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Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David I.Forrester hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben hilmers Zuzana sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain swiss Federal Institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CsIRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain IuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian state Institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. however, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic ***: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to *** methods and information theory were used to select the best ***: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their ***: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of th

关键词： Competition coefficient Competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

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杉木苗期施氮对二年生生长的影响

福建林学院学报 1989年第3期9卷 303-309页

作者：范少辉俞新妥杉木研究所

为了研究杉木苗期施氮的后期效应,我们在盆栽条件下对一年生杉苗按0.0、0.4、0.8、1.2、1.6、2.0g氮/盆6个水平进行施肥,结果表明:苗期施用氮肥对二年生杉苗的生长仍有十分显著的影响,二年生杉苗的苗高、地径、生物量(干重)积累、分枝... 详细信息

为了研究杉木苗期施氮的后期效应,我们在盆栽条件下对一年生杉苗按0.0、0.4、0.8、1.2、1.6、2.0g氮/盆6个水平进行施肥,结果表明:苗期施用氮肥对二年生杉苗的生长仍有十分显著的影响,二年生杉苗的苗高、地径、生物量(干重)积累、分枝数、分枝总长等各项生长指算随施氮水平的变化趋势均与一年生时相似;h/D值、T/R值与根、茎、叶占全苗比重等各项比例在不同的施氮水平之间有著差异,但在一年生和二年生之间无显著差异;当仅以苗高、地径、根长来评价其二年生生长效应时,可以认为苗期施氮无效,但综合生物量枳累和分枝特性指算,施氮的效应显著。

关键词：杉木苗期施肥氮肥二年生生长后期后长肥效

spectroscopic analysis of trivalent Nd3+/Yb3+ions codoped in PZs host glasses as a new laser material at 1.06μm

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Journal of Rare Earths 2017年第4期35卷 361-367页

作者： B.Afef h.h.hegazy h.Algami Y.Yang K.Damak E.Yousef R.Maalej Georessoures Materials Enviroment and Global Changes Laboratory Faculty of SciencesUniversity of SfaxSfax 3018Tunisia Department of Physics Faculty of SciencesAI Azhar UniversityAssuit branchAssuit 11795Egypt Department of Physics Faculty of SciencesKing Kha[id UniversityP.O.Box 9004Abha 61466Saudi Arabia College of Physics science and Technology Hebei UniversityBaoding 071002China Department of Physics Pukyong National UniversityBusan 608-737Republic of Korea

This paper reports on the spectral results of Nd3＋/yb3＋ ions codoped 50P2Os-30ZnO-20srO （PZs, in mol.%） glasses which were prepared by a melting technique. The glass transition temperature and spectroscopic properties of these glasses were estimated. From the absorption spectra, Judd-Ofelt （J-O） intensity parameters （Ωk）, were calculated. Using J-O intensity parameters, several radiative properties such as spontaneous transition probabilities （AR）, radiative branching ratios （fir） and radiative lifetimes （rR） were determined for the exciting levels of the Nd3＋ ions. The large value of the stimulated integrated cross-section and the lifetimes of Nd3~ level revealed the potential of the present glasses as a candidate for generating laser emission at 1.06/am as continuous wave laser action and exploited for optical device fabrication. A broad emission band from 950 to 1100 nm was detected when the Nd3＋/yb3＋ was co-doped in PZs glasses excited by 805 nm lighting diode （LD）. The energy transfer process from Nd3＋--→Yb3＋ in co-doped phos- phate glasses was described in this paper.

关键词： phosphate glasses Nd3+,yb3+ ions optical spectroscopy Judd-Ofelt analysis luminescence rare earths

Numerical approach to the modelling of transient interaction of prospective combustor concepts and conventional high pressure turbines

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Propulsion and Power Research 2019年第1期8卷 1-12页

作者： F.Bakhtiari h.-P.schiffer Technische University Darmstadt Institute of Gas Turbines and Aerospace PropulsionDarmstadt 64287HessenGermany

