Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Environ Sci Technol ; 58(14): 6258-6273, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38450439

RESUMEN

Contamination of small-sized plastics is recognized as a factor of global change. Nanoplastics (NPs) can readily enter organisms and pose significant ecological risks. Arbuscular mycorrhizal (AM) fungi are the most ubiquitous and impactful plant symbiotic fungi, regulating essential ecological functions. Here, we first found that an AM fungus, Rhizophagus irregularis, increased lettuce shoot biomass by 25-100% when exposed to positively and negatively charged NPs vs control, although it did not increase that grown without NPs. The stress alleviation was attributed to the upregulation of gene expressions involving phytohormone signaling, cell wall metabolism, and oxidant scavenging. Using a root organ-fungus axenic growth system treated with fluorescence-labeled NPs, we subsequently revealed that the hyphae captured NPs and further delivered them to roots. NPs were observed at the hyphal cell walls, membranes, and spore walls. NPs mediated by the hyphae were localized at the root epidermis, cortex, and stele. Hyphal exudates aggregated positively charged NPs, thereby reducing their uptake due to NP aggregate formation (up to 5000 nm). This work demonstrates the critical roles of AM fungus in regulating NP behaviors and provides a potential strategy for NP risk mitigation in terrestrial ecosystems. Consequent NP-induced ecological impacts due to the affected AM fungi require further attention.


Asunto(s)
Micorrizas , Micorrizas/metabolismo , Microplásticos , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Hifa , Ecosistema , Expresión Génica
2.
J Exp Bot ; 73(1): 50-67, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34610119

RESUMEN

Rice polluted by metal(loid)s, especially arsenic (As) and cadmium (Cd), imposes serious health risks. Numerous studies have demonstrated that the obligate plant symbionts arbuscular mycorrhizal fungi (AMF) can reduce As and Cd concentrations in rice. The behaviours of metal(loid)s in the soil-rice-AMF system are of significant interest for scientists in the fields of plant biology, microbiology, agriculture, and environmental science. We review the mechanisms of As and Cd accumulation in rice with and without the involvement of AMF. In the context of the soil-rice-AMF system, we assess and discuss the role of AMF in affecting soil ion mobility, chemical forms, transport pathways (including the symplast and apoplast), and genotype variation. A potential strategy for AMF application in rice fields is considered, followed by future research directions to improve theoretical understanding and encourage field application.


Asunto(s)
Arsénico , Micorrizas , Oryza , Contaminantes del Suelo , Cadmio/análisis , Hongos , Raíces de Plantas/química , Suelo , Microbiología del Suelo
3.
J Environ Manage ; 225: 17-24, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30071363

RESUMEN

Restoration of disturbed habitats (e.g., landfills and mine tailings) is important to recover ecosystem services. Arbuscular mycorrhizal (AM) fungal community is an important indicator of ecological performance of ecosystems. Rhizospheric soils were collected in two sites (A1 and A2) within the restored area of a landfill (18 yrs after restoration), and two sites (B and C, serving as control) in the adjacent natural area. Soil properties were analysed. AM fungal communities in soils were analysed by sequencing 18S small subunit rRNA gene. Results showed that genera Glomus (the most abundant, relative abundance: 10-24%), Paraglomus and Rhizophagus were commonly found at all sites. Acaulospora and Redeckera were found exclusively at natural sites, while Scutellospora only at the restored site. On average, AM fungal species richness was lower (87 operational taxonomy units, OTUs), while diversity was higher (Shannon index 3.2) in restored site, compared with control (107 OTUs, Shannon index 2.8). The structure of the AM fungal communities was influenced by soil nitrogen and cation exchange capacity. The restored sites possessed a more phylogenetically heterogeneous fungal community than that in natural sites. AM fungal community at restored sites clearly deviated from that at natural sites, indicating that current restoration practice is certainly inadequate. The trend of ecological succession could be significantly influenced by rehabilitation methods, such as adjustment of initial soil properties and selection of plant species. This study highlights the necessity of assessing AM fungal community during ecological restoration for sustainable ecosystem, in addition to plant and bacteria.


