In total,9,552 documents were extracted from the Web of Science Core Collection and subjected to knowledge mapping and visualization analysis for the field of phytoremediation of HM-contaminated soil(PHMCS)with CiteSp...In total,9,552 documents were extracted from the Web of Science Core Collection and subjected to knowledge mapping and visualization analysis for the field of phytoremediation of HM-contaminated soil(PHMCS)with CiteSpace 5.7 R3 software.The results showed that(1)the number of publications increased linearly over the studied period.The top 10 countries/regions,institutions and authors contributing to this field were exhibited.(2)Keyword co-occurrence cluster analysis revealed a total of 8 clusters,including“Bioremediation,”“Arsenic,”“Biochar,”“Oxidative stress,”“Hyperaccumulation,”“EDTA,”“Arbuscular mycorrhizal fungi,”and“Environmental pollution”clusters(3)In total,334 keyword bursts were obtained,and the 25 strongest,longest duration,and newest keyboard bursts were analyzed in depth.The strongest keyword burst test showed that the hottest keywords could be divided into 7 groups,i.e.,“Plant bioremediation materials,”“HM types,”“Chelating amendments,”“Other improved strategies,”“Bioremediation characteristics,”“Risk assessment,”and“Other.”Almost half of the newest topics had emerged in the past 3 years,including“biochar,”“drought,”“health risk assessment,”“electrokinetic remediation,”“nanoparticle,”and“intercropping.”(4)In total,9 knowledge base clusters were obtained in this study.The studies of Ali et al.(2013),Blaylock et al.(1997),Huang et al.(1997),van der Ent et al.(2013),Salt et al.(1995),and Salt(1998),which had both high frequencies and the strongest burst scores,have had the most profound effects on PHMCS research.Finally,future research directions were proposed.展开更多
Nutrient status and pollution levels are the main factors affecting soil restoration.The nutrient status and pollution levels in five areas,an unexplored mine area(UA),an explored mine area(EA),a tailings area(TA),a r...Nutrient status and pollution levels are the main factors affecting soil restoration.The nutrient status and pollution levels in five areas,an unexplored mine area(UA),an explored mine area(EA),a tailings area(TA),a reclamation area(RA)and an agricultural area(AA),around the Pingle manganese mine in Guangxi,China,were assessed in this study.The results showed that the average total phosphorus in these five areas ranged from 1.05 to 1.57 mg/kg,corresponding to grades of extremely high and high.The average total nitrogen values were 0.19,0.69,0.93,1.24 and 1.67 mg/kg in EA,TA,RA,UA and AA,corresponding to grades of very low,low,medium-low,medium-high and medium-high,respectively.The average organic matter values were 12.78,8.92,22.77,21.29 and 29.11 mg/kg in EA,TA,RA,UA and AA,which corresponded to grades of medium-low,low,medium-high,medium-high and medium-high,respectively.All these results indicated that the total phosphorus was sufficient in these areas,while the total nitrogen and organic matter were insufficient in EA,TA and RA.The available concentrations of Mn and Zn corresponded to the intermediate grade,while the values for Cu corresponded to the very low grade;these might be another factor restricting ecological reclamation.Contamination and ecological risk assessments based on the single contamination index,Nemerow multi-factor index and potential ecological risk index showed that the five tested areas around the Mn mine were considered heavily polluted and presented high ecological risk.Mn and Cd were the dominant pollutants.展开更多
The current study evaluated the effects of oxalic acid(OA)application on the growth and Mn phytoremediation efficiency of Polygonum pubescens Blume cultivated in three different manganese(Mn)-contaminated soils sample...The current study evaluated the effects of oxalic acid(OA)application on the growth and Mn phytoremediation efficiency of Polygonum pubescens Blume cultivated in three different manganese(Mn)-contaminated soils sampled from an unexplored area(US),an explored area(ES)and a tailing area(TS)of the Ertang Mn mine,South China.The supplied levels of OA were 0(control),1(low level),3(medium level),and 9(high level)mmol/kg,referred to as CK,OA1,OA3 and OA9,respectively.The results revealed that the average water-extractable Mn concentrations US,ES and TS amended with OA increased by 214.13,363.77 and 266.85%,respectively.All OA supply levels increased plant growth and Mn concentrations in US.The low OA supply level increased plant growth in ES and TS;however,contrasting results were found for the medium and high OA supply levels.Plant Mn concentrations and total Mn increased in ES and TS in response to all OA supply levels.Total Mn in the aerial parts increased by 81.18,44.17 and 83.17%in US,ES and TS,respectively;the corresponding percentages for the whole plants were 81.53,108.98 and 77.91%,respectively.The rate of·O_(2)^(−)production and malondialdehyde(MDA)concentrations increased in response to OA amendment,especially the medium and high OA supply levels in ES and TS.In general,antioxidant enzymes might play a vital role in alleviating Mn stress in plants cultivated in US,while non-enzymatic antioxidants might be the main factor for plants cultivated in ES and TS.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.41967019)the National Social Science Foundation Project of China(No.16BTQ033).
