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Frontiers of Earth Science 2012年第1期6卷 95-100页

作者： Xianyu HUANG jiantao xue Shouyu GUO State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China Key Laboratory of Systematic Mycology and Lichenology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Five coticolous lichen samples were collected from western Hubei Province of China to analyze the long chain n-alkanes and their carbon isotope compositions. The n-alkanes range in carbon number from C17 to C33 with strong odd-over-even predominance between C21 and C33. Lichens are dominated by n-C29 in the samples of Dajiuhu, Shennongjia Mountain, but by both n-C23 and n- C29 at Qizimei Mountain. This difference may result from the different environmental conditions in these two sites. The δ13C values of long chain n-alkanes in lichen samples show the signature of C3 plants. Based on compound- specific carbon isotopic values and previous results, we state that alkane homologs 〉 C23 mainly originate from the symbiotic fungi, while symbiotic algae only contribute trace amount of long chain alkanes. Of great interesting is the occurrence of long chain 3-methylalkanes in the Qizimei samples. These anteiso compounds range from C24 to C32, displaying obvious even-over-odd predomi- nance. This study reveals that the association of long chain 3-methylalkanes with n-C23 alkane might be used as proxies to reconstruct the paleoecological implications of lichens in Earth history.

关键词： lichen alkarle 3-methylalkanes n-C23 alkane,compound specific carbon isotope

Environmental impacts on the distribution of microbial tetraether lipids in Chinese lakes with contrasting pH: Implications for lacustrine paleoenvironmental reconstructions

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Science China Earth Sciences 2016年第2期59卷 939-950页

作者： DANG XinYue xue jiantao YANG Huan XIE ShuCheng School of Earth Sciences China University of Geosciences State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

Glycerol dialkyl glycerol tetraethers(GDGTs) in lake sediments are useful biomarkers for the continental paleoclimatic reconstruction. However, the environmental controls on the distribution of these compounds, in particular the 6-methyl isomers of bacterial branched GDGTs(bGDGTs), in the lakes with contrasting pH, are still unknown, hindering their application for paleo-reconstructions. Here, we investigated the environmental impacts on the distribution of GDGTs in 17 alkaline lakes and 1 acid lake in China. It was found that the dissolved oxygen content in water column may have an impact on the distribution of archaeal isoprenoid GDGTs(iGDGTs) by causing the change in archaeal communities. The ratio of GDGT-0/crenarchaeol increases with decreasing oxygen content, indicating that the relative abundance of anaerobic methanogenic archaea or Miscellaneous Crenarchaeotic Group(MCG) vs. aerobic Thaumarchaeota is controlled by the oxygen content dissolved in water of these lakes. Thaumarchaeota are likely to contribute only a small proportion of iGDGTs in the relatively oxygen-depleted lakes, and thus TEX_(86) is not suitable for the reconstruction of the surface temperature of these lakes. The abundance ratio of iGDGTs to bGDGTs(R_(i/b)) appears to show no relationship with water pH in all the lakes, but exhibits a significant positive correlation with the water depth of the acid Lake Qinghai in Tengchong. As expected, the methylation degree of bGDGTs(MBT′) was found to correlate with both mean annual air temperature(MAT) and water pH, and the cyclization degree of bGDGTs(CBT) correlates only with water pH in these lakes. However, the MBT′_(5ME), an index to measure the methylation degree of 5-methyl bGDGTs, exhibits no relationship with MAT, whereas MBT′_(6ME), the methylation degree of 6-methyl bGDGTs, was found to correlate significantly with MAT. This is opposite to the situation observed in the global soils, pointing to a different adaptation of b GDGT-producing ba

关键词： GDGTs Lake 6-methyl bGDGTs pH IR

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Seasonal variations of leaf wax n-alkane distributions and δ^(2) H values in peat-forming vascular plants from the Dajiuhu peatland, central China

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Frontiers of Earth Science 2022年第3期16卷 774-785页

