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Content and Ecological Risk Assessment of Heavy Metals in Surface Sediment in Weishan Lake 被引量:6
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作者 JIANG Wan-xiang Department of Life Sciences,Zaozhuang University,Zaozhuang 277160,China 《Meteorological and Environmental Research》 CAS 2011年第5期65-67,70,共4页
[Objective] The aim was to analyze the content of heavy metals in surface sediment in Weishan Lake and further assess its ecological risk.[Method] Heavy metal pollution in surface sediment in Weishan Lake was studied,... [Objective] The aim was to analyze the content of heavy metals in surface sediment in Weishan Lake and further assess its ecological risk.[Method] Heavy metal pollution in surface sediment in Weishan Lake was studied,and the pollution indices and potential ecological risk indices of Cu,Zn,Pb,Cd and Cr were calculated to assess the potential ecological risk of heavy metal pollution.[Result] In surface sediment in Weishan Lake,the average contents of Cu,Zn,Pb,Cd,Cr and Ni were 64.78,185.05,78.76,0.17,37.76 and 46.84mg/kg respectively.Cr and Cd weren't beyond standards in all stations,while Cu and Pb exceeded standards in all stations,with average super-standard multiple of 0.85 and 0.31,respectively,and Zn content wasn't beyond standard in S2 station,with average super-standard multiple of 0.24.The average pollution indices of Cu,Zn,Pb,Cd and Cr were 1.85,1.23,1.31,0.34 and 0.47 respectively,with average comprehensive pollution index of 5.21,which showed that heavy metal pollution was light.In addition,heavy metal pollution in entryway portion and sea-route portion were more serious than that of breeding portion.Potential ecological risk assessment showed that the average potential ecological risk indices of Cu,Zn,Pb,Cd and Cr were 9.25,1.23,6.56,10.34 and 0.94 respectively,with average comprehensive potential ecological risk index of 28.33,and it revealed that potential ecological risk of heavy metals was slight.Besides,the potential ecological risk order of heavy metal pollution was sea-route portion>entryway portion>breeding portion.[Conclusion] The study could provide references for the regulation and improvement of ecological environment in Weishan Lake in the east route of south-to-north water transfer project. 展开更多
关键词 Weishan Lake SEDIMENT Heavy metal Potential ecological risk assessment Comprehensive pollution index China
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Ecological Risk Assessment of World Heritage Sites Using RS and GIS:A Case Study of Huangshan Mountain, China 被引量:2
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作者 HUANG Shiman HU Qingwu +1 位作者 WANG Shaohua LI Haidong 《Chinese Geographical Science》 SCIE CSCD 2022年第5期808-823,共16页
Ecological risk assessment(ERA) is an indispensable method for systematic monitoring of World Heritage Sites(WHSs) exposed to various anthropogenic factors and natural disasters. Remote sensing(RS) and geographical in... Ecological risk assessment(ERA) is an indispensable method for systematic monitoring of World Heritage Sites(WHSs) exposed to various anthropogenic factors and natural disasters. Remote sensing(RS) and geographical information systems(GIS) can eliminate many limitations in traditional ERA methods. In this study, changes in ecological risk at Huangshan Mountain, the first mixed WHS in China, over the period of 1984–2019 were explored using remote sensing images and products by considering both natural disasters and human disturbance. Results show that of the four land cover types in Huangshan Mountain, namely water, forest, building and farmland, the main land cover type is forest. During the 35 yr, lands categorised at low or relatively low ecological risk levels are dominant in Huangshan Mountain, with the lowest and highest ERIs(ecological risk index) in 1990 and 2010, respectively. The areas at the five ecological risk levels have declined as follows: relatively low > low > medium > relatively high > high. Changes in ecological risks are closely related to changes in land cover and natural disasters. Even though major natural disasters may affect the ecological risk level in the whole region, changes in land cover caused by human activities will shift the ecological risk level in some areas. Our attempts can be modified and applied to other sites, and offer policy implications for protection and preservation of WHSs. 展开更多
