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1.
World J Clin Cases ; 11(33): 8003-8012, 2023 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-38075574

RESUMO

BACKGROUND: The recovery time of hand wounds is long, which can easily result in chronic and refractory wounds, making the wounds unable to be properly repaired. The treatment cycle is long, the cost is high, and it is prone to recurrence and disability. Double layer artificial dermis combined with autologous skin transplantation has been used to repair hypertrophic scars, deep burn wounds, exposed bone and tendon wounds, and post tumor wounds. AIM: To investigate the therapeutic efficacy of autologous skin graft transplantation in conjunction with double-layer artificial dermis in treating finger skin wounds that are chronically refractory and soft tissue defects that expose bone and tendon. METHODS: Sixty-eight chronic refractory patients with finger skin and soft tissue defects accompanied by bone and tendon exposure who were admitted from July 2021 to June 2022 were included in this study. The observation group was treated with double layer artificial dermis combined with autologous skin graft transplantation (n = 49), while the control group was treated with pedicle skin flap transplantation (n = 17). The treatment status of the two groups of patients was compared, including the time between surgeries and hospital stay. The survival rate of skin grafts/flaps and postoperative wound infections were evaluated using the Vancouver Scar Scale (VSS) for scar scoring at 6 mo after surgery, as well as the sensory injury grading method and two-point resolution test to assess the recovery of skin sensation at 6 mo. The satisfaction of the two groups of patients was also compared. RESULTS: Wound healing time in the observation group was significantly longer than that in the control group (P < 0.05, 27.92 ± 3.25 d vs 19.68 ± 6.91 d); there was no significant difference in the survival rate of skin grafts/flaps between the two patient groups (P > 0.05, 95.1 ± 5.0 vs 96.3 ± 5.6). The interval between two surgeries (20.0 ± 4.3 d) and hospital stay (21.0 ± 10.1 d) in the observation group were both significantly shorter than those in the control group (27.5 ± 9.3 d) and (28.4 ± 17.7 d), respectively (P < 0.05). In comparison to postoperative infection (23.5%) and subcutaneous hematoma (11.8%) in the control group, these were considerably lower at (10.2%) and (6.1%) in the observation group. When comparing the two patient groups at six months post-surgery, the excellent and good rate of sensory recovery (91.8%) was significantly higher in the observation group than in the control group (76.5%) (P < 0.05). There was also no statistically significant difference in two point resolution (P > 0.05). The VSS score in the observation group (2.91 ± 1.36) was significantly lower than that in the control group (5.96 ± 1.51), and group satisfaction was significantly higher (P < 0.05, 90.1 ± 6.3 vs 76.3 ± 5.2). CONCLUSION: The combination of artificial dermis and autologous skin grafting for the treatment of hand tendon exposure wounds has a satisfactory therapeutic effect. It is a safe, effective, and easy to operate treatment method, which is worthy of clinical promotion.

2.
Sci Rep ; 13(1): 13931, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626167

RESUMO

Plant-derived nanovesicles (NVs) and extracellular vesicles (EVs) are the next generation of nanocarrier platforms for biotherapeutics and drug delivery. EVs exist not only in the extracellular space, but also within the cell wall. Due to the limitations of existing isolation methods, the EVs extraction efficiency is low, and a large amount of plant material is wasted, which is of concern for rare and expensive medicinal plants. We proposed and validated a novel method for isolation of plant EVs by enzyme degradation of the plant cell wall to release the EVs. The released EVs can easily be collected. The new method was used for extraction of EVs from the roots of Morinda officinalis (MOEVs). For comparison, nanoparticles from the roots (MONVs) were extracted using the grinding method. The new method yielded a greater amount of MOEVs, and the vesicles had a smaller diameter compared to MONVs. Both MOEVs and MONVs were readily absorbed by endothelial cells without cytotoxic effect and promoted the expression of miR-155. The promotion of miR-155 by MOEVs was dose-dependent. More importantly, we found that MOEVs and MONVs were enriched toward bone tissue. These results support our hypothesis that EVs in plants could be efficiently extracted by enzymatic cell wall digestion and confirm the potential of MOEVs as therapeutic agents and drug carriers.