作者： jiantao xue xueying ZHANG Jinzhi LI Zhiqi ZHANG Huaiying YAO Research Center for Environmental Ecology and Engineering School of Environmental Ecology and Biological EngineeringWuhan Institute of TechnologyWuhan 430073China Administration of Dajiuhu National Wetland Park of Shennongjia Shennongjia 442417China Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Leaf wax n-alkane compositions have been widely applied to reconstruct paleoclimate histories in peat deposits,yet understanding of how the n-alkanes vary during seasonal plant growth remains *** we report variations in the molecular and wax-derived nalkane hydrogen isotope(δ^(2) Halk)in the three dominant vascular plant species(Sanguisorba officinalis,Carex argyi,Euphorbia esula)and surface peat deposits nearby from the Dajiuhu peatland over a growing *** three species show a relatively high carbon preference index(CPI)in the beginning of the growing season,with the CPI values reaching as high as 50 in two of the three *** species(***,***)display relatively stable average chain length(ACL)values over the four sampling intervals,with standard derivations of *** contrast,*** exhibits a significant fluctuation of ACL values(averaging 28.11.4)over the growing ***δ^(2) Halk in all three species decreased during leaf *** the final stage of growth,theδ^(2) Halk values of the three species are similar to those in the surface peats collected from the *** the results of our measurements of alkane concentration andδ^(2) H values,it is likely that de novo synthesis of leaf wax n-alkanes in the peatforming plant species is mainly at the early stage of leaf *** the following months,the removal process exceeds renewal,resulting in a general decrease of the concentration of the total n-alkanes and the integratedδ^(2) Halk *** theδ^(2) Halk values probably integrate the environmental variations at the end of the plant growth period rather than the whole period or the early growth *** results are significant and have the potential to improve the utility ofδ^(2) Halk values in paleoenvironmental reconstructions.

关键词： peat-forming vascular plants n-alkanes δ^(2)H ratio seasonal variations central China

Main environmental drivers of abundance,diversity and community structure of comammox Nitrospira in paddy soils

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Pedosphere 2023年第5期33卷 808-818页

作者： Fuyun GAO Yaying LI Haoxin FAN jiantao xue Huaiying YAO Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control CAS Haixi Industrial Technology Innovation Center in BeilunNingbo 315800China University of Chinese Academy of Sciences Beijing 100049China Research Center for Environmental Ecology and Engineering School of Environmental Ecology and Biological EngineeringWuhan Institute of TechnologyWuhan 430073China

The recently discovered complete ammonia oxidizers comammox Nitrospira contain clades A and B that can establish an independent one-step nitrification process;however,little is known about their environmental drivers or habitat distributions in agricultural *** studies on comammox Nitrospira in paddy soils have mainly focused on small-scale samples,and there is a lack of multisite research on comammox Nitrospira in paddy *** this study,we conducted a survey of 36 paddy soils to understand the community structure,abundance,and diversity of comammox Nitrospira and the degree to which they are affected by environmental factors at a large *** Nitrospira were found to be widely distributed among the paddy *** abundance of comammox Nitrospira clade A was mostly lower than that of clade B,whereas its diversity was mostly higher than that of clade *** analysis showed that multiple factors affected(P<0.05)the abundance of comammox Nitrospira,including soil pH,organic matter,total carbon,and total nitrogen,latitude,mean annual temperature,and mean annual ***,there was a clear relationship between the comammox Nitrospira community and habitat,indicating that some amplicon sequence variants(ASVs)had a unique dominant position in specific *** analysis showed that the ASVs of comammox Nitrospira clade A clustered with the known sequences in the paddy soils and were significantly different from the known sequences in other habitats,which may be related to the unique paddy field *** contrast,comammox Nitrospira clade B showed no clear habitat *** results support the wide distribution and high abundance of comammox Nitrospira in paddy soils and provide novel insights into nitrogen cycling and nutrient management in agricultural ecosystems.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria amplicon sequence variant complete ammonia oxidizer environmental factor habitat nitrification nitrogen cycling

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赤壁市茶园土壤多环芳烃季节分布的特征分析

武汉工程大学学报 2024年第2期46卷 175-183页

作者：李金枝薛建涛冯雪晴冯俊俊张雪莹武汉工程大学绿色化工过程教育部重点实验室环境生态与生物工程学院湖北武汉430205

土壤是持久性有机污染物多环芳烃(PAHs)的主要归趋之一,城市、农业、工业等土壤中PAHs浓度水平、污染来源及风险评估等研究得到了广泛的关注。采用气相色谱质谱联用法对赤壁市太平口村茶园土壤PAHs的分布、来源及生态风险评价进行了季... 详细信息

土壤是持久性有机污染物多环芳烃(PAHs)的主要归趋之一,城市、农业、工业等土壤中PAHs浓度水平、污染来源及风险评估等研究得到了广泛的关注。采用气相色谱质谱联用法对赤壁市太平口村茶园土壤PAHs的分布、来源及生态风险评价进行了季节差异分析。结果表明:茶园土壤中16种PAHs的总浓度为18.38~154.44 ng·g^(-1),平均值71.33 ng·g^(-1);夏季土壤中PAHs浓度略高于冬季。整体上茶园土壤中PAHs是以5~6环组成为主,但在冬季有25%样点是以2~3环为主。通过源解析发现,赤壁市茶园土壤PAHs主要来自石油燃烧,木材及煤炭燃烧等混合燃烧源。其中冬季土壤PAHs还存在石油输入源。茶园土壤中总有机碳(TOC)与总PAHs存在显著的相关性(r^(2)=0.46,p≤0.05),其中与高环PAHs之间存在显著相关性(r^(2)=0.5,p≤0.01),与低环PAHs不存在相关性(r^(2)=0.13,p≥0.05)。生态风险评价结果表示,尽管赤壁市茶园土壤PAHs整体生态风险相对较低,但也存在一定致癌风险,其中以苯并(b)荧蒽(BbF)、二苯并(a,h)蒽(DahA)和茚并(1,2,3-cd)芘(InP)的毒性当量浓度贡献最大。

