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江西龙南花岗岩风化壳形成和演化的铀系不平衡约束

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地学前缘 2024年第4期31卷 366-379页

作者：贾国栋徐胜刘丛强天津师范大学京津冀生态文明发展研究院天津300387 天津大学地球系统科学学院天津300072

花岗岩风化壳在我国华南地区广泛分布,其形成和演化对地貌、生态环境和矿产资源等具有重要影响。作为风化壳最基本的参数之一,生成速率是理解风化壳形成和演化的关键因子。铀系不平衡法是当前广泛应用于确定风化壳生成速率的重要地球化... 详细信息

花岗岩风化壳在我国华南地区广泛分布,其形成和演化对地貌、生态环境和矿产资源等具有重要影响。作为风化壳最基本的参数之一,生成速率是理解风化壳形成和演化的关键因子。铀系不平衡法是当前广泛应用于确定风化壳生成速率的重要地球化学手段,由于稀释剂获取困难,我国开展的研究较少。本研究以江西龙南花岗岩风化壳剖面为研究对象,开展铀系不平衡研究以确定其生成速率。研究结果显示:风化壳剖面中U和Th的含量范围分别为(3.25~3.39)×10^(-6)和(41.46~47.67)×10^(-6);活度比(^(234)U/238U)a、(^(230)Th/^(234)U)a和(^(230)Th/^(232)Th)a范围分别为1.008~1.023、1.063~1.112和0.239~0.271。通过铀系不平衡法对铀系同位素进行拟合后得到风化壳20~120 cm区域的演化时间约为841 ka,据此确定风化壳的生成速率约为1.2 m/Ma。本研究中,控制风化壳生成速率的因素主要是表层覆盖,气候和构造的影响很小。此外,由于风化壳的生成速率远低于宇宙成因核素确定的剥蚀速率,因此风化壳的演化状态为厚度逐渐减小的非稳态。

关键词：铀系不平衡法生成速率花岗岩风化壳演化状态非稳态

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Interfacial processes and mechanisms of synergistic degradation of dichlorobiphenyl by white rot fungi and magnetite nanoparticles

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Science China Earth Sciences 2023年第9期66卷 2057-2065页

作者： Le CHANG Guanghui YU congqiang liu Institute of Surface-Earth System Science School of Earth System ScienceTianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai RimBohai Coastal Critical Zone National Observation and Research StationTianjin UniversityTianjin 300072China

The rapid increase in the artificial syntheses of organic pollutants has raised widespread ***,the mechanisms by which fungi degrade these new organic pollutants in the environment and adapt to environmental stressors remain *** this study,Phanerochaete chrysosporium,a model white rot fungus,was used to explore the interfacial processes and mechanisms for synergistic degradation of 4,4′-dichlorobiphenyl(PCB15)with magnetite *** results showed that after 3 and 5 days of cultivation with Phanerochaete chrysosporium alone,the rates for PCB15 degradation were 32%and 65%,respectively,indicating that the white rot fungus itself was able to degrade the organic ***,the addition of magnetite nanoparticles significantly enhanced the degradation of PCB15 by Phanerochaete *** cocultivation for 3 and 5 days,the rates for PCB15 degradation increased to 42%and 84%,*** radiation-based Fourier transform infrared spectromicroscopy(SR-FTIR)showed that the magnetite particles were tightly adhered to the fungal hyphae and were unevenly distributed on the hyphal ***,cocultivation of the fungus and magnetite nanoparticles significantly enhanced the nanozymatic activity of magnetite.A linear regression model provided a significantly negative correlation(r=−0.96,p<0.001)between the nanozymatic activity of the magnetite and the concentration ratio of the PCB15,supporting the hypothesis that white rot fungi degraded the PCB15 by enhancing the nanozyme activity of ***-resolution X-ray photoelectron spectroscopy(XPS)revealed that the nanozymatic activity of magnetite was mainly governed by oxygen vacancies on the mineral surfaces rather than the iron ***,these findings increase our understanding of the powerful capabilities of fungi in terms of stress resistance and adaptation to extreme environments and provide new insights into fungal-mediated degradation of organic po

关键词： Magnetite nanoparticles Nanozymes Oxygen vacancies White rot fungi X-ray photoelectron spectroscopy Synchrotron radiation based FTIR spectromicroscopy Dichlorobiphenyl

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人类世生物地球化学循环及其科学

地学前缘 2024年第1期31卷 455-466页

作者：刘丛强李思亮刘学炎王宝利郎赟超丁虎郝丽萍张琼予天津大学地球系统科学学院、表层地球系统科学研究院天津300072 天津环渤海滨海地球关键带国家野外科学观测研究站天津300072 物质绿色创造与制造海河实验室天津300192