The Institute of Gas Turbines and Aerospace Propulsion at Technische Universitait Damstaxlt conducts research projects in the field of“combustor turbine interaction”(CTI).This paper presents numerical studies on the interaction between novel combustion concepts and conventional“high pressure turbine”(hPT)*** order to obtain higher efficiency and reduce emissions of jet engines,it is necessary to apply innovative and revolutionary *** most promising technical solutions are based on the cycle processes,employing“pressure gain combustion”(PGC)methods PGC methods provide a significant thermal efficiency enhancement and low NO_(x)-emission rates at the same *** investigations presented in this paper give information on the integrability of revolutionary combustion concepts into conventional engine *** paper aims at providing insight into the numerical modelling of the transient behaviour of prospective combustion outflow and its influence on the operation of hPTs,especially on the first *** focus is on the aerodynamic effects and loss mechanisms within the blade *** interaction between the two components plays an important *** study the performance under new conditions,an engine-like hPT geometry is *** study reveals a decrease in turbine efficiency with transient inflow conditions compared to a steady-state inflow *** decrease is primarily due to the interation between transient inflow and the loss mechanisms in the *** presented research was done as part of the project“Technologien fir REVolutionire Arbeits Prozesse”(TREVAP)

关键词： Combustor turbine interaction(CTI) Prospective combustor concepts Pressure gaincombus-tion(PGC) high pressureturbine(hPT) Transient computa-tional fluid dynamics(CFD)

Assessment and Analysis of Rockfall-Caused Tree Injuries in a Turkish fir.stand:A Case study from Kastamonu-Turkey

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Journal of Mountain science 2012年第2期9卷 137-146页

作者： Abdurrahim AYDIN Nesibe KsE nal AKKEMK hüseyin YURTsEVEN Düzceüniversity Faculty of ForestryKonuralp Campus Faculty of Forestry Department of Forest BotanyIstanbul University Faculty of Forestry Department of Surveying and PhotogrammetryIstanbul University

Rockfalls can cause serious damage to people,property,facilities and transportation ***,rockfalls are major hazards in mountain areas with negative impacts on individual trees and forested *** conducted a study of rockfall events on 117 mapped(91% of total trees in the stand with>1.3 m in height and>5 cm diameter at breast height)Turkish fir trees(Abies bornmuelleriana Mattf.)in a stand within the Kayaarkasi-Topular Village,Inebolu district, Kastamonu province of *** study site of 0.35 ha is located on the transition zone of frequently passing rockfall fragments(～40 cm in diameter) generally causing healable *** of trees and injuries were recorded and analysed as to injury number,height and *** correlation analysis were used to investigate the relationships between:a)diameter at breast height and number of injuries per tree,b)diameter at breast height and total injury size,c)the number of injuries and total injury size and d)the number of injuries per tree and distance from the source of the rockfall *** indicate that the average height of injury,average number of injuries and average injury area to be 81.3 cm(sTDEV:49.8),7.46(sTDEV:4.4)and 628.6 cm2 (sTDEV:678.2),*** total 84% of all injuries were recorded within 160°sector at the upslope side of trees and callus tissue that had closed wounds was observed in 79.1% of all injuries. Furthermore 14.5% of injured trees had callus tissue in the process of closing wounds while 6.4% of injuries had not formed any callus *** most common injury types were bark and wood injuries. Bivariate correlation analysis indicated strong relationships between diameter at breast height and the number of injuries(rs=0.524),injury number and total injury area(rs=0.653)and distance from rockfall area and injury numbers relations(rs=-0.518).A weaker relationship was found between diameter at breast height and total injury area(rs=0.363).These results

关键词： Tree injuries Rockfall Past event assessment Turkish fir Turkey

Measurements of dihadron correlations relative to the event plane in Au+Au collisions at√^(s)NN=200 GeV

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Chinese Physics C 2021年第4期45卷 198-241页

