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The rate of deadwood decomposition processes in tree stand gaps resulting from bark beetle infestation spots in mountain forests

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Forest Ecosystems 2024年第3期11卷 339-346页

作者： Ewa Błonska Adam gorski Jarosław Lasota Department of Ecology and Silviculture Faculty of ForestryUniversity of Agriculture in Krakow29 Listopada 46 Str.31-425KrakowPoland

Decaying wood is an essential element of forest ecosystems and it affects its other *** aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest *** research was carried out in the Babiog orski National *** research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle *** plots were located in undisturbed *** research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 *** samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was *** characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture *** decomposition of wood in the gaps regardless of the species is related to lower *** wood species covered by the study differed in the decomposition *** wood samples were characterized by a significantly higher decomposition rate compared to beech wood *** research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood.

关键词： Bark beetle Beech Decomposition rate Forest ecosystem Mass decline Spruce Woody debris

Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region

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Journal of Forestry Research 2024年第1期35卷 213-228页

作者： Fatma Selcen Sakar gürcan güleryüz Department of Biology Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biology Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest *** the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(Fo),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 *** locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest *** had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),*** the lowest(30.5±4.2 kg ha^(-1) a^(-1)).our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N *** acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： oldest forest communities Nitrogen mineralization Nitrification Tannic acid Total phenolic Litter

Evaluation of formation susceptibility and sand production potential in an offshore field,Niger Delta Basin,Nigeria

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Energy geoscience 2024年第1期5卷 1-11页

作者： David o.Ubuara Yinka A.olayinka godwin o.Emujakporue geoffrey C.Soronnadi-ononiwu Department of geology University of Port HarcourtNigeria Mease Energy Nigeria Limited Port HarcourtNigeria Department of geology University of IbadanNigeria Department of Physics University of Port HarcourtNigeria

Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil *** vulnerability of lithologic formations to wellbore instability and resultant sand production is investigated in the four delineated reservoirs of the“Areo”field,western part of Niger Delta *** foundation for establishing the geomechanical properties in this study was a 1-dimensional mechanical earth model,using gamma ray(gR),density(RHoB),compressional slowness(DTC),and shear slowness(DTS)*** the Areo oil field,two wells(well 001 and well 002)were *** evaluated formations are still primarily composed of compacted shale and unconsolidated sandstone,with reservoir sand units exhibiting lower elastic and rock strength properties than shale *** compressibility and porosity make sand more brittle,while low compressibility and porosity make shale stiffer due to high *** maximum force that can be applied to a shale unit without causing it to fail is 17.23 MPa,which is the maximum average rock strength of the *** means that shale requires more vertical stress or pressure than sand does in order to deform it(15.06 MPa).The three sand prediction approaches used in the analysis of sand production predictions have cut-off values that are higher than the average values of the *** Schlumberger sand production index method(S/I)indicates that the reservoir has potential for sand influx in the two wells,with the average of the four reservoirs studied in wells 001 and 002 being 1.551012 psi and 1.141012 psi ***,when a formation's sand production index is less than 1.241012 psi,as it is in this study,the formation is likely to produce *** findings support the notion that the defined sandstone units are highly unconsolidated and have a high potential for producing sands;therefore,sand control techniques must be factored in

关键词： Wireline log Stress geo-mechanicanical characterization Sand prediction Niger delta

Collective coherent emission of electrons in strong laser fields and perspective for hard x-ray lasers

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Matter and Radiation at Extremes 2024年第2期9卷 1-3页

作者： E.g.gelfer A.M.Fedotov o.Klimo S.Weber Extreme Light Infrastructure ERIC ELI Beamlines Facility25241 Dolní BřežanyCzech Republic HiLASE Centre Institute of Physics of the Czech Academy of Sciences25241 Dolní BřežanyCzech Republic National Research Nuclear University MEPhI Moscow 115409Russia FNSPE Czech Technical University in Prague11519 PragueCzech Republic

Coherent motion of particles in a plasma can imprint itself on *** recent advent of high-power lasers—allowing the nonlinear inverse Compton-scattering regime to be reached—has opened the possibility of looking at collective effects in laser–plasma *** certain conditions,the collective interaction of many electrons with a laser pulse can generate coherent radiation in the hard x-ray *** perspective paper explains the limitations under which such a regime might be attained.

关键词： laser scattering coherent

Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： Dmitry o.Kudryavtsev Yulia V.Sotnikova Vladislav A.Stolyarov Timur V.Mufakharov Valery V.Vlasyuk Margarita L.Khabibullina Alexander g.Mikhailov Yulia V.Cherepkova Special Astrophysical observatory of the Russian Academy of Sciences Nizhny Arkhyz 369167Russia Astrophysics group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal University 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwavelength data, namely in the radio(NVSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), UV(gALEX), and X-ray(RoSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SoMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the TeVCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies active-(galaxies:)BL Lacertae objects general

Sustainable Biocomposites Materials for Automotive Brake Pad Application:An overview

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Journal of Renewable Materials 2024年第3期12卷 485-511页

作者： Joseph o.Dirisu Imhade P.okokpujie olufunmilayo o.Joseph Sunday o.oyedepo oluwasegun Falodun Lagouge K.Tartibu Firdaussi D.Shehu Department of Mechanical Engineering Covenant UniversityOtaOgunNigeria Department of Mechanical and Mechatronics Engineering AFE Babalola UniversityAdoEkitiNigeria Department of Mechanical and Industrial Engineering Technology University of JohannesburgJohannesburg2028South Africa School of Chemical and Metallurgical Engineering University of the WitwatersrandJohannesburgSouth Africa

