads to the inconsistency in predicting the prevalence of LTBI amongst them. Furthermore, the global statistics do not account for the analysis conducted within the Chinese population. Our study reflects a systemic and epidemiological meta-analysis to investigate the risk of contracting LTBI by the HCWs of China. METHODS: A systematic review of the literature was performed to identify studies reporting LTBI prevalence or incidence among HCWs and a control groups in China. Risk of infection, as well as subgroup analysis was calculated by pooled effect estimates. Review Manager 5.0 was used to perform the meta-analyses. RESULTS: Twenty studies containing 9,654 HCWs met the inclusion criteria. The average prevalence of LTBI among HCWs was 51.5%, ranging from 27.9-88.8%. HCWs had a higher risk of prevalence of LTBI than the control groups [odds ratio (OR), 1.78, 95% confidence interval (CI), 1.46-2.16]. In the subgroup analysis, the prevalence of LTBI in HCWs with respect to the control groups was observed to be highest in Eastern China (OR, 2.05; 95% CI, 1.35-3.11). Furthermore, the pooled OR for LTBI was 1.90 and 1.65 separately from the results of the tuberculin skin test (TST) and the interferon-gamma release assay. Lastly, upon comparing the HCWs with the control groups from the community and the nosocomial source, it was observed that the pooled OR favored for the prevalence of LTBI, which was primarily community-sourced (3.12 and 1.54). HCWs had an increased risk of prevalence of LTBI than the control groups, both in general hospitals and TB specific hospitals (pooled OR 2.4 and 1.57). CONCLUSIONS: Risk of LTBI infection among HCWs is relatively high in China, especially in the eastern region, predisposed by the cumulative exposure to Mycobacterium tuberculosis from the community and the general hospitals. Overall, our data reflects an alarming risk posed to our HCWs, and calls for immediate reforms at the policy levels, so as to implement effective screening and treatment of affected HCWs in China.
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Bombyx mori nucleopolyhedrosis virus (BmNPV) is one of the greatest threats to sustainable development of the sericulture industry. Circular RNA (circRNA), a type of non-coding RNA, has been shown to play important roles in gene expression regulation, immune response, and diseases. The fat body is a tissue with both metabolic and immune functions. To explore the potential immune function of circRNAs, we analyzed differentially expressed (DE)circRNAs, microRNAs(miRNAs), and mRNAs in the B. mori fat body in response to BmNPV infection using high-throughput RNA sequencing. A total of 77 DEcircRNAs, 32 DEmiRNAs, and 730 DEmRNAs that are associated with BmNPV infection were identified. We constructed a DEcircRNA/DEmiRNA/DEmRNA and DEcircRNA/DEmiRNA/BmNPV gene regulatory network and validated the differential expression of circ_0001432 and its corresponding miRNA (miR-2774c and miR-3406-5p) and mRNA (778467 and 101745232) in the network. Tissue-specific expression of circ_0001432 and its expression at different time points were also examined. KEGG pathway analysis of DEmRNAs, target genes of DEmiRNAs, and host genes of DEcircRNAs in the network showed that these genes were enriched in several metabolic pathways and signaling pathways, which could play important roles in insect immune responses. Our results suggest that circRNA could be involved in immune responses of the B. mori fat body and help in understanding the molecular mechanisms underlying silkworm-pathogen interactions.
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Bombyx/genética , Bombyx/imunologia , Corpo Adiposo/imunologia , Redes Reguladoras de Genes/imunologia , Imunidade Inata/genética , Nucleopoliedrovírus/fisiologia , RNA Circular/genética , Animais , Bombyx/crescimento & desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Larva/genética , Larva/crescimento & desenvolvimento , Larva/imunologia , MicroRNAs/genética , MicroRNAs/imunologia , RNA Circular/imunologia , RNA Circular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/imunologiaRESUMO
The emphasis of this study lies in that we present a novel fluorescence scanning approach to evaluate the antioxidant capacity of Fritillaria ussuriensis polysaccharide-zinc (FUP-Zn) complex. FUP was extracted successfully, and the corresponding FUP-Zn complexes with different substitution degrees were obtained after modified chemically with ZnCl2. The physiochemical characteristics of the as-prepared samples were determined by ultraviolet-visible spectroscopy, infrared spectroscopy, X-ray powder diffraction, scanning electron microscope, energy dispersive spectrum, thermo gravimetric-differential thermal analyses and etc., and these characterization results confirmed the successful synthesis of FUP-Zn complexes with good stability. The scavenging ability investigation of FUP-Zn complexes towards hydroxyl radicals and superoxide anion radicals carried out by us has revealed that the integration of FUP and Zn greatly enhanced the antioxidant activity due to the synergistic effect and larger pore size of FUP-Zn complexes, and the antioxidant activity of FUP-Zn complex with different substitution degrees is heavily dependent on the amount of Zn. This study indeed provides vital theoretical basis for the promising antioxidant and zinc supplement evaluation from more novel polysaccharide-zinc complexes with suited Zn amount.
