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41.
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Zusammenfassung:   Die Nachhaltigkeit richtete sich in der Gründerzeit der planmäßigen Forstwirtschaft auf die Holzproduktion (v. Carlowitz 1713, Cotta 1828, Hartig 1804, Hundeshagen 1826). In der Folgezeit wurde ein zunehmend breiteres Spektrum von Leistungen des Waldes in die Planung mit einbezogen (v. Hagen, 1867; Dieterich, 1957). Das heutige Verständnis von multifunktionaler Forstwirtschaft spiegelt sich in den sechs gesamteuropäischen Kriterien und Indikatoren für nachhaltige Forstwirtschaft wider (McPfe, 2000). Vorliegender Aufsatz umreißt, wie diese gesamteuropäischen Kriterien und Indikatoren für den Nachweis und die strategische Planung von Nachhaltigkeit auf Forstbetriebsebene eingesetzt werden können und was die Waldwachstumsforschung dazu beitragen kann. An einer Reihe von Beispielen wird ausgeführt, dass die Forstwirtschaft über eine solide Datenbasis für die Ableitung von Nachhaltigkeitskriterien und Indikatoren verfügt. Diese kann für das Monitoring der Waldentwicklung genutzt werden. Gestalterische Kraft entwickeln die Kriterien und Indikatoren aber erst, wenn sie auch in die strategische Planung einfließen. Für die strategische Planung stehen der Forstwirtschaft Wuchsmodelle, Betriebssimulatoren und Entscheidungsstützungssysteme zur Verfügung. Sofern diese die genannten Kriterien und Indikatoren berücksichtigen, ermöglichen sie Szenariorechungen auf Betriebsebene und eine umfassende Bewertung von Handlungsalternativen. Konzepte und Werkzeuge für den Übergang zu einer multifunktionalen strategischen Nachhaltsplanung sind weit entwickelt (v. Gadow 2003, Hanewinkel 2001, Pretzsch et al. 1998, Spellmann et al. 2001); ihre Einführung in die Forstplanung könnte einen beträchtlichen Innovationsstau beseitigen.  相似文献   
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Individuals were selected for resistance against the imperfect fungus Seiridium cardinale Wag in six common cypress populations (Cupressus sempervirens L.) in Greece. A total of 109 resistant clones and 140 trees from their base populations were surveyed at several allozyme loci. The comparison yielded information on changes in genetic variation due to artificial selection. The genetic structure of the breeding populations was similar to their base populations. Nevertheless, the number of rare alleles among the resistant clones had decreased, showing a similar trend at most loci and for most comparisons. Possible implications for breeding strategies are discussed.  相似文献   
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Ohne ZusammenfassungHerrn Professor Dr. Max Wolff (Naumburg/Saale), emeritierten Ordinarius für Forstzoologie und Forstparasitologie der damaligen Forsthochschule Eberswalde, in Verehrung nachträglich zum 80. Geburtstag (6. IX. 1959) gewidmet.  相似文献   
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In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis (crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative, as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
Sabine AugustinEmail:
  相似文献   
47.
On the basis of nine Norway spruce (Picea abies (L.) Karst.) and ten European beech (Fagus sylvatica L.) thinning experiments in Germany, for which both residual and removed stock had been registered first during 1870, I scrutinize how moderate and heavy thinning from below (B-, C-grade) affects the production of merchantable volume compared with light thinning (A-grade). In relation to A-grade, cumulative merchantable volume (CV) of B- and C-grade amounts in average to 103–107% in juvenile and to 97–102% in mature Norway spruce stands. The corresponding findings for European beech are 101–106% and 94–102%. CV of individual stands varies between 89% and 130% for Norway spruce and 73% and 155% for European beech (CV of A-grade = 100%). These findings are substantiated by the relation between stand density (SDI) and periodic annual increment (PAI). On the B- and C-grade plots of spruce and beech, respectively, SDI was reduced down to 41–91% and 31–83% of the A-grade. When SDI is reduced in young stands, PAI follows a unimodal curve. Norway spruce’s PAI culminates in 109% if SDI is reduced to 59%; European beech’s PAI culminates in 123% when density is reduced to 50%. Whereas Norway spruce’s growth reacts most positively on thinning under poor site conditions and with increment reduction on favourable sites, European beech behaves oppositely. With stand development the culmination point of the unimodal relation moves towards maximum density, so that in older stands PAI follows the increasing pattern, which is the left portion of a unimodal curve. A model is presented which apparently unifies contradictory patterns of stand density–growth reactions by integrating relative stand density, average tree size and site fertility effects, and makes the findings operable for forest management.  相似文献   
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In this study, the pathogenic behavior of PRRSV 13V091 and 13V117, isolated in 2013 from two different Belgian farms with enzootic respiratory problems shortly after weaning in the nursery, were compared with the Belgian strain 07V063 isolated in 2007. Full-length genome sequencing was performed to identify their origin. Twelve weeks-old pigs were inoculated intranasally (IN) with 13V091, 13V117 or 07V063 (9 pigs/group). At 10 days post inoculation (dpi), 4 animals from each group were euthanized and tissues were collected for pathology, virological and serological analysis. 13V091 infection resulted in the highest respiratory disease scores and longest period of fever. Gross lung lesions were more pronounced for 13V091 (13%), than for 13V117 (7%) and 07V063 (11%). The nasal shedding and viremia was also most extensive with 13V091. The 13V091 group showed the highest virus replication in conchae, tonsils and retropharyngeal lymph nodes. 13V117 infection resulted in the lowest virus replication in lymphoid tissues. 13V091 showed higher numbers of sialoadhesin infected cells/mm2 in conchae, tonsils and spleen than 13V117 and 07V063. Neutralizing antibody response with 07V063 was stronger than with 13V091 and 13V117. It can be concluded that (i) 13V091 is a highly pathogenic type 1 subtype 1 PRRSV strain that replicates better than 07V063 and 13V117 and has a strong tropism for sialoadhesin cells and (ii) despite the close genetic relationship between 13V117 and 07V063, 13V117 has an increased nasal replication and shedding, but a decreased replication in lymphoid tissues compared to 07V063.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0166-3) contains supplementary material, which is available to authorized users.  相似文献   
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