Research into converting waste into viable eco-friendly products has gained global *** natural fibres and pulverized metallic waste becomes necessary to reduce noxious environmental emissions due to indiscriminately occupying the *** study reviews the literature in the broad area of green composites in search of materials that can be used in automotive brake *** made by biocomposite,rather than fossil fuels,will be favoured.A database containing the tribo-mechanical performance of numerous potential components for the future green composite was established using the technical details of bio-polymers and natural *** development of materials with diverse compositions and varying proportions is now conceivable,and these materials can be permanently connected in fully regulated *** explanation demonstrates that all of these variables affect friction coefficient,resistance to wear from friction and high temperatures,and the operating life of brake pads to varying *** this study,renewable materials for the matrix and reinforcement are screened to determine which have sufficient strength,coefficient of friction,wear resistance properties,and reasonable costs,making them a feasible option for a green *** most significant,intriguing,and unusual materials used in manufacturing brake pads are gathered in this review,which also analyzes how they affect the tribological characteristics of the pads.

关键词： Asbestos brake pad biocomposites green composite mechanical properties natural reinforcement waste

A native herbaceous community exerts a strong allelopathic effect on the woody range-expander Betula fruticosa

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Journal of Plant Ecology 2024年第4期17卷 131-140页

作者： Lichao Wang Ayub M.o.oduor Yanjie Liu State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Department of Applied Biology Technical University of KenyaNairobiKenya

Biological invasions by alien and range-expanding native plant species can suppress native plants through ***,the homeland security hypothesis suggests that some native plants can resist invasion by producing allelopathic compounds that inhibit the growth of invasive *** research has focused on allelopathic interactions between individual native and invasive plant species,with less emphasis on how allelopathy helps entire native communities resist ***,limited knowledge exists about allelopathic interactions between range-expanding native species and recipient native communities,and their influence on invasion *** bridge this knowledge gap,we conducted two greenhouse competition experiments to test reciprocal allelopathic effects between a native woody range-expanding species,Betula fruticosa,and a community of four native herbaceous species(Sanguisorba officinalis,gentiana manshurica,Sium suave and Deyeuxia angustifolia)in *** assessed whether *** and the native community differed in their competitive effects and responses,and whether these were influenced by activated carbon,which neutralizes allelochemicals in the *** carbon reduced the suppressive effects of the native community on the above-ground biomass of ***,which indicates that the native community exerted a strong allelopathic effect on *** contrast,activated carbon only marginally enhanced the suppressive effects of *** on the native community,which indicates that allelopathy is not the primary mechanism by which *** exerts its ***,these findings support the homeland security hypothesis and suggest that biotic resistance from the native herbaceous community may limit the invasion success of the woody range-expander ***.

关键词： allelochemicals competition encroachment global change non-native shrub

A theoretical framework for improved fire suppression by linking management models with smart early fire detection and suppression technologies

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Journal of Forestry Research 2024年第5期35卷 1-13页

作者： Li Meng Jim o’Hehir Jing gao Stefan Peters Anthony Hay University of South Australia AdelaideSAAustralia Esk Spatial InvermayTASAustralia

Bushfires are devastating to forest managers,owners,residents,and the natural *** tech-nological advances indicate a potential for faster response times in terms of detecting and suppressing ***,to date,all these technologies have been applied in *** paper introduces the latest fire detection and sup-pression technologies from ground to *** operations research method was used to assemble these technologies into a theoretical framework for fire detection and *** framework harnesses the advantages of satellite-based,drone,sensor,and human reporting technologies as well as image processing and artificial intelligence machine *** study concludes that,if a system is designed to maximise the use of available technologies and carefully adopts them through complementary arrangements,a fire detection and resource suppression system can achieve the ultimate aim:to reduce the risk of fire hazards and the dam-age they may cause.

关键词： Forest fire Resource suppression Smart fire detection and suppression system Forest fire management Holistic system

Unraveling the interaction between soil microbiomes and their potential for restoring polluted soils

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 149-151页

作者： Carlos o.Lomeli-ortega Mingming Sun Jose Luis Balcazar Catalan Institute for Water Research(ICRA-CERCA) Girona 17003Spain University of girona Girona 17004Spain Soil Ecology Laboratory College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China

Soils are not exempt from anthropogenic pollution,which can eventually cause disturbance of the microbial communities and areas without any kind of *** soil microbiota,bacteria play an important role in pollutant degradation,enabling them to thrive in contaminated *** this,several techniques have been used to increase the number of pollutantdegrading bacteria in situ or for subsequent ***,bacteriophages exhibit a high tolerance to pollutants and enhance bacterial metabolic activity through phage-encoded auxiliary metabolic genes(AMgs),thereby augmenting their skills for nutrient assimilation,resistance to phage infection,antibiotic resistance,heavy metal resistance,and degradation of pesticides and xenobiotics,among *** phage-encoded AMgs have been described during the last few years,but their diversity,distribution,and function have not been extensively explored,warranting further ***,we highlight soil microbiome interactions,especially bacterium and phage interactions to understand this unexplored world with a high potential for restoring polluted soils.

关键词： Auxiliary metabolic genes Microbiome Pollutants Soils Viruses