Diversity indices and abundance distribution models are statistical tools which ecologists have applied for decades for analyzing the intrinsic regularities of various ecological entities. In ...Diversity indices and abundance distribution models are statistical tools which ecologists have applied for decades for analyzing the intrinsic regularities of various ecological entities. In this work, we have applied these techniques to use the notions such as pedodiversity (as an example of geodiversity in a broad sense), in order to detect the differences and similarities between both natural resources, biological and non-biological. The discussion has mainly been conducted through the study of landform based pedodiversity analysis applied to SOTER digital databases in Hainan Island, China. The main analytical methods include indices of richness S that are the number of the categories (SOTER units relating to different soils in this work), indices based on proportional abundance of categories H' and E which are not only the number but also their relative abundance (in our case, the relative area occupied by each pedotaxa) is taken into account, models of the distribution of abundance of categories that provide the most complete description but also the least abridged and GIS mapping to show the spatial variation digitally.展开更多
Seventy-eight marine fungal strains were isolated from sediment samples collected off the coast of Nanji Island, Wenzhou, Zhejiang Province, China. Antibacterial screening using the agar disc method showed that 19 of ...Seventy-eight marine fungal strains were isolated from sediment samples collected off the coast of Nanji Island, Wenzhou, Zhejiang Province, China. Antibacterial screening using the agar disc method showed that 19 of the isolated strains could inhibit at least one pathogenic Vibrio from Pseudosciaena crocea. Subsequent screening confirmed that nine strains produced antibacterial metabolites that had activity against one or several types of pathogenic Vibrio. Strain NJ0104 had the widest antimicrobial spectrum and strong activity, particularly against Fibrio parahaemolyticus-MM0810072. A preliminary study of N J0104 antibacterial metabolites demonstrated that they had thermal stability up to 80℃, ultraviolet stability up to 40 min and pH stability between 4.0-7.0. In addition, the antibacterial metabolites were readily soluble in butanol. To identify the specific strain, the ITS-5.8S rDNA regions of NJ0104 were PCR amplified and sequenced. Based on the combination of phenotypic and genotypic data, the strain was identified as Arthrinium sp.展开更多
Redetedrination of the metamorphic age of the gsrnet-bearing mafic wholeulite from the Sstrene Island, Esat Antarctica has been made and an isochron of wholerock-garnet-pyroxene-plagioclase is obtained, giving an age...Redetedrination of the metamorphic age of the gsrnet-bearing mafic wholeulite from the Sstrene Island, Esat Antarctica has been made and an isochron of wholerock-garnet-pyroxene-plagioclase is obtained, giving an age of [604±28(2σ)] Ma. Itis pointed out that this age represents the time of peak granulite facies metamorphism ofthe area. As to the geological relation of the Sstrene Island with the Bolingen Islandsand the Larsemann Hills to the east, it is deduced from the rock assemblages, metamorphic superposition, spatial changes and metamorphic ages between the above regions that the degree of the superposition of the later low pressure metamorphism is becoming stronger from west to east. While the evolution of the earlier medium pressure to later low pressure implies probably the substages of the same metamorphic cycle.展开更多
We quantified microhabitat use by white-footed mice Peromyscus leucopus in forest and old-field habitats occupied by Morrow' s honeysuckle Lonicera morrowii, an invasive exotic shrub imported from Japan. Microhabitat...We quantified microhabitat use by white-footed mice Peromyscus leucopus in forest and old-field habitats occupied by Morrow' s honeysuckle Lonicera morrowii, an invasive exotic shrub imported from Japan. Microhabitat characteristics were compared between trails used by mice ( n = 124) and randomly selected trails ( n = 127) in 4 study plots located at Fort Necessity National Battlefield, Farmington, Pennsylvania, USA. We compared 10 mierohabitat variables between used and random trails using non-metric multidimensional scaling (NMDS) and classification and regression tree (CART) analysis. Trails used by mice were statistically different from randomly selected trails in both forested plots ( P 〈 0. 