关键词 ecological risk assessment ecological risk index(ERI) world heritage site landscape ecological index Huangshan Mountain Remote Sensing
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Spatial Distribution and Ecological Risk Assessment of Heavy Metals in Surface Sediment of Songhua River,Northeast China 被引量:1
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作者 LIU Baolin DONG Deming +2 位作者 HUA Xiuyi DONG Weihua LI Ming 《Chinese Geographical Science》 SCIE CSCD 2021年第2期223-233,共11页
The Songhua River,one of the seven major rivers in China,locates in Northeast China with 1897 km long.This study aims to investigate the concentrations,distribution,source apportionment and ecological risk assessment ... The Songhua River,one of the seven major rivers in China,locates in Northeast China with 1897 km long.This study aims to investigate the concentrations,distribution,source apportionment and ecological risk assessment of heavy metals including copper(Cu),zinc(Zn),cadmium(Cd),lead(Pb),nickel(Ni)and chromium(Cr)in main stream and tributaries of the Songhua River in Jilin Province,Northeast China.Surface sediment samples(0–15 cm)were collected from 39 sampling sites in the Songhua River in July 2012.Concentrations of Cu,Zn,Cd,Pb,Ni and Cr were analyzed.The mean concentrations of heavy metals were(24.0±9.2)mg/kg,(59.3±18.0)mg/kg,(4.0±2.1)mg/kg,(39.0±27.9)mg/kg,(18.5±8.6)mg/kg and(56.1±17.6)mg/kg for Cu,Zn,Cd,Pb,Cr and Ni,respectively.The average contents of Cu,Cd,Pb,Cr and Ni were higher than their background values.Higher concentrations of heavy metals were found in the lower reaches with industrial enterprises and cities along the Songhua River.Zn,Pb and Ni might come from industrial sewage and mineral processing,while Cu and Cd were derived from electroplating wastewater and agricultural non-point source sewage.Cr originated from lithogenic sources.The concentrations of Cu,Zn and Cr were below the effect range low(ERL)at all sites,while Cd,Pb and Ni concentrations were detected ranging from ERL to the effect range median(ERM)at more than 15%of samples.Concentrations of Ni exceeded ERM in more than 50%of samples.The mean toxic units of heavy metals in the Songhua River decreased following the order:Cd(6.7)>Pb(2.2)>Ni(1.6)>Cu(0.7)>Cr(0.5)=Zn(0.5).Potential ecological risk index was found to be higher in middle and lower reaches of the Songhua River,where Cd could impose an extremely high ecological risk. 展开更多
关键词 heavy metals surface sediment ecological risk assessment Songhua River Northeast China
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Occurrence, partition behavior, source and ecological risk assessment of nitro-PAHs in the sediment and water of Taige Canal, China 被引量:1
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作者 Jijie Kong Tao Ma +7 位作者 Xiaoyu Cao Weidi Li Fengxiao Zhu Huan He Cheng Sun Shaogui Yang Shiyin Li Qiming Xian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第2期782-793,共12页
Nitrated polycyclic aromatic hydrocarbons(NPAHs)are widespread organic pollutants that possess carcinogenic and mutagenic properties,so they may pose a risk to the environment and human health.In this study,the concen... Nitrated polycyclic aromatic hydrocarbons(NPAHs)are widespread organic pollutants that possess carcinogenic and mutagenic properties,so they may pose a risk to the environment and human health.In this study,the concentrations of 15 NPAHs and 16 polycyclic aromatic hydrocarbons(PAHs)in 30 surface water samples and 26 sediment samples were measured in 2018 from the Taige Canal,one of the main rivers flowing into Taihu Lake,China.The total NPAH concentrations in water and sediment ranged from 14.7 to 235 ng/L and 22.9 to 96.5 ng/g dw,respectively.9-nitrophenanthrene(nd–76.3 ng/L)was the dominant compound in surface water,while 2+3-nitrofluoranthene(1.73–18.1 ng/g dw)dominated in sediment.Among PAHs,concentration ranging from 1,097 to 2,981 ng/L and 1,089 to 4,489 ng/g dw in surface water and sediment,respectively.There was a strong positive correlation between the log octanol-water partition coefficient(Kow)and log sediment-water partition coefficient due to hydrophobic interaction.The fugacity fraction value increased with the decrease of log Kow,and chrysene was transferred from water into sediment.The residual NPAHs in surface water and sediment of the Taige Canal have partial correlation.Diesel engine and coal combustion emissions were probably the principal sources of NPAHs in surface water and sediment.The results of ecological risk assessment showed that some NPAHs inwater(e.g,1-nitropyrene and 6-nitrochrysene)and sediment(e.g.,2-nitrobiphenyl,5-nitroacenaphthene,9-nitrophenanthrene and 2+3-nitrofluoranthene)had moderate ecological risks,which should be of concern. 展开更多
