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Weitere Beobachtungen zur Natur von Insektenviren an Hand von elektronenmikroskopischen Untersuchungen

Zusammenfassung Ausstriche viruserkrankter Fichtengespinstblattwespen (Lyda hypotrophica) und Seidenspinner (Bombyx mori) wurden in mehreren zeitlich aufeinanderfolgenden Intervallen elektronenmikroskopisch untersucht, wobei bei Lyda im zeitlichen Nacheinander Polyeder, Kapseln, winzige Korpuskeln und kolloidale Massen festgestellt werden konnten. Bei in wässeriger Lösung gehaltenen Seidenspinnerpolyedern zeigte sich eine Umbildung namentlich der Randzonen der Polyeder zu kettenförmigen Bildungen, die letzten Endes wieder in längliche kapselförmige Bildungen zerfielen.Unter Xyloleinwirkung ließen sich diese Körperchen zu Umwandlungen bringen, die auf ihren Zusammenhang hinwiesen. Bei Polyedern ließen sich unter Xyloleinfluß ähnlich wie bei den Lärchenwicklerpolyedern Spaltungserscheinungen erzielen, die gleichzeitig mit Vorgängen im Inneren der Polyeder parallel gingen, die an Stadien im Zellkern zur Zeit der Teilung der Zellen erinnerten.     

Ergebnisse weiterer Untersuchungen zur Natur biophysikalischer Umweltverhältnisse and ihrer Wirksamkeit auf Lebensprozesse vonLymantria monacha L. (Lep., Lymantriidae)

Journal of Pest Science - Further investigations on biophysical factors and their effects on Lymantria monacha L. (Lep., Lymantriidae) The results, published in 1973, that “Zones of earth...     

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Global climate change and its impacts on the terrestrial Arctic carbon cycle with special regards to ecosystem components and the greenhouse‐gas balance

The climatic changes on earth may have serious implications for the carbon (C) cycle in the terrestrial Arctic throughout the 21st century. Arctic vegetation takes up carbon dioxide (CO₂) from the atmosphere producing biomass. In a cold and often moist soil environment, dead organic matter is preferentially preserved as soil organic matter (SOM) due to the inhibition of decomposition processes. However, viable soil microbes exhale huge amounts of CO₂ and methane (CH₄) annually. Hence, Arctic ecosystems exhibit annual fluxes of both carbon‐based (CO₂ and CH₄) greenhouse gases (GHGs) that are in an order of magnitude of millions of tons. Rising Arctic temperatures lead to the degradation of much of today's permafrost in the long run. As a result, large quantities of frozen SOM may become available for decomposers, and GHGs that are entrapped in permafrost may be released. At the same time, warming tends to stimulate the growth, development, and reproduction of many Arctic plants, at least transiently. The present northward migration of boreal shrubs and trees into southern tundra areas may be amplified by that, increasing the ecosystems' gross primary production and, thus, their C sequestration. On the other hand, rising temperatures boost SOM decomposition and microbial respiration rates. In general, soil temperature and soil moisture are key environmental variables to control the intensity of aerobic and anaerobic respiration by microbes, and autotrophic respiration by plants. On the basis of published data on Arctic CO₂ and CH₄ fluxes, the calculations on the terrestrial C‐based Arctic GHG balance made in this review reveal a current annual GHG exchange that ranges between a weak storage of ≤ 225 Tg CO₂ equivalent (eq.) y^–1 and a huge release of ≤ 1990 Tg CO₂ eq. y^–1. Hence, the Arctic GHG balance does apparently already contribute positively to the climatic changes at present. Regarding the future, the relative development of the uptake and release of CO₂ and CH₄ by northern ecosystems is fundamental to the overall GHG status of the Arctic under scenarios of continued climate change.     

Initial soil development in lignite ash landfills and settling ponds in Saxony‐Anhalt,Germany

Weathering and initial soil formation was investigated on 5 sites of lignite ash disposal differing in age (5 to 30 years) and methods of disposal (landfills and sluicing to settling ponds). Soils developed on lignite ash derived substrates were characterized by low bulk densities (< 0.85 g cm^—3), high contents of gypsum (maximum 27%) and calcium carbonate (maximum 46%), high pH values (7—9), very high contents of organic carbon (about 20%), and high contents of ammonium oxalate soluble Si, Al, and Fe containing compounds. These features depended on the constitution of the lignite and the burning conditions. As the substrates were initially in disequilibrium with their environmental surroundings, they were subjected to rapid weathering. Typical features were the depletion of gypsum and decarbonatization in the topsoils of the profiles. Furthermore, pedogenic organic carbon became enriched by ruderal vegetation despite low contents of plant available P and K and high pH values. The C : N ratios increased with profile depth, which indicated the input of pedogenic OM with low C : N ratios into topsoils and the predominance of lignite with a wide C : N ratio (> 100) in subsoils.     

