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Romanian legal management rules limit wood production in Norway spruce and beech forests

Forest Ecosystems 2017年第1期4卷 1-11页

作者： Olivier Bouriaud Gheorghe Marin Laura Bouriaud Dominik Hessenmoller ernst-detlef schulze National Forest Inventory National Research and Development Institute for Forestry INCDS Eroilor Bd. 128 Voluntari Romania University Stefan cel Mare Suceava RomaniaUniversitatii str.13Suceava 720229Romania. Department of Biogeochemical Processes Max Planck Institute for BiogeochemistryHans-Knoell-Str.10Jena 07745Germany

Background： The quantitative impact of forest management on forests＇ wood resource was evaluated for Picea and Fagus mixed forests. The effects on the productivity of tendering operations, thinnings and rotation length have seldom been directly quantified on landscape scale. Methods： Two sites of similar fertility but subject to contrasted forest management were studied with detailed inventories： one in Germany, the other in Romania, and compared with the respective national forest inventories. In Romania, regulations impose very long rotations, low thinnings and a period of no-cut before harvest. In contrast, tending and thinnings are frequent and intense in Germany. Harvests start much earlier and must avoid clear cutting but maintain a permanent forest cover with natural regeneration. While Germany has an average annual wood increment representative for Central Europe, Romania represents the average for Eastern Europe. Results： The lack of tending and thinning in the Romanian site resulted in twice as many trees per hectare as in the German site for the same age. The productivity in Romanian production forests was 20 % lower than in Germany despite a similar fertility. The results were supported by the data from the national forest inventory of each country, which confirmed that the same differential exists at country scale. Furthermore, provided the difference in rotation length, two crops are harvested in Germany when only one is harvested in Romania. The losses of production due to a lower level of management in Romania where estimated to reach 12.8 million m3.y-1 in regular mountain production forests, and to 15 million m3.y-1 if managed protection forest is included. Conclusions： The productivity of Picea and Fagus mountain forests in Romania is severely depressed by the lack of tending and thinning, by overly long rotations and the existence of a 25-years no-cut period prior to harvest. The average standing volume in Germany was 50 % lower than in Romania,

关键词： Forest management Forest productivity Legal rules Sylviculture Forest Operations Wood resource

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Plant diversity and community history shift colonization success from early- to mid-successional species

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Journal of Plant Ecology 2015年第3期8卷 231-241页

作者： Christiane Roscher Uta Gerighausen Bernhard Schmid ernst-detlef schulze UFZ Helmholtz Centre for Environmental ResearchDepartment of Community EcologyTheodor-Lieser-Strasse 4D-06120 HalleGermany Max Planck Institute for Biogeochemistry PO Box 100164D-07701 JenaGermany Institute of Evolutionary Biology and Environmental Studies and Zurich-Basel Plant Science Center University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland

Aims Functional traits are supposed to play an important role in deter-mining the colonization success of new species into established ***-term experimental studies have documented higher resistance of more diverse grasslands against coloni-zation by new ***,little is known about which traits colonizers should have to successfully invade diverse plant communities in the longer term and how community his-tory may modify the resistance of diverse communities against *** In a grassland biodiversity experiment(Jena Experiment)established with different species richness(s;1,2,4,8 and 16)and functional group(Fg)number and composition(1 to 4;legumes,grasses,small herbs,tall herbs),we studied colonization of naturally dispersed species in split-plots(i)with different duration of weeding(never weeded,weeded for 3 or 6 years and then un-weeded for 1 year)and(ii)with different duration of colonization(7 years,4 years and 1 year after cessation of weeding).Important Findingsresistance against colonization by new species declined with increased duration of weeding(on average 13,17 and 22 col-onizer species in 1-,4-and 7-year-old communities,respec-tively).Communities established at low diversity accumulated more colonizer species with a longer duration of weeding than more diverse *** of colonization had only small effects on the number of colonizer *** with early successional traits,*** life cycle,reproduction by seeds,small seeds,long-lived seeds and an earlier start of a longer flowering period,were favoured in species-poor newly established experimental plant communities(short duration of weeding)and early after cessation of weeding(short duration of colonization).a change from early-to mid-successional traits,*** growth,perennial life cycle,vegetative reproduction,characterized colonization at increased plant diversity and in communities with legumes or without *** absence/gr

关键词： abundance-weighted community mean traits biodiversity colonization simple community mean traits species richness

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Positive association between forest management, environmental change, and forest bird abundance

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Forest Ecosystems 2019年第1期6卷 26-37页