关键词：多环芳烃茶园土壤季节差异源解析风险评价

“九湖梨壳虫（Nebela jiuhuensis）”的形态特征及其生态地理学意义

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第四纪研究 2018年第4期38卷 1050-1056页

作者：巩静许元韧薛建涛秦养民中国地质大学(武汉)地球科学学院湖北武汉430074 中国地质大学(武汉)生物地质与环境地质国家重点实验室湖北武汉430074

有壳变形虫是一类具外壳的单细胞原生动物，广泛栖息在泥炭藓表面、湿润的土壤和淡水湖泊环境中。它们对环境变化敏感，其壳体能够在沉积物中保存下来，因而记录了丰富的环境变化信息。近20年以来，有壳变形虫在生物多样性、生态指示和... 详细信息

有壳变形虫是一类具外壳的单细胞原生动物，广泛栖息在泥炭藓表面、湿润的土壤和淡水湖泊环境中。它们对环境变化敏感，其壳体能够在沉积物中保存下来，因而记录了丰富的环境变化信息。近20年以来，有壳变形虫在生物多样性、生态指示和古环境重建方面得到了广泛应用。近年来，我国对有壳变形虫的研究不断深入，陆续发现了一些新种和中国新纪录种，极大地丰富了我国有壳变形虫的物种名录。在前期的研究中，在我国长江中游地区的神农架大九湖泥炭湿地发现了一个有壳变形虫的新物种：九湖梨壳虫（Nebela jiuhuensis Qin，Mitchell＆Lara，2016），本文对这一物种的形态特征、分类地位、生态习性和地理分布进行了详细的描述，该物种的壳体梨形，侧面观壳体扁平，两侧有龙骨结构环绕，个体相对较大，壳长为216±8.44 μm，壳宽为122±6.24 μm，壳体测量特征的变异范围较小，具有较为稳定的形态特征。九湖梨壳虫目前发现于我国神农架、华南地区中部和朝鲜半岛的泥炭湿地中水位较高的地带。本文还讨论了该物种在生态指示、古环境重建和生物地理学等方面的意义。

关键词：有壳变形虫泥炭湿地九湖梨壳虫生物地理学指示种

鄂西亚高山泥炭地有壳变形虫生态监测及对水位的指示意义

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地球科学 2018年第11期43卷 4036-4045页

作者：秦养民巩静顾延生薛建涛向成玉吴未华葛继稳中国地质大学地球科学学院湖北武汉430074 中国地质大学生物地质与环境地质国家重点实验室湖北武汉430074 中国地质大学环境学院湖北省湿地生态与环境恢复重点实验室湖北武汉430074 湖北省二仙岩湿地自然保护区管理局湖北恩施445000

开展湿地的生态监测研究是理解当今气候变化背景下湿地的生态响应、动态演化和生态服务功能变化的有效途径,也是湿地保护、科学管理、合理规划和生态恢复的内在需求.以我国鄂西地区广泛分布的典型亚高山泥炭湿地为研究地点,以在湿地中... 详细信息

开展湿地的生态监测研究是理解当今气候变化背景下湿地的生态响应、动态演化和生态服务功能变化的有效途径,也是湿地保护、科学管理、合理规划和生态恢复的内在需求.以我国鄂西地区广泛分布的典型亚高山泥炭湿地为研究地点,以在湿地中大量生活且对环境变化敏感的环境指示生物——有壳变形虫为研究对象,采用了一种较新的泥炭湿地水位长期定点监测方法——"PVC印迹法"监测湿地水位的长期变化,调查了有壳变形虫的生物多样性、群落组合特征及其与水位等主要环境因子的响应关系,共记录到有壳变形虫27种和类群(type),隶属14个属.对有壳变形虫的群落组成与环境因子的关系排序分析显示,泥炭湿地的水位是有壳变形虫群落组成的主控环境因子,构建了有壳变形虫属种与水位的转换函数,该函数具有较好的预测和推导能力(R2=0.62),为该地区泥炭湿地的古水位重建提供了现代过程的数据支持.

