ENVIRONMENTAL POLLUTION
·
2021
·
IF 8.071
Feiyang Xia,Quanwei Yao,Jun Zhang,Dunqiu Wang
Although microplastics are an emerging pollutant of global concern, little is known about the environmental behavior of microplastic in sediments. This study investigated the occurrence and seasonal variation of microplastics in the sediments of Liangfeng River, China with a fluorescence staining method, and then explored the transfer of microplastics at the water and sediment interfaces during resuspension . The results showed that smaller microplastics were detected in the sediments, which were concentrated in the size range of 50–500 μm. Microplastic abundance in the sediments in the dry season were slightly higher than those from the rainy season, and the rainy season promotes the accumulation of smaller microplastics in the sediment along the river-flow direction but not for the dry season. The shape of microplastics were predominantly fibers, followed by fragments and films. Polyethylene was the most abundant polymer, accounting for more than 50% of the total. Microplastics in the surface sediment move both to the overlying water and deeper sediment during the disturbance process. Disturbance-induced resuspension and vertical transport have significant effects on small-sized microplastics (50–500 μm). Small-sized microplastics can potentially migrate and redistribute via resuspension at different temporal and spatial scales, as some extent of resuspension is occurring in most river systems, especially in urban areas with boat traffic.
研究领域:
环境科学
·
生态学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
He-He Tian,Yu-Lian Li,Xu-Song Wang,Xu-Hui Huang,Yu-Ying Zhang,Zi-Chun Zhang,Da-Yong Zhou,Lei Qin
Abalone, a highly sought-after aquatic product, possesses significant nutritional value. In this study, the relationship between aroma characteristics and lipid profile of abalone ( Haliotis discus hannai ) during seasonal fluctuation and thermal processing were profiled via volatolomics and lipidomics. 46 aroma compounds and 371 lipids were identified by HS-SPME-GC–MS and UPLC-Q-Extractive Orbitrap-MS, respectively. Multivariate statistical analysis indicated that carbonyls (aldehydes and ketones) and alcohols were the characteristic aroma compounds of abalone. The fluctuations in the aroma compound and lipid composition of abalone were consistent with the seasonal variation, especially seawater temperature. In addition, based on the correlation analysis, it was found that carbonyls (aldehydes and ketones) and alcohols had a positive correlation with phospholipids (lysophosphatidylethanolamines and lysophosphatidylcholines), while a negative correlation was observed with fatty acyls. These findings suggested that the effect of seasonal variations on the aroma changes of abalone might achieved by modulating the lipids composition of abalone.
研究领域:
食品科学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Frontiers in Public Health
·
2024
·
IF 3
Danchen Wu,Zhijing Ma,Haitao Diao,Wanru Wang,Liu Chen,Dalin Zhou,Jing Yang,Quan Zhen
Polycyclic aromatic hydrocarbons (PAHs) were measured in 342 daily PM10 samples collected in four seasons at a site in Bengbu, China. This study was a qualitative and quantitative investigation of the emission sources of atmospheric PAHs in Bengbu and the spatial distribution of regional PAH sources in PM10 samples. The annual concentrations of the 16 EPA priority PAHs ranged from 1.45 to 62.16 ng/m3, with an annual mean of 7.63 ± 7.38 ng/m3. The seasonal trends during the year were: winter (6.13–62.16 ng/m3, median = 14.99 ng/m3) > autumn (2.01–18.78 ng/m3, median = 4.90 ng/m3) > spring (1.45–19.34 ng/m3, median = 3.32 ng/m3) > summer (1.57–4.27 ng/m3, median = 2.12 ng/m3). The PAHs over the year were dominated by medium-molecular-weight PAHs (39.81%), followed by high-molecular-weight PAHs (35.77%), and low-molecular-weight PAHs (24.42%). The diagnostic ratio method and positive matrix factorization revealed that the PAH sources in Bengbu in spring and summer were industrial emissions, coal and biomass combustion, and traffic emissions; while the sources in autumn and winter were coal and biomass combustion and traffic emissions. According to a backward trajectory clustering analysis and potential source contribution function analysis, Bengbu City was mainly affected by pollution from the northern and northwestern regions in spring, autumn, and winter, while it was more affected by the coastal monsoon in summer. The PAH pollution in Bengbu was most severe in spring, autumn, and winter, and the health risk to the population was also most severe at that time. The health risk to adult males (3.35 × 10−4) was greater than the risk to adult females (3.14 × 10−4), and the health risk to adults was greater than the risk to children (2.52 × 10−4).
