The Loess Plateau region in China is characterized by a fragile environment,where vegetation is susceptible to both natural variations and anthropogenic influences.Previous research has indicated a greening trend in v...The Loess Plateau region in China is characterized by a fragile environment,where vegetation is susceptible to both natural variations and anthropogenic influences.Previous research has indicated a greening trend in vegetation across the Loess Plateau over the past two decades.However,the specific contributions of natural and anthropogenic drivers,both individually and interactively,to vegetation distribution remain unclear.To address this gap,we conducted a study using Shaanxi Province as a case area.Utilizing multisource data,we employed the Geographical Detector Model(GDM)to analyze the impacts of natural and human related factors on vegetation distribution.Our analysis revealed that the average NDVI(Normalized Difference Vegetation Index)increased at a rate of 0.006 per year from 2000 to 2021.Notably,88.8%of the region experienced vegetation greening,while 4.5%showed significant declines in NDVI,particularly in areas,such as Xi'an,Weinan,Baoji,Hanzhong,and Ankang.Furthermore,NDVI trend projections suggest that the area undergoing vegetation degradation may surpass the area showing improvement in the future.The study identified that vegetation distribution was influenced by both natural and anthropogenic factors for the whole study area.Precipitation,surface types and land use type were the primary factors with q values above 0.5.During the study period,impacts of GDP,nighttime lights and population density among anthropogenic factors on vegetation distribution increased by 130%,125%and 41%,respectively.Conversely,except for slope and aspect,natural factors'influence on vegetation distribution declined by 5%to 26%.The impact of driving factors on NDVI distribution varied across ecological regions.In Fenwei Basin Agro-Ecoregion(EcoregionⅢ),the influence of anthropogenic factors on vegetation distribution was greater than that in the other three ecoregions.Precipitation primarily affected the vegetation distribution in Loess Plateau Agricultural and Grassland Ecoregion(EcoregionⅡ).Additionally,the combined interactive effects of factors had a stronger influence on NDVI distribution than any single factor.These findings provide valuable insights for local governments in Shaanxi Province to develop targeted ecological restoration and environmental management policies.展开更多
Objective:Heavy metal and harmful element contamination are frequently reported in Chinese herbal medicines(CHMs),and roots and rhizomes parts showed a higher content than other parts.To investigate the residue level ...Objective:Heavy metal and harmful element contamination are frequently reported in Chinese herbal medicines(CHMs),and roots and rhizomes parts showed a higher content than other parts.To investigate the residue level and assess the potential human health risk of heavy metals and harmful elements in roots and rhizomes,720 batches of the sample representing 20 species of herbs from different sources were collected.Methods:The content of Pb,Cd,As,Hg,and Cu in the digests was determined using ICP-MS.The chronic hazard index estimate based on non-cancer hazard quotient(HQ)was applied for potential health risk assessment of Pb,Cd,As,Hg,and Cu via consumption of CHMs.Results:Compared with the Chinese limit standard(Chinese Pharmacopoeia Commission,2020 edition)of Pb,Cd,As,Hg,and Cu in Ginseng Radix et Rhizoma,the exceedance percentage of Pb in total samples was 14.1%,which were generally far higher than Cd,As,Hg,and Cu.Health risk assessment results based on hazard quotient calculating showed that total HQ of Cu,Pb,As,Cd,and Hg in Pulsatillae Radix and Clematidis Radix et Rhizoma exceeded 1,with the value of 1.543 and 1.235.Besides,Arsenic had the highest HQ value(0.957)in Pulsatillae Radix.Conclusion:Consuming raw materials of Pulsatillae Radix and Clematidis Radix et Rhizoma may pose a potential risk and Arsenic residues in Pulsatillae Radix deserved special attention.展开更多
Objective: Angelicae Sinensis Radix(ASR, Danggui in Chinese), Cistanches Herba(CH, Roucongrong in Chinese), Ginseng Radix et Rhizoma(PG, Renshen in Chinese), and Panacis Quinquefolii Radix(PQ,Xiyangshen in Chinese), w...Objective: Angelicae Sinensis Radix(ASR, Danggui in Chinese), Cistanches Herba(CH, Roucongrong in Chinese), Ginseng Radix et Rhizoma(PG, Renshen in Chinese), and Panacis Quinquefolii Radix(PQ,Xiyangshen in Chinese), widely used as medicine and dietary supplement around the world, are susceptible to fungal and mycotoxin contamination. In this study, we aim to analyze their fungal community by DNA metabarcoding.Methods: A total of 12 root samples were collected from three main production areas in China. The samples were divided into four groups based on herb species, including ASR, CH, PG, and PQ groups. The fungal community on the surface of four root groups was investigated through DNA metabarcoding via targeting the internal transcribed spacer 2 region(ITS2).Results: All the 12 samples were detected with fungal contamination. Rhizopus(13.04%-74.03%),Aspergillus(1.76%-23.92%), and Fusarium(0.26%-15.27%) were the predominant genera. Ten important fungi were identified at the species level, including two potential toxigenic fungi(Penicillium citrinum and P. oxalicum) and eight human pathogenic fungi(Alternaria infectoria, Candida sake, Hyphopichia burtonii, Malassezia globosa, M. restricta, Rhizopus arrhizus, Rhodotorula mucilaginosa, and Ochroconis tshawytschae). Fungal community in ASR and CH groups was significantly different from other groups,while fungal community in PG and PQ groups was relatively similar.Conclusion: DNA metabarcoding revealed the fungal community in four important root herbs. This study provided an important reference for preventing root herbs against fungal and mycotoxin contamination.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF0801304)Philosophy and Social Science Foundation of China(Grant No.23BRK011,24CTJ021)+3 种基金the Humanities and Social Sciences Research Planning Fund of the Ministry of Education,China(Grant No.22YJAZH020)Shaanxi Provincial Social Science Foundation(Grant No.2024D041)Graduate Innovation Funds of Xi’an University of Finance and Economics(Grant No.23YC011)the Youth Innovation Team of Shaanxi Universities,China。