Asunto(s)
Micorrizas , Microbiología del Suelo , Instalaciones de Eliminación de Residuos , Biodiversidad , Ecosistema , Suelo
4.
Environ Sci Pollut Res Int ; 31(30): 42614-42639, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38900405

RESUMEN

Anthropogenic activities have caused irreversible consequences on our planet, including climate change and environmental pollution. Nevertheless, reducing greenhouse gas (GHG) emissions and capturing carbon can mitigate global warming. Biochar and hydrochar are increasingly used for soil remediation due to their stable adsorption qualities. As soil amendments, these materials improve soil quality and reduce water loss, prevent cracking and shrinkage, and interact with microbial communities, resulting in a promising treatment method for reducing gas emissions from the top layer of soil. However, during long-term studies, contradictory results were found, suggesting that higher biochar application rates led to higher soil CO2 effluxes, biodiversity loss, an increase in invasive species, and changes in nutrient cycling. Hydrochar, generated through hydrothermal carbonization, might be less stable when introduced into the soil, which could lead to heightened GHG emissions due to quicker carbon breakdown and increased microbial activity. On the other hand, biochar, created via pyrolysis, demonstrates stability and can beneficially impact GHG emissions. Biochar could be the preferred red option for carbon sequestration purposes, while hydrochar might be more advantageous for use as a gas adsorbent. This review paper highlights the ecological impact of long-term applications of biochar and hydrochar in soil. In general, using these materials as soil amendments helps establish a sustainable pool of organic carbon, decreasing atmospheric GHG concentration and mitigating the impacts of climate change.


Asunto(s)
Carbón Orgánico , Suelo , Carbón Orgánico/química , Suelo/química , Cambio Climático , Gases de Efecto Invernadero
5.
Sci Total Environ ; 929: 172574, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38641094

RESUMEN

Environmental pollution and poor feed quality pose potential threats to aquatic organisms and human health, representing challenges for the aquaculture industry. In light of the rising demand for aquatic organisms, there is an urgent need to improve aquacultural production and protect the products from contamination. Char, a carbonaceous material derived through pyrolysis of organic carbon-rich biomass, has proven advantages in soil, air, and water remediation. While char's performance and the associated physicochemical characteristics depend strongly on the pyrolysis temperature, residence time, and feedstock type, char generally shows advantages in pollutant removal from the environment and livestock. This enables it to enhance the health and growth performance of livestock. Given the growing attention to char application in aquaculture in recent years, this review summarises major studies on three applications: aquacultural water treatment, sediment remediation, and char-feed supplement. Most of these studies have demonstrated char's positive effects on pollutant removal from organisms and aquacultural environments. Moreover, adopting char as fish feed can improve fish growth performance and the condition of their intestinal villi. However, due to insufficient literature, further investigation is needed into the mechanistic aspects of pollutants removal in aquatic organisms by char as a feed additive, such as the transportation of char inside aquatic organisms, the positive and negative effects of char on these products, and how char alters the gut microbiota community of these products. This paper presents an overview of the current application of char in aquaculture and highlights the research areas that require further investigation to enrich future studies.


Asunto(s)
Acuicultura , Carbón Orgánico , Acuicultura/métodos , Carbón Orgánico/química , Alimentación Animal/análisis , Animales , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Restauración y Remediación Ambiental/métodos , Peces
6.
Plants (Basel) ; 12(8)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37111922

RESUMEN

Cabbage grown in contaminated soils can accumulate high levels of arsenic (As) in the edible parts, posing serious health risks. The efficiency of As uptake varies drastically among cabbage cultivars, but the underlying mechanisms are not clear. We screened out low (HY, Hangyun 49) and high As accumulating cultivars (GD, Guangdongyizhihua) to comparatively study whether the As accumulation is associated with variations in root physiological properties. Root biomass and length, reactive oxygen species (ROS), protein content, root activity, and ultrastructure of root cells of cabbage under different levels of As stress (0 (control), 1, 5, or 15 mg L-1) were measured As results, at low concentration (1 mg L-1), compared to GD, HY reduced As uptake and ROS content, and increased shoot biomass. At a high concentration (15 mg L-1), the thickened root cell wall and higher protein content in HY reduced arsenic damage to root cell structure and increased shoot biomass compared to GD. In conclusion, our results highlight that higher protein content, higher root activity, and thickened root cell walls result in lower As accumulation properties of HY compared to GD.