Bergmann glial AMPA receptors are required for fine motor coordination

The impact of glial neurotransmitter receptors in vivo is still elusive. In the cerebellum, Bergmann glial (BG) cells express α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors (AMPARs) composed exclusively of GluA1 and/or GluA4 subunits. With the use of conditional gene inactivation, we found that the majority of cerebellar GluA1/A4-type AMPARs are expressed in BG cells. In young mice, deletion of BG AMPARs resulted in retraction of glial appendages from Purkinje cell (PC) synapses, increased amplitude and duration of evoked PC currents, and a delayed formation of glutamatergic synapses. In adult mice, AMPAR inactivation also caused retraction of glial processes. The physiological and structural changes were accompanied by behavioral impairments in fine motor coordination. Thus, BG AMPARs are essential to optimize synaptic integration and cerebellar output function throughout life.     

Hinweise zur Auswirkung biophysikalischer Umweltverhältnisse auf forstschädliche Insekten,untersucht insbesondere anLymantria monacha L.

Zusammenfassung Die Zentren des Schadauftretens verschiedener untersuchter forstschädlicher Insekten dürften nach zahlreichen Testungen Reizzonen umfassen, welche wieder als eine Kombination von elektrischen und magnetischen Feldern und durch diese freigelegte Metalleffekte erscheinen. Untersuchungen zur möglichen Wirksamkeit dieser Komponenten auf Vitalität und Fertilität vonLymantria monacha führten zu folgenden Ergebnissen. Es erscheint möglich, daß innerhalb von Reizzonen Sterblichkeit und Fruchtbarkeit vonLymantria monacha auch von niederfrequenten elektromagnetischen oder auch konstanten magnetischen oder elektrostatischen Feldern beeinflußt werden, die direkt oder auch über die Pflanze auf die Lebenskraft der Nonne von Wirksamkeit sind. Reizzonenbereich und Normalbereich zeigten hinsichtlich der Mortalität der Versuchstiere gegensätzliche Verhältnisse. Die Anfangsmortalität innerhalb von Reizzonen war gegenüber jener der Zuchten im Normalbereich erniedrigt, die Endmortalität vielfach erhöht. Futter aus Normalbereichen setzte in den Reizzonen, Reizzonenfutter im Normalbereich die Sterblichkeit herab und erhöhte im Normalbereich die Fruchtbarkeit. Im Normalbereich mit Normalfutter gezogene Nonnen wiesen die geringsten Zahlen an abgelegten Eiern auf, was sich besonders bei an Pflanzen eingebeutelten Tieren deutlich zeigte. Die wesentlich höhere Fruchtbarkeit von Nonnen an Pflanzen im Reizzonenbereich mag zusammen mit der hier erniedrigten Anfangsmortalität eine Erklärung zum gehäuften Auftreten vonLymantria monacha innerhalb von Reizzonen geben. Freigesetzte Metalleffekte könnten innerhalb von Reizzonen die Sterblichkeit aber auch die Fruchtbarkeit erhöhen.

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Summary The centres of damages by different forest insects, examined in this research, seem to be in zones of Earth radiations (Reizzonen), which again seem to be combinations of magnetic or electric fields and metal effects, set free by them. Examinations for possible influences of these components on vitality and fecundity ofLymantria monacha showed the following results: It seems possible, that inside of zones of earth radiations mortality and fecundity of this butterfly could be directed from magnetic or electric fields also of low frequency or electrostatic, which either directly or indirectly by the nutrients (plants) influence the vital power ofLymantria monacha. Zones of Earth radiations and normal zones showed different conditions in respect of the mortality. Mortality of larvae of first developmental stages inside of zones of Earth radiations was decreased, such of late stages increased contrary to larvae in normal zones. Plant-food of normal zones decreased the mortality of larvae in zones of Earth radiations and food of zones of Earth radiations decreased the mortality of those of normal zones and increased fecundity in the latter cases. Female butterflies reared in normal zones showed the lowest number of developed eggs, especially when reared encaged on living plants (spruce). The essentially higher fecundity ofLymantria monacha reared on plants inside of zones of Earth radiations together with the decreased mortality of first instar larvae there, may give an explantation for the increased population ofLymantria monacha inside of zones of Earth radiations. Metal effects set free inside of zones of Earth radiations could increase there the mortality but also the fecundity.

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Herrn Prof. Dipl.-Ing. Dr. ERWIN SCHIMITSCHEK zum 75. Geburtstag.

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