文摘The Loess Plateau region in China is characterized by a fragile environment,where vegetation is susceptible to both natural variations and anthropogenic influences.Previous research has indicated a greening trend in vegetation across the Loess Plateau over the past two decades.However,the specific contributions of natural and anthropogenic drivers,both individually and interactively,to vegetation distribution remain unclear.To address this gap,we conducted a study using Shaanxi Province as a case area.Utilizing multisource data,we employed the Geographical Detector Model(GDM)to analyze the impacts of natural and human related factors on vegetation distribution.Our analysis revealed that the average NDVI(Normalized Difference Vegetation Index)increased at a rate of 0.006 per year from 2000 to 2021.Notably,88.8%of the region experienced vegetation greening,while 4.5%showed significant declines in NDVI,particularly in areas,such as Xi'an,Weinan,Baoji,Hanzhong,and Ankang.Furthermore,NDVI trend projections suggest that the area undergoing vegetation degradation may surpass the area showing improvement in the future.The study identified that vegetation distribution was influenced by both natural and anthropogenic factors for the whole study area.Precipitation,surface types and land use type were the primary factors with q values above 0.5.During the study period,impacts of GDP,nighttime lights and population density among anthropogenic factors on vegetation distribution increased by 130%,125%and 41%,respectively.Conversely,except for slope and aspect,natural factors'influence on vegetation distribution declined by 5%to 26%.The impact of driving factors on NDVI distribution varied across ecological regions.In Fenwei Basin Agro-Ecoregion(EcoregionⅢ),the influence of anthropogenic factors on vegetation distribution was greater than that in the other three ecoregions.Precipitation primarily affected the vegetation distribution in Loess Plateau Agricultural and Grassland Ecoregion(EcoregionⅡ).Additionally,the combined interactive effects of factors had a stronger influence on NDVI distribution than any single factor.These findings provide valuable insights for local governments in Shaanxi Province to develop targeted ecological restoration and environmental management policies.
基金funded by the National Key R&D Program of China(No.2018YFC1602102)。
文摘Objective:Heavy metal and harmful element contamination are frequently reported in Chinese herbal medicines(CHMs),and roots and rhizomes parts showed a higher content than other parts.To investigate the residue level and assess the potential human health risk of heavy metals and harmful elements in roots and rhizomes,720 batches of the sample representing 20 species of herbs from different sources were collected.Methods:The content of Pb,Cd,As,Hg,and Cu in the digests was determined using ICP-MS.The chronic hazard index estimate based on non-cancer hazard quotient(HQ)was applied for potential health risk assessment of Pb,Cd,As,Hg,and Cu via consumption of CHMs.Results:Compared with the Chinese limit standard(Chinese Pharmacopoeia Commission,2020 edition)of Pb,Cd,As,Hg,and Cu in Ginseng Radix et Rhizoma,the exceedance percentage of Pb in total samples was 14.1%,which were generally far higher than Cd,As,Hg,and Cu.Health risk assessment results based on hazard quotient calculating showed that total HQ of Cu,Pb,As,Cd,and Hg in Pulsatillae Radix and Clematidis Radix et Rhizoma exceeded 1,with the value of 1.543 and 1.235.Besides,Arsenic had the highest HQ value(0.957)in Pulsatillae Radix.Conclusion:Consuming raw materials of Pulsatillae Radix and Clematidis Radix et Rhizoma may pose a potential risk and Arsenic residues in Pulsatillae Radix deserved special attention.
基金supported by CAMS Innovation Fund for Medical Sciences(CIFMS)(No.2021-I2M-1-071).
文摘Objective: Angelicae Sinensis Radix(ASR, Danggui in Chinese), Cistanches Herba(CH, Roucongrong in Chinese), Ginseng Radix et Rhizoma(PG, Renshen in Chinese), and Panacis Quinquefolii Radix(PQ,Xiyangshen in Chinese), widely used as medicine and dietary supplement around the world, are susceptible to fungal and mycotoxin contamination. In this study, we aim to analyze their fungal community by DNA metabarcoding.Methods: A total of 12 root samples were collected from three main production areas in China. The samples were divided into four groups based on herb species, including ASR, CH, PG, and PQ groups. The fungal community on the surface of four root groups was investigated through DNA metabarcoding via targeting the internal transcribed spacer 2 region(ITS2).Results: All the 12 samples were detected with fungal contamination. Rhizopus(13.04%-74.03%),Aspergillus(1.76%-23.92%), and Fusarium(0.26%-15.27%) were the predominant genera. Ten important fungi were identified at the species level, including two potential toxigenic fungi(Penicillium citrinum and P. oxalicum) and eight human pathogenic fungi(Alternaria infectoria, Candida sake, Hyphopichia burtonii, Malassezia globosa, M. restricta, Rhizopus arrhizus, Rhodotorula mucilaginosa, and Ochroconis tshawytschae). Fungal community in ASR and CH groups was significantly different from other groups,while fungal community in PG and PQ groups was relatively similar.Conclusion: DNA metabarcoding revealed the fungal community in four important root herbs. This study provided an important reference for preventing root herbs against fungal and mycotoxin contamination.
