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Fluctuating resources,disturbance and plant strategies:diverse mechanisms underlying plant invasions

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Journal of Arid Land 2013年第3期5卷 284-297页

作者： Ian J RADFORD csiro Sustainable Ecosystems Davies LaboratoryPrivate Mailbag POAitkenvale 4814Australia Botany Department University of OtagoPO Box 56Dunedin 9054New Zealand

This paper examines the hypothesis that non-native plant invasions are related to fluctuating resource availability as proposed by Davis et al. （2000）. I measured relative functional responses of both invasive and native plants to changed resource availability due to nutrient enrichment and rainfall, and to increased disturbance. Data are presented from studies in two contrasting ecosystems. First is a series of glasshouse and field experiments on the invader Hieracium lepidulum and associated invasive and native species in subalpine temperate New Zealand. Second is a field study of invasive and native plant responses to altered disturbance regimes and rainfall from tropical savannas of north eastern Australia. Invaders responded differently from native species to changes in resource availability in both subalpine and tropical studies. However, invaders differed among themselves showing that different species exploit different functional niches to invade their respective habitats. These findings contribute to the contention that the fluctuating resource hypothesis does not provide a universal explanation for plant invasions. The diverse functional responses to increased resource availability among invaders in this and previous studies suggest that the cause of invasion depends on unique combinations of habitat and functional attributes of invaders and native assemblages. Such findings imply that universal predictions of what will happen under climate change scenarios across the globe will be difficult to make.

关键词： plant invasion plant strategies C-S-R triangle fluctuating resources disturbance

An efficient framework for ensemble of natural disaster simulations as a service

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Geoscience Frontiers 2020年第5期11卷 1859-1873页

作者： Ujjwal KC Saurabh Garg James Hilton Discipline of ICT University of TasmaniaHobartAustralia Data61 CSIROMelbourneAustralia

Calculations of risk from natural disasters may require ensembles of hundreds of thousands of simulations to accurately quantify the complex relationships between the outcome of a disaster and its contributing *** large ensembles cannot typically be run on a single computer due to the limited computational resources *** Computing offers an attractive alternative,with an almost unlimited capacity for computation,storage,and network ***,there are no clear mechanisms that define how to implement these complex natural disaster ensembles on the Cloud with minimal time and *** such,this paper proposes a system framework with two phases of cost optimization to run the ensembles as a service over *** cost is minimized through efficient distribution of the simulations among the cost-efficient instances and intelligent choice of the instances based on pricing *** validate the proposed framework using real Cloud environment with real wildfire ensemble scenarios under different user *** experimental results give an edge to the proposed system over the bag-of-task type execution on the Clouds with less cost and better flexibility.

关键词： Wildfire prediction Ensemble simulation Cloud computing Natural disaster models

Strongly seasonal Proterozoic glacial climate in low palaeolatitudes:Radically different climate system on the pre-Ediacaran Earth

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Geoscience Frontiers 2016年第4期7卷 555-571页

作者： George E.Williams Phillip W.Schmidt Grant M.Young Department of Earth Sciences University of AdelaideSA 5005Australia csiro Mineral Resources Flagship PO Box 52North RydeNSW 16FOAustralia Department of Earth Sciences University of Western OntarioLondonOntario N6A 5B7Canada

