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Hydraulic properties and drought response of a tropical bamboo (Cephalostachyum pergracile)

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Plant Diversity 2024年第3期46卷 406-415页

作者： Wanwalee Kongjarat Lu Han Amy Ny Aina Aritsara Shu-bin Zhang Gao-Juan Zhao Yong-Jiang Zhang Phisamai Maenpuen Ying-Mei Li Yi-Ke Zou Ming-Yi Li Xue-Nan Li lian-bin Tao Ya-Jun Chen CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnan 666303China University of the Chinese Academy of Sciences Beijing 100049China T-STAR Core Team Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnan 666303China School of Biology and Ecology University of MaineOronoMEUSA Climate Change Institute University of MaineOronoME 04469USA School of Biological and Chemical Science Pu’er UniversityXueyuan RoadYunnan 665000China Institute of Ecology and Geobotany School of Ecology and Environmental SciencesYunnan UniversityKunmingYunnan 650091China School of Ecology and Environment Southwest Forestry UniversityKunmingYunnan 650224China Yuanjiang Savanna Ecosystem Research Station Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYuanjiangYunnan 653300China

Bamboo plants are an essential component of tropical ecosystems,yet their vulnerability to climate extremes,such as drought,is poorly understood due to limited knowledge of their hydraulic properties.Cephalostachyum pergracile,a commonly used tropical bamboo species,exhibited a substantially higher mortality rate than other co-occurring bamboos during a severe drought event in 2019,but the underlying mechanisms remain unclear.This study investigated the leaf and stem hydraulic traits related to drought responses,including leaf-stem embolism resistance(P50leaf;P50stem) estimated using optical and X-ray microtomography methods,leaf pressure-volume and water-releasing curves.Additionally,we investigated the seasonal water potentials,native embolism level(PLC) and xylem water source using stable isotope.We found that C.pergracile exhibited strong resistance to embolism,showing low P50leaf,P50stem,and turgor loss point,despite its rapid leaf water loss.Interestingly,its leaves displayed greater resistance to embolism than its stem,suggesting a lack of effective hydraulic vulnerability segmentation(HVS) to protect the stem from excessive xylem tension.During the dry season,approximately 49% of the water was absorbed from the upper 20-cm-deep soil layer.Consequently,significant diurnal variation in leaf water potentials and an increase in midday PLC from 5.87±2.33% in the wet season to 12.87±4.09%in the dry season were observed.In summary,this study demonstrated that the rapid leaf water loss,high reliance on surface water,and a lack of effective HVS in C.pergracile accelerated water depletion and increased xylem embolism even in the typical dry season,which may explain its high mortality rate during extreme drought events in 2019.

关键词： Climate change Drought Hydraulic safety Hydraulic vulnerability segmentation Stable isotope Tree mortality

Weathering of phosphorus-bearing mineral powder and calcium phosphate by Aspergillus niger

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Chinese Journal Of Geochemistry 2012年第4期31卷 390-397页

作者： QIU Shuangshuang lian bin State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China Graduate University of Chinese Academy of Sciences Beijing 100049China

The weathering of phosphorus-bearing mineral powder(PBMP) and calcium phosphate(CP) by Aspergillus niger was compared,and the mechanism involved was analyzed for the comprehensive utilization of PBMP.The concentration of water-soluble phosphorus(WSP),Mg2+,and Ca2+at different culture times,microstructures of particles,and mineral compositions was examined by ultraviolet-visible spectrometer(UV),atomic absorption spectrometry(AAS),scanning electron microscopy(SEM),and X-ray diffraction(XRD).Results showed that the change in the concentrations of WSP,Mg2+,and Ca2+were related to the growth of A.niger and the different mineral compositions.Compared with CP,PBMP was weathered harder by fungi.Traces of the weathered mineral were found through SEM.CP not only showed traces of erosion damage but also appeared as a rhombohedron-like substance.The XRD test indicated that the weathering minerals can form water calcium oxalate.Further analysis revealed that the mechanism of PBMP and CP weathering by A.niger was the collaborative result of mycelium biomechanical effects and the acid-soluble role of acidic metabolites.The phosphorus dissolution rate of PBMP after 20 d was 46.83%,whereas that of CP after 12 d was 91.01%.The findings of this study are significant to the effective use of waste PBMP and to the exploitation of low-grade phosphate rock resources.