文摘In total,9,552 documents were extracted from the Web of Science Core Collection and subjected to knowledge mapping and visualization analysis for the field of phytoremediation of HM-contaminated soil(PHMCS)with CiteSpace 5.7 R3 software.The results showed that(1)the number of publications increased linearly over the studied period.The top 10 countries/regions,institutions and authors contributing to this field were exhibited.(2)Keyword co-occurrence cluster analysis revealed a total of 8 clusters,including“Bioremediation,”“Arsenic,”“Biochar,”“Oxidative stress,”“Hyperaccumulation,”“EDTA,”“Arbuscular mycorrhizal fungi,”and“Environmental pollution”clusters(3)In total,334 keyword bursts were obtained,and the 25 strongest,longest duration,and newest keyboard bursts were analyzed in depth.The strongest keyword burst test showed that the hottest keywords could be divided into 7 groups,i.e.,“Plant bioremediation materials,”“HM types,”“Chelating amendments,”“Other improved strategies,”“Bioremediation characteristics,”“Risk assessment,”and“Other.”Almost half of the newest topics had emerged in the past 3 years,including“biochar,”“drought,”“health risk assessment,”“electrokinetic remediation,”“nanoparticle,”and“intercropping.”(4)In total,9 knowledge base clusters were obtained in this study.The studies of Ali et al.(2013),Blaylock et al.(1997),Huang et al.(1997),van der Ent et al.(2013),Salt et al.(1995),and Salt(1998),which had both high frequencies and the strongest burst scores,have had the most profound effects on PHMCS research.Finally,future research directions were proposed.
基金This project was supported by the Key Technologies Research and Development Program of China(No.2017YFD0801500)National Natural Science Foundation of China(Grant Nos.41661077 and 41967019)+2 种基金Guangxi Science and Technology Development Project of Major Projects of Guangxi(Guike AA17204047-3)Guangxi Natural Science Foundation(No.2018JJA150018)We thank American Journal Experts(AJE)for editing the manuscript.
文摘Nutrient status and pollution levels are the main factors affecting soil restoration.The nutrient status and pollution levels in five areas,an unexplored mine area(UA),an explored mine area(EA),a tailings area(TA),a reclamation area(RA)and an agricultural area(AA),around the Pingle manganese mine in Guangxi,China,were assessed in this study.The results showed that the average total phosphorus in these five areas ranged from 1.05 to 1.57 mg/kg,corresponding to grades of extremely high and high.The average total nitrogen values were 0.19,0.69,0.93,1.24 and 1.67 mg/kg in EA,TA,RA,UA and AA,corresponding to grades of very low,low,medium-low,medium-high and medium-high,respectively.The average organic matter values were 12.78,8.92,22.77,21.29 and 29.11 mg/kg in EA,TA,RA,UA and AA,which corresponded to grades of medium-low,low,medium-high,medium-high and medium-high,respectively.All these results indicated that the total phosphorus was sufficient in these areas,while the total nitrogen and organic matter were insufficient in EA,TA and RA.The available concentrations of Mn and Zn corresponded to the intermediate grade,while the values for Cu corresponded to the very low grade;these might be another factor restricting ecological reclamation.Contamination and ecological risk assessments based on the single contamination index,Nemerow multi-factor index and potential ecological risk index showed that the five tested areas around the Mn mine were considered heavily polluted and presented high ecological risk.Mn and Cd were the dominant pollutants.
基金National Natural Science Foundation of China(Nos.41967019 and 41661077)the National Key Technologies Research and Development Program of China(No.2017YFD0801500)+1 种基金the Guangxi Science and Technology Development Project of Major Projects of Guangxi(Guike AA17204047-3)Scientific Research and Technology Development Program of Guilin(Nos.20190205 and 20180107-3).
文摘The current study evaluated the effects of oxalic acid(OA)application on the growth and Mn phytoremediation efficiency of Polygonum pubescens Blume cultivated in three different manganese(Mn)-contaminated soils sampled from an unexplored area(US),an explored area(ES)and a tailing area(TS)of the Ertang Mn mine,South China.The supplied levels of OA were 0(control),1(low level),3(medium level),and 9(high level)mmol/kg,referred to as CK,OA1,OA3 and OA9,respectively.The results revealed that the average water-extractable Mn concentrations US,ES and TS amended with OA increased by 214.13,363.77 and 266.85%,respectively.All OA supply levels increased plant growth and Mn concentrations in US.The low OA supply level increased plant growth in ES and TS;however,contrasting results were found for the medium and high OA supply levels.Plant Mn concentrations and total Mn increased in ES and TS in response to all OA supply levels.Total Mn in the aerial parts increased by 81.18,44.17 and 83.17%in US,ES and TS,respectively;the corresponding percentages for the whole plants were 81.53,108.98 and 77.91%,respectively.The rate of·O_(2)^(−)production and malondialdehyde(MDA)concentrations increased in response to OA amendment,especially the medium and high OA supply levels in ES and TS.In general,antioxidant enzymes might play a vital role in alleviating Mn stress in plants cultivated in US,while non-enzymatic antioxidants might be the main factor for plants cultivated in ES and TS.
