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斯洛文尼亚岩溶区草地生长季土壤CO变化及其降雨效应

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地球学报 2024年

作者：章程肖琼汪进良孙平安苗迎郭永丽 Mitja PRELOVSEK Martin knez Sa?a MILANOVI? 中国地质科学院岩溶地质研究所/联合国教科文组织国际岩溶研究中心自然资源部/广西岩溶动力学重点实验室斯洛文尼亚科学与艺术院岩溶研究所塞尔维亚贝尔格莱德大学水文地质系岩溶水文地质中心

土壤CO2是岩溶作用的核心驱动因子,也是研究土壤呼吸及其与大气CO2源汇关系的核心指标。快速的岩溶动力学和碳循环过程及其对生态系统的敏感性,暗示其在现今全球碳循环中仍在发挥积极作用。本文以斯洛文尼亚第纳尔岩溶区典型草地土壤生... 详细信息

土壤CO2是岩溶作用的核心驱动因子,也是研究土壤呼吸及其与大气CO2源汇关系的核心指标。快速的岩溶动力学和碳循环过程及其对生态系统的敏感性,暗示其在现今全球碳循环中仍在发挥积极作用。本文以斯洛文尼亚第纳尔岩溶区典型草地土壤生态系统为例,开展不同深度土壤温度、水分和土壤CO2含量等指标高分辨率在线监测。监测工作在2021年6—9月草地生长季进行,每10 min记录一组数据。结果表明,土下20 cm、30 cm和50 cm土温均值分别为19.69℃、18.54℃和17.42℃,暗示土温随深度增加逐渐变小。土下20 cm、30 cm和50 cm水分含量均值分别为23.2%、21.7%和24.9%。土壤水分变化主要受降雨控制,降雨强度越大,水分上升幅度越大。土下20cm、30cm和50cm土壤CO2变化范围分别为(1 884～6 705)×10–6、(2 088～5 516)×10–6、(2 771～3 606)×10–6,均值分别为3 578×10–6、3 468×10–6、3 174×10–6。无雨期间土壤水分显示出白天下降,夜晚基本保持不变的阶梯状下降趋势,受土壤水分控制,土壤CO2多日总体变化呈现锯齿状持续降低趋势。不同降雨条件下均出现土壤CO2向下迁移现象,从强降雨过程初期产生的土壤CO2含量快速下降看,表明雨水入渗产生的脉冲效应导致CO2快速向下迁移,进一步进入下伏岩溶含水层,可为碳酸盐岩溶蚀提供CO2驱动力,比较下降幅度与雨前CO2含量,暗示降雨过程中12%～33%的土壤CO2进入岩溶含水层并参与碳酸盐岩溶蚀。监测结果暗示岩溶作用是陆地生态系统碳循环的横向延伸,具有土壤CO2汇效应,也就是说,岩溶作用过程具有缓解土壤CO2向大气释放功能,即减源效应。因此,在研究岩溶区碳循环及其碳汇效应时,应把植被-土壤-碳酸盐岩溶蚀作为一个整体,从岩溶关键带角度,系统开展监测与研究,以期获得岩溶区碳循环过程的完整认识,揭示其碳汇效应,进一步评估岩溶区碳循环在全球碳循环的作用和应对气候变化中的地位。

关键词：土壤CO 土壤水分降雨过程岩溶作用减源效应斯洛文尼亚

Ecosystem-driven karst carbon cycle and carbon sink effects

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Journal of Groundwater Science and Engineering 2022年第2期10卷 99-112页

作者： Cheng Zhang Qiong Xiao Ze-yan Wu knez Martin Karst Dynamics Key Laboratory of Ministry of Natural Resources/Guangxi Zhuang Autonomous Region Institute of Karst GeologyChinese Academy of Geological Sciences/International Research Center on Karst Under the Auspices of UNESCOGuilin 541004GuangxiChina Karst Research Institute Slovenian Academy of Sciences and ArtsPostonja弘6230Slovenia

It is recognized that karst processes are actively involved in the current global carbon cycle based on twenty years research,and the carbon sink occurred in karst processes is possibly an important part of“missing sink”in global carbon cycle.In this paper,an overview is given on karst carbon cycle research,and influence factors,formed carbon pools(background carbon sink)and sink increase potentials of current karst carbon cycle are analyzed.Carbonate weathering could contribute to the imbalance item(BIM)and land use change item(ELUC)in the global carbon cycle model,owing to its uptake of both atmospheric CO_(2)(carbon sink effect)and CO_(2) produced by soil respiration(carbon source reduction effect).Karst carbon sink includes inorganic carbon sink resulted from hydrogeochemical process and organic carbon sink generated by aquatic photosynthetic DIC conversion,forming relatively stable river(reservoir)water body or sediment carbon sink.The sizes of both sinks are controlled by terrestrial ecosystems and aquatic ecosystems,respectively.Desertification rehabilitation and carbon sequestration by aquatic plants are two effective ways to increase the carbon sink in karst area.It is estimated that the rate of carbon sink is at least 381000 t CO_(2)/a with vegetation restoration and afforestation in southwest China karst area,while the annual organic carbon sink generated by aquatic photosynthesis is about 84200 t C in the Pearl River Basin.The development of a soil CO_(2) based model for assessment of regional dissolution intensity will help to improve the estimation accuracy of carbon sink increase and potential,thus provide a more clear and efficient karst sink increase scheme and pathway to achieve the goals of“double carbon”.With the deep investigation on karst carbon cycle,mechanism and carbon sink effect,and the improvement of watershed carbon sink measurement methods and regional sink increase evaluation approaches.Karst carbon sink is expected to be included in the list of atmospheric CO_(2) sources/sinks of t