作者： ernst detlef schulze Dylan Craven Andrew M.Durso Jiri Reif Marcus Guderle Franz Kroiher Petra Hennig Anne Weiserbs Peter Schall Christian Ammer Nico Eisenhauer Max Planck Institute for Biogeochemistry Biodiversity Macroecology and Biogeography Faculty of forest Science and Forest Ecology University G?ttingen Institute of Environmental Studies Faculty of ScienceCharles University Thünen-Institute for Forest Ecosystems Aves-Natagora Départment Etudes Silviculture and Forest Ecology of the temperate Zones University of G?ttingen German Centre for Integrative Biodiversity Research (iDiv) and Leipzig University Institute of Biology

Background: The global decrease in wildlife populations, especially birds, is mainly due to land use change and increasing intensity of land use(Parmesan and Yohe 2003). However, impacts of management tools to mitigate biodiversity loss at regional and global scales are less apparent in forest regions that have a constant forest area,and which did not suffer from habitat degradation, and where forests are sustainably managed, such as in Central Europe or the northeastern USA. A biodiversity assessment for Germany suggested, for example, that bird populations were constant(Bundesamt für Naturschutz 2015).Results: This study shows that changes in the environment and in forest management over the past 45 years have had a significant, positive effect on the abundance of non-migratory forest bird species in Central Europe. Economy(timber prices and GDP), forest management(timber harvest and mixed forest area), and environmental factors(atmospheric CO_2 concentration and nitrogen deposition) were investigated together with changes in abundances of migratory and non-migratory forest birds using partial least squares path modeling. Climate change, resulting in longer seasons and milder winters, and forest management, promoting tree diversity, were significantly positively related to the abundance of non-migratory forest birds and explained 92% of the variation in their abundance in Europe. Regionally-migrating forest birds had stable populations with large variation, while birds migrating across continents declined in recent decades, suggesting significant, contrasting changes in bird populations in Europe. In northeastern North America we also found evidence that non-migratory forests have experienced long-term increases in abundance, and this increase was related to management. The increase of populations of nonmigratory forest birds in Europe and North America is associated with an increase in structural diversity and disturbances at the landscape ***: Our

关键词： Climate change Birds Biodiversity Timber harvest Econo my Forest management

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Biodiversity and belowground interactions mediate community invasion resistance against a tall herb invader

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Journal of Plant Ecology 2010年第2期3卷 99-108页

作者： Christoph Scherber Peter NMwangi Martin Schmitz Michael Scherer-Lorenzen Holger Beßler Christof Engels Nico Eisenhauer Varvara DMigunova Stefan Scheu Wolfgang WWeisser ernst-detlef schulze Bernhard Schmid Agroecology Department of Crop ScienceUniversity of GottingenWaldweg 26D-37073 GottingenGermany Institute of Evolutionary Biology and Environmental Studies University of ZurichWinterthurerstraße 92CH-8057 ZurichSwitzerland Max Planck Institute for Biogeochemistry Hans-Knoll Straße 10D-07745 JenaGermany Institute of Ecology Jena UniversityDornburger Straße 159D-07743 JenaGermany Institut fur Biologie II/Geobotanik Schanzlestr.1D-79104 FreiburgGermany Humboldt Universitat zu Berlin Fachgebiet PflanzenernahrungAlbrecht-Thaer-Weg 4D-14195 BerlinGermany J.F.Blumenbach Institute of Zoology and Anthropology University of GottingenBerliner Str.28D-37073 GottingenGermany K.I.Skryabin All-Russian Institute of Helminthology Bolschaya Tcheryomuschkinskaya str.28117218 MoscowRussia

Aims Species-rich plant communities are hypothesized to be more resistant against plant invasions because they use resources in a more efficient ***,the relative contributions of aboveground competition and belowground interactions for invasion resistance are still poorly *** We compared the performance of Knautia arvensis transplants growing in plots differing in plant diversity both under full competition and with shoots of neighbors tied back to determine the relative strength of aboveground competition in suppressing this test invader without the confounding effect of *** addition,we assessed the effects of belowground competition and soil-borne pathogens on transplant *** Findings Both aboveground competition and plant species richness strongly and independently affected invader *** biomass,height,leaf mass per area and flowering of transplanted individuals of *** decreased with increasing species richness of the host ***-rich and species-poor communities both imposed equally strong aboveground competition on ***,belowground interactions(especially belowground root competition)had strong negative effects on transplant *** addition,the presence of grasses in a plant community further reduced the performance of *** results suggest that belowground competition can render species-rich host communities more suppressive to newly arriving species,thus enhancing community invasion resistance.