Assuntos
Vesículas Extracelulares , MicroRNAs , Células Endoteliais , Espaço Extracelular , Osso e Ossos
3.
Medicine (Baltimore) ; 102(7): e32903, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36800609

RESUMO

To explore the effect of individualized comfortable nursing on prognosis of vacuum sealing drainage (VSD) in patients with orthopedic trauma. 110 patients with orthopedic trauma VSD were randomly divided into the control group and the observation group, with 55 patients in each group receiving routine care and comfortable care. The wound healing time, visual analog scale, quality of life score, the level of inflammatory factors, the incidence of complications, and patient satisfaction were compared between the 2 groups. The average time of wound healing in the observation group was significantly lower than that in the control group (P < .01). The satisfaction rate in the observation group was significantly higher than that in the control group (P = .029). Meanwhile, the results showed that visual analog scale and quality of life scores in the observation group was significantly improved than that of the control group after receiving intervention (P < .05). After receiving intervention, the levels of TNF-α and IL-6 of patients in both groups were decreased, and the levels of TNF-α and IL-6 in the observation group were significantly decreased than those in the control group. Moreover, the incidence rate of adverse reaction in the observation group was significantly lower than that in the control group (P < .01). Comfortable nursing can reduce the wound healing time, the postoperative pain level, the incidence of complications, and improve patient satisfaction, which is of great significance for the prognosis of VSD in patients with orthopedic trauma.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Humanos , Tratamento de Ferimentos com Pressão Negativa/métodos , Fator de Necrose Tumoral alfa , Interleucina-6 , Qualidade de Vida , Drenagem , Prognóstico
4.
Chemosphere ; 309(Pt 1): 136535, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36150484

RESUMO

The biogas production (BP), volatile fatty acids (VFAs), microbial communities, and microbes' active enzymes were studied upon the addition of biochar (0-1.5%) at 6% and 8% slaughterhouse waste (SHW) loadings. The 0.5% biochar enhanced BP by 1.5- and 1.6-folds in 6% and 8% SHW-loaded reactors, respectively. Increasing the biochar up to 1.5% caused a reduction in BP at 6% SHW. However, the BP from 8% of SHW was enhanced by 1.4-folds at 1.5% biochar. The VFAs production in all 0.5% biochar amended reactors was highly significant compared to control (p-value < 0.05). The biochar addition increased the bacterial and archaeal diversity at both 6% and 8% SHW loadings. The highest number of OTUs at 0.5% biochar were 567 and 525 in 6% and 8% SHW, respectively. Biochar prompted the Clostridium abundance and increased the lyases and transaminases involved in the degradation of lipids and protein, respectively. Biochar addition improved the Methanosaeta and Methanosphaera abundance in which the major enzymes were reductase and hydrogenase. The archaeal enzymes showed mixed acetoclastic and hydrogenotrophic methanogenesis.


Assuntos
Hidrogenase , Liases , Microbiota , Archaea/metabolismo , Biocombustíveis , Anaerobiose , Reatores Biológicos , Matadouros , Metano/metabolismo , Hidrogenase/metabolismo , Bactérias/metabolismo , Ácidos Graxos Voláteis/metabolismo , Liases/metabolismo , Transaminases , Digestão
5.
Bioengineered ; 12(1): 5679-5687, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34524066

RESUMO

Circular RNAs (circRNAs) are emerging as important regulators in bone metabolism, which is mediated by microRNA (miRNA) sponges. However, it is not clear how circRNA regulates osteogenic differentiation of human bone marrow mesenchymal stem cells (hBM-MSCs).Therefore, based on the previous circRNA chip results, hsa_circ_0006766, which is differentially expressed in the osteogenic differentiation of hBM-MSCs, was screened out, and bioinformatics analysis was performed to predict potential target miRNAs. During osteogenic differentiation of hBM-MSCs, hsa_circ_0006766 and its target miRNAs (miR-4739, miR-619-5p, miR-5787, miR-7851-3p, and miR-3192-5p) were detected by quantitative Real Time-PCR (qRT-PCR). Target gene prediction for the differentially expressed target miRNAs was performed, and target genes were validated by dual-luciferase reporter gene assay and qRT-PCR. It is shown that hsa_circ_0006766 was up-regulated and miR-4739 was down-regulated during osteogenic differentiation of hBM-MSCs.Moreover, the target gene Notch2 was predicted to be highly expressed during osteogenic differentiation. And dual-luciferase assay proved that Notch2 was the gene targeting to miR-4739. Taken together, our finding confirmed that hsa_circ_0006766 may act as a major regulatory part in osteogenic differentiation of hBM-MSCs via an hsa_circ_0006766-miR-4739-Notch2 regulatory axis. Accordingly, hsa_circ_0006766 may affect the development of osteoporosis and may thus become a therapeutic target.