7.
Huan Jing Ke Xue ; 43(2): 1004-1014, 2022 Feb 08.
Artículo en Zh | MEDLINE | ID: mdl-35075874

RESUMEN

Clarifying the absorption dynamics of heavy metal(loid)s by crops under different cultivation methods is critical for risk management and control for heavy metal pollution. Here, taking carrots as an example, the pH, cation exchange capacity (CEC), and contents of heavy metals in soil and carrots were analyzed. We compared the absorption and transport characteristics of six metal(loid)s (As, Cd, Cr, Cu, Pb, and Zn) during the three key growth periods under greenhouse and open-field cultivation methods. In addition, the effects of planting methods on carrot biomass and heavy metal content over time were studied, and a health risk assessment was conducted. The results showed that the greenhouse and open-field cultivation methods had the following in common:① As the carrots continuously grew, the metal uptake and biomass in the belowground part (edible part) and the metal(loid) concentrations in the aboveground and belowground parts both showed trends of increasing first and then decreasing or stabilizing. ② The absorption of As, Cd, Cr, and Pb in carrots was mostly accumulated in the aboveground part. ③ The content of Cd in the edible part exceeded the standard, and the total target hazard quotient was>1, indicating potential adverse health risks, most of which were contributed by As and Cd. Compared to that under open-field, the short-term greenhouse cultivation had a harvest time approximately 15 d earlier. The As, Cd, and Pb concentrations in the aboveground part during the seedling and fast-growing periods were significantly lower in the greenhouse than that in the open-field (P<0.05) but did not differ between greenhouse and open-field (except As) at the mature stage. The concentrations of As and Cd in the belowground part of greenhouse carrots were lower in the greenhouse than those of carrots grown in the open-field at the seedling stage (P<0.05). The absorption of As and Cd was decreased significantly from 0 to 95 d (P<0.05), and there was no significant difference in the metal concentration and absorption in the rest of the growth stages. The bioconcentration factors (BCF) of As, Cd, and Pb in the aboveground part in all stages and those of As and Cd in the belowground part in the seedling stage were lower in the greenhouse than that in the open-field. This study emphasizes the possibility of short-term changes in cultivation mode to reduce the risks of metal(loid)s in contaminated farmland vegetables.


Asunto(s)
Daucus carota , Metales Pesados , Contaminantes del Suelo , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis , Verduras
8.
J Hazard Mater ; 420: 126165, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34273883

RESUMEN

The low- and high-arsenic (As) transferring cultivars (LTC and HTC) of cabbage showed significant differences in As uptake and distribution. We hypothesise that chemistry of root cell wall matrix plays a critical role. LTC and HTC were treated with As and grown for 60 days. As concentration and distribution at subcellular and cell wall component (pectin, hemicellulose and lignin) levels were determined. Remodelling enzymes (PME and PAL) and functional groups of cell wall were analysed. Results showed that shoot biomass of LTC was not affected by As. Less As was accumulated in shoot of LTC than HTC. LTC allocated more As in root and majority of As was deposited in cell wall. LTC had more hemicellulose 1 (HC1) and lignin, PME and PAL activities. The uronic acid contents of pectin, HC1 or HC2 were all positively (P < 0.05) correlated with As concentrations in each component, respectively. Chemistry of LTC root cell wall was remodelled in terms of changes in porosity, HC and lignin contents, and functional groups, which potentially exerted coupling effects on As entering and deposition. The LTC can restrain As in roots through changing characteristics of root cell wall matrix.