Proterozoic （pre-Ediacaran） glaciations occurred under strongly seasonal climates near sea level in low palaeolatitudes. Metre-scale primary sand wedges in Cryogenian periglacial deposits are identical to those actively forming, through the infilling of seasonal （winter） thermal contraction-cracks in perma- frost by windblown sand, in present-day polar regions with a mean monthly air temperature range of 40 ~C and mean annual air temperatures of -20 ~C or lower. Varve-like rhythmites with dropstones in Proterozoic glacial successions are consistent with an active seasonal freeze-thaw cycle. The seasonal （annual） oscillation of sea level recorded by tidal rhythmites in Cryogenian glacial successions indicates a significant seasonal cycle and extensive open seas. Palaeomagnetic data determined directly for Prote- rozoic glacial deposits and closely associated rocks indicate low palaeolatitudes： Cryogenian deposits in South Australia accumulated at 〈10% most other Cryogenian deposits at 〈20~ and Palaeoproterozoic deposits at 〈15~ palaeolatitude. Palaeomagnetic data imply that the Proterozoic geomagnetic field approximated a geocentric axial dipole, hence palaeolatitudes represent geographic latitudes. The Cry- ogenian glacial environment included glacier-flee, continental permafrost regions with ground frozen on a kyr time-scale, aeolian sand-sheets, extensive and long-lived open seas, and an active hydrological cycle. This palaeoenvironment confiicts with the ＇snowball Earth＇ and ＇slushball Earth＇ hypotheses, which cannot accommodate large seasonal changes of temperature near the equator. Consequently, their proponents have attempted to refute the evidence for strong seasonality by introducing Popperian ＇auxiliary assumptions＇. However, non-actualistic arguments that the Cryogenian sand wedges indicate diurnal or weakly seasonal temperature changes are based on misunderstandings of periglacial pro- cesses. Modelling of a strongly seasonal climate for a frozen-over Ear

关键词： Proterozoic Glaciation Periglacial structures Varves Paleoclimate Paleomagetism

Integrated real-time roof monitoring

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Journal of Coal Science & Engineering(China) 2009年第3期15卷 313-317页

作者： SHEN Bao-tang GUO Hua KING Andrew csiro Exploration and Mining Kenmore QLD4069 Australia

csiro has recently developed a real-time roof monitoring system for under-groundcoal mines and successfully tried the system in gate roads at Ulan *** systemintegrated displacement monitoring,stress monitoring and seismic monitoring in *** included GEL multianchor extensometers,vibrating wire uniaxial stress meters,ESG seismic monitoring system with microseismic sensors and high-frequency AE *** monitoring system automated and the data can be automatically collected by acentral computer located in an underground nonhazardous *** data are then transferredto the surface via an optical fiber *** real-time data were accessed at anylocation with an Internet *** trials of the system in two tailgates at Ulan Minedemonstrate that the system is effective for monitoring the behavior and stability of roadwaysduring Iongwall *** continuous roof displacement/stress data show clearprecursors of roof *** seismic data (event count and locations) provide insights intothe roof failure process during roof fall.

关键词：实时监测系统屋顶地震监测系统声发射传感器自动监测系统应力监测互联网连接地下煤矿

Evapotranspiration estimation methods in hydrological models

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Journal of Geographical Sciences 2013年第2期23卷 359-369页

作者： ZHAO Lingling XIA Jun XU Chong-yu WANG Zhonggen SOBKOWIAKLeszek LONG Cangrui KeyLaboratoryofWaterCycle&RelatedLandSurfaceProcesses.InstituteofGeographicSciencesandNaturalResourcesReseamh GASBeijing100101China GraduateUniversityofChineseAcademyofSciences Beijing100049China StateKeyLab.ofWaterResources&HydropowerEngineeringScience WuhanUniversityWuhan430072China DepartmentofGeosciences UniversityofOsloOsloNorway DepartmentofHydrologyandWaterManagement InstituteofPhysicalGeogmphyandEnvironmentalPlanningAdamMickiewiczUniversityPoznanPoland PuyangWaterConservancyBureau Puyang457000HenanChina

Actual evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance and land surface energy balance. Evapotranspiration plays a key role in simulating hydrological effect of climate change, and a review of evapotranspiration estimation methods in hydrological models is of vital importance. This paper firstly summarizes the evapotranspiration estimation methods applied in hydrological models and then classifies them into the integrated converting methods and the classification gathering methods by their mechanism. Integrated converting methods are usually used in hydrological models and two differences exist among them： one is in the potential evaporation estimation methods, while the other in the function for defining relationship between potential evapora tion and actual evapotranspiration. Due to the higher information requirements of the Pen- man-Monteith method and the existing data uncertainty, simplified empirical methods for calculating potential and actual evapotranspiration are widely used in hydrological models. Different evapotranspiration calculation methods are used depending on the complexity of the hydrological model, and importance and difficulty in the selection of the most suitable evapotranspiration methods is discussed. Finally, this paper points out the prospective de velopment trends of the evapotranspiration estimating methods in hydrological modeling.