作者： h.Agakishiev M.M.Aggarwal Z.Ahammed A.V.Alakhverdyants I.Alekseev J.Alford B.D.Anderson C.D.Anson D.Arkhipkin G.s.Averichev J.Balewski D.R.Beavis N.K.Behera R.Bellwied M.J.Betancourt R.R.Betts A.Bhasin A.K.Bhat h.Bichsel J.Bieleik J.Bielcikova B.Biritz L.C.Bland W.Borowski J.Bouchet E.Braidot A.V.Brandin A.Bridgeman s.G.Brovko E.Bruna s.Bueltmann I.Bunzarov T.P.Burton X.Z.Cai h.Caines M.Calderon de la Barca sanchez D.Cebra R.Cendejas M.C.Cervantes Z.Chajecki P.Chaloupka s.Chattopadhyay h.F.Chen J.h.Chen J.Y.Chen L.Chen J.Cheng M.Cherney A.Chikanian K.E.Choi W.Christie P.Chung M.J.M.Codrington R.Corliss J.G.Cramer h.J.Crawford s.Dash A.Davila Leyva L.C.De silvat R.R.Debbe T.G.Dedovich A.A.Derevschikov R.Derradi de souza L.Didenko P.Djawotho s.M.Dogra X.Dong J.L.Drachenberg J.E.Draper J.C.Dunlop L.G Efimov M.Elnim J.Engelage G Eppley M.Estienne L.Eun O.Evdokimov R.Fatemi J.Fedorisin A.Feng R.G.Fersch P.Filip E.Finch V.Fine Y.Fisyak C.A.Gagliardi D.R.Gangadharan A.Geromitsos F.Geurts P.Ghosh Y.N.Gorbunov A.Gordon O.Grebenyuk D.Grosnick s.M.Guertin A.Gupta W.Guryn B.haag O.hajkova A.hamed L-X.han J.W.harris J.P.hays-Wehle M.heinz s.heppelmann A.hirsch E.hjort G.W.hoffmann D.J.hofiman B.huang h.Z.huang T.J.humanic L.huo G.Igo P.Jacobs W.W.Jacobs C.Jena F.Jin J.Joseph E.G.Judd s.Kabana K.Kang J.Kapitan K.Kauder h.Ke D.Keane A.Kechechyan D.Kettler D.P.Kikola J.Kiryluk A.Kisiel V.Kizka A.G.Knospe D.D.Koetke T.Kollegger J.Konzer I.Koralt L.Koroleva W.Korsch L.Kotchenda V.Kouchpil P.Kravtsov K.Krueger M.Krus L.Kumar P.Kurnadi M.A.C.Lamont J.M.Landgraf s.LaPointe J.Lauret A.Lebedev R.Lednicky J.h.Lee W.Leight M.J.LeVine C.Lil L.Li N.Li W.Li X.Li X.Li Y.Li Z.M.Li M.A.Lisa F.Liu h.Liu J.Liu T.Ljubicic W.J.Llope R.s.Longacre W.A.Love Y.Lu E.V.Lukashov X.Luo G.L.Ma Y.G.Mai D.P.Mahapatra R.Majka O.I.Mall L.K.Mangotra R.Manweiler s.Margetis C.Markert h.Masui h.s.Matis Yu.A.Matulenko D.MeDonald T.s.Mcshane A.Meschanin R.Milner N.G.Minaev s.Mioduszewski A.Mischke M.K.Mitrovski B.Mohanty M.M.Mondal B.Morozov D.A.Morozov M.G.Munhoz M Argonne National Laboratory Argonnellinois 60439USA Brookhaven National Laboratory UptonNew York 11973USA University of Califomia BerkeleyCaliformnia 94720USA University of California DavisCalifornia 95616USA University of Califormnia Los AngelesCalifomia 90095USA Universidade Estadual de Campinas Sao PauloBrazil University of Illinois at Chicago ChicagoIlinois 60607USA Creighton University OmahaNebraska 68178USA Czech Technical University in Prague FNSPEPrague11519Czech Republic Nuclear Physics Institute As CR 25068 Rez/PragueCzech Republic University of Frankfurt FrankfurtGermany Institute of Physics Bhubaneswar 751005India Indian Institute of Technology MumbaiIndia Indiana University BloomingtonIndiana 47408USA Alikhanov Instiute for Theoretical and Experimental Physics MoscowRussia University of Jammu Jammu 180001India Joint Institute for Nuclear Research Dubna141980Russia Kent state University KentOhio 44242USA University of Kentucky LexingtonKentucky40506-0055USA Institute of Modern Physics LanzhouChina Lawrence Berkeley National Laboratory BerkeleyCalifornia 94720USA Massachusetts Institute of Technology CambridgeMA 02139-4307USA Mx-Planck-Institut fir Physik MunichGermany Michigan state University East LansingMichigan 48824USA Moscow Engineering Physics Institute Moscow Russia NIKhEF and Utrecht University AmsterdamThe Netherlands Ohio state University ColumbusOhio 43210USA Old Dominion University NorfolkVA23529USA Panjab University Chandigarh 160014India PennsyIvania state University University ParkPennsylvania 16802USA Institute of high Energy Physics ProtvinoRussia Purdue University West LafayetteIndiana 47907USA Pusan National University PusanRepublic of Korea University of Rajasthan Jaipur 302004India Rice University HoustonTexas 77251USA Universidade de sao Paulo Sao PauloBrazil University of science&Technology of China Hefei 230026.China shandong University JinanShandong 250100China shanghai Institute of Applied Physics Shanghai 201800Chi