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Antioxidantes/farmacologia , Fritillaria/química , Polissacarídeos/farmacologia , Zinco/farmacologia , Adsorção , Sequestradores de Radicais Livres/farmacologia , Peso Molecular , Monossacarídeos/análise , Nitrogênio/química , Polissacarídeos/ultraestrutura , Solubilidade , Espectrometria de Fluorescência , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxidos/química , Difração de Raios XRESUMO
Objectives: To investigate the effects of obesity caused by high-fat diet (HFD) on postoperative cognitive dysfunction (POCD) and expression of the Sirt1/PGC-1α/FNDC5/BDNF pathway in the hippocampus of older mice. Methods: Fifty-six 15-month-old male C57BL/6 mice were randomly divided into eight groups - ad libitum control (ALC), ad libitum surgery (ALS), ad libitum surgery with PBS (ALS + PBS), ad libitum surgery with resveratrol (ALS + Res), HFD control (HFC), HFD surgery (HFS), HFD surgery with PBS (HFS + PBS), HFD surgery with resveratrol (HFS + Res). Surgery group mice were exposed to isoflurane before tibial fracture internal fixation. Open field tests and fear conditioning were performed to test motor ability and memory. The levels of expression of Sirt1, PGC-1α, FNDC5, and BDNF were detected using western blot and immunofluorescence. Results: The results of the open field tests indicated there were no between-group differences in motor ability and anxiety. The results of the fear conditioning indicated that the memory of the HFC group and HFS group mice were significantly worse compared with the ALC group and ALS group mice, respectively. There were parallel decreases in expression of the Sirt1/PGC-1α/FNDC5/BDNF pathway in the hippocampi of the HFC and HFS group mice. Resveratrol treatment attenuated the memory loss by increasing hippocampal Sirt1 expression. Expression of the PGC-1α/FNDC5/ BDNF pathway in the CA1 area of the hippocampus was upregulated after resveratrol treatment. Conclusion: An HFD exacerbates POCD in older mice. This change was related to HFD inhibition of expression of the Sirt1/PGC-1α/FNDC5/BDNF pathway in the hippocampus. Resveratrol pretreatment reversed the memory loss via upregulation of this pathway.
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Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/metabolismo , Dieta Hiperlipídica , Isoflurano/administração & dosagem , Obesidade/metabolismo , Complicações Pós-Operatórias/induzido quimicamente , Complicações Pós-Operatórias/metabolismo , Transdução de Sinais , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fibronectinas/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Sirtuína 1/metabolismo , Fatores de Transcrição/metabolismoRESUMO
In mountainous areas, rock fragments (RFs) are a common feature on the soil surface and in topsoil. Few studies, however, have investigated the spatial distribution of RFs and the relevant mechanisms underpinning their distribution on steep hillslopes, especially in karst regions. We have collected and measured the RF cover, size, and content at the soil surface and within the topsoil of secondary forest, man-made forest, and non-forest land hillslopes in a karst region in Yunnan Province, southwest China. The results revealed no significant relationships between slope position and mean total RF coverage, median diameter (D50), and mean total volumetric RF in topsoil within the three karst hillslopes covered by different types of vegetation. A limited effect of vegetation on the spatial distribution of RFs on the hillslopes was identified. However, the variation in RFs in the topsoil between the top and bottom slopes was greater than that at the surface between the top and bottom slopes, implying that underground leakage was greater than surface runoff.