关键词：有壳变形虫泥炭地监测水位转换函数鄂西

基于Citespace Ⅴ的绿色物流发展研究知识图谱分析

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长春理工大学学报（社会科学版） 2021年第2期34卷 103-110页

作者：薛建涛武佩剑安徽财经大学工商管理学院安徽蚌埠233030

以CNKI数据库中2000-2018年1 652篇绿色物流期刊论文为研究对象,借助信息可视化软件Citespace Ⅴ对相关数据进行处理,绘制作者合作网络、机构合作网络、关键词共现及聚类网络、突现词检测分析。研究发现:国内作者和机构尚未形成紧密化合... 详细信息

以CNKI数据库中2000-2018年1 652篇绿色物流期刊论文为研究对象,借助信息可视化软件Citespace Ⅴ对相关数据进行处理,绘制作者合作网络、机构合作网络、关键词共现及聚类网络、突现词检测分析。研究发现:国内作者和机构尚未形成紧密化合作,并呈现大分散、小集中的局面。研究热点主要从物流环节层面、行业层面、环保层面、发展模式层面和发展对策层面展开。突现词归纳发现,绿色供应链管理是绿色物流研究的永恒主题,物流过程的绿色化是绿色物流研究的主导方向,低碳经济是绿色物流研究的新思维。

关键词：绿色物流 Citespace 科学知识图谱

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长江中游赤壁段农业用地多环芳烃来源解析

环境科学与技术 2021年第4期44卷 104-111页

作者：孙岳宏王语嫣刘冲张雪莹陈朝娟薛建涛武汉工程大学环境生态与生物工程学院绿色化工过程教育部重点实验室湖北武汉430205

该文利用气相色谱-质谱联用法检测了长江中游沿岸赤壁市太平口村不同农业用地的多环芳烃的含量、组成,借助异构体比值法及生态风险评价法对这些农田土壤多环芳烃(PAHs)进行了源解析及生态风险评价。结果显示,种植玉米、大豆、棉花、水... 详细信息

该文利用气相色谱-质谱联用法检测了长江中游沿岸赤壁市太平口村不同农业用地的多环芳烃的含量、组成,借助异构体比值法及生态风险评价法对这些农田土壤多环芳烃(PAHs)进行了源解析及生态风险评价。结果显示,种植玉米、大豆、棉花、水稻和茶树的土壤中检测的16种优控PAHs含量在91.55~543.02 ng/g之间,其中种植玉米、大豆、棉花、水稻4种作物的土壤PAHs以中高环数为主且种植水稻土壤含量最高,可能由水稻种植过程中灌溉活动贡献。种植茶树土壤含量最低且以低环数PAHs为主,可能和茶树种植的地理位置和PAHs扩散作用相关。源解析表明,这些农业用地土壤中PAHs主要来源是燃烧源,比如木材秸秆燃烧、煤炭燃烧等。生态风险评价表明,长江中游沿岸赤壁市太平口村农田土壤存在一定的PAHs致癌风险,茚并[123-cd]芘和苯并[a]芘是主要的致癌化合物。通过和长江流域及其他地区土壤PAHs对比发现,在太平口村实施的秸秆焚烧等管控措施对减少PAHs在长江沿岸农田土壤的积累有一定的积极作用。

关键词：长江中游多环芳烃农业用地源分析风险评价

价值链赋能:传统企业竞争优势进阶路径研究——以天之红祁门红茶为例

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山东科技大学学报（社会科学版） 2023年第1期25卷 95-107页

作者：武佩剑朱岚岚薛建涛安徽财经大学工商管理学院安徽蚌埠233030

以天之红祁门红茶为例,采用单案例研究的方式,基于其1997—2021年的企业发展历程,分析探讨传统企业的竞争优势进阶路径过程及背后机理。研究发现:天之红的竞争优势进阶路径分为三阶段,萌芽期以基础价值链识别价值增值环节与活动,优化并... 详细信息

以天之红祁门红茶为例,采用单案例研究的方式,基于其1997—2021年的企业发展历程,分析探讨传统企业的竞争优势进阶路径过程及背后机理。研究发现:天之红的竞争优势进阶路径分为三阶段,萌芽期以基础价值链识别价值增值环节与活动,优化并加强生产经营活动以提高运营效率,获取基础性竞争优势。扩张期以产业生态链的方式扩大基础竞争优势,夯实生态圈基础设施,构建多产业协同的生态链和生态优势,形成持续性竞争优势。成熟期以智慧链联结企业价值链与生态链,重构管理模式,提高资源配置能力与需求响应变化能力,形成系统性竞争优势。研究以价值链为基础,总结天之红发展成功经验,以期为其他传统企业运用价值链升级提升自身竞争优势提供路径借鉴。

关键词：价值链竞争优势进阶路径案例研究