008) and old-field plots ( P 〈 0. 001 ). In the forested plots, trails of white-footed mice were more often associated with a greater percent cover (% cover) of coarse woody debris (CWD) than were randomly selected trails. In the old-field plots, mouse trails were commonly characterized by having a lower % cover of exotic herbaceous vegetation, a greater % cover of shrubs, and a greater % cover of Morrow' s honeysuckle than randomly selected trails. Our study indicates that white-footed mice do not move randomly and prefer areas of high structural complexity, thereby showing significant microhabitat preference. The preference of white-footed mice for areas with a relatively high percent cover of Morrow's honeysuckle could 1 ) be a factor in the aggressive nature of the exotic honeysuckle shrub's spread throughout the Battlefield or 2) cause the shrub to spread even faster into adjacent areas not yet occupied by Morrow' s honeysuckle展开更多
The diversity,community composition and 16 S rRNA gene abundance of bacterioplankton along a transect across an upwelling area off the eastern coast of Hainan Island(the Qiongdong upwelling)were investigated in August...The diversity,community composition and 16 S rRNA gene abundance of bacterioplankton along a transect across an upwelling area off the eastern coast of Hainan Island(the Qiongdong upwelling)were investigated in August of 2016 using high throughput sequencing and quantitative PCR assay of 16 S rRNA genes.Compared with the offshore stations,the inner-shelf stations had higher bacterial gene abundance(up to 3 fold)and operational taxonomic unit richness,a result of the influence of upwelled and fresher waters.Overall,a majority of the reads were affiliated with Gammaproteobacteria(11%-74%)and Alphaproteobacteria(14%-43%).The structure of the bacterial community was significantly affected by salinity,dissolved oxygen,NO_(3)^(-) and NH_(4)^(+),which also defined the physicochemical features of the upwelled waters.Horizontally,the relative abundances and gene abundances of Rhodobacteraceae,SAR86,Cyanobacteria and Bacteroidetes in eutrophic zone decreased from the inner to outer shelves and slope,whereas Alteromonas,Vibrio and Oceanospirillaceae exhibited an opposite trend.This study stresses the riverine influence on the oceanographic condition and spatial variability of bacterioplankton diversity and distribution in the Qiongdong upwelling.展开更多
Exotic bush honeysuckles (</span><i><span style="font-family:Verdana;">Lonicera</span></i><span style="font-family:Verdana;"> spp.) are becoming increasingly com...Exotic bush honeysuckles (</span><i><span style="font-family:Verdana;">Lonicera</span></i><span style="font-family:Verdana;"> spp.) are becoming increasingly common in the eastern and mid-western United States, but little is known about their impacts on invertebrates. We used a modified leaf vacuum to sample invertebrates in the shrub strata and understory of three shrub types (and open plots </span><span><span style="font-family:Verdana;">in the understory): single Morrow’s honeysuckle (</span><i><span style="font-family:Verdana;">L</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">morrowii</span></i><span style="font-family:Verdana;"> A. Gray) shrubs, </span></span><span style="font-family:Verdana;">single native southern arrowwood (</span><i><span style="font-family:Verdana;">Viburnum</span></i></span></span><span><span><i><span style="font-family:""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">recognitum</span></i></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> Fernald) shrubs, and dense thickets of Morrow’s honeysuckle, in southwestern PA, USA during 2004 and 2005. We also assessed the degree of </span><a name="OLE_LINK26"></a><a name="OLE_LINK25"></a><span style="font-family:Verdana;">herbivory</span><span style="font-family:Verdana;"> on the two species of shrubs. Within the shrub strata, invertebrate biomass was lower in southern arrowwood shrubs, but there was no difference in invertebrate abundance or family richness. Invertebrate abundance and richness were lowest </span><span style="font-family:Verdana;">in August, but there was no difference in biomass among the months. Invertebrate</span><span style="font-family:Verdana;"> abundance, biomass, and family richness were lowest in the understory below dense thickets of Morrow’s honeysuckle. Overall, the percent cover of herbs was the proximate factor responsible for driving patterns of invertebrate abundance, though ultimately these patterns were being driven by shrub type. Abundance and biomass of larval leaf chewers were highest in the native shrub;Morrow’s honeysuckle had a mean of 29.7 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area consumed per 1 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area, while the native shrub had a mean of 284.3 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area consumed. Our results suggest that areas dominated by the exotic shrub negatively impact invertebrate biomass, which may in turn affect organisms at higher trophic levels.展开更多