关键词： hydrological model actual evaporation potential evaporation function of soil moisture

In situ small angle X-ray scattering investigation of the thermal expansion and related structural information of carbon nanotube composites

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Progress in Natural Science:Materials International 2012年第6期22卷 673-683页

作者： Ludovic Dumee Aaron Thornton Kallista Sears Jurg Schütz Niall Finn Steven Spoljaric Robert Shanks Chris Skourtis Mikel Duke Stephen Gray Institute for Frontier Materials Deakin UniversityPigdons Road-Waurn Ponds campusGeelongVIC 3216-Australia Institute for Sustainability and Innovation Victoria UniversityHoppers CrossingVIC 3029-Australia csiro Materials Science and Engineering ClaytonVIC 3108-Australia Department of Biotechnology and Chemical Technology.Aalto University School of Chemical Technology.Aalto Espoo.Finland School of Applied Sciences RMIT UniversityLa Trobe St.MelbourneVIC 3000Australia School of Engineering and Science Victoria University.Hoppers Crossing.VIC 3029-Australia

In-sim thermal expansion tests on a series of carbon nanotube bucky-paper composites were performed with direct heating within a synchrotron SAXS *** impact of the samples density and morphology as well as the chemistry and degree of decoration of the carbon nanotubes on the scattering patterns were investigated and correlated to the materials *** results demonstrate that simple densification techniques,such as acetone dipping or gold electroless deposition,could reduce greatly the displacements of the carbon nanotubes within the structure and lead to more thermally stable material.

关键词： Carbon nanotube composites Thermal expansion bucky-paper Small angle X-ray scattering Carbon nanotube densification

The stability of inorganic perovskite solar cells:from materials to devices

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Materials Futures 2023年第3期2卷 21-37页

作者： Bingcheng Yu Shan Tan Dongmei Li Qingbo Meng Beijing National Laboratory for Condensed Matter Physics Renewable Energy LaboratoryInstitute of PhysicsChinese Academy of Sciences(CAS)Beijing 100190People’s Republic of China Huairou Division Institute of PhysicsChinese Academy of SciencesBeijing 101407People’s Republic of China College of Materials Science and Opto-Electronic Technology University Chinese Academy of SciencesBeijing 100049People’s Republic of China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Songshan Lake Materials Laboratory DongguanGuangdong 523808People’s Republic of China

Inorganic halide perovskite solar cells(IHPSCs)have become one of the most promising research hotspots due to to the excellent light and thermal stabilities of inorganic halide perovskites(IHPs).Despite rapid progress in cell performance in very recent years,the phase instability of IHPs easily occurs,which will remarkably influence the cell efficiency and *** effort has been devoted to solving this *** this review,we focus on representative progress in the stability from IHPs to IHPSCs,including(i)a brief introduction of inorganic perovskite materials and devices,(ii)some new additives and fabrication methods,(iii)thermal and light stabilities,(iv)tailoring phase stability,(v)optimization of the stability of inorganic perovskite solar cells and(vi)interfacial engineering for stability ***,perspectives will be given regarding future work on highly efficient and stable *** review aims to provide a thorough understanding of the key influential factors on the stability of materials to highly efficient and stable IHPSCs.