Assuntos
Diferenciação Celular/genética , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Osteogênese/genética , RNA Circular/genética , Células Cultivadas , Humanos , MicroRNAs/metabolismo , RNA Circular/metabolismo
6.
Bioresour Technol ; 337: 125383, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34126358

RESUMO

The slaughterhouse waste (SHW) contains high organics which makes SHW a feasible feedstock for anaerobic digestion (AD). The present study systematically assessed the microbiome response and biomethanation along with the production of volatile fatty acids (VFAs) and ammonia under 2%, 4%, 6%, and 8% (w v-1) loadings of SHW in AD. The optimum loading was 2% SHW which resulted in maximum biomethane production and VFAs consumption. A higher SHW concentration (4% and 6%) resulted in a prolonged lag-phase and decreased biomethane production. High VFAs (28.88 g L-1) and ammonia nitrogen (>4 g L-1) accumulation were observed at 8% SHW leading to permanent inhibition of biomethane and methanogenic archaea. An increase in ammonia and VFAs concentration, at 4% and 6% SHW loadings, shifted the methanogenic pathway from acetoclastic to hydrogenotrophic lead by Methanoculleus. Acetoclastic Methanosaeta (77.15%) dominated the reactors loaded with 2% SHW resulting in the highest biomethane production.


Assuntos
Amônia , Microbiota , Matadouros , Anaerobiose , Biocombustíveis , Reatores Biológicos , Digestão , Ácidos Graxos , Metano
7.
Environ Pollut ; 286: 117547, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126517

RESUMO

China is experiencing severe tropospheric ozone pollution, especially during the summer period in cities. Previous studies have assessed the role of meteorological conditions and anthropogenic precursors in shaping the diurnal variation of ozone concentration in some Chinese cities or the spatial patterns of daytime ozone concentration, but less is known about the spatial variation and main regulators of the diurnal cycle of summer ozone concentrations in Chinese cities. Using monitoring data from 367 cities, we analyzed the spatial patterns and main regulators of daytime maximum, nighttime minimum and diurnal difference of summer (June-August) ozone concentration during 2015-2019. National mean values and standard deviations of daytime maximum and nighttime minimum of summer surface ozone concentration were 124.1 ± 27.5 and 33.4 ± 13.0 µg m-3, resulting in a diurnal difference of 90.7 ± 25.2 µg m-3. High values of daytime maximum, nighttime minimum, and diurnal difference of summer ozone concentration occurred in cities in northern China, especially in the North China Plain, and several city agglomerations in southern China. Daytime maximum ozone concentration was higher in cities with higher daytime PM2.5 and NO2 concentrations, lower daytime precipitation and lower elevation. Nighttime minimum ozone concentration increased with lower nighttime precipitation, lower NO2 concentration and CO concentration, higher nighttime maximum PM2.5 concentration and higher elevation. Diurnal difference of ozone concentration increased with lower elevation, lower daytime precipitation, and higher diurnal difference of CO and NO2 concentrations. Our findings highlight different regulators for daytime and nighttime ozone and imply the need of joint regulation of PM2.5 and NO2 emissions to control ozone pollution.


Assuntos
Poluentes Atmosféricos , Ozônio , Poluentes Atmosféricos/análise , China , Cidades , Monitoramento Ambiental , Ozônio/análise , Estações do Ano
8.
J Cancer ; 11(21): 6445-6453, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33033528

RESUMO

The main diagnostic indicators of ovarian cancer (OC), including carbohydrate antigen 125 (CA125) and human epididymis protein 4 (HE4), show good sensitivity and poor specificity or vice versa. This study investigated changes in CA125 and HE4 expression and their correlation in serum-derived exosomes of 55 patients with OC (OC group), 33 patients with malignant tumors (non-OC group), and 55 normal controls (NC group). We compared serum and exosomal CA125 and HE4 levels to determine whether their contents in exosomes were elevated. We also compared the diagnostic efficacy of serum HE4, serum CA125, exosomal CA125, and serum HE4+exosomal CA125 in OC using the receiver operating characteristic (ROC) curve. CA125 levels in serum-derived exosomes in all groups significantly increased (P < 0.0001) compared with serum CA125 levels. HE4 was undetected in exosomes. The ROC curve showed the following values: serum CA125: 0.9093 (area), 87.27% (sensitivity), and 90.91% (specificity); serum HE4: 0.9302, 83.64%, and 94.55%; exosomal CA125: 0.9755, 94.55%, and 92.73%; and serum HE4+exosomal CA125: 0.9861, 96.36%, and 92.73%. In conclusion, CA125 can be detected at higher levels in exosomes than in serum, significantly improving OC diagnosis sensitivity. The serum HE4+exosomal CA125 combination significantly improves OC diagnostic efficiency.