针对传统被动式检测方法存在较大检测盲区(Non-detection Zone,NDZ)、阈值难以确定以及易受电能质量扰动影响的缺陷,研究了一种基于奇异值分解(Singular Value Decomposition,SVD)和神经网络的被动式孤岛检测方法。该方法首先对公共连接...针对传统被动式检测方法存在较大检测盲区(Non-detection Zone,NDZ)、阈值难以确定以及易受电能质量扰动影响的缺陷,研究了一种基于奇异值分解(Singular Value Decomposition,SVD)和神经网络的被动式孤岛检测方法。该方法首先对公共连接点(Point of Common Coupling,PCC)处电压和逆变器输出电流进行S变换,提取相应的谐波幅值后,对其进行SVD并构成特征向量,最后运用BP神经网络对孤岛以及非孤岛情况进行分类识别。仿真结果表明,该方法可以有效检测出功率平衡情况下发生的孤岛,而且能防止电能质量扰动对检测准确性的影响,具有很高的准确性、可靠性和实用性。展开更多
AIM: To explore the association of methylation of the CpG island in the promotor of the p16 tumor suppressor gene with the clinicopathological characteristics of the colorectal cancers. METHODS: Methylation-specific P...AIM: To explore the association of methylation of the CpG island in the promotor of the p16 tumor suppressor gene with the clinicopathological characteristics of the colorectal cancers. METHODS: Methylation-specific PCR (MSP) was used to detect p16 methylation of 62 sporadic colorectal cancer specimens. RESULTS: p16 methylation was detected in 42% of the tumors.Dukes'staging was associated with p16 methylation status.p16 methylation occurred more frequently in Dukes'C and D patients (75.9%) than in Dukes'A and B patients (12.1%). CONCLUSION: p16 methylation plays a role in the carcinogenesis of a subset of colorectal cancer, and it might be linked to poor prognosis.展开更多
The urban heat island(UHI) effect has significant effects on the quality of life and public health. Numerous studies have addressed the relationship between UHI and the increase in urban impervious surface area(ISA), ...The urban heat island(UHI) effect has significant effects on the quality of life and public health. Numerous studies have addressed the relationship between UHI and the increase in urban impervious surface area(ISA), but few of them have considered the impact of the spatial configuration of ISA on UHI. Land surface temperature(LST) may be affected not only by urban land cover, but also by neighboring land cover. The aim of this research was to investigate the effects of the abundance and spatial association of ISAs on LST. Taking Harbin City, China as an example, the impact of ISA spatial association on LST measurements was examined. The abundance of ISAs and the LST measurements were derived from Landsat Thematic Mapper(TM) imagery of 2000 and 2010, and the spatial association patterns of ISAs were calculated using the local Moran’s I index. The impacts of ISA abundance and spatial association on LST were examined using correlation analysis. The results suggested that LST has significant positive associations with both ISA abundance and the Moran’s I index of ISAs, indicating that both the abundance and spatial clustering of ISAs contribute to elevated values of LST. It was also found that LST is positively associated with clustering of high-ISA-percentage areas(i.e.,>50%) and negatively associated with clustering of low-ISA-percentage areas(i.e.,<25%). The results suggest that, in addition to the abundance of ISAs,their spatial association has a significant effect on UHIs.展开更多
The Tongyu copper deposit, located in the western part of the North Qinling Orogen, China, is one of several volcanic-hosted massive sulphide(VHMS) deposits with industrial value and is also a typical example of min...The Tongyu copper deposit, located in the western part of the North Qinling Orogen, China, is one of several volcanic-hosted massive sulphide(VHMS) deposits with industrial value and is also a typical example of mineralization related to the subduction and metallogenesis during the Caledonian orogeny. We conducted systematic lead-sulphur isotope geochemical analyses of the Tongyu deposit to understand the possible ore-forming material sources and tectonic settings. Twenty-six sulphide samples yielded clustered δ^34SCDT values of 1.13‰-3.36‰, average 2.22‰, and show a tower-type distribution,implying that the sulphur of the Tongyu copper deposit mainly originated from a mantle source. The Pb isotope compositions of sulphides(^206Pb/^204Pb = 17.59225-18.56354, average 18.32020; ^207Pb/^204Pb =15.51770-15.69381, average 15.66217; ^208Pb/^204Pb= 