Asunto(s)
Arsénico , Brassica , Contaminantes del Suelo , Cadmio/análisis , Pared Celular/química , Raíces de Plantas/química , Contaminantes del Suelo/análisis
9.
J Hazard Mater ; 416: 125894, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492832

RESUMEN

The chemistry of root cell wall of rice could be changed by inoculation of arbuscular mycorrhizal fungi (AMF). Hydroponic experiments were conducted to investigate the roles of such changes on cadmium (Cd) uptake and distribution in rice. Results showed that inoculation of AM fungus Rhizophagus intraradices (RI) significantly enhanced (p < 0.05) shoot biomass, plant height and root length of rice, and decreased Cd concentration in shoot and root under Cd stress. Moreover, Cd in root was mainly found in pectin and hemicellulose 1 (HC1) components of root cell wall. Inoculation of RI increased the levels of pectin, HC1 and lignin content, accompanied by the increments of L-phenylalanine ammonia-lyase (PAL) and pectin methylesterase (PME) activities. Results of Fourier transform infrared spectroscopy further showed that more hydroxyl and carboxyl groups in root cell wall were observed in mycorrhizal treatment, compared with control. This study demonstrates that cell wall components could be the locations for Cd fixation, which reduced Cd transportation from root to shoot. Inoculation of AMF may remodel root cell wall biosynthesis and affect the characteristics of Cd fixation. The entering and fixing mechanisms should be further studied.


Asunto(s)
Micorrizas , Oryza , Contaminantes del Suelo , Cadmio/análisis , Pared Celular/química , Hongos , Raíces de Plantas/química , Contaminantes del Suelo/análisis
10.
Sci Total Environ ; 717: 137133, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32062262

RESUMEN

Landfills, as the most common approach to disposing of municipal solid waste worldwide, disturb native ecosystems and create a need for ecological restoration. The restoration of landfill cover with biochar has shown immediate potential to improve soil microbial functions within one year. However, such characteristics could change after a longer period of time. Here, soil properties, microbial communities, and microbial functional genes related to nutrient cycling were investigated three years after the biochar amendment of the topsoil of a subtropical landfill cover. The results showed that the levels of soil organic matter, water content, total carbon (C), total nitrogen (N) and total phosphorus (P) of biochar-amended soils were higher than those of control soil. Different soil microbial community structures were observed in the biochar-amended and control soils. Nine phyla, including Proteobacteria and Acidobacteria, but not Actinobacteria or Chloroflexi, were enriched in the biochar-amended soil. Although the impact of biochar on shaping microbial communities increased after a longer period of restoration, no differences were observed in soils that were amended using different biochar:soil ratios. The abundances of functional genes related to C and N cycling decreased, whereas those of genes related to P cycling were higher in soils that received biochar amendment. This finding suggests that compared with the control soil, biochar-amended soils were less active in processes involved in C and N cycling but enhanced in processes related to P cycling. This study can serve as a reference for future ecological restoration of degraded lands using biochar.


Asunto(s)
Microbiota , Microbiología del Suelo , Suelo , Carbón Orgánico , Instalaciones de Eliminación de Residuos
11.
Chemosphere ; 199: 603-611, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29459350

RESUMEN

Polybrominated diphenyl ethers (PBDEs, tri-to hepta-BDEs) and Dechlorane Plus (DP) in multiple samples (soil, sediment, road dust, and PM2.5 particles) in historical locations of our previous work in Guiyu (electronic-waste recycling town) in southeastern China were investigated in 2014. Ten years later, PBDEs and DP were detected in 100% of the samples. Æ©3-7PBDEs were still relatively great, ranging from 1.2 × 101 to 2.1 × 103 ng/g dry weight (dw) in soil, 2.1 to 3.2 × 103 ng/g dw in sediment, 1.0 × 101 to 1.1 × 104 ng/g dw in road dust, which were a little less than or close to those measured in 2004. However, Æ©3-7PBDEs in PM2.5 (5.0 × 102 to 8.4 × 102 pg/m3) were significantly lower in 2014. BDE-47, -99, -153, and -183 were predominant congeners, which were also predominant PBDEs reported in Guiyu (2006-2008). Greater proportions of lesser-brominated BDEs were predominant in PM2.5 than other samples. DP was detected in 100% of the samples collected with high levels. Total syn-DP and anti-DP concentrations were 3.8 to 2.1 × 103 ng/g dw in soil, 1.1 × 103 to 7.2 × 103 ng/g dw in sediment, 1.4 × 101 to 1.1 × 103 ng/g dw in road dust, and 1.8 × 102 and 1.7 × 102 pg/m3 in PM2.5. Most of the fractions of anti-DP (fanti) (70%-80%) were consistent among samples. The health risk assessment showed that hazard indexes (HIs) of PBDEs or DPs for child or adult were all lower than 0.16.