关键词 Nitrated polycyclic aromatic hydrocarbons(NPAHs) OCCURRENCE Partition behavior Source apportionment ecological risk assessment
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Distribution and risk assessment of heavy metals in surface sediments of coastal mudflats on Leizhou Peninsula,China 被引量:1
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作者 Tingting Li Lili Jia +2 位作者 Xin Zhu Min Xu Xinchang Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第1期25-34,共10页
Mudflats play a vital role in maintaining the dynamic balance between sea and land.To understand the characteristics,sources,and pollution risks of six heavy metals(As,Cd,Cr,Cu,Hg,and Pb)in the coastal mudflats on the... Mudflats play a vital role in maintaining the dynamic balance between sea and land.To understand the characteristics,sources,and pollution risks of six heavy metals(As,Cd,Cr,Cu,Hg,and Pb)in the coastal mudflats on the Leizhou Peninsula,257 surface sediment samples were studied using mathematical statistics,correlation analysis,and factor analysis.The results show that the overall concentrations of these heavy metals are low although there are several high abnormal points in the local areas.The strong correlation between these heavy metals indicates that the sources of some of the metals are similar,yet their elemental combinations in different cities(counties)varied.According to the calculated enrichment factor(EF),anthropogenic activity-induced heavy metals were determined in order of decreasing influence:As,Cd,Pb,Cr,Cu,and Hg.The low EF values of Hg indicate that it does not present as a contaminant in the study area,while low values of Cr and Cu from the Lianjiang City suggest that these two metals were also attributed to natural sources.The presence of As,Cd,Cr,Cu,and Pb from the remaining cities(counties)should be influenced by anthropogenic activities.The overall potential ecological risk index indicates that the ecological risks posed by the six analyzed heavy metals to the Leizhou Peninsula mudflats,in order of decreasing risk,are Cd,As,Hg,Pb,Cu,and Cr.It is noteworthy that only Cd in Lianjiang City demonstrated substantial ecological risk.Other examined heavy metals in other cities of the study area showed slight ecological risk. 展开更多
关键词 MUDFLAT heavy metal ecological risk assessment source identification Leizhou Peninsula
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Wet and dry deposition fluxes of heavy metals in Pearl River Delta Region(China):Characteristics,ecological risk assessment,and source apportionment 被引量:20
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作者 Lyumeng Ye Minjuan Huang +6 位作者 Buqing Zhong Xuemei Wang Qiulan Tu Haoran Sun Chao Wang Luolin Wu Ming Chang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第8期106-123,共18页
The atmospheric deposition of heavy metals poses serious risks to the ecological system and human health. To advance our knowledge of atmospheric dry/wet heavy metal deposition in the PRD region, monthly fluxes were e... The atmospheric deposition of heavy metals poses serious risks to the ecological system and human health. To advance our knowledge of atmospheric dry/wet heavy metal deposition in the PRD region, monthly fluxes were examined based on soluble/insoluble fractions of five heavy metal elements(Cu, Pb, Cd, Cr and Zn) in samples collected from January 2014 to December 2015 at Guangzhou(urban) and Dinghushan(suburban) sites. The ratios of wet/dry deposition fluxes indicated that heavy metal deposition was governed by wet deposition rather than dry deposition in the PRD region. Affected by the shifting of the Asian monsoon, wet deposition fluxes exhibited significant seasonal variation between summer monsoon seasons(April to September) and winter monsoon seasons(October to February) in this region. Cd was classified as an extremely strong potential ecological risk based on solubility and the Hakanson ecological risk index. Source contributions to wet deposition were calculated by PMF, suggesting that dust, biomass burning, industries,vehicles, long-range transport and marine aerosol sources in Guangzhou, and Zn fertilizers,marine aerosol sources, agriculture, incense burning, biomass burning, vehicles and the ceramics industry in Dinghushan, were the potential sources of heavy metals. 展开更多