研究领域:
环境科学
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ATMOSPHERIC ENVIRONMENT
·
2020
·
IF 4.039
Yunchao Wu,Xiaoping Huang,Zhijian Jiang,Songlin Liu
The phosphorus in precipitation provides a significant fraction of the bioavailable phosphorus to fresh and marine waters. To identify the possible sources and interpret the atmospheric deposition processes of phosphorus, we measured the phosphate oxygen isotopes (δ 18 O P ) in the precipitation monthly from October 2015 to March 2017 in Daya Bay, South China Sea. The isotopic results show that the δ 18 O P values in the dry season (+19.60‰ to +25.80‰, +23.10‰ average) were significantly higher than those in the wet season (+12.52‰ to +20.11‰, +16.73‰ average), indicating a variable contribution from different phosphorus sources to the precipitation between seasons. The δ 18 O P value was primarily influenced by the phosphorus concentrations, rainfall, and air temperature. The exchange of phosphate molecules among phosphorus pools caused isotope dilution (wet season) or enrichment effects (dry season) during the seasonal shifts. The δ 18 O P value of the precipitation and the local end-members indicate that coal combustion (39% ± 16%), biomass burning (22% ± 18%), and soil (17% ± 13%) sources dominate in the dry season, whereas marine sources (28% ± 19%) and coal combustion (24% ± 12%) account for the highest proportion in the wet season using a MixSIAR model. The atmospheric wet deposition flux of phosphorus in Daya Bay was 379.0 μmol m −2 ·yr −1 . The wet deposition of phosphorus exhibits a significant seasonal trend with higher deposition fluxes in the wet season than in the dry season as a result of higher rainfall and source shifts (local sources to marine source) between seasons.
研究领域:
环境科学
·
海洋学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Xianliang Wu,Huijuan Liu,Xuetao Guo,Zhenming Zhang,Jiachun Zhang,Xianfei Huang
An increasing number of researchers have focused on microplastics (MPs) pollution in inland freshwater lakes due to its ecotoxicity, while little is known about the effects of hydrological periods on MPs distribution. Therefore, this study aims to investigate MPs distribution, morphological characteristics and physicochemical indices in various environments in dry and wet periods in Caohai Lake. The results exhibited that cultivated soil, water, and sediment in Caohai Lake have been polluted by MPs in dry and wet periods. There were pellets, fragments, film, and fibers of MPs in both dry and wet periods, and MP foam was additionally found in the wet period. MPs with 0 to 0.5 mm possessed the largest proportion in the five environments in dry and wet periods, followed by MPs with 0.5 to 1 mm and 1 to 5 mm. In Caohai Lake, the black, white, green, red, and transparent MPs in dry period, and black, colourful, grey, red and transparent MPs in wet period were found. The developed structural equation model confirmed that MPs in sediment were probably mainly from soil. There are negative effects of the relative abundance of MPs from cultivated soil to lake water in the dry period, whereas the opposite is true in the wet period. Interestingly, the complex and fast water velocity in the estuary in the wet period led to a lower relative abundance of MPs in its sediment in comparison with the dry period. The distribution model of MPs in estuary and lake water in dry and wet periods is not inconsistent. Our results suggest that the related government department should take measures to reduce the MPs pollution in Caohai Lake, especially from the source.
研究领域:
环境科学
·
生态学
✓ 已验证
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2014
·
IF 3.259
Yinghua Xie,Yunxia Zheng,Xiling Dai,Quanxi Wang,Jianguo Cao,Jianbo Xiao
The seasonal dynamics of the total flavonoid contents in various parts of Dryopteris erythrosora , a traditional Chinese medicinal fern, and their antioxidant activity were investigated. The total flavonoids content in various parts of D. erythrosora showed an obvious seasonal dynamic change. The total flavonoid contents in stems (from 4.3% to 12.5%) were much higher than that in leaves with an average content of 2.01%. In spring, the total flavonoid contents in stems were relatively low, but increased rapidly from summer to winter. However, the seasonal dynamics of total flavonoid contents in leaves showed different model. The total flavonoid contents in the stems showed a negative correlation with that in the leaves from January to July. The correlation coefficient of about −0.7 was obtained. The antioxidant activity of the extracts also altered in proportion to the change of total flavonoid contents. In general, the extracts from stems always showed highest antioxidant potentials and it was suggested that the stems can be used as crude medicine.