Asunto(s)
Residuos Electrónicos/análisis , Monitoreo del Ambiente/métodos , Éteres Difenilos Halogenados/análisis , Hidrocarburos Clorados/análisis , Compuestos Policíclicos/análisis , Reciclaje/métodos , Adulto , Niño , China , Polvo/análisis , Humanos , Contaminantes del Suelo/análisis
12.
Sci Total Environ ; 644: 963-975, 2018 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-30743893

RESUMEN

Landfills commonly occupy large areas of land that may be ecologically important. Ecological restoration of landfill cover is a necessary approach to rebuild sustainable habitats. However, unfavourable soil conditions and invasion by exotic plants in certain regions hinder the restoration. In this study, the effects of biochar as a soil amendment on the restoration of a landfill cover were investigated under field condition. Topsoils of a landfill cover in the subtropical region (Shenzhen, China) were mixed with 0, 5 and 10% (v/v) of biochar. Soil pH, electronic conductivity, organic matter, total organic carbon, water content, total N and total P were enhanced by biochar amendment. After nine months of self-succession, plant productivity, species richness and diversity were enhanced by biochar. The structures of soil bacterial and arbuscular mycorrhizal (AM) fungal communities were changed, and species richness and diversity were moderately promoted. Enhanced plant growth and diversity were probably attributed to a number of enhanced bacterial functions related to nutrient cycling including aerobic ammonia oxidation, aerobic nitrite oxidation, nitrification, sulphur respiration, nitrate respiration, nitrogen respiration, ureolysis, chemoheterotrophy and fermentation. The higher abundances of bacteria Streptomyces sp. and Pseudomonas sp. in biochar treatments potentially enhanced the AM fungal diversity. The bacterial diversity was more related to the soil properties, especially pH, than AM fungi. Continuous monitoring is necessary to track the changes of species composition and ecological functions over time. This is the first comprehensive study on the effects of biochar on the ecological performance of a man-made ecosystem. In addition to agricultural application, biochar can be used for restoring degraded lands.


Asunto(s)
Carbón Orgánico , Eliminación de Residuos/métodos , Instalaciones de Eliminación de Residuos , Agricultura , Fenómenos Fisiológicos Bacterianos , China , Ecología , Ecosistema , Micorrizas , Nitrificación , Nitrógeno , Plantas , Microbiología del Suelo
13.
Chin J Traumatol ; 10(2): 86-9, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17371618

RESUMEN

OBJECTIVE: To introduce a practical, economical, and time-saving method to stain (with osmic acid) the myelin sheath in normal and regenerated peripheral nerves. METHODS: A total of 12 Sprague Dawley rats, weighing 250-320 g (mean equal to 276 g+/-38 g), were divided into two groups: a normal nerve group (n equal to 6) and a regenerated nerve group (n equal to 6). In the normal nerve group, the ventral and dorsal roots of L(4) to L(6) and their sciatic nerves were harvested for histological analysis. While in the regenerated nerve group, the right sciatic nerves were severed and then repaired with an epineurial microsuture method. The repaired nerves were harvested 12 weeks postoperatively. All the specimens were fixed in 4% paraformaldehyde and transferred to 2% osmic acid for 3-5 days. Then the specimens were kept in 75% alcohol before being embedded in paraffin. The tissues were cut into sections of 3 micromolar in thickness with a conventional microtome. RESULTS: Under a light microscope, myelin sheaths were clearly visible at all magnifications in both groups. They were stained in clear dark colour with a light yellow or colorless background, which provided high contrast images to allow reliable morphometric measurements. Morphological assessment was made in both normal and regenerated sciatic nerves. The ratios of the myelin area to the fibre area were 60.28%+/-7.66% in the normal nerve group and 51.67%+/-6.85% in the regenerated nerve group, respectively (P less than 0.01). CONCLUSIONS: Osmic acid staining is easy to perform and a very clear image for morphometrical assessment is easy to obtain. Therefore, it is a reliable technique for quantitative evaluation of nerve morphology.