9.
J Cell Mol Med ; 24(16): 9323-9331, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32639111

RESUMO

There is currently a lack of biomarkers to assist the diagnosis and prediction of primary gouty arthritis (PG). Therefore, we evaluated the clinical value of programmed cell death protein 1 (PD-1) mRNA expression in peripheral blood mononuclear cells (PBMCs) of patients with PG. This study included 36 patients with acute phase PG (APPG), 48 with non-acute phase PG (NAPPG), 42 with asymptomatic hyperuricemia (AH) and 79 normal controls (NCs). PD-1 mRNA expression levels were detected by qRT-PCR. PD-1 mRNA expression was statistically analysed by ANOVA or t tests, while correlations between PD-1 mRNA and clinical variables were assessed using Pearson correlation tests. Receiver operator characteristic (ROC) curve analysis was used to evaluate the diagnostic value of PD-1 in different PG stages. PD-1 mRNA expression was significantly lower in patients with APPG than that in NAPPG, AH and NCs (P < 0.01). Correlation analysis revealed that PD-1 mRNA levels correlated negatively with T-score (r = -0.209, P < 0.01). ROC curve analysis showed that serum uric acid (SUA), PD-1 mRNA and both combined displayed higher diagnostic value in patients with PG, NAPPG and APPG compared to that in NCs and patients with non-PG arthritis (NPG). Moreover, ROC curve analysis showed that SUA and PD-1 mRNA had good diagnostic value in APPG, with the greatest diagnostic power when combined. PD-1 mRNA could be a clinical auxiliary diagnostic biomarker for APPG, and the combined use of PD-1 mRNA and SUA is better than that of SUA alone.


Assuntos
Artrite Gotosa/diagnóstico , Biomarcadores/sangue , Leucócitos Mononucleares/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , RNA Mensageiro/metabolismo , Artrite Gotosa/sangue , Artrite Gotosa/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Receptor de Morte Celular Programada 1/genética , RNA Mensageiro/genética , Curva ROC
10.
J Clin Lab Anal ; 34(6): e23223, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32065479

RESUMO

BACKGROUND: Postmenopausal osteoporosis (PMOP) is an estrogen deficiency-induced skeletal disorder. Bone mineral density (BMD) testing is the gold standard for diagnosing osteoporosis. However, its sensitivity for fracture risk assessment is low. Programmed cell death protein 1 (PD-1) is a key immune checkpoint molecule implicated in the pathophysiology of bone remodeling, but its role in osteoporosis has not yet been explored. Thus, this study aimed to assess the expression and diagnostic utility of PD-1 in PMOP. METHODS: A total of 56 patients with PMOP and 37 postmenopausal healthy controls (NC) were enrolled in the study. Peripheral blood mononuclear cells (PBMCs) were isolated by Ficoll density gradient centrifugation, and PD-1 expression was measured by quantitative polymerase chain reaction (qPCR). Pearson's correlation test was performed to explore the associations between PD-1 level and clinical variables, while receiver operating characteristic (ROC) curve analysis was used to evaluate the potential diagnostic value of PD-1 in patients with PMOP. RESULTS: We found that PD-1 level was significantly upregulated in the PBMCs of PMOP patients than those of NC (P = .016). PD-1 expression was positively correlated with C-reactive protein (CRP) levels. ROC curve analysis showed that PD-1 had certain diagnostic value for PMOP (area under the curve = 0.65, standard error = 0.06, 95% confidence interval [0.53,0.76], P = .016), with a sensitivity and specificity of 44.64% and 81.08%, respectively. CONCLUSION: Programmed cell death protein 1 is significantly upregulated in the PBMCs of PMOP patients and has certain diagnostic value for PMOP.