关键词：磷酸钙磷矿物黑曲霉紫外可见分光光度计原子吸收光谱仪 XRD测试老化 X-射线衍射

Interactions between Bacillus mucilaginosus and silicate minerals(weathered adamellite and feldspar):Weathering rate,products,and reaction mechanisms

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Chinese Journal Of Geochemistry 2011年第2期30卷 187-192页

作者： Mo, binbin lian, bin State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Bacillus mucilaginosus is a common soil bacterium,and usually used as a model bacterium in studying microbe-mineral interactions.Several reaction mechanisms of B.mucilaginosus weathering silicate minerals were proposed.However,the molecule mechanisms and detailed processes were still unclear.In this paper,bacterium-mineral interactions were studied in terms of variations in pH value over the experimental period,variations in mineral composition,weathering rates of silicate minerals and volatile metabolites in the culture medium,etc.,to further explore the bacterium-mineral interaction mechanisms.The results showed that B.mucilaginosus could enhance silicate mineral weathering obviously.The weathering rates were quite different for various kinds of silicate minerals,and the weathering rate of weathered adamellite could reach 150 mg/m2/d.Although B.mucilaginosus produced little acidic substance,pH in the microenvironment of bacterium-mineral complex might be far lower than that of the circumjacent environment;a large amount of acetic acid was found in the metabolites,and was likely to play an important role as a ligand.These results appear to suggest that acidolysis and ligand degradation are the main mechanisms of B.mucilaginosus dissolving silicate minerals,the formation of bacterium-mineral complexes is the necessary condition for the bacteria weathering silicate minerals,and extracelluar polysaccharides played important roles in bacterium-mineral interaction processes by forming bacterium-mineral complexes and maintaining the spe-cial physicochemical properties of microenvironment.

关键词： Bacillus mucilaginosus silicate mineral interaction weathering rate mechanism

Nitrogen cycle model of agroecosystem in the karst region of Guizhou Province

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Chinese Journal Of Geochemistry 2010年第4期29卷 464-470页

作者： CHEN Ye lian bin School of Chemistry and Chemical Engineering Guizhou University Guiyang 550003 China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

According to the transport theory of soil solutes and the conditions of soil,geology and climate in the karst region of Guizhou Province,a numerical simulation model of edaphic nitrogen element transport under field conditions is initially established.In this model,NO-3 and NH+4 are regarded as soil solutes.Transformation mechanisms such as biological release,bio-immobilization,ammonium adsorption-desorption,nitration-denitrification and factors of crop root uptaking are considered in this model.It is hoped that the data from this model could directly be used to guide agricultural production in this region and offer feasible ways to improve the use of nitrogen element,sustainable development of agriculture in karst mountainous areas and natural environment.

关键词：生态系统模型农业生产贵州省喀斯特地区土壤溶质运移氮循环农业可持续发展反硝化作用

Effect of Bacillus mucilaginosus on weathering of phosphorite and a preliminary analysis of bacterial proteins

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Chinese Journal Of Geochemistry 2008年第2期27卷 209-216页

作者： CHEN Shu lian bin LIU Congqiang The State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

The authors investigated the effect of Bacillus mucilaginosus on weathering of phosphorite. Analysis of different proteins was of significance in exploring the molecular biological mechanism in the bacterial weathering process. The concrete methods are described as follows: Mineral powder was put into liquid culture medium and B. mucilaginosus was incubated in the medium. The control (group) had no mineral powder in the medium. The treatments and controls were cultured simultaneously under the same condition. In a few days, the supernatant was filtrated, the main cations (Ca2+, Mg2+, Na+, Mn2+, Al3+, Fe3+, K+) were measured by ICP-OES, and the contents of water soluble phosphorus (Pws) and silicon (Siws) were determined by colorimetry. The residual solid was weighed on the filter paper, followed by digestion with concentrated HNO3. The concentrations of the main cations and Pws, Siws in the digest liquid were measured by using the method mentioned above. After the supernatant was centrifuged, the precipitation was used to analyze the protein differences between the treatment groups and the control groups by 2-dimentional gel electrophoresis (2-DE). The experimental results showed that apatite and quartz were partially weathered, but kaolinite was dissolved completely. The population of bacteria increased when mineral powder was added in the liquid medium. Software analysis and comparison of the 2-DE pictures of bacterial proteins revealed 1134 visible protein spots in the treatment group, and 729 visible protein spots in the control group. To compare the bacterial protein expression contents of the treatment group with those of the control group, there were 496 different protein spots, including 214 protein spots which indicated that the protein contents increased, 75 protein spots were indicative of a decrease, and 207 proteins were newly synthesized. It is proposed that the increased bacterial contents may be related to some protein expression and activation after the input of mineral powder. Newly synthesized

关键词：磷矿杆菌风化作用蛋白质

Design and application of the method for isolating magnetotactic bacteria

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Chinese Journal Of Geochemistry 2007年第3期26卷 252-258页