Asunto(s)
Vaina de Mielina , Regeneración Nerviosa , Tetróxido de Osmio , Nervios Periféricos/anatomía & histología , Coloración y Etiquetado/métodos , Animales , Vaina de Mielina/patología , Nervios Periféricos/patología , Ratas , Ratas Sprague-Dawley , Nervio Ciático/patología , Técnicas de Sutura
15.
Environ Sci Pollut Res Int ; 24(6): 5268-5276, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28004369

RESUMEN

The accumulation, distribution, and speciation of contaminants, such as arsenic, in rice can be affected by soil microorganisms such as arbuscular mycorrhizal fungi (AMF). As a potential measure to control contaminant acquisition in rice, the status and performance of AMF in the field need to be investigated. Root samples of rice plants were collected in seven different cities in Guangdong, Jiangxi, Hubei, and Jiangsu Provinces in China in order to investigate the colonization rate of AMF. The total DNA of the roots was extracted, followed by PCR and sequencing, and further confirmed the existence of AMF. The highest colonization rates (19.5 ± 7.2%) were observed in samples from Huizhou City, Guangdong Province. Sequences of ribosomal DNA derived from Pingtan (PT) and Shuikou (SK) in Huizhou shared a similarity of 73 and 86% to Glomus cf. clarum Att894-7 (FM865542) and "uncultured fungus" (EF434122.1), respectively. The moisture tolerance of the AMF from different sources was tested by subjecting to different levels of water content in the soil. Only AMF from PT, SK, and LJ colonized rice under a condition of 100% of the soil water holding capacity (WHC), but not those isolated from upland plants. The AM colonization rate could be governed by the lighting conditions and temperature. AMF isolated in paddy fields has been shown to have more tolerance to moisture than other upland species. Radial oxygen loss (species and stress dependent) could be an essential factor influencing the colonization rate and requires more investigation.


Asunto(s)
Micorrizas/genética , Oryza/microbiología , Raíces de Plantas/microbiología , Arsénico/análisis , China , Glomeromycota , Suelo , Microbiología del Suelo , Contaminantes del Suelo/análisis
16.
Waste Manag ; 63: 49-57, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27561244

RESUMEN

Engineered sanitary landfills are becoming more and more common worldwide. Ecosystem restoration of capped sanitary landfills is essential to restore the disturbed environment. Comparing plant communities, as well as bacterial communities, in landfills and natural areas, offers an efficient way to assess the restoration status. However, such studies on the restored engineered landfills are limited. Here we present an ecological restoration case in an engineered landfill in a subtropical region. Part of the South East New Territories (SENT) landfill in Hong Kong was capped and restored, by using 16 plant species growing on top of the final cover soil, during 1997-1999. In 2014, plant survey and soil properties analyses were conducted in a restored site (AT) and a natural site (CT, an undisturbed area, serving as a control). The similarity between the biota communities (i.e., plant and soil bacteria) of the two sites was assessed. Plant and soil bacterial communities at AT were significantly different (R=1, P<0.01, ANOSIM) from those at CT. A lower plant diversity but a higher soil bacterial diversity were observed at AT. The soil bacterial community structure was potentially driven by soil pH, moisture content, cation exchange capacity (CEC), N, and P. The engineered landfill had not been restored to an ecosystem similar to the natural environment 15years after restoration. Establishing similar soil properties in the landfill topsoil would be important to achieve a bacterial community similar to the natural area. This study can also offer a quick and inexpensive method for landfill engineers to assess the bacterial restoration of man-made ecosystems using plant and soil properties rather than DNA analyzing techniques.