Assuntos
Leucócitos Mononucleares/metabolismo , Osteoporose Pós-Menopausa/sangue , Receptor de Morte Celular Programada 1/sangue , Idoso , Biomarcadores/sangue , Sedimentação Sanguínea , Densidade Óssea , Remodelação Óssea , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/etiologia , Curva ROC
11.
Cell Physiol Biochem ; 46(6): 2508-2516, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29742503

RESUMO

BACKGROUND/AIMS: Circular RNAs (circRNAs) serve as potential diagnostic biomarkers. In this study, we aimed to identify a potential biomarker from peripheral blood mononuclear cells (PBMCs) of patients with postmenopausal osteoporosis (PMOP). METHODS: CircRNA expression in PBMCs from three pairs of samples from PMOP patients and controls was initially detected by circRNA microarray. The changes in selected circRNAs in PBMCs from 28 PMOP patients and 21 age- and sex-matched controls were confirmed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Next, samples from 30 PMOP patients and 20 controls were used for further verification. Pearson correlation test was performed to assess the correlation between circRNAs and clinical variables. The area under the receiver operator characteristic (ROC) curve was calculated to evaluate the diagnostic value. RESULTS: Six differentially expressed circRNAs were identified by chip microarray analysis, of which only hsa_circ_0001275 showed consistency and statistical significance in qRT-PCR. The correlation analysis between age, body weight, height, WBC, lymphocyte and monocyte count, bone density, T-score, ß-CROSSL, OSTEOC, and TP1NP showed that hsa_circ_0001275 was negatively correlated with T-score. ROC curves showed that hsa_circ_0001275 has significant diagnostic value in PMOP (AUC=0.759, P< 0.001). CONCLUSION: This study suggests that hsa_circ_0001275 may serve as a potential diagnostic biomarker for PMOP.


Assuntos
Osteoporose Pós-Menopausa/diagnóstico , RNA/genética , Transcriptoma , Idoso , Regulação para Baixo , Feminino , Marcadores Genéticos/genética , Humanos , Leucócitos Mononucleares/metabolismo , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/genética , RNA Circular , Curva ROC , Regulação para Cima
12.
Sci Rep ; 5: 11203, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-26110831

RESUMO

China's forests are characterized by young age, low carbon (C) density and a large plantation area, implying a high potential for increasing C sinks in the future. Using data of provincial forest area and biomass C density from China's forest inventories between 1994 and 2008 and the planned forest coverage of the country by 2050, we developed a stage-classified matrix model to predict biomass C stocks of China's forests from 2005 to 2050. The results showed that total forest biomass C stock would increase from 6.43 Pg C (1 Pg = 10(15) g) in 2005 to 9.97 Pg C (95% confidence interval: 8.98 ~ 11.07 Pg C) in 2050, with an overall net C gain of 78.8 Tg C yr(-1) (56.7 ~ 103.3 Tg C yr(-1); 1 Tg = 10(12) g). Our findings suggest that China's forests will be a large and persistent biomass C sink through 2050.


Assuntos
Biomassa , Carbono/análise , Modelos Teóricos , China , Ecossistema , Florestas
13.
Proc Natl Acad Sci U S A ; 111(26): 9527-32, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24979781

RESUMO

Forests in the middle and high latitudes of the northern hemisphere function as a significant sink for atmospheric carbon dioxide (CO2). This carbon (C) sink has been attributed to two processes: age-related growth after land use change and growth enhancement due to environmental changes, such as elevated CO2, nitrogen deposition, and climate change. However, attribution between these two processes is largely controversial. Here, using a unique time series of an age-class dataset from six national forest inventories in Japan and a new approach developed in this study (i.e., examining changes in biomass density at each age class over the inventory periods), we quantify the growth enhancement due to environmental changes and its contribution to biomass C sink in Japan's forests. We show that the growth enhancement for four major plantations was 4.0∼7.7 Mg C⋅ha(-1) from 1980 to 2005, being 8.4-21.6% of biomass C sequestration per hectare and 4.1-35.5% of the country's total net biomass increase of each forest type. The growth enhancement differs among forest types, age classes, and regions. Our results provide, to our knowledge, the first ground-based evidence that global environmental changes can increase C sequestration in forests on a broad geographic scale and imply that both the traits and age of trees regulate the responses of forest growth to environmental changes. These findings should be incorporated into the prediction of forest C cycling under a changing climate.


