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Comparison of the influences of vegetation stem parameters on hydraulic variables and sediment transport capacity

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International Soil and Water Conservation Research 2023年第1期11卷 135-144页

作者： Hongli Mu Suhua Fu Department of Geography and Spatial Information Techniques Center for Land and Marine Spatial Utilization and Govemance ResearchNingbo UniversityNingbo315211PR China Bejing Key Laboratoryof Evironmental Remote Sensingand Dgital Cities Facultyof Gegraphical Scence Beijing Nomal UniversityBejing1000875 China

The hydraulic variables(Hv)and sediment transport capacity(Tc)of overland flow have changed immensely due to large-scale ***,research comparing the influences of stem pa-rameters(diameter,cover,and arrangement)on Hv and Tc is *** objectives of this study were to explore and compare the influences of stem parameters on Hv and *** on three treatment groups with varying stem diameters,covers,arrangements,flow discharges and slopes were collected in this *** increasing stem diameter,Hv and Tc increased;Hv included the Reynolds and Froude numbers,flow velocity(v),shear stress(τ),stream power(Ω),and unit stream power(ω).However,the trend of the Darcy-Weisbach friction coefficient(f)was *** and Tc were significantly influenced by stem diameter and *** effect of stem diameter on Hv and Tc was greater than the effects of cover and *** cover as a variable could not be used to adequately estimate the Tc when there were various stem diameters.A new exponential equation involving stem cover and stem diameter was demonstrated to be an appropriate predictor of *** diameter and arrangement had no obvious influence on the relationship between Tc and v,and v as an indicator could explain the effect of stem parameters on Hv and *** result could illustrate why the variables,including v,were able to predict Tc under vegetation stem and litter cover.

关键词： Hydraulic variables Stem arrangement Stem cover Stem diameter Transport capacity

Possible γ-ray emission of radio intermediate AGN Ⅲ Zw 2 and its implication on the evolution of jets in AGNs

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Research in Astronomy and Astrophysics 2010年第8期10卷 707-712页

作者： Liang Chen Jin-Ming Bai Jin Zhang Hong-Tao Liu National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China College of Physics and Electronic Engineering Guangxi Teachers Education University Nanning 530001 China

AGNs with hard γ-ray emission identified so far are radio-loud. Ⅲ Zw 2 is a radio intermediate AGN with a relativistic jet. We study its spectral energy distribution （SED） and find that the broad band emissions are dominated by the nonthermal emissions from the jet. We model its SED through a synchrotron ＋ inverse Compton （IC） model. The results show that the IC component of Ⅲ Zw 2 peaks at a few MeV, and the flux density drops rapidly at higher energy with photon index F 3.3 above 0.1 GeV. The predicted flux is slightly over the sensitivity of Fermi/LAT, but it was not included in the first Fermi/LAT AGN catalog. The reason for this may be： 1） that the IC peak is low and the spectrum is very steep above 0.1 GeV, 2） that Ⅲ Zw 2 is in the low state during the period of the Fermi/LAT operation. We also find that Ⅲ Zw 2 follows similar jet processes as those in γ-ray AGNs, e.g., the relation between jet power and radiation power, which is called the blazar sequence. We suggest that Ⅲ Zw 2 may be a young source at an earlier stage of jet activity.

关键词： galaxies active -- galaxies Seyfert- galaxies jets -- radiation mechanisms non-thermal

Correcting for the solar wind in pulsar timing observations: the role of simultaneous and low-frequency observations

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Research in Astronomy and Astrophysics 2017年第10期17卷 33-40页

作者： Ze-Xi Niu George Hobbs Jing-Bo Wang Shi Dai Department of Astronomy Beijing Normal University Australia Telescope National Facility CSIRO Xinjiang Astronomical Observatory Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences

The primary goal of pulsar timing array projects is to detect ultra-low-frequency gravitational waves. Pulsar data sets are affected by numerous noise processes including varying dispersive delays in the interstellar medium and from the solar wind. The solar wind can lead to rapidly changing variations that, with existing telescopes, can be hard to measure and then remove. In this paper we study the possibility of using a low frequency telescope to aid in such correction for the Parkes Pulsar Timing Array （PPTA） and also discuss whether the ultra-wide-bandwidth receiver for the FAST telescope is sufficient to model solar wind variations. Our key result is that a single wide-bandwidth receiver can be used to model and remove the effect of the solar wind. However, for pulsars that pass close to the Sun such as PSR J1022＋ 1022, the solar wind is so variable that observations at two telescopes separated by a day are insufficient to correct the solar wind effect.