作者： XIAO Zhijie lian bin CHEN Jun H. Henry Teng Jiangsu Key Laboratory for Biodlverslty and Blotechnology College of Biologlcal Sciences Nanjing Normal University Nanjing 210097 China Institute of Surficial Geochemistry. Department of Earth Sciences Nanjing University Nanjing 210093 China Department of Chemlstry the George Washington University Washington DC 20052. USA

A simple apparatus was designed to effectively isolate magnetotactic bacteria from soils or sediments based on their magnetotaxis. Through a series of processes including sample incubation, MTB harvesting, isolation, purification and identification, several strains of bacteria were isolated from the samples successfully. By Transmission Electron Microscopy (TEM) and Energy-Dispersive X-ray Analysis (EDXA), these bacteria were certificated to be magnetotactic bacteria. The phylogenetic relationship between the isolated magnetic strains and some known magnetotactic bacteria was inferred by the construction of phylogenetic tree based on 16SrDNA sequences. This apparatus has been proven to have the advantages of being inexpensive, simple to assemble, easy to perform and highly efficient to isolate novel magnetotactic bacteria. The research indicated that the combined approach of harvesting MTB by home-made apparatus and the method of plate colony isolation could purify and isolate magnetotactic bacteria effectively.

关键词：趋磁性隔离带器械化学成分

Ecological effects of the microbial weathering of silicate minerals

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 150-152页

作者： lian bin XIAO Leilei SUN Qibiao College of Life Sciences Nanjing Normal UniversityNanjingJiangsu 210023

1 Introduction Global climate change is one of the greatest challenges facing humankind in the 21st century.Studying,and utilising,the carbon sink caused by the weathering of silicate minerals has been a key research ... 详细信息

关键词： CA Wang CO gene Ecological effects of the microbial weathering of silicate minerals

Zeolite and fungi’s flocculability of simulated wastewater containing heavy metal ions or phosphorus

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Chinese Journal Of Geochemistry 2010年第2期29卷 137-142页

作者： CAO Wenchuan HAO Jianchao lian bin LIU Congqiang WU Fengchang State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002. China Graduate University of the Chinese Academy of Sciences Beo＇ing 10049 China Key Laboratory of Water Environment and Water Resources Tianjin Normal University Tianjin 300387 China Chinese Research Academy of Environmental Sciences Beijing 100012 China Department of Agronomy Tianfin Agricultural University Tianjin 300387 China

This paper focuses on the flocculability of simulated wastewater containing heavy metal ions (Fe3+, Cd2+) or phosphorus by zeolite, microbial flocculants (MBF) produced by Aspergillus niger and the composite flocculant composed of zeolite and MBF. The main results are presented as follows: zeolite was a good flocculant when the contamination of the three simulated wastewaters was low, but the treated water is of turbidness and the particles in it are hard to precipitate. The MBF have a good flocculability toward Fe3+ wastewater, as well as particulate matter. Significant changes in flocculability occurred after adding the composite flocculant in different simulated wastewa-ters, the best or least effect respective for Fe3+ and Cd2+ wastewater. The research we have done shows that the method by which the composite flocculant is used to treat the wastewater containing heavy metal ions or phosphorus provides important reference value for practical application.

关键词：含重金属离子废水模拟废水水絮凝沸石复合絮凝剂磷真菌微生物絮凝剂

中国仲裁机构的功能定位——以优化营商环境的对外吸引力为视角

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上海对外经贸大学学报 2024年第1期31卷 68-78,109页

作者：宋连斌武振国中国政法大学国际法学院北京100088

为了维护内外公平的营商环境,国际同行普遍认为,仲裁活动的中心应是由当事人出资聘请并基于多样化考虑所选择的仲裁庭,由当地出资设立的仲裁机构只具有私行政功能。但在中国,仲裁机构类似法院,被赋予了决定仲裁管辖权、确定裁决籍属、... 详细信息

为了维护内外公平的营商环境,国际同行普遍认为,仲裁活动的中心应是由当事人出资聘请并基于多样化考虑所选择的仲裁庭,由当地出资设立的仲裁机构只具有私行政功能。但在中国,仲裁机构类似法院,被赋予了决定仲裁管辖权、确定裁决籍属、查明外国法以及批准仲裁裁决等四项准司法功能。这些准司法功能肯定了带有属地色彩的仲裁机构对仲裁裁决的控制力,但有可能使得境外投资者担心其在仲裁案件中的利益无法得到公平保护,进而危及营商环境的对外吸引力。为了打消境外投资者的顾虑,仲裁机构不宜行使准司法功能,只应保留私行政功能。

关键词：仲裁机构营商环境准司法功能私行政功能