关键词 Atmospheric dry/wet deposition Heavy metals ecological risk assessment Sources apportionment The Pearl River Delta region
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Ecological risk assessment of Cd and other heavy metals in soil-rice system in the karst areas with high geochemical background of Guangxi,China 被引量:6
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作者 Qiong YANG Zhongfang YANG +6 位作者 Qizuan ZHANG Xu LIU Xiaoxiong ZHUO Tiansheng WU Lei WANG Xueji WEI Junfeng JI 《Science China Earth Sciences》 SCIE EI CSCD 2021年第7期1126-1139,共14页
Karst areas are widely distributed in China,and the soil derived in these areas is enriched with trace elements and has the typical characteristics of high geochemical background.Therefore,soil ecological risk has gra... Karst areas are widely distributed in China,and the soil derived in these areas is enriched with trace elements and has the typical characteristics of high geochemical background.Therefore,soil ecological risk has gradually attracted extensive attention.In this study,1090 sets of rice grains and paired rhizosphere soils were collected as research objects from the outcropped karst areas of carbonate rocks in Guangxi,and the concentration characteristics and influencing factors of heavy metals,such as Cd and As,in rice grains and the corresponding soils were studied.According to the Chinese Soil Environmental Quality Standard(GB 15618-2018),the proportion of karstic soil samples in Guangxi with heavy metal(As,Cd,Cr,Cu,Hg,Ni,Pb and Zn)concentrations that exceed the standard risk screening values was generally greater than that of surface soils in China or non-karstic soils in Guangxi.Notably,Cd and As were the most prominently enriched heavy metals in soils.According to the Chinese Food Safety Standard(GB 2762-2017),Pb in rice grains from the studied area did not exceed the standard;the exceedance rates of Cr,Hg,and inorganic As were only about 1%;and the exceedance rate of Cd was 12.5%.Soil Cd concentration increased gradually whereas the concentration and exceedance rate of Cd in rice grains decreased gradually with the increase of soil pH.Specifically,the exceedance rate of Cd in rice grains was only 4%when soil pH>6.5.The results indicated that the risk screening values of Cd element in the Chinese Soil Environmental Quality Standard are not satisfactorily applicable to the ecological risk assessment of Cd in karstic soils.Therefore,the recommended threshold values for the safe utilization and risk control of Cd in karstic soils was proposed so as to provide a basis for soil environmental quality hierarchization,pollution risk control and land safety zoning of agricultural land in karst areas in China. 展开更多
关键词 Heavy metals SOIL Rice grain ecological risk assessment Karst area in Guangxi High geochemical background
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Climate Changes and Sustainability
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作者 Kholoud Z. Ghanem 《Open Journal of Ecology》 2024年第1期17-53,共37页
Climate change is the phrase used to describe long-term changes in temperatures and weather patterns. Changes in the atmosphere and their interactions with diverse geologic, chemical, biological, and geographic variab... Climate change is the phrase used to describe long-term changes in temperatures and weather patterns. Changes in the atmosphere and their interactions with diverse geologic, chemical, biological, and geographic variables are the main contributors to this cyclical adjustment of the Earth’s climate. Such changes may be induced purposefully, because of burning fossil fuels, clearing forests, and raising animals, or they may be natural, brought on by significant volcanic eruptions or variations in the sun’s activity. By significantly increasing the amount of greenhouse gases already in the atmosphere, this heightens the greenhouse effect and contributes to global warming. This work includes several additional theoretical and practical explanations of sustainable development. The theoretical work encompasses hundreds of researches that identify requirements for how development routes might satisfy sustainable development (SD) criteria using economic theory, complex systems approach, ecological science, and other techniques. The agreements made by the Parties in various nations across the world will consider a wide range of perspectives about what would be considered undesirable effects on the environment, the climate system, sustainability, economic growth, or food production. 展开更多