关键词： stars: pulsars -- gravitational waves

Nitrogen addition mediates the response of foliar stoichiometry to phosphorus addition: a meta-analysis

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Ecological Processes 2021年第1期10卷 804-816页

作者： Chengming You Changhui Peng Zhenfeng Xu Yang Liu Li Zhang Rui Yin Lin Liu Han Li Lixia Wang Sining Liu Bo Tan Paul Kardol Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province and National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River and Rainy Area of west china Plantation Ecosystem Permanent Scientifc Research Base Institute of Ecology and ForestrySichuan Agricultural University211 Huimin RoadWenjiang DistrictChengdu 611130SichuanPeople’s Republic of China. Department of Biological Science Institute of Environment SciencesUniversity of Quebec at MontrealCase Postale 8888Succursale Centre-VilleMontrealQC H3C 3P8Canada. Laboratory for Ecological Forecasting and Global Change College of ForestryNorthwest A&F UniversityNo.3 Taicheng RoadYangling 712100People’s Republic of China. Department of Community Ecology Helmholtz-Centre for Environmental Research-UFZTheodor-Lieser-Strasse 406110 HalleSaaleGermany. College of Animal Science and Technology Sichuan Agricultural UniversityChengdu 611130People’s Republic of China. Department of Forest Ecology and Management Swedish University of Agricultural Science90183 UmeåSweden.

Background:Changes in foliar nitrogen(N)and phosphorus(P)stoichiometry play important roles in predicting the efects of global change on ecosystem structure and ***,there is substantial debate on the efects of P addition on foliar N and P stoichiometry,particularly under diferent levels of N ***,we conducted a global meta-analysis to investigate how N addition alters the efects of P addition on foliar N and P stoichiometry across different rates and durations of P addition and plant growth types based on more than 1150 ***:We found that P addition without N addition increased foliar N concentrations,whereas P addition with N addition had no *** positive efects of P addition on foliar P concentrations were greater without N addition than with N ***,the efects of P addition on foliar N,P and N:P ratios varied with the rate and duration of P *** particular,short-term or low-dose P addition with and without N addition increased foliar N concentration,and the positive efects of short-term or low-dose P addition on foliar P concentrations were greater without N addition than with N *** responses of foliar N and P stoichiometry of evergreen plants to P addition were greater without N addition than with N ***,regardless of N addition,soil P availability was more efective than P resorption efciency in predicting the changes in foliar N and P stoichiometry in response to P ***:Our results highlight that increasing N deposition might alter the response of foliar N and P stoichiometry to P addition and demonstrate the important efect of the experimental environment on the *** results advance our understanding of the response of plant nutrient use efciency to P addition with increasing N deposition.

关键词： Ecological stoichiometry Plant nutrient regime Nutrient resorption efciency Soil N and P availability Global change Global synthesis

Taxonomic Revision of Raorchestes menglaensis(Kou,1990)(Amphibia:Anura),with Descriptions of Two New Species from Yunnan,china

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Asian Herpetological Research 2020年第4期11卷 263-281页

作者： Ke JIANG Jinlong REN Jian WANG Junfeng GUO Zeng WANG Yonghong LIU Dechun JIANG Jiatang LI cas Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041SichuanChina Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesYezinNay Pyi Taw 05282Myanmar College of Life Science and Technology Honghe UniversityMengzi 661199YunnanChina Xishuangbanna Tropical Botanical Garden Chinese Academy of SciencesXishuangbanna 666303YunnanChina University of Chinese Academy of Sciences Beijing 100049China cas Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunming 650223YunnanChina

Raorchestes is a group of Bush frogs mainly distributed in South and Southeast Asia that are poorly recognized by morphological *** recognize the true ***(Kou) based on 10 specimens newly collected from the type *** expanded description is also provided,and we delist the recently reported record,***(Boulenger) from *** with morphological and molecular data,two new species are respectively described from Menghai and Lvchun,Yunnan,*** hillisi *** distinguished from all other congeners by the following combination of morphological characters:(1) small body sized(males 15.9-17.7 mm,n=7;female 17.5 mm,n=1);(2) head longer than wide;(3) snout longer than eye diameter;(4) the tip of upper jaws slightly notched;(5) internasal space slightly less than interorbital space;(6) tympanum distinct;(7)fingers lacking lateral dermal fringe;(8) outside of toe Ⅰ and both sides of toe Ⅱ lacking lateral dermal fringe,other toes having weak lateral dermal fringes;(9) rudimentary web on toes;(10) lacking a series of tubercles along the outer sides of forearm and foot;(11) discs of fingers and toes not *** huanglianshan *** distinguished from all other congeners by the following combination of morphological characters:(1) small body size(males 17.0-19.6 mm,n=12;female 21.5 mm,n=1);(2) head slightly wider than long or equal;(3) snout longer than eye diameter;(4)the tip of upper jaws slightly notched;(5) internasal space distinctly less than interorbital space(6) tympanum distinct;(7) fingers lacking lateral dermal fringe;(8) toes lacking lateral dermal fringe;(9) rudimentary web on toes;(10)lacking a series of tubercles along the outer sides of forearm and foot;(11) discs of all fingers and toes orange or parts of them orange in life.