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Florestas , Geologia/métodos , Solo , China , Solo/químicaRESUMO
Postoperative cognitive dysfunction is common in the elderly. Endoplasmic reticulum stress (ER-stress) increases neuronal apoptosis after surgery, and chaperone molecules, such as heat shock proteins (HSPs), help reduce unfolded protein reactions, thereby promoting protein homeostasis. Mammal sirtuin1 (SIRT1)-mediated deacetylation of heat shock factor 1 (HSF1) upregulates HSF1 binding to the HSP70 promoter. Caloric restriction (CR) improves cognition in many neurodegenerative models. In this study, we evaluated whether CR improves impaired learning and memory after surgery by attenuating ER-stress in an SIRT1-dependent manner. Male 18-month-old C57BL/6J mice receiving a 12-week CR or an ad libitum (AL) diet pre-intervention were challenged with tibial open fracture surgery and anesthesia or no treatment. We found a significant protective effect of CR on memory in contextual fear conditioning test after surgery compared with the AL group. CR alleviated ER-stress and neuronal apoptosis in the hippocampus induced by surgery. CR increased HSP70 expression through the HSF1/HSP pathway in a SIRT1-mediated manner, and inhibition of SIRT1 in the hippocampus by lentivirus injection partially reduced the benefits of CR (increased HSP70, deacetylated HSF1, reduced ER-stress, and improved memory). Taken together, our results showed that CR alleviates memory impairment postoperatively via attenuation of ER-stress in the hippocampus in an SIRT1-dependent manner, and the SIRT1/HSF1/HSP70 pathway is involved in this process.
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Restrição Calórica , Disfunção Cognitiva/prevenção & controle , Proteínas de Choque Térmico HSP70/metabolismo , Fatores de Transcrição de Choque Térmico/fisiologia , Hipocampo/metabolismo , Neuroproteção , Sirtuína 1/fisiologia , Animais , Apoptose , Células Cultivadas , Estresse do Retículo Endoplasmático , Fatores de Transcrição de Choque Térmico/deficiência , Lentivirus , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sirtuína 1/deficiência , Fraturas da Tíbia/cirurgia , Regulação para CimaRESUMO
BACKGROUND: Silent Information Regulator 1 (Sirt1) and apoptosis play key roles in postoperative cognitive dysfunction (POCD). Consuming a high-fat diet (HFD), a prevalent type of diet in modern society, has been increasingly recognized as contributing to neurodegenerative diseases. Although Sirt1 and apoptosis are significant responders to HFD in the brain, little is known regarding the functional correlations between HFD and POCD. METHODS: Thirty-two aged C57BL/6 male mice were randomly divided into 2 groups: an ad libitum (AL) group (fed a regular diet) and high-fat diet (HF) group (fed a high-fat diet). After 8 weeks, the animals were divided into four sub-groups: an ad libitum control (ALC) group, ad libitum surgery (ALS) group, high-fat diet control (HFC) group, and high-fat diet surgery (HFS) group. The ALS and HFS groups were exposed to 3% sevoflurane in 33% oxygen for 3 h and were subsequently subjected to exploratory surgery to establish the POCD model. The ALC and HFC groups were treated with 33% oxygen for 3 h without surgery. After 48 h, the learning and memory abilities of mice in each group were tested using the Morris water maze (MWM). The expression levels of Sirt1, Bcl-2, Bax and caspase-3 cleaved were detected by western blot. RESULTS: The MWM and western blotting results showed that the learning and memory abilities were decreased in the HFC group compared with the ALC group. The learning and memory abilities and the expression of Sirt1 in the hippocampus in the HFS group were significantly decreased compared with the other groups. A significant decrease in Sirt1 expression was also observed in the HFC group compared with the ALS group. The level of Bcl-2 was lower in the HFS group than in the HFC and ALC groups. The expression levels of caspase-3 cleaved and Bax increased in the HFS group compared with the HFC group. Moreover, the expression of caspase-3 cleaved was higher in the HFC group than in the ALS group. CONCLUSION: HFD can aggravate POCD in aged C57BL/6 mice, an effect that may be related to the inhibition expression of Sirt1 and the promotion of neuronal apoptosis.
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Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Complicações Pós-Operatórias/fisiopatologia , Envelhecimento , Animais , Western Blotting , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Rock outcrop is an important habitat supporting plant communities in karst landscape. However, information on the restoration of higher biotic populations on outcrops is limited. Here, we investigated the diversity, biomass changes of higher vascular plants (VP) and humus soil (HS) on karst outcrops during a restoration process. We surveyed VP on rock outcrops and measured HS reserved by various rock microhabitats in a rock desertification ecosystem (RDE), an anthropogenic forest ecosystem (AFE), and a secondary forest ecosystem (SFE) in Shilin County, southwest China. HS metrics (e.g. quantity and nutrients content) and VP metrics (e.g. richness, diversity and biomass) were higher at AFE than at RDE, but lower than at SFE, suggesting that the restoration of soil subsystem vegetation increased HS properties and favored the succession of VP on rock outcrops. There was significantly positive correlation between VP metrics and HS amount, indicating that the succession of VP was strongly affected by availability and heterogeneity of HS in various rock microhabitats. Thus, floral succession of rock subsystem was slow owing to the limited resources on outcrops, although the vegetation was restored in soil subsystem.