Asunto(s)
Bacterias/clasificación , Restauración y Remediación Ambiental , Plantas/clasificación , Microbiología del Suelo , Suelo/química , Instalaciones de Eliminación de Residuos , Ecosistema , Hong Kong , Nitrógeno/química
17.
Environ Int ; 96: 65-74, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27608428

RESUMEN

Indoor air pollution is closely related to children's health. Polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DP) transmitted through indoor PM2.5 and dust, along with carbonyl compounds and black carbon (BC) aerosol were analysed in five Hong Kong kindergartens. The results showed that 60% of the median PM2.5 levels (1.3×101 to 2.9×101µg/m3 for indoor; 9.5 to 8.8×101µg/m3 for outdoor) in the five kindergartens were higher than the guidelines set by the World Health Organization (2.5×101µg/m3). Indoor PM2.5 mass concentrations were correlated with outdoor PM2.5 in four of the kindergartens. The PBDEs (0.10-0.64ng/m3 in PM2.5; 0.30-2.0×102ng/g in dust) and DP (0.05-0.10ng/m3 in PM2.5; 1.3-8.7ng/g in dust) were detected in 100% of the PM2.5 and dust samples. Fire retardant levels in the air were not correlated with the levels of dust in this study. The median BC concentrations varied by >7-fold from 8.8×102ng/m-3 to 6.7×103ng/m-3 and cooking events might have caused BC concentrations to rise both indoors and outdoors. The total concentrations of 16 carbonyls ranged from 4.7×101µg/m3 to 9.3×101µg/m3 indoors and from 1.9×101µg/m3 to 4.3×101µg/m3 outdoors, whilst formaldehyde was the most abundant air carbonyl. Indoor carbonyl concentrations were correlated with outdoor carbonyls in three kindergartens. The health risk assessment showed that hazard indexes (HIs) HIs of non-cancer risks from PBDEs and DPs were all lower than 0.08, whilst non-cancer HIs of carbonyl compounds ranged from 0.77 to 1.85 indoors and from 0.50 to 0.97 outdoors. The human intake of PBDEs and DP through inhalation of PM2.5 accounted for 78% to 92% of the total intake. The cancer hazard quotients (HQs) of formaldehyde ranged from 4.5E-05 to 2.1E-04 indoors and from 1.9E-05 to 6.2E-05 outdoors. In general, the indoor air pollution in the five Hong Kong kindergartens might present adverse effects to children, although different schools showed distinct pollution levels, so indoor air quality might be improved through artificial measures. The data will be useful to developing a feasible management protocol for indoor environments.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Éteres Difenilos Halogenados/análisis , Hidrocarburos Clorados/análisis , Compuestos Policíclicos/análisis , Hollín/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire Interior/efectos adversos , Carbono/análisis , Carbono/toxicidad , Preescolar , Polvo/análisis , Monitoreo del Ambiente , Retardadores de Llama/análisis , Retardadores de Llama/toxicidad , Éteres Difenilos Halogenados/toxicidad , Hong Kong , Humanos , Hidrocarburos Clorados/toxicidad , Compuestos Policíclicos/toxicidad , Medición de Riesgo , Instituciones Académicas , Hollín/toxicidad
18.
Environ Sci Pollut Res Int ; 23(8): 7111-25, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26452652

RESUMEN

Due to the increasing concerns on global warming, scarce land for agriculture, and contamination impacts on human health, biochar application is being considered as one of the possible measures for carbon sequestration, promoting higher crop yield and contamination remediation. Significant amount of researches focusing on these three aspects have been conducted during recent years. Biochar as a soil amendment is effective in promoting plant performance and sustainability, by enhancing nutrient bioavailability, contaminants immobilization, and microbial activities. The features of biochar in changing soil physical and biochemical properties are essential in affecting the sustainability of an ecosystem. Most studies showed positive results and considered biochar application as an effective and promising measure for above-mentioned interests. Bio-engineered man-made filled slope and landfill slope increasingly draw the attention of geologists and geotechnical engineers. With increasing number of filled slopes, sustainability, low maintenance, and stability are the major concerns. Biochar as a soil amendment changes the key factors and parameters in ecology (plant development, soil microbial community, nutrient/contaminant cycling, etc.) and slope engineering (soil weight, internal friction angle and cohesion, etc.). This paper reviews the studies on the production, physical and biochemical properties of biochar and suggests the potential areas requiring study in balancing ecology and man-made filled slope and landfill cover engineering. Biochar-amended soil should be considered as a new type of soil in terms of soil mechanics. Biochar performance depends on soil and biochar type which imposes challenges to generalize the research outcomes. Aging process and ecotoxicity studies of biochar are strongly required.