37.99969-39.06953, average 38.52722) are close to the values of the volcanic host rocks(^206Pb/^204PbPb= 18.10678-18.26293, average 18.21158; ^207Pb/^204PbPb =15.63196-15.68188, average 15.65345; ^208Pb/^204PbPb= 38.43676-38.56360, average 38.49171), thus consistent with the Pb in ores and volcanic host rocks having been derived from a common source that was island-arc Pb related to oceanic crust subduction. The northward subduction of the Palaeo-Qinling oceanic crust triggered dehydration of the slab, which generated a large amount of high-oxygen-fugacity aqueous hydrothermal fluid. The fluid rose into the mantle wedge, activated and extracted metallogenic material and promoted partial melting of the mantle wedge. The magma and ore-forming fluid welled up and precipitated, finally forming the Tongyu VHMS copper deposit.展开更多
BEFORE moving to China,my favorite hideaway was Hawaii,so I was delighted to learn China has its own Hawaii–southernmost Hainan Province.A Han Dynasty(206 BC-AD 220)emperor established a military garrison on Hainan I...BEFORE moving to China,my favorite hideaway was Hawaii,so I was delighted to learn China has its own Hawaii–southernmost Hainan Province.A Han Dynasty(206 BC-AD 220)emperor established a military garrison on Hainan Island,the largest island of Hainan Province,in 110 BC.Sun Yatsen recommended the establishment of a province in the region in 1906,but this did not happen until 1988,the year we moved to China.展开更多
文摘Diversity indices and abundance distribution models are statistical tools which ecologists have applied for decades for analyzing the intrinsic regularities of various ecological entities. In this work, we have applied these techniques to use the notions such as pedodiversity (as an example of geodiversity in a broad sense), in order to detect the differences and similarities between both natural resources, biological and non-biological. The discussion has mainly been conducted through the study of landform based pedodiversity analysis applied to SOTER digital databases in Hainan Island, China. The main analytical methods include indices of richness S that are the number of the categories (SOTER units relating to different soils in this work), indices based on proportional abundance of categories H' and E which are not only the number but also their relative abundance (in our case, the relative area occupied by each pedotaxa) is taken into account, models of the distribution of abundance of categories that provide the most complete description but also the least abridged and GIS mapping to show the spatial variation digitally.
基金Supported by the General Program of Zhejiang Science and Technology Department(No.2009C33004)
文摘Seventy-eight marine fungal strains were isolated from sediment samples collected off the coast of Nanji Island, Wenzhou, Zhejiang Province, China. Antibacterial screening using the agar disc method showed that 19 of the isolated strains could inhibit at least one pathogenic Vibrio from Pseudosciaena crocea. Subsequent screening confirmed that nine strains produced antibacterial metabolites that had activity against one or several types of pathogenic Vibrio. Strain NJ0104 had the widest antimicrobial spectrum and strong activity, particularly against Fibrio parahaemolyticus-MM0810072. A preliminary study of N J0104 antibacterial metabolites demonstrated that they had thermal stability up to 80℃, ultraviolet stability up to 40 min and pH stability between 4.0-7.0. In addition, the antibacterial metabolites were readily soluble in butanol. To identify the specific strain, the ITS-5.8S rDNA regions of NJ0104 were PCR amplified and sequenced. Based on the combination of phenotypic and genotypic data, the strain was identified as Arthrinium sp.
文摘Redetedrination of the metamorphic age of the gsrnet-bearing mafic wholeulite from the Sstrene Island, Esat Antarctica has been made and an isochron of wholerock-garnet-pyroxene-plagioclase is obtained, giving an age of [604±28(2σ)] Ma. Itis pointed out that this age represents the time of peak granulite facies metamorphism ofthe area. As to the geological relation of the Sstrene Island with the Bolingen Islandsand the Larsemann Hills to the east, it is deduced from the rock assemblages, metamorphic superposition, spatial changes and metamorphic ages between the above regions that the degree of the superposition of the later low pressure metamorphism is becoming stronger from west to east. While the evolution of the earlier medium pressure to later low pressure implies probably the substages of the same metamorphic cycle.