关键词 Earth System Ancient Climatic Changes Causes of Climatic Changes ecological risk assessment ECOSYSTEM Abrupt Climate Change of Earth SUSTAINABILITY
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Comprehensive Investigation and Assessment of Nutrient and Heavy Metal Contamination in the Surface Water of Coastal Bohai Sea in China 被引量:2
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作者 LIN Heshan LI Hongjun +3 位作者 YANG Xiaolong XU Zizhou TONG Yindong YU Xingguang 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第4期843-852,共10页
With the rapid development of industrialization and urbanization of coastal regions,eutrophication and metal pollution have caused serious environmental problems in China.To better understand the potential environment... With the rapid development of industrialization and urbanization of coastal regions,eutrophication and metal pollution have caused serious environmental problems in China.To better understand the potential environmental risks associated with nutrients and heavy metals,the surface water was comprehensively investigated in the coastal Bohai Sea.A total of 150 sites were sampled from seven coastal regions,and the concentrations of nutrients(DIN and DIP)and metals(Cd,Pb,Zn,Cu,Cr,As and Hg)in the surface seawater were measured.The results showed that the DIN concentration of about 50%sites exceeded the Grade-I of Seawater Quality Standard of China.Due to high concentrations of DIN,the status of eutrophication was serious in the Bohai Bay and Shuangtaizi Estuary.According to Seawater Quality Standard of China,Pb,Zn,Hg and Cu were the main metal pollutants in the coastal Bohai Sea.There was generally low ecological risk caused by heavy metals,but certain hotspots existed near Shuangtaizi Estuary and Changxingdao Island. 展开更多
关键词 Bohai Sea EUTROPHICATION heavy metal ecological risk assessment species sensitivity distribution
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Ecological Risk Management of Drinking Water Project: The Case Study of Kunming City
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作者 Ji-liang Zheng Jun Hu +1 位作者 Xuan Zhou Ching Yuen Luk 《Frontiers of Engineering Management》 2015年第3期311-319,323,共10页
Following rapid infrastructure development and industrialization, the problems of water pollution and water shortage have become more severe. Whether there is safe drinking water in cities has attracted wide attention... Following rapid infrastructure development and industrialization, the problems of water pollution and water shortage have become more severe. Whether there is safe drinking water in cities has attracted wide attention.The ecological risk management of drinking water project is an important means of ensuring the safety of a drinking water source. Based on ecological risk assessment and management theories, this paper establishes an ecological risk management model and assessment system with the aim of providing theoretical guidance and scientific basis for formulating a policy on the safety and protection of drinking water sources in a city. Kunming is one of the cities plagued by severe water shortage in China. Its ecological risk management of drinking water has attracted the attention of both the local government and the public.Using Kunming as the case study, this paper conducts a comparative analysis and assessment on three major reservoirs that face ecological risks. It highlights the existing problems and gives helpful suggestions. 展开更多
关键词 drinking water project ecological risk ecological risk assessment risk management
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Geostatistical modelling and mapping of nematode-based soil ecological quality indices in a polluted nature reserve 被引量:2
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作者 Israel O.IKOYI Gerard B.M.HEUVELINK Ron G.M.DE GOEDE 《Pedosphere》 SCIE CAS CSCD 2021年第5期670-682,共13页