地球已进入新的地质时代——“人类世”,人类已成为全球变化的主要驱动力。人类活动导致的地球生态系统的生物地球化学过程及关键生源要素的生物地球化学循环的改变直接或间接地影响着地球生态系统的关键功能,给人类福祉和可持续发展带... 详细信息

地球已进入新的地质时代——“人类世”,人类已成为全球变化的主要驱动力。人类活动导致的地球生态系统的生物地球化学过程及关键生源要素的生物地球化学循环的改变直接或间接地影响着地球生态系统的关键功能,给人类福祉和可持续发展带来诸多威胁。本文基于地球系统科学研究的新进展,综述了人类世全球变化特征、生物地球化学循环在地球系统各圈层演化中的作用及其变化规律。特别关注了自然资源开发利用、生产和消费模式改变等人类活动对生物地球化学循环的影响,以及由此产生的气候、生态和环境效应。研究表明,应对人类世全球变化需要系统理解人类活动作为主要驱动力的多要素和多尺度生物地球化学循环过程及其生态和环境效应,基于地球系统科学的理论与方法开展针对人类世社会-生态系统的自然科学和社会科学的交叉融合研究。在文末提出了人类世生物地球化学研究的优先领域和方向,并强调解决受人类活动和气候变化高度影响下人类世生物地球化学循环的各种复杂科学问题的迫切性和重要性。

关键词：人类世生物地球化学循环全球变化地球系统科学

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Geochemical behavior of lithium isotopes in a small mountainous river of the Tibetan Plateau:A case study from Niyang River

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Science China Earth Sciences 2023年第8期66卷 1853-1864页

作者： Junwen ZHANG Yani YAN Zhiqi ZHAO congqiang liu School of Earth Science and Resources Chang’an UniversityXi’an 710054China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China

Lithium(L_(i))and its isotopes are potential tracers of silicate weathering in river ***,the relationship between the Li isotopic composition(δ~7Li)in rivers and silicate weathering intensity remains *** study analyzed the Li concentration and isotopic composition in river waters from the Niyang River,southern Tibetan *** results show that these samples have significantly variable Li concentrations(0.31–7.4μg/L)andδ~7Li values(+7.0–+20.7‰,n=28),and highδ~7Li values are found in several *** indicate that dissolved Li in river water is predominantly derived from silicate weathering and geothermal *** the exception of certain tributaries,geothermal water contributes 68%to 85%of the dissolved *** waters have lowδ~7Li values(-0.9–+2.9‰)in the Tibetan *** in the proportional contribution of dissolved Li in river samples from silicate weathering and geothermal water may be the main reason for the spatiotemporal variation in riverineδ~7Li *** samples have higherδ~7Li values when the dissolved Li in the water samples is mainly derived from silicate weathering contributions,and lower values when the contribution from geothermal waters is ***,the interaction of dissolved Li from geothermal water with secondary minerals results in Li isotopic fractionation,which may contribute to variations in river waterδ~*** is accepted that the lower weathering intensity in orogenic(or mountainous)belts compared to floodplains is the main controlling factor for lowerδ~7Li values in the *** study indicates that geothermal water input may cover the Li isotope signal of silicate weathering in river water,which in turn,affects the accurate understanding of the relationship between riverineδ~7Li values and the silicate weathering ***,whether the lowerδ~7Li values of river waters in hydrothermal-rich orogenic belts are mainly controlled by the regional weathering intensi

关键词： Lithium isotopes Silicate weathering Hot springs Tibetan Plateau

Risk assessment and binding mechanisms of potentially toxic metals in sediments from different water levels in a coastal wetland

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Journal of Environmental Sciences 2023年第7期129卷 202-212页

作者： Fusheng Sun Guanghui Yu Xingxing Han Zhilai Chi Yunchao Lang congqiang liu Institute of Surface-Earth System Science School of Earth System ScienceTianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai RimTianjin UniversityTianjin 300072China

The excessive accumulation of potentially toxic metals(Pb and Cd)in coastal wetlands is among the main factors threateningwetland ***,the effects ofwater table depth(WTD)on the risk and binding mechanisms of potentially toxic metals in sediments remain ***,sediments from different WTD obtained from a typical coastal wetland were evaluated using a newly developed strategy based on chemical extraction methods coupled with high-resolution *** findings indicated that the WTD of the coastal wetland fluctuates frequently and the average enrichment factor for Pb was categorized as minor,whereas Cd enrichment was categorized as ***-resolution spectroscopy techniques also demonstrated that organic functional groups and partly inorganic compounds(e.g.,Fe-O/Si-O)played a vital role in the binding of Pb and Cd to surface ***,mineral components rather than organic groups were mainly bound to thesemetals in the bottom ***,our findings provide key insights into the potential health effects and binding characteristics of potentially toxic metals in sediments,as well as their dynamic behavior under varying sediment depths at a microscale.