Assuntos
Sequestro de Carbono/fisiologia , Meio Ambiente , Árvores/crescimento & desenvolvimento , Fatores Etários , Biomassa , Geografia , Japão , Modelos Biológicos , Análise de Regressão
14.
Glob Chang Biol ; 20(6): 2019-30, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24464906

RESUMO

Forests play an important role in regional and global carbon (C) cycles. With extensive afforestation and reforestation efforts over the last several decades, forests in East Asia have largely expanded, but the dynamics of their C stocks have not been fully assessed. We estimated biomass C stocks of the forests in all five East Asian countries (China, Japan, North Korea, South Korea, and Mongolia) between the 1970s and the 2000s, using the biomass expansion factor method and forest inventory data. Forest area and biomass C density in the whole region increased from 179.78 × 10(6) ha and 38.6 Mg C ha(-1) in the 1970s to 196.65 × 10(6) ha and 45.5 Mg C ha(-1) in the 2000s, respectively. The C stock increased from 6.9 Pg C to 8.9 Pg C, with an averaged sequestration rate of 66.9 Tg C yr(-1). Among the five countries, China and Japan were two major contributors to the total region's forest C sink, with respective contributions of 71.1% and 32.9%. In China, the areal expansion of forest land was a larger contributor to C sinks than increased biomass density for all forests (60.0% vs. 40.0%) and for planted forests (58.1% vs. 41.9%), while the latter contributed more than the former for natural forests (87.0% vs. 13.0%). In Japan, increased biomass density dominated the C sink for all (101.5%), planted (91.1%), and natural (123.8%) forests. Forests in South Korea also acted as a C sink, contributing 9.4% of the total region's sink because of increased forest growth (98.6%). Compared to these countries, the reduction in forest land in both North Korea and Mongolia caused a C loss at an average rate of 9.0 Tg C yr(-1), equal to 13.4% of the total region's C sink. Over the last four decades, the biomass C sequestration by East Asia's forests offset 5.8% of its contemporary fossil-fuel CO2 emissions.


Assuntos
Sequestro de Carbono , Florestas , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Biomassa , Carbono/metabolismo , Ásia Oriental , Estações do Ano
15.
Sci China Life Sci ; 56(7): 661-71, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23722235

RESUMO

Forests play a leading role in regional and global carbon (C) cycles. Detailed assessment of the temporal and spatial changes in C sinks/sources of China's forests is critical to the estimation of the national C budget and can help to constitute sustainable forest management policies for climate change. In this study, we explored the spatio-temporal changes in forest biomass C stocks in China between 1977 and 2008, using six periods of the national forest inventory data. According to the definition of the forest inventory, China's forest was categorized into three groups: forest stand, economic forest, and bamboo forest. We estimated forest biomass C stocks for each inventory period by using continuous biomass expansion factor (BEF) method for forest stands, and the mean biomass density method for economic and bamboo forests. As a result, China's forests have accumulated biomass C (i.e., biomass C sink) of 1896 Tg (1 Tg=10(12) g) during the study period, with 1710, 108 and 78 Tg C in forest stands, and economic and bamboo forests, respectively. Annual forest biomass C sink was 70.2 Tg C a(-1), offsetting 7.8% of the contemporary fossil CO2 emissions in the country. The results also showed that planted forests have functioned as a persistent C sink, sequestrating 818 Tg C and accounting for 47.8% of total C sink in forest stands, and that the old-, mid- and young-aged forests have sequestrated 930, 391 and 388 Tg C from 1977 to 2008. Our results suggest that China's forests have a big potential as biomass C sink in the future because of its large area of planted forests with young-aged growth and low C density.


Assuntos
Biomassa , Sequestro de Carbono , Carbono/química , Árvores/crescimento & desenvolvimento , Ciclo do Carbono , China , Mudança Climática , Ecossistema , Monitoramento Ambiental/métodos , Geografia , Sasa , Fatores de Tempo
16.
Sci China Life Sci ; 53(7): 776-83, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20697867

RESUMO

China's forests are characterized by young forest age, low carbon density and a large area of planted forests, and thus have high potential to act as carbon sinks in the future. Using China's national forest inventory data during 1994-1998 and 1999-2003, and direct field measurements, we investigated the relationships between forest biomass density and forest age for 36 major forest types. Statistical approaches and the predicted future forest area from the national forestry development plan were applied to estimate the potential of forest biomass carbon storage in China during 2000-2050. Under an assumption of continuous natural forest growth, China's existing forest biomass carbon (C) stock would increase from 5.86 Pg C (1 Pg=10(15) g) in 1999-2003 to 10.23 Pg C in 2050, resulting in a total increase of 4.37 Pg C. Newly planted forests through afforestation and reforestation will sequestrate an additional 2.86 Pg C in biomass. Overall, China's forests will potentially act as a carbon sink for 7.23 Pg C during the period 2000-2050, with an average carbon sink of 0.14 Pg C yr(-1). This suggests that China's forests will be a significant carbon sink in the next 50 years.


Assuntos
Biomassa , Carbono , Árvores , Biodiversidade , China
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