基金the National Park Service, U. S. Department of the Interior
文摘We quantified microhabitat use by white-footed mice Peromyscus leucopus in forest and old-field habitats occupied by Morrow' s honeysuckle Lonicera morrowii, an invasive exotic shrub imported from Japan. Microhabitat characteristics were compared between trails used by mice ( n = 124) and randomly selected trails ( n = 127) in 4 study plots located at Fort Necessity National Battlefield, Farmington, Pennsylvania, USA. We compared 10 mierohabitat variables between used and random trails using non-metric multidimensional scaling (NMDS) and classification and regression tree (CART) analysis. Trails used by mice were statistically different from randomly selected trails in both forested plots ( P 〈 0. 008) and old-field plots ( P 〈 0. 001 ). In the forested plots, trails of white-footed mice were more often associated with a greater percent cover (% cover) of coarse woody debris (CWD) than were randomly selected trails. In the old-field plots, mouse trails were commonly characterized by having a lower % cover of exotic herbaceous vegetation, a greater % cover of shrubs, and a greater % cover of Morrow' s honeysuckle than randomly selected trails. Our study indicates that white-footed mice do not move randomly and prefer areas of high structural complexity, thereby showing significant microhabitat preference. The preference of white-footed mice for areas with a relatively high percent cover of Morrow's honeysuckle could 1 ) be a factor in the aggressive nature of the exotic honeysuckle shrub's spread throughout the Battlefield or 2) cause the shrub to spread even faster into adjacent areas not yet occupied by Morrow' s honeysuckle
基金The Fundamental Research Funds for the Central Universities under contract No.18lgzd07the Key Research Program of Frontier Science+1 种基金CAS under contract No.QYZDB-SSW-DQC013-1the National Natural Science Foundation of China under contract No.41976128。
文摘The diversity,community composition and 16 S rRNA gene abundance of bacterioplankton along a transect across an upwelling area off the eastern coast of Hainan Island(the Qiongdong upwelling)were investigated in August of 2016 using high throughput sequencing and quantitative PCR assay of 16 S rRNA genes.Compared with the offshore stations,the inner-shelf stations had higher bacterial gene abundance(up to 3 fold)and operational taxonomic unit richness,a result of the influence of upwelled and fresher waters.Overall,a majority of the reads were affiliated with Gammaproteobacteria(11%-74%)and Alphaproteobacteria(14%-43%).The structure of the bacterial community was significantly affected by salinity,dissolved oxygen,NO_(3)^(-) and NH_(4)^(+),which also defined the physicochemical features of the upwelled waters.Horizontally,the relative abundances and gene abundances of Rhodobacteraceae,SAR86,Cyanobacteria and Bacteroidetes in eutrophic zone decreased from the inner to outer shelves and slope,whereas Alteromonas,Vibrio and Oceanospirillaceae exhibited an opposite trend.This study stresses the riverine influence on the oceanographic condition and spatial variability of bacterioplankton diversity and distribution in the Qiongdong upwelling.
文摘Exotic bush honeysuckles (</span><i><span style="font-family:Verdana;">Lonicera</span></i><span style="font-family:Verdana;"> spp.) are becoming increasingly common in the eastern and mid-western United States, but little is known about their impacts on invertebrates. We used a modified leaf vacuum to sample invertebrates in the shrub strata and understory of three shrub types (and open plots </span><span><span style="font-family:Verdana;">in the understory): single Morrow’s honeysuckle (</span><i><span style="font-family:Verdana;">L</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">morrowii</span></i><span style="font-family:Verdana;"> A. Gray) shrubs, </span></span><span style="font-family:Verdana;">single native southern arrowwood (</span><i><span style="font-family:Verdana;">Viburnum</span></i></span></span><span><span><i><span style="font-family:""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">recognitum</span></i></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> Fernald) shrubs, and dense thickets of Morrow’s honeysuckle, in southwestern PA, USA during 2004 and 2005. We also assessed the degree of </span><a name="OLE_LINK26"></a><a name="OLE_LINK25"></a><span style="font-family:Verdana;">herbivory</span><span style="font-family:Verdana;"> on the two species of shrubs. Within the shrub strata, invertebrate biomass was lower in southern arrowwood shrubs, but there was no difference in invertebrate abundance or family richness. Invertebrate abundance and richness were lowest </span><span style="font-family:Verdana;">in August, but there was no difference in biomass among the months. Invertebrate</span><span style="font-family:Verdana;"> abundance, biomass, and family richness were lowest in the understory below dense thickets of Morrow’s honeysuckle. Overall, the percent cover of herbs was the proximate factor responsible for driving patterns of invertebrate abundance, though ultimately these patterns were being driven by shrub type. Abundance and biomass of larval leaf chewers were highest in the native shrub;Morrow’s honeysuckle had a mean of 29.7 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area consumed per 1 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area, while the native shrub had a mean of 284.3 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> of leaf area consumed. Our results suggest that areas dominated by the exotic shrub negatively impact invertebrate biomass, which may in turn affect organisms at higher trophic levels.
文摘针对传统被动式检测方法存在较大检测盲区(Non-detection Zone,NDZ)、阈值难以确定以及易受电能质量扰动影响的缺陷,研究了一种基于奇异值分解(Singular Value Decomposition,SVD)和神经网络的被动式孤岛检测方法。该方法首先对公共连接点(Point of Common Coupling,PCC)处电压和逆变器输出电流进行S变换,提取相应的谐波幅值后,对其进行SVD并构成特征向量,最后运用BP神经网络对孤岛以及非孤岛情况进行分类识别。仿真结果表明,该方法可以有效检测出功率平衡情况下发生的孤岛,而且能防止电能质量扰动对检测准确性的影响,具有很高的准确性、可靠性和实用性。
基金Supported by the grants from Mjnistry of Public Health of China,No.98-1-303The Educational Committee of Shanghai,No.2000B02.