关键词： Coastal wetlands Wetland sediment Toxic metals Risk assessment Synchrotron radiation Binding mechanisms

Deciphering non-steady landscape evolution by in-situ cosmogenic nuclide depth profile

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Science China Earth Sciences 2022年第3期65卷 490-502页

作者： Ye YANG Lifeng CUI Sheng XU Zhenping CAO Shuncheng ZHANG congqiang liu Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China

In-situ cosmogenic nuclide s are receiving growing attention in surface Earth system science in which the steady-state denudation is an important assumption for estimating the surface denudation of long-lived(103-106 years)***,distinguishing steady-state denudation and deciphering a reliable denudation rate from non-steady state denudation region are *** depth profile models for investigating the denudation rate,exposure age and inheritance are widely used for sediment and regolith of steady-state denudation *** we present in-situ co smogenic nuclides^(10)Be and^(26)Al from two typical granite regolithes from Jixian in Tianjin and Tengchong in Yunnan to model non-steady landscape evolution process by using steady state(Model 1)and non-steady state(Model 2,continuous exposure;Model 3 a,changed denudation rate;Model 3 b,abrupt denudation event)*** results of steady state model show that both regolithes are in non-steady state.^(10)Be non-steady state models of Jixian regolith reveal that the surface has likely experienced a denudation rate change or an abrupt denudation event during the past several millennia,resulting in a non-steady *** similar Model 3 a and 3 b denudation rates of 14.6-12.9^(+9.4)and 14.7-14.7^(+9.0)mmkyr^(-1),respectively,might demonstrate the long-term denudation rate rather than the exaggerated rate s of 39.0-2.3^(+2.6)and 39.0-2.4+^(2.5)mm kyr^(-1)calculated by assuming steady-state denudation and ignoring *** non-steady state model results of Tengchong regolith suggest that the surface has likely experienced a strong denudation about 157 ka(^(10)Be)or 127 ka(^(26)Al)*** timing is basically consistent with the termination of the MIS 6(TII:130 ka)and the climate change events in the Tibetan Plateau,suggesting a strong surface landscape denudation during the transition from glacial to *** compiling of basin-wide denudation rates in the Tibetan Plateau shows a good positi

关键词： Denudation rate Landscape evolution Quaternary geochronology Depth profile Cosmogenic nuclides

Metamorphic fluxes of water and carbon in rivers of the eastern Qinghai-Tibetan Plateau

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Science China Earth Sciences 2022年第4期65卷 652-661页

作者： Jun ZHONG Siliang LI Zheng LI Xuetao ZHU Yuanbi YI Tingting MA Sheng XU congqiang liu Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China School of Environment Tsinghua UniversityBeijing 100084China

Geothermal activities are common in active orogenic zones and play an important role in surface-earth geochemical *** we analyzed the water chemical compositions,stable and radioactive carbon isotopes of dissolved inorganic carbon(δ^(13)CDICandΔ^(14)CDIC)of hot springs and large rivers in the eastern Qinghai-Tibetan Plateau(QTP).The hot springs had major ions’concentrations varying in a wide range,and most hot springs’alkalinities resulted from high-temperature silicate *** observed hot springs’waters were affected by the mixing of metamorphic fluids and surface waters,which altered the water chemistry andΔ^(14)CDICof the hot *** the observedΔ^(14)CDICin hot springs was much higher than the theoreticalΔ^(14)CDICin metamorphic fluids(i.e.,-1000‰),we used an isotopic mass balance approach(i.e.,Δ^(14)CDIC)to quantify the contribution of surface waters to the hot *** the ions of metamorphic fluids were calibrated byΔ^(14)CDIC,the metamorphic water fluxes were calculated by the chemical mass balance approach of Ge/Si ratios,using the Monte-Carlo *** found that the proportion of metamorphic water fluxes to the river discharge ranged from 0.17%for the Yellow River to 0.52%for the Jinsha River,and it would be much higher in some *** horizontal metamorphic contributions of alkalinity to the large rivers ranged from 0.87%to 3.96%in eastern QTP,and the vertical metamorphic carbon outgassing would be much *** metamorphic fluids fluxes estimated in this study were much lower than previous estimations extrapolated from small Himalayan rivers,and thus we thought that the previous estimations of metamorphic carbon fluxes in QTP were likely *** propose that systematic studies are needed to be conducted to constrain the metamorphic carbon flux in *** study shed light on the release of metamorphic carbon in the orogenic zone,placing limits on the results of orogenic forcing on chemical weatherabili