关键词： aboveground competition competitive suppression belowground interactions root competition shoot exclusion species richness

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National Forest Inventories capture the multifunctionality of managed forests in Germany

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Forest Ecosystems 2021年第1期8卷 50-68页

作者： Nadja K.Simons María R.Felipe-Lucia Peter Schall Christian Ammer Jürgen Bauhus Nico Blüthgen Steffen Boch François Buscot Markus Fischer Kezia Goldmann Martin M.Gossner Falk Hänsel Kirsten Jung Peter Manning Thomas Nauss Yvonne Oelmann Rodica Pena Andrea Polle Swen C.Renner Michael Schloter Ingo Schöning ernst-detlef schulze Emily F.Solly Elisabeth Sorkau Barbara Stempfhuber Tesfaye Wubet Jörg Müller Sebastian Seibold Wolfgang W.Weisser Terrestrial Ecology Research Group Technische Universität MünchenHans-Carl-von-Carlowitz-Platz 285354 FreisingGermany Present address:Ecological Networks Technische Universität DarmstadtSchnittspahnstraße 364287 DarmstadtGermany Helmholtz Centre for Environmental Research-UFZ Department of Ecosystem ServicesDeutscher Platz 5e04103 LeipzigGermany Present address:German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Silviculture and Forest Ecology of the Temperate Zones University of GöttingenBüsgenweg 137077 GöttingenGermany Centre for Biodiversity and Sustainable Land-use University of GöttingenBüsgenweg 137073 GöttingenGermany Chair of Silviculture Faculty of Environment and Natural ResourcesUniversity of FreiburgTennenbacherstr.479106 FreiburgGermany Ecological Networks Technische Universität DarmstadtSchnittspahnstraße 364287 DarmstadtGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland Biodiversity and Conservation Biology WSL Swiss Federal Research InstituteZürcherstrasse 1118903 BirmensdorfSwitzerland Helmholtz Centre for Environmental Research-UFZ Department of Soil EcologyTheodor-Lieser-Straße 406120 Halle(Saale)Germany German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Forest Entomology WSL Swiss Federal Research InstituteZürcherstrasse 1118903 BirmensdorfSwitzerland Department of Environmental Systems Science Institute of Terrestrial EcosystemsETH ZürichUniversitätstr 168092 ZürichSwitzerland Environmental Informatics University of MarburgDeutschhausstraße 1235032 MarburgGermany Evolutionary Ecology and Conservation Genomics Ulm UniversityAlbert-Einstein-Allee 1189069 UlmGermany Senckenberg Biodiversity and Climate Research Centre Senckenberganlage 2560325 Frankfurt am MainGermany Geoecology University of TübingenRümelinstraße 19-2372070 TübingenGermany Present address:Department of Sustaina

Background:Forests perform various important ecosystem functions that contribute to ecosystem *** many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem ***,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem *** on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem *** use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory ***:Looking at the potential supply of ecosystem services,we found trade-offs(*** both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(*** temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in *** single forest type provided all ecosystem services *** ecosystem services showed comparable levels across forest types(*** or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(*** availability or cover of edible plants)or tree species composition(*** nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental ***,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree ***:Our results show that forest multifunctionality is limited to subsets of ecosystem *** importance of tree species composition highlights that a lack of multifunctionality at the stand lev

关键词： Ecosystem processes and services Forest management Structural diversity Tree species composition Trade-offs and synergies Forest productivity

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CONJUGATE-SYMPLECTICITY OF LINEAR MULTISTEP METHODS

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Journal of Computational Mathematics 2008年第5期26卷 657-659页

作者： ernst Hairer Section de Mathématiques Univ.de Genève

For the numerical treatment of Hamiltonian differential equations, symplectic integrators are the most suitable choice, and methods that are conjugate to a symplectic integrator share the same good long-time behavior. This note characterizes linear multistep methods whose underlying one-step method is conjugate to a symplectic integrator. The bounded- hess of parasitic solution components is not addressed.

关键词： Linear multistep method Underlying one-step method Conjugate-symplecticity,Symmetry.