Nematodes are indicators of soil quality and soil health.Knowledge of the relationships between nematode-based soil quality indices and environmental properties is beneficial for assessing environmental threats on soi... Nematodes are indicators of soil quality and soil health.Knowledge of the relationships between nematode-based soil quality indices and environmental properties is beneficial for assessing environmental threats on soil biota.This study evaluated the spatial distribution of nematode-based soil quality indices in a 23-ha heavy metal-polluted nature reserve using geostatistical methods.We expected that a selection of abiotic soil properties(pH and moisture,clay,organic matter,cadmium(Cd),and zinc(Zn)contents)could explain a significant portion of the spatial variation of the indices and that regression kriging could more accurately model their spatial distribution than ordinary kriging.A stratified simple random sampling scheme was used to select 80 locations where soil samples were taken to extract nematodes and derive the indices.The area had a distinct gradient in soil properties with Cd and Zn content ranging from 0.07 to 68.9 and 5.3 to 1329 mg kg^(-1),respectively.Linear regression models were fitted to describe the relationships between the indices and soil properties.By also modelling the spatial correlation structure of regression residuals using spherical semivariograms,regression kriging was used to produce maps of the indices.The regression models explained between 21% and 44% of the total original variance in the indices.Soil pH was a significant explanatory variable in almost all cases,while heavy metal conent had a remarkably low effect.In some cases,the regression residuals had spatial structure.Independent validation indicated that in all cases,regression kriging performed slightly better because of having lower values of the root mean square prediction error and a mean prediction error closer to zero than ordinary kriging.This study showed the importance of soil properties in explaining the spatial distribution of biological soil quality indices in ecological risk assessment. 展开更多
关键词 ecological risk assessment heavy metals model validation regression kriging semivariance analysis soil property spatial structure
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Ecology of industrial pollution in China 被引量:3
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作者 Jingjing Yuan Yonglong Lu +9 位作者 Chenchen Wang Xianghui Cao Chunci Chen Haotian Cui Meng Zhang Cong Wang Xiaoqian Li Andrew C.Johnson Andrew J.Sweetman Di Du 《Ecosystem Health and Sustainability》 SCIE 2020年第1期152-168,151,共18页
Industrial development has brought China both opportunities and challenges since the reform and opening up in 1978.Spatial and temporal analysis showed that rapid industrialization has made eastern China under a more ... Industrial development has brought China both opportunities and challenges since the reform and opening up in 1978.Spatial and temporal analysis showed that rapid industrialization has made eastern China under a more serious pollution stress.The most serious effects of industrial pollution were reflected in aquatic and soil ecosystem degradation,and damage can be observed from species,population,and community to ecosystem level.Public consciousness about contaminated sites rose from 2004 leading to greater efforts in ecological remediation,monitoring,and risk governance.Considerable efforts are still needed in expanding the extent and breadth of monitoring to explore where the greatest ecological risks lie and how to control them.Ecology of industrial pollution has become a popular discipline in China and will be further developed to help achieve the Sustainable Development Goals.Future research for a better ecological risk management should be focused on multi-media transfer and effects of mixed pollutants,mechanisms for clean energy and material flow,and integration of ecological risk with human health risk. 展开更多
关键词 Industrial pollution soil and aquatic ecosystem watershed monitoring and assessment contaminated site ecological risk assessment ecosystem management
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Nutrient status and pollution levels in five areas around a manganese mine in southern China 被引量:1
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作者 Kehui Liu Xiaolu Liang +2 位作者 Chunming Li Fangming Yu Yi Li 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2020年第6期97-107,共11页
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
关键词 ecological reclamation ecological risk assessment Heavy metal Mn mine Soil nutrients
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