关键词： Geothermal activities Δ^(14)CDIC Ge/Si ratio Qinghai-Tibetan Plateau Metamorphic carbon

Degassing of deep-sourced CO_(2) from Xianshuihe-Anninghe fault zones in the eastern Tibetan Plateau

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Science China Earth Sciences 2022年第1期65卷 139-155页

作者： Sheng XU Lufeng GUAN Maoliang ZHANG Jun ZHONG Wei liu Xian'gang XIE congqiang liu Naoto TAKAHATA Yuji SANO Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China Atmosphere and Ocean Research Institute The University of TokyoKashiwaChiba 277-8564Japan

A large number of gases are releasing from the medium-high temperature geothermal fields distributed along the large-scale strike-slip fault zones in the southeastern margin of the Tibetan *** this study,11 hot spring water and the associated bubbling gas samples were collected along the Xianshuihe-Anninghe fault zones(XSH-ANHFZ)and analyzed for chemical and isotopic *** δ^(18)_(H_(2)O) and δD_(H_(2)O) values indicate that hot spring waters are predominantly meteoric origin recharged from different *** water samples are significantly enriched in Na^(+) and HCO_(3) due to the dissolution of regional evaporites,carbonates and Na-silicates.^(3)He/^(4)He ratios of the gas samples are 0.025-2.73 times the atmospheric *** ^(3)He/^(4)He ratios are high in the Kangding region where the dense faults are distributed,and gradually decrease with increasing distance from Kangding towards both sides along the Xianshuihe fault zones(XSHFZ).Hydrothermal fluids have dissolved inorganic carbon(DIC)concentrations from 2 to 42 mmol L^(-1),δ^(13)C_(DIC) from -6.9‰ to 1.3‰,δ^(13)C_(CO_(2)) from -7.2‰ to -3.6‰ and Δ^(14)C from -997‰ to -909‰.Combining regional geochemical and geological information,the CO_(2)sources can be attributed to deep-sourced CO_(2)from mantle and metamorphism of marine carbonate,and shallow-sourced CO_(2)from the dissolution of marine carbonate and biogenic CO_(2).The mass balance model shows that 11±6% of the DIC is sourced from the dissolution of shallow carbonate minerals,9±8% formed by pyrolysis of sedimentary organic matter,80±9% derived from deep metamorphic origin and mantle-derived CO_(2).Among them,the deep-sourced CO_(2)in Anninghe fault zones(ANHFZ)is merely metamorphic carbon,whereas ca.12% and ca.88% of the deep-sourced CO_(2)in the XSHFZ are derived from the mantle and metamorphic carbon,*** average deep-sourced CO_(2)flux in the Kangding geothermal field is estimated to be 160 ta^(-1).If all the hot

关键词： Hot spring Fluid geochemistry Deep-sourced carbon Xianshuihe-Anninghe fault zones Tibetan Plateau

Discrimination between extraneous nitrogen input and interior nitrogen release in lakes

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Science China Earth Sciences 2004年第9期47卷 813-821页

作者： XIAO Huayun liu congqiang The Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China The Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

In this study the authors determined the nitrogen isotopes of nitrate and the carbon and nitrogen contents of water samples from the Hongfeng Lake and inflowing streams, and, on this basis, discriminated the extraneous nitrogen input and the interior nitrogen release (organic matter decomposition) in the lake. The results showed that the amount of extraneous nitrogen input into the Hongfeng Lake increases and the interior nitrogen release from the lake is intensified in winter and spring. Nitrogen mixing is relatively obvious at the catchments between the lake inlet and inflowing streams, while organic matter decomposition (nitrification) is most intense in the middle and lower reaches of the lake. In winter and spring the organic matter decomposition takes place mainly at the middle level of the water column in the middle and lower reaches of the lake, which has a bearing on the abundance of degraded organic matter at this water level. This part of degraded organic matter contains a considerable proportion of hydrogenous nitrogen in the lake.

关键词： extraneous nitrogen input, interior nitrogen release, Hongfeng Lake.