研究领域:
植物学
·
药理学
✓ 已验证
DOI
高影响因子
Journal of Aquatic Food Product Technology
·
2020
·
IF 1.02
Yan-Fei Liu,Zi-Xuan Wu,Jing Zhang,Yu-Xin Liu,Zhong-Yuan Liu,Hong-Kai Xie,Kanyasiri Rakariyatham,Da-Yong Zhou
Lipid profile of the oyster Crassostrea talienwhanensis from the Yellow Sea was evaluated based on the seasonal changes in lipid categories, phospholipid (PL) categories, fatty acid (FA) composition, atherogenicity index (IA), thrombogenicity index (IT), and glycerophospholipid (GP) molecular species. We observed that the samples harvested in February contained higher levels of polyunsaturated fatty acid (PUFA) (48.77% of total FAs) and PL (52.12% of total lipids) and had lower IA (0.29). In addition, more than 290 GP molecular species of glycerophosphocholine (GPCho), glycerophosphoethanolamine (GPEtn), glycerophosphoserine (GPSer), and glycerophosphoinositol (GPIns) were determined. The molecular species containing eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) constituted 75.24% of total GPCho in the samples harvested in February. Considering the lipid profile, oyster Crassostrea talienwhanensis harvested in February had better nutritional value.
研究领域:
营养学
·
海洋生物学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENT INTERNATIONAL
·
2023
·
IF 11.8
Feiyang Xia,Qian Tan,Haiguang Qin,Dunqiu Wang,Yanpeng Cai,Jun Zhang
In rivers, riverbeds are considered to have dual properties as a short-term sink and a source of further mobilization for microplastics. To better understand the sources, storage, and fate of microplastics in river systems, this study quantified the formation of microplastic hotspots in riverbeds and seasonal variations in microplastic inventories in riverbeds, especially for small-sized microplastics (<330 µm), with a fluorescence-based protocol. This study provides first-hand measured evidence for the sequestration of microplastics in the riverbed under low-flow conditions and its export from the riverbed under high-flow conditions. The results show that riverbeds in urban areas are still hotspots for microplastic pollution and that high inputs of urban microplastics control microplastic load in its downstream areas. Seasonal rainfall exported 34.86 % (equivalent to 4.34 × 10 11 items/8.57 t) of microplastic pollution from the riverbed, and its removal capacity may be related to the rainfall intensity. Wider riverbeds are conducive to the formation of microplastic hotspots due to the flow slow down. Most importantly, rainfall-driven scouring of the riverbed can enhance the pollution of small-sized microplastics in the riverbed, especially the smallest-size microplastics (<100 µm). Therefore, this study not only contributes reliable information about the sequestration and export of microplastics in the riverbed, but also provides a possible mechanism to explain the lack of small-sized microplastics (<330 µm) in the ocean.
研究领域:
环境科学
·
生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
·
IF 8.9
Fanfan Ju,Liuzhu Chen,Teng Ma,Xiaoli Wang,Zhanqiang Chen,Jiejun Zheng,Xinxing Xia
Studying the geochemical behavior of chlorine is the basis of understanding the chlorine cycle in nature. To explore the spatiotemporal distribution of natural organic chlorine (Cl org ), L layer (litter fall), F–H layer (humification zone), topsoil layer (0–20 cm), and deep soil layer (20–40 cm) samples were collected from 18 sampling sites at different altitudes (851–2918 m) in Shennongjia Forest in May, August, and December. Cl org content was analyzed, and the Cl org stocks were calculated. The major factors affecting the distribution of Cl org were explored. The results revealed that the sum of Cl org content in four layers varied from 7.958 to 184.686 mg/kg, and the highest value was observed in August. Cl org accounted for 46%–77% of total chlorine, with the highest mean ratio in soil layer (0–20 cm). Cl org content exhibited the following trend: F–H layer > L layer > topsoil layer (0–20 cm) > deep soil layer (20–40 cm). The seasonal patterns of Cl org in soil layers were different from that in L and F–H layers, which were mainly controlled by the content and humification degree of organic matter. Cl org storage was much higher in soil layers (61–246 kg/ha) than those in F–H layer (1.1–7.1 kg/ha) and in L layer (0.1–0.8 kg/ha) because of the large thickness of the soil layers. Overall, the Cl org content exhibited an increasing trend with altitude, except at an altitude of approximately 1800 m. Cl org content in L and F–H layers varied more obviously with altitude than that in soil layers. When inorganic chlorine (Cl in ) was not a limiting factor for the chlorination process, Cl org content in L and F–H layers was significantly affected by climate and organic matter controlled by altitude, while Cl org content in soil layers was also mediated by metal ions and pH, and soil particle size. This study could provide a scientific basis for assessing the chlorine cycle in nature.