Dihadron azimuthal correlations containing a high transverse momentum(pr)trigger particle are sensit-ive to the properties of the nuclear medium created at RhIC through the strong interactions occurring between the traversing parton and the medium,*** measurements revealed a strong modification to di-hadron azimuthal correlations in Au+Au collisions with respect to ptp and d+Au *** modification in-creases with the collision centrality,suggesting a path-length or energy density dependence to the je-quenching *** paper reports sTAR measurements of dihadron azimuthal correlations in mid-central(20%-60%)Au+Au collisions at√^(s)NN=200 GeV as a function of the trigger particle's azimuthal angle relative to the event plane,Ф_(s)=|Ф_(t)-ψ_(Ep)|.The azimuthal correlation is studied as a function of both the trigger and associated particle *** subtractions of the combinatorial background and anisotropic flow,assuming Zero Yield At Minimum(ZYAM),are *** correlation results are first discussed with subtraction of the even harmonic(elliptic and quadrangu-lar)flow *** away-side correlation is strongly modifed,and the modification varies withФ_(s),with a double-peak structure for out-of-plane trigger *** near-side ridge(long range pseudo-rapidity△_(η)correla-tion)appears to drop with increasingФ_(s)while the jet-like component remains approximately *** correla-tion functions are further studied with the subtraction of odd harmonic triangular flow background arising from *** is found that the triangular flow,while responsible for the majority of the amplitudes,is not sufficient to explain theφs-dependence of the ridge or the away-side double-peak *** dropping ridge withФ_(s)could be attributed to aФ_(s)-dependent lliptie anisotropy;however,the physics mechanism of the ridge remains an open *** with aФ_(s)-dependent elliptic flow,the away-side correlation structure

关键词： relativistic heavy ion collisions dihadron correlations jet-medium interactions anisotropic flow background event plane

Design and Implementation of Low-Pass, high-Pass and Band-Pass Finite Impulse Response (fir) Filters Using FPGA

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Circuits and systems 2015年第2期6卷 30-48页

作者： Emmanuel s. Kolawole Warsame h. Ali Penrose Cofie John Fuller C. Tolliver Pamela Obiomon Department of Electrical and Computer Engineering Prairie View A&M University Prairie View USA

This paper presents the design and implementation of a low-pass, high-pass and a hand-pass Finite Impulse Response (fir) Filter using sPARTAN-6 Field Programmable Gate Array (FPGA) device. The filter performance is tested using Filter Design and Analysis (FDA) and fir tools from Mathworks. The FDA Tool is used to define the filter order and coefficients, and the fir tool is used for simulink simulation. The FPGA implementation is carried out using spartan-6 LX75T-3FGG676C for different filter specifications and simulated with the help of Xilinx IsE (Integrated software Environment). system Generator IsE design suit 14.6i is used in synthesizing and co-simulation for FPGA filter output verification. Finally, comparison is done between the results obtained from the software simulations and those from FPGA using hardware co-simulation. The simulation waveforms and synthesis reports verify the parallel implementation of FPGA which proves its effectiveness in terms of speed, resource usage and power consumption.