关键词： bush frog distribution Raorchestes hillisi sp.nov. Raorchestes huanglianshan sp.nov. Raorchestes parvulus revision taxonomy

An adaptive loop gain selection for CLEAN deconvolution algorithm

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Research in Astronomy and Astrophysics 2019年第6期19卷 37-42页

作者： Li Zhang Long Xu Ming Zhang Zhong-Zu Wu College of Big Data and Information Engineering Guizhou University Guiyang 550025 China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi 830011 China Key Laboratory of Radio Astronomy Chinese Academy of Sciences Urumqi 830011 China College of Physics Guizhou University Guiyang 550025 China

Radio interferometry significantly improves the resolution of observed images, and the final result also relies heavily on data recovery. The Cotton-Schwab CLEAN(CS-Clean) deconvolution approach is a widely used reconstruction algorithm in the field of radio synthesis imaging. However, parameter tuning for this algorithm has always been a difficult task. Here, its performance is improved by considering some internal characteristics of the data. From a mathematical point of view, a peak signal-to-noise-based(PSNRbased) method was introduced to optimize the step length of the steepest descent method in the recovery process. We also found that the loop gain curve in the new algorithm is a good indicator of parameter *** show that the new algorithm can effectively solve the problem of oscillation for a large fixed loop gain and provides a more robust recovery.

关键词： methods data analysis-techniques image processing-techniques interferometric

Charge resolution in the isochronous mass spectrometry and the mass of ^(51)Co

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Nuclear Science and Techniques 2021年第4期32卷 30-37页

作者： Xu Zhou Meng Wang Yu-Hu Zhang Hu-Shan Xu You-Jin Yuan Jian-Cheng Yang Yu.A.Litvinov S.A.Litvinov Bo Mei Xin-Liang Yan Xing Xu Peng Shuai Yuan-Ming Xing Rui-Jiu Chen Xiang-Cheng Chen Chao-Yi Fu Qi Zeng Ming-Ze Sun Hong-Fu Li Qian Wang Tong Bao Min Zhang Min Si Han-Yu Deng Ming-Zheng Liu Ting Liao Jin-Yang Shi Yu-Nan Song Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China GSI Helmholtzzentrum fu¨r Schwerionenforschung Planckstraße 164291 DarmstadtGermany Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of Science Xi’an Jiaotong UniversityXi’an 710049China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China CNRS/IN2P3 IJCLabUniversite´Paris-Saclay91405 OrsayFrance

Isochronous mass spectrometry(IMS)of heavyion storage rings is a powerful tool for the mass measurements of short-lived *** IMS experiments,masses are determined through precision measurements of the revolution times of the ions stored in the ***,the revolution times cannot be resolved for particles with nearly the same mass-to-charge(m/q)*** overcome this limitation and to extract the accurate revolution times for such pairs of ion species with very close m/q ratios,in our early work on particle identification,we analyzed the amplitudes of the timing signals from the detector based on the emission of secondary ***,the previous data analysis method is further improved by considering the signal amplitudes,detection efficiencies,and number of stored ions in the ring.A sensitive Z-dependent parameter is introduced in the data analysis,leading to a better resolution of ^(34)Ar^(18+) and ^(51)Co^(27+) with A/Z=17/*** mean revolution times of ^(34)Ar^(18+) and ^(51)Co^(27+) are deduced,although their time difference is merely 1.8 *** uncorrected,overlapped peak of these ions has a full width at half maximum of 7.7 *** mass excess of ^(51)Co was determined to be-27;332e41T keV,which is in agreement with the previous value of-27;342e48T keV.