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Special materials in pyrotechnics Ⅶ: Pyrotechnics used in thermal batteries

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Defence Technology（防务技术） 2019年第3期15卷 254-263页

作者： ernst-Christian Koch Lutradyn Energetic Materials Science & Technology

Thermal batteries are unique direct current(DC) electrical power sources with long shelf live, high reliability and higher power density than classical alkaline batteries. This paper gives a brief overview into the working principle of thermal batteries and reviews the properties of zirconium/barium chromate(Zr/BaCrO4) pyrolant previously used as first fire and iron/potassium perchlorate(Fe/KClO4) pyrolant(Heat), commonly applied as heating pellet in thermal batteries and its hazard properties. The review gives 64 references to the public domain. CAS-Nos. Zr: [7440-67-7], BaCrO4: [10294-40-3], Fe: [7439-89-6], KClO4: [7778-74-7], Viton: [9011-17-0].CAS-Nos. Zr: [7440-67-7], BaCrO4: [10294-40-3], Fe: [7439-89-6], KClO4: [7778-74-7], Viton: [9011-17-0].

关键词： Barium chromate Heat-powder Iron Lithium Molten salt Potassium perchlorate Pyrotechnics Thermal battery Zirconium

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Insensitive high explosives:Ⅳ. Nitroguanidine-Initiation & detonation

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Defence Technology（防务技术） 2019年第4期15卷 467-487页

作者： ernst-Christian Koch Lutradyn-Energetic Materials

This paper reviews the detonative properties of low bulk density(LBD),high bulk density(HBD)Nitroguanidine(NGu)(1),CAS-No:[556-88-7]and 82 explosive formulations based on NGu reported in the public *** rank the performance of those formulations they are compared with 15 reference compositions containing both standard high explosives such as octogen(HMX)(2),hexogen(RDX)(3),pentaerythritol tetranitrate(PETN)(4),2,4,6-trinitrotoluene(TNT)(5)as well as insensitive high explosives such as 3-nitro-1,2,4-triazolone(NTO)(6),1,3,5-triamino-2,4,6-trinitrobenzene(TATB)(7),1,1-diamino-2,2-dinitroethylene(FOX-7)(8)and N-Guanylurea dinitramide(FOX 12)(9).NGu based formulations are superior to those based on FOX-12 or TATB and are a close match with FOX-7 based explosives,the latter just having higher Gurney Energies(-10%)and slightly higher detonation pressure(+2%).NGu based explosives even reach up to 78% of the detonation pressure,82% Gurney energy and up to 95% of detonation velocity of ***-NGu dissolves in many melt cast eutectics forming dense charges thereby eliminating the need for costly High Bulk Density *** based formulations are at the rock bottom of sensitiveness among all the above-mentioned explosives which contributes to the safety of these *** review gives 132 references to the public *** a review on the synthesis spectroscopy and sensitiveness of Nitroguanidine see Ref.[1].

关键词： Cook-off Detonation Insensitive munitions Nitroguanidine Shock sensitvity

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Using coalgebras and the Giry monad for interpreting game logics a tutorial

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Frontiers of Computer Science 2017年第6期11卷 948-970页

作者： ernst-Erich DOBERKAT Math++ Software Bochum 44879 Germany

The stochastic interpretation of Parikh＇s game logic should not follow the usual pattern of Kripke models, which in turn are based on the Kleisli morphisms for the Giry monad, rather, a specific and more general approach to proba- bilistic nondeterminism is required. We outline this approach together with its probabilistic and measure theoretic basis, in- troducing in a leisurely pace the Giry monad and its Kleisli morphisms together with important techniques for manipu- lating them. Proof establishing specific techniques are given, and pointers to the extant literature are provided. After working through this tutorial, the reader should find it easier to follow the original literature in this and related areas, and it should be possible for her or him to appreciate measure theoretic arguments for original work in the areas of Markov transition systems, and stochastic effectivity func- tions.

关键词： coalgebras modal logics monads Giry monad,upper closed monad composition of monads game logics

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Superlubricity on the nanometer scale

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Friction 2014年第2期2卷 106-113页

作者： ernst MEYER Enrico GNECCO Department of Physics University of BaselKlingelbergstr.824056 BaselSwitzerland IMDEA Nanociencia Campus Universitario de CantoblancoCalle Faraday 928049 MadridSpain

The transition from atomic stick-slip to continuous sliding has been observed in a number of *** extended contacts are moved in different directions,so-called structural lubricity is observed when the two surface lattices are ***,a“superlubric”state of motion can be achieved if the normal force is reduced below a certain threshold,the temperature is increased,or the contact is actuated *** processes have been partially demonstrated using atomic force microscopy,and they can be theoretically understood by proper modifications of the Prandtl−Tomlinson model.

关键词： structural lubricity dynamic superlubricity atomic force microscopy friction force microscopy themolubricity Prandtl−Tomlinson model

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