关键词： Digital Filters fir Filter Matlab simulink FDA Tool fir Tool Distributed Arithmetic FPGA Xilinx system Generator

Thinning and in-stream wood recruitment in riparian second growth forests in coastal Oregon and the use of buffers and tree tipping as mitigation

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Journal of Forestry Research 2016年第4期27卷 821-836页

作者： Lee E.Benda s.E.Litschert Gordon Reeves Robert Pabst TerrainWorks Mt. Shasta CA 96067 USA BLM National Operations Center Denver CO 80225-0047USA Pacific Northwest Research station U.S. Forest ServiceCorvallis OR 97331 USA Oregon state University Corvallis OR 97331 USA

Many aquatic habitats in coastal Oregon have been impacted by historic land use practices that led to losses of in-stream wood and associated degraded fish habitats. Many of these streams are now bordered by stands of dense second growth forests（30–80 years） that are incorporated into riparian buffer zones with low wood recruitment and storage. Thinning in riparian zones is one management option to increase the rate of large tree growth and eventually larger in-stream wood, however, it raises concern about impacts on current wood recruitment, among other issues. Using a forest growth simulation model coupled to a model of in-stream wood recruitment, we explore riparian management alternatives in a Douglas-fir plantation in coastal Oregon. Alternatives included：（1） no treatment,（2） single and double entry thinning, without and with a 10-m buffer, and（3） thinning combined with mechanical introduction of some portion of the thinned trees into the stream（tree tipping）. Compared to no treatment, single and double entry thinning on one side of a channel, without a 10-m buffer, reduce cumulative instream wood volume by 33 and 42 %, respectively, after100 years（includes decay）. Maintaining a 10-m buffer reduces the in-stream wood loss to 7 %（single entry thin）and 11 %（double entry）. To completely offset the losses of in-stream wood in a single entry thin（on one or both sides of the stream）, in the absence or presence of a 10-m buffer,requires a 12–14 % rate of tree tipping. Relative to the notreatment alternative, cumulative in-stream wood storage can be increased up to 24 % in a double-entry thin with no buffer by tipping 15–20 % of the thinned trees（increased to 48 % if thinning and tipping simultaneously on both sides of the stream）. The predicted increases in in-stream wood that can occur during a thin with tree tipping may be effective for restoring fish habitat, particularly in aquatic systems that have poor habitat conditions and low levels of in-stream wood due to h

关键词： thinning mitigation coastal Oregon forests habitat piece plantation stands cumulative

Genomic prediction of fruit texture and training population optimization towards the application of genomic selection in apple

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horticulture Research 2020年第1期7卷 889-902页

作者： Morgane Roth hélène Muranty Mario Di Guardo Walter Guerra Andrea Patocchi Fabrizio Costa Plant Breeding Research Division AgroscopeWädenswilZurichSwitzerland IRhs INRAEAgrocampus-OuestUniversitéd’AngersSFR 4207 QuaSaVBeaucouzéFrance Department of Genomics and Biology of Fruit Crops Research and Innovation CentreFondazione Edmund Mach(FEM)Via E.Mach 138010 San Michele all’AdigeItaly Department of Agriculture Food and Environment(Di3A)University of CataniaCataniaItaly Research Centre Laimburg Laimburg 639040 AuerItaly Center Agriculture Food Environment University of TrentoVia Mach 138010 San Michele all’AdigeItaly Present address:GAFL INRAE84140 MontfavetFrance

Texture is a complex trait and a major component of fruit quality in *** the major effect of MdPG1,a gene controlling firmness,has already been exploited in elite cultivars,the genetic basis of crispness remains poorly *** further improve fruit texture,harnessing loci with minor effects via genomic selection is therefore *** this study,we measured acoustic and mechanical features in 537 genotypes to dissect the firmness and crispness components of fruit *** of across-year phenotypic values for these components were calculated using a model calibrated with 8,294 sNP *** best prediction accuracies following cross-validations within the training set of 259 genotypes were obtained for the acoustic linear distance(0.64).Predictions for biparental families using the entire training set varied from low to high accuracy,depending on the family *** adding siblings or half-siblings into the training set did not clearly improve predictions,we performed an optimization of the training set size and composition for each validation *** allowed us to increase prediction accuracies by 0.17 on average,with a maximal accuracy of 0.81 when predicting firmness in the‘Gala’×‘Pink Lady’*** results therefore identified key genetic parameters to consider when deploying genomic selection for texture in *** particular,we advise to rely on a large training population,with high phenotypic variability from which a‘tailored training population’can be extracted using a priori information on genetic relatedness,in order to predict a specific target population.

关键词： prediction optimization fir