文摘AIM: To explore the association of methylation of the CpG island in the promotor of the p16 tumor suppressor gene with the clinicopathological characteristics of the colorectal cancers. METHODS: Methylation-specific PCR (MSP) was used to detect p16 methylation of 62 sporadic colorectal cancer specimens. RESULTS: p16 methylation was detected in 42% of the tumors.Dukes'staging was associated with p16 methylation status.p16 methylation occurred more frequently in Dukes'C and D patients (75.9%) than in Dukes'A and B patients (12.1%). CONCLUSION: p16 methylation plays a role in the carcinogenesis of a subset of colorectal cancer, and it might be linked to poor prognosis.
基金Under the auspices of the National Social Science Foundation of China(No.16BJY039)
文摘The urban heat island(UHI) effect has significant effects on the quality of life and public health. Numerous studies have addressed the relationship between UHI and the increase in urban impervious surface area(ISA), but few of them have considered the impact of the spatial configuration of ISA on UHI. Land surface temperature(LST) may be affected not only by urban land cover, but also by neighboring land cover. The aim of this research was to investigate the effects of the abundance and spatial association of ISAs on LST. Taking Harbin City, China as an example, the impact of ISA spatial association on LST measurements was examined. The abundance of ISAs and the LST measurements were derived from Landsat Thematic Mapper(TM) imagery of 2000 and 2010, and the spatial association patterns of ISAs were calculated using the local Moran’s I index. The impacts of ISA abundance and spatial association on LST were examined using correlation analysis. The results suggested that LST has significant positive associations with both ISA abundance and the Moran’s I index of ISAs, indicating that both the abundance and spatial clustering of ISAs contribute to elevated values of LST. It was also found that LST is positively associated with clustering of high-ISA-percentage areas(i.e.,>50%) and negatively associated with clustering of low-ISA-percentage areas(i.e.,<25%). The results suggest that, in addition to the abundance of ISAs,their spatial association has a significant effect on UHIs.
基金jointly supported by National Natural Science Foundation of China(Grant Nos.41421002,41272092,and 41030423)MOST Special Fund from the State Key Laboratory of Continental Dynamics,Northwest University,China
文摘The Tongyu copper deposit, located in the western part of the North Qinling Orogen, China, is one of several volcanic-hosted massive sulphide(VHMS) deposits with industrial value and is also a typical example of mineralization related to the subduction and metallogenesis during the Caledonian orogeny. We conducted systematic lead-sulphur isotope geochemical analyses of the Tongyu deposit to understand the possible ore-forming material sources and tectonic settings. Twenty-six sulphide samples yielded clustered δ^34SCDT values of 1.13‰-3.36‰, average 2.22‰, and show a tower-type distribution,implying that the sulphur of the Tongyu copper deposit mainly originated from a mantle source. The Pb isotope compositions of sulphides(^206Pb/^204Pb = 17.59225-18.56354, average 18.32020; ^207Pb/^204Pb =15.51770-15.69381, average 15.66217; ^208Pb/^204Pb= 37.99969-39.06953, average 38.52722) are close to the values of the volcanic host rocks(^206Pb/^204PbPb= 18.10678-18.26293, average 18.21158; ^207Pb/^204PbPb =15.63196-15.68188, average 15.65345; ^208Pb/^204PbPb= 38.43676-38.56360, average 38.49171), thus consistent with the Pb in ores and volcanic host rocks having been derived from a common source that was island-arc Pb related to oceanic crust subduction. The northward subduction of the Palaeo-Qinling oceanic crust triggered dehydration of the slab, which generated a large amount of high-oxygen-fugacity aqueous hydrothermal fluid. The fluid rose into the mantle wedge, activated and extracted metallogenic material and promoted partial melting of the mantle wedge. The magma and ore-forming fluid welled up and precipitated, finally forming the Tongyu VHMS copper deposit.
文摘BEFORE moving to China,my favorite hideaway was Hawaii,so I was delighted to learn China has its own Hawaii–southernmost Hainan Province.A Han Dynasty(206 BC-AD 220)emperor established a military garrison on Hainan Island,the largest island of Hainan Province,in 110 BC.Sun Yatsen recommended the establishment of a province in the region in 1906,but this did not happen until 1988,the year we moved to China.