关键词： Karst carbon sink Ecosystem Sink-increase way Carbon pool Rock desertification rehabilitation Aquatic photosynthetic carbon sequestration

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Application of supercritical and subcritical fluids in food processing

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Food Quality and Safety 2018年第2期2卷 59-67页

作者： Maša knez Hrnčič Darija Cör Mojca Tancer Verboten Željko knez Faculty of Chemistry and Chemical Engineering Laboratory for Separation Processes and Product DesignUniversity of MariborSmetanova 17MariborSlovenia Faculty of Law University of MariborMladinska ulica 9MariborSlovenia Faculty of Medicine University of MariborTaborska ulica 8MariborSlovenia

Using high pressure as a processing tool can overcome the legal limitations for solvent residues and restrictions on the use of conventional solvents in chemical processes.Additionally,particulate products can also be achieved by means of supercritical fluid(SCF)processing.This contribution will give a limited overview of applications of subcritical fluid and SCF and will present the energy savings compared with conventional production methods.Considering these qualities,SCFs could certainly be applied as a replacement for conventional solvents in extractive and non-extractive processes,as a nontoxic,inexpensive,non-flammable,and non-polluting solvent.Many applications,such as high pressure sterilization,jet-cutting,thin film deposition for microelectronics,and the separation of value-added products from fermentation broths in the biotechnology field,have been developed on an industrial scale to produce marketable food products.

关键词： separation fractionation extraction value-added products green solvents.

Effects of Selected Printing Parameters on the Fire Properties of 3D-Printed Neat Polylactic Acid(PLA)and Wood/PLA Composites

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Journal of Renewable Materials 2021年第11期9卷 1883-1895页

作者： Nataša knez Mirko Kariž Friderik knez Nadir Ayrilmis Manja Kitek Kuzman Fire Laboratory and Fire Engineering Slovenian National Building and Civil Engineering InstituteLjubljanaSI-1000Slovenia Department of Wood Science and Technology Biotechnical FacultyUniversity of LjubljanaLjubljanaSI-1000Slovenia Department of Wood Mechanics and Technology Forestry FacultyIstanbul University-CerrahpasaIstanbul34473Turkey

The effects of selected printing parameters on the fire properties of additively produced composites from neat polylactic acid(PLA)and wood/PLA filaments were investigated.The reaction to fire of the 3D-printed specimens was tested according to the ISO 5660-1 cone calorimeter test method.The results showed that the properties of the specimens when exposed to fire were significantly affected by the incorporation of wood flour into the PLA filament.It was also interesting that PLA specimens had much better reactions to fire than the wood/PLA specimens.Time to ignition was found to be much longer in the 3D-printed PLA specimens.Although the maximal heat release rate was a little higher in the PLA than the wood/PLA specimens,the duration of HRR was longer for the wood/PLA specimens.The initial mass of the specimens was smaller in the wood/PLA composites,but during the radiant heat exposure the mass typically decreased slower than in the PLA specimens.

关键词： Reaction to fire wood polylactic acid(PLA) filament 3D printer biocomposite

Karren of Mushroom Mountain(Junzi Shan) in the Eastern Yunnan Ridge,Yunnan,China:Karstological and Tourist Attraction

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Acta Geologica Sinica(English Edition) 2010年第2期84卷 424-431页

作者： Martin knez Tadej SLABE Karst Research Institute ZRC SAZU Titov trg 26230 PostojnaSlovenia

Mushroom Mountain karren with predominantly flat tops that formed along the stylolites and bedding planes dictated the special features of this karst landscape. Their features and rock relief clearly reflect the geological conditions and development. The subsoil karren with conical tops dissected by subsoil rock relief were exposed from beneath the soil. Below tree vegetation, the subsoil karren are to a great extent covered by moss and lichen, under which they acquire their characteristic shape. On the bare surface they were reshaped by rainwater that carves flutes and solution pans. The old cave that opens below the top of one of the cones reveals the period before its dissection into hills and cones when this part of the karst aquifer was still deep under the water table.

关键词： karst karren cave rock relief development of karst Shizong Yunnan

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Shilin:The Formation of Stone Forests in Various Rock Types(Lunan,Yunnan,China)

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Acta Geologica Sinica(English Edition) 2007年第1期81卷 148-157页

作者： Martin knez Tadej SLABE Karst Research Institute ZRC SAZU Titov trg 2 6230 Postojna Slovenia

Shilin is among the most interesting form of stone forest to occur in karst landscapes. They develop from karren subsoil, and their shapes, entire forests or just individual pillars and their rock relief, depend on the conditions under which they were formed, their location in the karst landscape, and above all on the characteristics of the rock： its composition, stratification, and fissuring. Because of the exceptional characteristics of this karst phenomenon in China, we propose that the term ＂shilin＂ be used in the professional literature for this type of stone forest.