关键词： inorganic halide perovskites inorganic halide perovskite solar cells light stability thermal stability phase instability

Collection,curation and the use of humidification to restore nest shape in a research museum bird nest collection

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Avian Research 2021年第3期12卷 399-411页

作者： Tonya M.Haff Natalie Tees Kathryn Wood E.Margaret Cawsey Leo Joseph Clare E.Holleley Australian National Wildlife Collection National Research Collections AustraliaCSIROGPO Box 1700CanberraACT 2601Australia

Background:Bird nests are an important part of avian *** are a powerful tool for studying not only the birds that built them,but a wide array of topics ranging from parasitology,urbanisation and climate change to *** this,bird nests tend to be underrepresented in natural history collections,a problem that should be redressed through renewed focus by collecting ***:Here we outline the history and current best practice collection and curatorial methods for the nest col-lection of the Australian National Wildlife Collection(ANWC).We also describe an experiment conducted on nests in the ANWC using ultrasonic humidification to restore the shape of nests damaged by inappropriate ***:The experiment showed that damaged nests can be successfully reshaped to close to their original ***,restored nests were significantly closer to their original shape than they were prior to ***,even nests damaged by years of neglect may be fully incorporated into active research *** practice techniques include extensive note taking and photography in the field,subsampling of nests that cannot or should not be collected,appropriate field storage,metadata management,and prompt treatment upon arrival at the collec-tion ***:Renewed focus on nest collections should include appropriate care and restoration of current col-lections,as well as expansion to redress past *** could include collaboration with researchers studying or monitoring avian nesting ecology,and nest collection after use in bird species that rebuild anew each nesting *** expansion of museum nest collections will allow researchers and natural history collections to fully realise the scientific potential of these complex and beautiful specimens.

关键词： Best practice Bird Curation Nest Nest shape Natural history collection Humidification Object restoration Preservation

K-Ar Dating of Authigenic Illites and Its Applications to the Study of Hydrocarbon Charging Histories of Typical Sandstone Reservoirs in Tarim Basin, China

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Petroleum Science 2005年第2期2卷 12-24,81页

作者： ZhangYouyu HorstZwingmann AndrewTodd LiuKeyu LuoXiuquan ResearchInstituteofPetroleumExplorationandDevelopment（RIPED） Beijing100083China／／KeyLaboratoryforHydrocarbonReservoirsChinaNationalPetroleumCorporation（CNPC）Beijing100083China csiroPetroleumResources POBox1130BentleyWA6102Australia ResearchInstituteofPetroleumExplorationandDevelopment（RIPED） Beijing100083China

The Tarim Basin in China comprises eight sets of sandstone reservoirs, five of which are investigated in detail in this study. The main purpose of this study is to investigate the hydrocarbon charging histories of reservoirs by applying K-Ar dating of authigenic illites. The ages of authigenic illites from the Lower Silurian bituminous sandstones in the Central Uplift area range from 383.5 to 235.2 Ma, suggesting that the Silurian oil accumulations were formed from the late Caledonian till the late Hercynian. The ages of authigenic illites from the Upper Devonian Donghe Sandstone reservoirs range from 263.8 to 231.3 Ma, indicating that hydrocarbon accumulations within the Donghe sandstone were formed mainly in the late Hercynian. The authigenic illites ages from the Lower Jurassic Yangxia Group sandstones in the Yinan-2 gas reservoir (Yinan-2, Kuqa Depression) range from 28.1 to 23.9 Ma, suggesting that the initial hydrocarbon charging occurred in the Miocene. The ages of the authigenic illites from the Lower Cretaceous sandstones in the Akemomu gas field (Ake-1, Kashi Sag, Southwest Depression) range from 22.6 to 18.8 Ma, indicating a probable early oil accumulation or early migration of hydrocarbon within this area. The illites from the Paleogene sandstones in the Dina-2 gas reservoir (Dina-201, Kuqa Depression) have a detrital origin; they cannot be used to study the hydrocarbon charging histories. The ages of authigenic illites in the underlying Cretaceous sandstones in the same well (Dina-201) range from 25.5 to 15.5 Ma, indicating that hydrocarbon charging in this reservoir probably occurred within the Miocene. This study highlights the potential of applying K-Ar dating of authigenic illites to investigate the timing of hydrocarbon charging histories of the Tarim Basin reservoir sandstones.

关键词： K-Ar dating authigenic illite hydrocarbon charge sandstone reservoirs Tarim Basin