研究领域:
环境科学
·
土壤学
✓ 已验证
DOI
PubMed
高影响因子
EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY
·
2019
·Vol. 121
·期 7
·1800493
·
IF 1.852
Zi-Xuan Wu,Xiao-Pei Hu,Da-Yong Zhou,Zhi-Feng Tan,Yu-Xin Liu,Hong-Kai Xie,Kanyasiri Rakariyatham,Fereidoon Shahidi
The scallops Chlamys farreri and Patinopecten yessoensis from the Yellow Sea are evaluated according to the seasonal changes of lipid nutritional value including lipid classes, phospholipid (PL) classes, fatty acid (FA) composition, atherogenicity index (IA), thrombogenicity index (IT), and glycerophospholipid molecular species, for the first time. More than 32 species of glycerophosphocholine (GPCho) and 42 species of glycerophosphoethanolamine (GPEtn) are determined. For samples harvested in February, the PL molecular species containing eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) account for 48.57–50.77% and 80.45–85.50% of total molecular species, respectively, for GPCho and GPEtn. Moreover, the samples harvested in February contain higher levels of polyunsaturated fatty acid (PUFA) (58.76–59.12% of total FA) and PL (84.67–85.11% of total lipids) but lower level of cholesterol (8.77–10.10%) as well as IA (0.29–0.31) and IT (0.12–0.13) compared to samples harvested in other seasons. Therefore considering nutritional value, the lipids from scallops ( C. farreri and P. yessoensis ) harvested in February have better value in view of commercial exploitation. Practical Application : A systematic and in-depth investigation on seasonal changes in basic component and lipid nutritional value in adductor muscle of C. farreri and P. yessoensis is reported in this contribution. This useful information makes it possible to use scallop lipid for producing higher value-added products in view of commercial exploitation. Chlamys farreri and Patinopecten yessoensis from the Yellow Sea are evaluated according to the seasonal changes of lipid qualities including lipid classes, phospholipid classes, fatty acid composition, atherogenicity index, thrombogenicity index, and glycerophospholipid molecular species for the first time. Considering nutritional value, the lipids from scallops ( C. farreri and P. yessoensis ) harvest in February have better value in view of commercial exploitation.
研究领域:
水生生物学
·
营养学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2023
·
IF 8.7
Feiyang Xia,Yelin Wang,Dunqiu Wang,Yanpeng Cai,Jun Zhang
Rivers have received extensive attention as a major pathway for microplastics (<5000 μm) from land to ocean. This study investigated the seasonal variation of microplastic contamination in surface water of the Liangfeng River catchment, a tributary of the Li River in China, based on a fluorescence-based protocol, and further explored the migration process of microplastic in the river catchment. The abundance of microplastics (50–5000 μm) was (6.20 ± 0.57)–(41.93 ± 8.13) items/L, of which 57.89–95.12% were small-sized microplastics (<330 μm). The microplastic fluxes in the upper Liangfeng River, lower Liangfeng River, and upper Li River were (14.89 ± 1.24) × 10 12 , (5.71 ± 1.15) × 10 12 , and (1.54 ± 0.55) × 10 14 items/year, respectively. The 3.70% of microplastic load in the mainstream came from the tributary input. Fluvial processes can effectively retain 61.68% of microplastics in the surface water of river catchments, especially for small-sized microplastics. The rainy season is the main period of microplastic retention (91.87%) in the tributary catchment by fluvial processes, while exporting 77.42% of one-year microplastic emissions from the tributary catchment into the mainstream. This study is the first to reveal the transport characteristics of small-sized microplastics in river catchments based on flux variation, which not only can partly explain the “missing small-sized microplastic fraction” in the ocean, but also contribute to improving microplastic model.
研究领域:
环境科学
·
生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Biofuels Bioproducts & Biorefining-Biofpr
·
2021
·Vol. 16
·期 2
·510-522
·
IF 4.102
Qingyun Luo,Zhengfeng Tian,Tiefeng Zheng,Sun Xu,Yuandan Ma,Shuzhen Zou,Zhaojiang Zuo
Cinnamomum camphora (L.) J. Presl can produce an abundance of terpenoids, and has four main chemotypes: linalool, eucalyptol, camphor, and borneol. Antioxidant activity and the chemical composition of extracts from the four chemotypes were investigated during spring (May), summer (July), and autumn (November) with the aim of developing natural antioxidants using suitable chemotypes of C. camphora in suitable seasons, together with their main terpenoids. The main antioxidant terpenoids were identified. The four chemotype extracts showed strong scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3- ethylbenzothiazoline-6-sulphonic acid) (ABTS) free radicals as well as O 2 – · and ·OH in July, due to the fact that their terpenoid content was at its highest during this month. Among the four chemotypes, the strongest scavenging activity was mainly detected in the linalool chemotype extracts, which had the highest terpenoid content. Among the ten main terpenoids in C. camphora extracts, ocimene, linalool, β -pinene, longifolene and eucalyptol showed stronger scavenging activity against DPPH free radicals, and ocimene exhibited the strongest scavenging activity. Extracts from the four chemotypes of C. camphora and their main terpenoids have the potential for development as natural antioxidants, with summer as the best season, linalool chemotypes as the optimum choice, and ocimene as the optimum compound. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd
研究领域:
植物学
·
天然产物化学
·
药理学
✓ 已验证
DOI
高影响因子