关键词： Shilin karst surface development rock relief Lunan Yunnan

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Quantum spin Hall effect in inverted InAs/GaSb quantum wells

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Frontiers of physics 2012年第2期7卷 200-207页

作者： Ivan knez (1) Rui-Rui Du (1) 1. Department of Physics and Astronomy Rice University Houston TX 77251-1892 USA

我们向在转换 InAs/GaSb 量井(QW ) 观察量旋转霍尔效果考察最近的试验性的进步。在杂交差距的低温度运输大小显示出重要起源的体积电导率，当长度和在这政体的传导力的宽度依赖证明为螺旋状的边模式的存在的充分证据由刘等求婚了时。[P... 详细信息

我们向在转换 InAs/GaSb 量井(QW ) 观察量旋转霍尔效果考察最近的试验性的进步。在杂交差距的低温度运输大小显示出重要起源的体积电导率，当长度和在这政体的传导力的宽度依赖证明为螺旋状的边模式的存在的充分证据由刘等求婚了时。[Phys。加快。Lett， 2008， 100：236601 ] 。令人惊讶地，尽管有可比较的体积传导，边模式坚持并且在磁场上显示出仅仅弱的依赖。我们阐明体积运输上的边的那表面上的独立在在体积和边之间的费密波浪向量由于不同来，导致边模式的全部的内部思考。

关键词：霍尔效应量子自旋量子阱锑化镓砷化铟散装运输实验进展低温运输

Microstructure evolution and mechanical properties of hot deformed Mg9Al1Zn samples containing a friction stir processed zone

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Journal of Magnesium and Alloys 2017年第4期5卷 388-403页

作者： E.Cerri D.knez T.Rimoldi M.T.Di Giovanni D.I.A.Universitàdi Parma via G.Usberti 181/A43124ParmaItaly FELMI-ZFE Steyrergasse 178010GrazAustria

During the last decade,FSP of magnesium alloys has become more popular due to the potential microstructure refinement of their eutectic phases,and interest has increased around the AZ1 that is one of the most commercially used magnesium alloys.In this work,high pressure die cast AZ91 plates were tensile tested at high temperatures after friction stir processing(FSP),with the stirred region in the middle of the gauge length.Samples deformed at 350℃ revealed an increment of ductility that was doubled as compared to those deformed at 300℃ and a strengthening of the nugget was measured by Vickers microhardness(HV).The correlation of HV average values to local grain size confirmed the validity of the Hall–Petch type equation where stress is replaced by hardness.X-rays diffraction and electrical conductivity highlighted the potential increment of solute atoms in solid solution during FSP.Scanning Electron Microscopy(SEM)and Transmission Electron Microscopy(TEM)investigations performed on as-FSPed and hot deformed samples determined MgAlZn and AlMn particles type evolution through statistical analysis that supported mechanical properties and the strengthening mechanisms.

关键词： AZ91 Friction stir processing Mechanical properties Microstructure SEM TEM

Helium droplet assisted synthesis of plasmonic Ag@ZnO core@shell nanoparticles

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Nano Research 2020年第11期13卷 2979-2986页

作者： Alexander Schiffmann Thomas Jauk Daniel knez Harald Fitzek Ferdinand Hofer Florian Lackner Wolfgang E.Ernst Institute of Experimental Physics Graz University of TechnologyA-8010GrazAustria Institute of Electron Microscopy and Nanoanalysis&Graz Centre for Electron Microscopy Graz University of TechnologyA-8010GrazAustria

Plasmonic Ag@ZnO core@shell nanoparticles are formed by synthesis inside helium droplets with subsequent deposition and controlled oxidation.The particle size and shape can be controlled from spherical sub-10 nm particles to larger elongated structures.An advantage of the method is the complete absence of solvents,precursors,and other chemical agents.The obtained particle morphology and elemental composition have been analyzed by scanning transmission electron microscopy(STEM)and energy dispersive X-ray spectroscopy(EDS).The results reveal that the produced particles form a closed and homogeneous ZnO layer around a 2–3 nm Ag core with a uniform thickness of(1.33±0.15)nm and(1.63±0.31)nm for spherical and wire-like particles,respectively.The results are supported by ultraviolet photoelectron spectroscopy(UPS),which indicates a fully oxidized shell layer for the particles studied by STEM.The plasmonic properties of the produced spherical Ag@ZnO core@shell particles are investigated by two-photon photoelectron(2PPE)spectroscopy.Upon excitation of the localized surface plasmon resonance in Ag at around 3 eV,plasmonic enhancement leads to the liberation of electrons with high kinetic energy.This is observed for both Ag and Ag@ZnO particles,showing that even if a Ag cluster is covered by the ZnO layer,a plasmonic enhancement can be observed by photoelectron spectroscopy.

关键词： nanoparticle helium droplet plasmonics photoelectrons