Asunto(s)
Carbón Orgánico/química , Instalaciones de Eliminación de Residuos , Animales , Secuestro de Carbono , Estudios de Factibilidad , Calentamiento Global , Humanos , Hidrocarburos Policíclicos Aromáticos/análisis , Suelo/química , Contaminantes del Suelo/análisis
19.
Zhongguo Gu Shang ; 23(7): 530-3, 2010 Jul.
Artículo en Zh | MEDLINE | ID: mdl-20701131

RESUMEN

OBJECTIVE: Using the method of bleeding from the orbital vein and lancing to make the animal model of trauma, and to observe the influence of reinforcing Qi strength spleen in the expression of bFGF and EGF in the reparative process of raw surface, in order to explore the possible mechanism of reinforcing Qi strength spleen in promoting the rehabilitation of soft tissue. METHODS: Forty healthly adult SD rats were made to be traumatic model using the method of bleeding from the orbital vein and lancing. After operation, there were 33 rats survival, which were divided into the reinforcing Qi strength spleen group, the activating blood circulation to dissipate blood stasis group and the model group randomly. The raw surface and ambient normal skin were taken at the 3rd, 7th and 14th days after operation to detect the expression of bFGF and EGF by immunohistochemical method. RESULTS: At the 3rd, 7th and 14th days after operation, the expression of bFGF and EGF in the tissue of raw surface of the reinforcing Qi strength spleen group and the activating blood circulation to dissipate blood stasis group was obviously higher than that of the model group(P < 0.05). Compared with the activating blood circulation to dissipate blood stasis group, the expression of bFGF and EGF in the tissue of raw surface of the reinforcing Qi strength spleen group was higher (P < 0.05) in the 3rd and 7th day after operation. But in the 14th after operation, there was no significantly difference between reinforcing Qi strength spleen group and activating blood circulation to dissipate blood stasis group. CONCLUSION: The method of reinforcing Qi strength spleen can efficiently promote the expression of bFGF and EGF in raw surface of serious soft tissue injury.


Asunto(s)
Medicamentos Herbarios Chinos/administración & dosificación , Factor de Crecimiento Epidérmico/genética , Factor 2 de Crecimiento de Fibroblastos/genética , Expresión Génica/efectos de los fármacos , Traumatismos de los Tejidos Blandos/tratamiento farmacológico , Bazo/fisiopatología , Animales , Modelos Animales de Enfermedad , Factor de Crecimiento Epidérmico/metabolismo , Femenino , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Humanos , Masculino , Qi , Ratas , Ratas Sprague-Dawley , Traumatismos de los Tejidos Blandos/genética , Traumatismos de los Tejidos Blandos/metabolismo , Traumatismos de los Tejidos Blandos/fisiopatología , Bazo/efectos de los fármacos
20.
Zhongguo Gu Shang ; 22(2): 133-5, 2009 Feb.
Artículo en Zh | MEDLINE | ID: mdl-19281028

RESUMEN

OBJECTIVE: To study the effect and complications of transforaminal lumbar interbody fusion technique. METHODS: The medical records and radiographs of 40 patients undergone transforaminal lumbar interbody fusion between 2005 and 2007 were retrospectively reviewed. There were 49 segments with fusion. Preoperative and 1 year postoperative functional evaluation were graded with ODI and VAS scoring system. The height and angle of the intervertebral space and the fusion status were measured as well. RESULTS: All patients were followed-up for 12 to 24 months with the average of 18 mouths. There were no severity postoperative complications. The operation time averaged 160 min and average blood loss 510 ml. The effect results were excellent in 28 cases, good in 7 and fair in 5. The fusion rate was 100%. One year after operation, the pain relief in the VAS and the reduction of the ODI were significant (P < 0.01), the height and angle of the intervertebral space increased obviously (P < 0.05). Fifteen patients complained low back pain to some extent untill the last follow-up. CONCLUSION: Transforaminal lumbar interbody fusion can achieve satisfactory clinical and radiographic results especially for the failed back surgery syndrome.


Asunto(s)
Fijación Interna de Fracturas/métodos , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Adulto , Anciano , Femenino , Humanos , Vértebras Lumbares/lesiones , Masculino , Persona de Mediana Edad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA