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mapping groundwater dependent ecosystem potential in a semi-arid environment using aremote sensing-based multiple-lines-of-evidence approach

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International Journal of Digital Earth 2023年第1期16卷 375-406页

作者： Stephen G.Fildes Tanya m.Doody David Bruce ian F.Clark Okke Batelaan UniSA STEm University of South AustraliaAdelaideAustralia CSIRO Land and WaterAdelaideAustralia National Centre for Groundwater Research and Training(NCGRT) College of Science and EngineeringFlinders UniversityBedford ParkAustralia

Groundwater dependent ecosystems(GDEs)are vulnerable to groundwater regime ***,their protection is often hampered by challenges in their *** is presented a remote sensing-based GDE potential mapping approach based on the persistency of relevant vegetation parameters during prolonged dry periods as an indicator of potential‘consistency’of water supply(***).The study uses a novel approach to characterising persistency for selected vegetation parameters based on a normalised difference measure and an adaptation of the coefficient of variation *** of parameters was facilitated through the analytic hierarchy process providing a structured weighting approach to minimise parameter *** approach is demonstrated in the semi-arid Flinders Ranges of South Australia where new groundwater resources are being sought to support local domestic and industry *** in GDE potential were mapped to better target areas where exploration of groundwater should be *** results indicated a high-level of agreement of 77%with an independent springs dataset,along with an 87%agreement with areas coinciding with known phreatophyte species and depths to *** index-based mapping approach has potential applicability across landscapes,as it normalises for variations in vegetation cover,minimises technical overheads,and employs continental-wide remote sensing data-products.

关键词： coefficient of variation NDVI coefficient of variation fractional cover barest Earth wetness percentiles actual evapotranspiration analytic hierarchy process groundwater potential

Zinc, copper, and strontium isotopic variability in the Baiyangping Cu–Pb–Zn–Ag polymetallic ore field, Lanping Basin, Southwest China

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Acta Geochimica 2021年第4期40卷 557-574页

作者： Caixia Feng Shen Liu Guoxiang Chi Xianwu Bi Ruizhong Hu ian mCoulson State Key Laboratory of Continental Dynamics Department of GeologyNorthwest University229 Taibai RoadXi’an 710069China Departments of Geology University of Regina3737 Wascana ParkwayReginaSK S4S 0A2Canada Institute of Geochemistry Chinese Academy of Sciences99 Lincheng RoadGuiyang 550002China

The Baiyangping Cu-Ag polymetallic ore district is located in the northern part of the Lanping-Simao foreland fold belt,between the Jinshajiang-Ailaoshan and Lancangjiang faults,and the deposit can be divided into eastern and western ore *** upon microscope observation of ore minerals and analysis of zinc,copper,and strontium isotope composition,we conclude that:(1)the zinc isotopic compositions of sphalerite from the eastern and western ore belt of the Baiyangping polymetallic ore deposits are enriched in both the heavy(-0.09‰ to+0.15‰) and light(-0.19‰ to-0.01‰)zinc *** fractionation is likely the additional factor controlling the observed temporal and spatial variations in zinc isotopes in the two studied ore *** zinc isotopic composition in the Baiyangping polymetallic Pb-Zn deposits may have the same fractionation as that of magmatic-hydrothermal,VHmS,SEDEX,and mVT deposits,as demonstrated by geological and other geochemical evidence;(2) the range of δ^(65)Cu in massive tetrahedrite is from-0.06‰ to+0.12 ‰ that relates to the early stages of ore-formation,which are higher than that of venial chalcopyrite(from-0.72‰ to-0.07‰)formed at a late ore-forming stage in the western ore *** ore-forming stages and alteration or leaching processes are likely the main factors controlling the observed variations in copper isotopes in the western ore zone;(3) the ^(87)Sr/^(86)Sr value of hydrothermal calcite in eastern(0.7080-0.7093) and western(0.7085-0.7113) ore belt suggested that mineralization of early calcite,with^(87)Sr/^(86)Sr values much higher than in ancient Late Triassic seawater,may be related to recrystallization from a radiogenic Sr-rich or silicifying fluid,either from the strata that the ore-forming fluid flows through or from other fluids.

关键词： Zn-Cu-Sr isotopic variation Cu-Pb-Zn-Ag poly-metallic ore deposit Baiyangping Lanping Basin

Silencing NOA1 Elevates Herbivory-Induced Jasmonic Acid Accumulation and Compromises most of the Carbon-Based Defense metabolites in Nicotiana attenuata

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Journal of Integrative Plant Biology 2011年第8期53卷 619-631页

作者： Hendrik Wünsche ian T. Baldwin Department of molecular Ecology max Planck Institute for Chemical Ecology

Nitric oxide-associated protein 1 （NOA1） is involved in various abiotic stress responses and is required for plant resistance to pathogen infections. However, the role of NOA1 in plant-herbivore interactions has not been explored. We created NOA1-silenced Nicotiana attenuata plants （irNaNOA1）. Compared with wild-type （WT） plants, irNaNOA1 plants had highly decreased photosynthesis rates. We further examined various traits important for plant defense against its specialist herbivore manduca sexta by treating WT and irNaNOA1 plants with mechanical wounding and m. sexta oral secretions （OS）. NOA1-silenced plants showed elevated levels of herbivory-induced jasmonic acid （JA）, but decreased JA-isoleucine conjugate （JA-Ile） levels. The decreased JA-Ile levels did not result from compromised JAR （jasmonic acid resistant） activity in irNOA1 plants. moreover, nitrogen-rich defensive compounds, nicotine and trypsin proteinase inhibitors, did not differ between WT and irNaNOA1 plants. In contrast, concentrations of most carbon-based defensive compounds were lower in these plants than in WT plants, although the levels of chlorogenic acid were not changed. Therefore, silencing NOA1 alters the allocation of carbon resources within the phenylpropanoid pathway. These data suggest the involvement of NOA1 in N. attenuata’s defense against m. sexta attack, and highlight its role in photosynthesis, and biosynthesis of jasmonates and secondary metabolites.

关键词： NOA1 defense herbivory nitric oxide-associated protein 1 secondary metabolites.

Geochronology and Genetic model for Early Cretaceous Volcanic Rocks from the Southern Qiangtang Terrane,Northern Tibet,China: Constraints from U-Pb Zircon Dating, Whole-Rock Geochemical and Sr-Nd Isotopic Data

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2157-2178页

作者： LIU Shen FENG Caixia m.Santosh FENG Guangying XU mengjing ian m.COULSON GUO Xiaolei GUO Zhuang FAN Yan State Key Laboratory of Continental Dynamics and Department of Geology Northwest UniversityXi'an 710069China China University of Geosciences Beijing 100083 BeijingChina Department of Earth Sciences University of AdelaideAdelaide SA 5005Australia Institute of Geology Chinese Academy of Geological Sciences100037 BeijingChina Solid Earth Studies Laboratory Department of GeologyUniversity of ReginaReginaSaskatchewan S4S OA2Canada

Post-collisional volcanic rocks of mesozoic age occur in the regions adjacent to Gerze, part of the southern Qiangtang Terrane of northern Tibet, China. Geochronological, geochemical, and wholerock Sr-Nd isotopic analyses were performed on the volcanic rocks to better characterize their emplacement age and models for their origin. Laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-mS) U-Pb zircon analyses yielded consistent ages ranging from 123.1±0.94 ma to 124.5±0.89 ma for six volcanic rocks from the study area. The intermediate volcanic rocks belong to the alkaline and sub-alkaline magma series in terms of K2 O+Na2 O contents(5.9%–9.0%), and to the shoshonitic and calc-alkaline series on the basis of their high K2 O contents(1.4%–3.3%). The Gerze volcanic rocks are characterized by the enrichment of light rare earth elements [(La/Yb)N=34.9–49.5] and large–ion lithophile elements(e.g., Rb, Ba, Th, U, K, Pb, and Sr), slightly negative Eu anomalies(Eu/Eu*=0.19–0.24), and negative anomalies in high field strength elements(e.g., Nb, Ta, Hf and Ti), relative to primitive mantle. The samples show slightly elevated(87 Sr/86 Sr)i values that range from 0.7049 to 0.7057, and low εNd(t) values from-0.89 to-2.89. These results suggest that the volcanic rocks studied derived from a compositionally heterogeneous mantle source and that their parent magmas were basaltic. The more mafic, parental magmas to the Gerze volcanic rocks likely underwent fractional crystallization of clinopyroxene, hornblende, biotite, and potassium feldspar, during ascent, with little to no crustal contamination, prior to their eruption/emplacement. While these volcanic rocks exhibit geochemical signatures typical of magmas formed in a destructive plate-margin setting, it is plausible that their mantle source might also have acquired such characteristics in an earlier episode of subduction.

关键词： volcanic rock U–Pb age–dating origin Qiangtang Terrane northern Tibet

mantle plume:the dynamic setting of the origin of Early Paleozoic mafic dykes in Ziyang,Shaanxi Province,Southern Qinling Block,China

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Acta Geochimica 2020年第3期39卷 307-325页

作者： Xiaoqing Chen Shen Liu Caixia Feng ian m.Coulson Yan Fan Kairui Tai Tianjing Gao Siyuan Zhang College of Earth Science Jilin UniversityChangchun 130061China State Key Laboratory of Continental Dynamics and Department of Geology Northwest UniversityXi'an 710069China Solid Earth Studies Laboratory Department of GeologyUniversity of ReginaReginaSK S4S 0A2Canada

The mafic dykes(dolerites)during the Early Paleozoic are widely spread in Langao-Ziyang,southern Qiling Block,and the investigation on these dykes are very *** studies have mainly focused on the Silurian mafic dykes;however,research on the Earlier Paleozoic mafic dykes is relatively weak at ***,the overall understanding of the mantle source and genetic dynamic setting during the Early Paleozoic in this area is *** study the accurate age and origin of the Early Paleozoic mafic dykes in Ziyang,southern Shaanxi Province,the mafic dykes from dabacunand Qinmingzhai were selected and the petrology,zircon U-Pb chronology,geochemistry,and Sr-Nd-Hf isotopes were *** indicates that the mafic dykes studied are mainly composed of dolerite,and they are the products of the Early Ordovician(475.8-480.7 ma).Furthermore,the dolerites belong to alkaline rock series,and they are characterized by enrichment in LREE,Rb,Ba,Sr,Nb,(87Sr/86Sr)i=0.7020-0.7050,εNd(t)=3.0-4.0),εHf(t)=4.5-12.1,176Hf/177Hf=*** suggests that the mafic dyke were derived from the partial melting of a depleted lithospheric mantle,and the genetic process is mainly controlled by the mantle plume based on the discussion of the genetic ***,the genetic process experienced the separation and crystallization of olivine and clinopyroxene at the same time,with little crustal contamination.

关键词： Early Paleozoic Dolerites Geochemistry Origin mantle plume

微粒对多晶冰及冰川流变行为的影响——(Ⅰ)基于位错的弛豫模型

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地球物理学报 2007年第1期50卷 126-130页

作者：宋旼 David m.Cole ian Baker 中南大学粉末冶金国家重点实验室 US Army Cold Regions Research and Engineering Laboratory Hanover NH03755U.S.A. Thayer School of Engineering Dartmouth CollegeHanover NH03755U.S.A.

为量化冰及冰川在流变过程中位错密度随流变应力的变化,发展了一个基于位错的非线性弛豫模型.模型的计算表明:在冰的指数蠕变阶段,滞弹性试验所形成的应力/应变滞后环的宽度与面积随流变应力的增加呈线性增加,位错密度随流变应力的增加... 详细信息

为量化冰及冰川在流变过程中位错密度随流变应力的变化,发展了一个基于位错的非线性弛豫模型.模型的计算表明:在冰的指数蠕变阶段,滞弹性试验所形成的应力/应变滞后环的宽度与面积随流变应力的增加呈线性增加,位错密度随流变应力的增加呈平方增加;在冰的线性蠕变阶段,滞弹性试验所形成的应力/应变滞后环的宽度、面积和位错密度保持不变.

关键词：冰与冰川位错弛豫流变非线性模型

The commutant and similarity invariant of analytic Toeplitz operators on Bergman space

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Science China mathematics 2007年第5期50卷 651-664页

作者： Chun-ian JianG Yu-cheng Li Department of mathematics Hebei Normal UniversityShijiazhuang 050016China

The famous von Neumann-Wold Theorem tells us that each analytic Toeplitz operator with n + 1-Blaschke factors is unitary to n + 1 copies of the unilateral shift on the Hardy space. It is obvious that the von Neumann-Wold Theorem does not hold in the Bergman space. In this paper, using the basis constructed by michael and Zhu on the Bergman space we prove that each analytic Toeplitz operator m B(z) is similar to n + 1 copies of the Bergman shift if and only if B(z) is an n + 1-Blaschke product. From the above theorem, we characterize the similarity invariant of some analytic Toeplitz operators by using K 0-group term.

关键词： Bergman space analytic Toeplitz operators invariant subspace commutant similarity invariant K 0-group 32A36 46J40 47A15

Stable isotope analysis of diet confirms niche separation of two sympatric species of Namib Desert lizard

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Integrative Zoology 2016年第1期11卷 60-75页

作者： ian W.mURRAY Hilary m.LEASE Robyn S.HETEm Duncan mITCHELL Andrea FULLER Stephan WOODBORNE Brain Function Research Group School of PhysiologyFaculty of Health SciencesUniversity of the WitwatersrandJohannesburgSouth Africa Biology Department Whitman CollegeWalla WallaWashingtonUSA iThemba Laboratories GautengSouth Africa Stable Isotope Laboratory Mammal Research InstituteDepartment of Zoology and EntomologyUniversity of PretoriaPretoriaSouth Africa

We used stable isotopes of carbon and nitrogen to study the trophic niche of two species of insectivorous lizards,the Husab sand lizard Pedioplanis husabensis and Bradfield’s Namib day gecko living sympatrically in the Namib *** measured theδ13C andδ15N ratios in lizard blood tissues with different turnover times(whole blood,red blood cells and plasma)to investigate lizard diet in different *** also measured theδ13C andδ15N ratios in available arthropod prey and plant tissues on the site,to identify the avenues of nutrient movement between lizards and their *** the use of stable isotope mixing models,we found that the two lizard species relied on a largely non-overlapping but seasonally variable array of arthropods:*** primarily fed on termites,beetles and wasps,while *** fed mainly on ants,wasps and *** originating from C3 plants were proportionally higher for *** than for *** during autumn and late autumn/early winter,although not *** to the few available data estimating the trophic transfer of nutrients in ectotherms in mixed C3 and C4/crassulacean acid metabolism(CAm)plant landscapes,we found that our lizard species primarily acquired nutrients that originated from C4/CAm *** work adds an important dimension to the general lack of studies using stable isotope analyses to estimate lizard niche partitioning and resource use.

关键词： Namib Desert niche partitioning Pedioplanis Rhoptropus stable isotopes

Downscaling Landsat-8 land surface temperature maps in diverse urban landscapes using multivariate adaptive regression splines and very high resolution auxiliary data

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International Journal of Digital Earth 2020年第8期13卷 899-914页

作者： Joanna Zawadzka Ron Corstanje Jim Harris ian Truckell Centre for Environmental and Agricultural Informatics School of WaterEnergy and EnvironmentCranfield UniversityBedfordshireUK

We propose a method for spatial downscaling of Landsat 8-derived LST maps from 100(30 m)resolution down to 2–4 m with the use of the multiple Adaptive Regression Splines(mARS)models coupled with very high resolution auxiliary data derived from hyperspectral aerial imagery and large-scale topographic *** applied the method to four Landsat 8 scenes,two collected in summer and two in winter,for three British towns collectively representing a variety of urban *** used several spectral indices as well as fractional coverage of water and paved surfaces as LST predictors,and applied a novel method for the correction of temporal mismatch between spectral indices derived from aerial and satellite imagery captured at different dates,allowing for the application of the downscaling method for multiple dates without the need for repeating the aerial *** results suggest that the method performed well for the summer dates,achieving RmSE of 1.40–1.83 K prior to and 0.76–1.21 K after correction for *** conclude that the mARS models,by addressing the non-linear relationship of LST at coarse and fine spatial resolutions,can be successfully applied to produce high resolution LST maps suitable for studies of urban thermal environment at local scales.

关键词： Land surface temperature downscaling urban multivariate adaptive regression splines remote sensing