关键词： Isochronous mass spectrometry Charge resolution Signal amplitude Micro-channel plate ^(51)Co

Taxonomic revision of Amolops chunganensis(Pope,1929)(Amphibia: Anura) and description of a new species from southwestern china, with discussion on Amolops monticola group and assignment of species groups of the genus Amolops

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Zoological Research 2021年第5期42卷 574-591页

作者： Ke Jiang Jin-Long Ren Zhi-Tong Lyu Dan Wang Zeng Wang Ke Lv Jia-Wei Wu Jia-Tang Li cas Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengduSichuan 610041China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Biocontrol/The Museum of Biology School of Life Sciences/School of EcologySun Yat-Sen UniversityGuangzhouGuangdong 510275China Swild Studio ChengduSichuan 610015China Chengdu Expert Advisory Committee for Wildlife Conservation and Epidemic Prevention ChengduSichuan 610000China

Amolops chunganensis is a species complex and reported widely from eastern,southern,and southwestern *** on molecular data of 19 populations of *** sensu lato from china,including the population from ***(type locality),we recognize *** sensu stricto and provide an expanded description based on the topotypic *** morphological and molecular data,we describe a new species,Amolops chaochin ***.,from southwestern china,which was previously identified as *** new species is distinguished from all other species in the *** group by:(1)moderate body size,SVL 35.3-39.2 mm in males(n=7),and 50.5-54.4 mm in females(n=7);(2)distinct tympanum,larger than half of eye diameter;(3)small tooth-like projection on anteromedial edge of mandible;(4)circummarginal groove on all fingers;(5)white tubercles on dorsal side of posterior body in both sexes;(6)distinct tubercles on dorsal thigh and white spinose tubercles on dorsal tibia in both sexes;(7)white tubercles on posterior region of tympanum in males;(8)toe webbing reaching disk by dermal fringe on inner side of toe II;(9)vomerine teeth present;(10)transverse bands on dorsal limbs;(11)external vocal sacs present in *** further reviewed the assignment of Amolops groups,with an overall revision of membership and diagnosis of all species groups.

关键词： Amolops chaochin sp.nov. Complex Distribution Amolops gerbillus Amolops chayuensis group Amolops spinapectoralis group

Geochronology, geochemistry, and Sr-Nd isotopes of Early Carboniferous magmatism in southern west Junggar, northwestern china: Implications for Junggar oceanic plate subduction

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Journal of Arid Land 2021年第11期13卷 1163-1182页

作者： LIU Pengde LIU Xijun XIAO Wenjiao ZHANG Zhiguo SONG Yujia XIAO Yao LIU Lei HU Rongguo WANG Baohua Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration College of Earth SciencesGuilin University of TechnologyGuilin 541004China Xinjiang Research Center for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resource Guilin University of TechnologyGuilin 541004China

west Junggar is a key area for understanding intra-oceanic plate subduction and the final closure of the Junggar *** of the Carboniferous tectonic evolution of the Junggar Ocean region is required for understanding the tectonic framework and accretionary processes in west Junggar,Central Asian Orogenic Belt.A series of Early Carboniferous volcanic and intrusive rocks,namely,basaltic andesite,andesite,dacite,and diorite,occur in the Mayile area of southern west Junggar,northwestern *** new LA-ICPMS zircon U-Pb geochronological data reveal that diorite intruded at 334(±1)Ma,and that basaltic andesite was erupted at 334(±4)*** intrusive and volcanic rocks are calc-alkaline,display moderate MgO(1.62%-4.18%)contents and Mg#values(40-59),and low Cr(14.5×10-6-47.2×10-6)and Ni(7.5×10-6-34.6×10-6)contents,and are characterized by enrichment in light rare-earth elements and large-ion lithophile elements and depletion in heavy rare-earth elements and high-field-strength elements,meaning that they belong to typical subduction-zone island-arc *** samples show low initial 87Sr/86Sr ratios(range of 0.703649-0.705008),positiveεNd(t)values(range of 4.8-6.2 and mean of 5.4),and young TDM Nd model ages ranging from 1016 to 616 Ma,indicating a magmatic origin from depleted mantle involving partial melting of 10%-25%garnet and spinel *** our results with those of previous studies,we suggest that these rocks were formed as a result of northwestward subduction of the Junggar oceanic plate,which caused partial melting of sub-arc *** conclude that intra-oceanic arc magmatism was extensive in west Junggar during the Early Carboniferous.

关键词： Early Carboniferous magmatism geochronology geochemistry Junggar Oceanic plate subdution west Junggar Central Asian Orogenic Belt