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Hans Jürgen Bestmann Beate Classen Uwe Kobold Otto Vostrowsky Fred Klingaup 《Journal of pest science》1987,60(2):31-34
The essential oil ofChrysanthemum balsamita L. revealed insecticidal properties when tested againstM. dirhodum aphids. The insecticidal activity was attributed to the presence of pyrethrine I in the oil. By an appropriate testing procedure, the dependence of the activity upon the time of harvesting of the plants was determined. Furthermore, the insecticidal effect of the oil was compared with that of a commercially available pyrethrum preparation. 相似文献
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Hermann Spellmann 《Forstwissenschaftliches Centralblatt》2003,122(4):250-257
Zusammenfassung: Der verbesserte Katalog der gesamteuropäischen Kriterien und Indikatoren einer nachhaltigen Forstwirtschaft ist geeignet, Zustände und Entwicklungen auf verschiedenen Skalenniveaus zu beurteilen. Er repräsentiert die Vielfalt der möglichen Sachziele einer multifunktionalen Forstwirtschaft, die sich in einem hierarchischen Zielsystem strukturieren lassen. Vergleiche zwischen den aktuellen Zuständen und den angestrebten Zielen liefern wichtige Informationen für die überbetriebliche Steuerung. Zur Erreichung der angestrebten Ziele bieten sich meist mehrere Handlungsalternativen an. Diese lassen sich mit Hilfe von Waldwachstumsmodellen auf unterschiedlichen räumlichen und zeitlichen Skalenniveaus überprüfen. Insbesondere Einzelbaummodelle sind geeignet, strategische Entscheidungen für oder gegen bestimmte Bewirtschaftungskonzepte multikriteriell zu unterstützen. Die Verschneidung von Sachdaten mit Lagedaten in einem geographischen Informationssystem erleichtert es, Kompromisse zwischen den Forderungen verschiedener Waldnutzer auf überbetrieblichen Ebenen zu finden. 相似文献
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Hermann Heddergott 《Journal of pest science》1969,42(5):65-74
Zusammenfassung Der Verfasser schildert die gegenwärtige Situation in der Bekämpfung von Schädlingen in deutschen Lebensmittelbetrieben, Er weist auf die Begünstigung mancher Schädlingsarten durch die Technisierung und Rationalisierung der Betriebe hin. Probleme der schriftlichen und persönlichen Beratung sowie die Organisation und Durchführung der Bekämpfung von Lebensmittelschädlingen werden eingehend besprochen, ebenso die wichtigsten Vorbeugungsmaßnahmen gegen die Einschleppung von Schädlingen unter Berücksichtigung der Einrichtung von Sicherheitsschleusen und Bestrahlungsräumen. Die zur Zeit in der Bundesrepublik üblicben Entseuchungsverfahren für ganze Betriebsanlagen werden unter Beschreibung der wichtigsten Begasungsmethoden diskutiert. Besondere Hinweise gelten der Bekämpfung eingeschleppter Schadlinge und der Vernichtung von Nagetieren. Auch die Problematik in der Beurteilung von Reklamationen wird erörtert. Darüber hinaus finden die Bestimmungen des neuen Pflanzenschutzgesetzes sowie der Höchstmengen-Verordnung — Pflanzenschutz — im Hinblick auf die Bekämpfung von Lebensmittelschädlingen besondere Berücksichtigung.
Summary The author describes the present pest control situation in German food processing plants. He refers to the constant spread of some pests favoured by modern food processing techniques and by the rationalization of plants. Problems of advisory work carried out by personal consultation or written information as well as the organization and implementation of pest control are discussed in detail. This applies also to the principal prophylactic measures against an introduction of pests into the plant by the installation of safety sluices and radiation chambers. The disinfection methods for entire plants presently applied in the Federal Republic of Germany and the principal fumigation methods are also being described. Special recommendations are given for the control of the pests introduced and for the eradication of rodents. Furthermore, the problems relating to an assessment of reclamations are being discussed. In view of the control of pests on food special attention is paid to the regulations of the new Plant Protection Act and to the Regulations on the Maximum Quantity of Residues Tolerated on Food (Plant Protection).相似文献
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Anton A. Gasser Julius Diel Kerstin Nielsen Paul Mewes Christof Engels Uwe Franko 《Soil Use and Management》2022,38(1):179-190
Organic amendments are important to sustain soil organic matter (SOM) and soil functions in agricultural soils. Information about the contribution of organic amendments to SOM can be derived from incubation experiments. In this study, data from 72 incubated organic amendments including plant residues, digestates and manure were analysed. The incubation data was compiled from three experimental setups with varying incubation times, soils and incubation temperatures, in which CO2 release was measured continuously. The analysis of the incubation data was performed with an approach relying on conceptual parts of C-TOOL, CCB, Century, ICBM, RothC and Yasso which are all well-approved first-order carbon models that differ in structure and abstraction level. All models are an approximation of reality, whereby each model differs in understanding of the processes involved in soil carbon dynamics. To accumulate the advantages from each model a model ensemble was performed for each substrate. With the ability of each carbon model to compute the distribution of carbon into specific SOM pools a new approach for evaluating organic amendments in terms of humus building efficiency is presented that, depends on the weighted model fit of each ensemble member. Depending on the organic substrate added to the soil, the time course of CO2 release in the incubation studies was predicted with different accuracy by the individual model concepts. Averaging the output of the individual models leads to more robust prediction of SOM dynamics. The EHUM value is easy to interpret and the results are in accordance with the literature. 相似文献
18.
Theodore W. Hermann Fabrice Duponchelle Leandro Castello Karin E. Limburg Luciana A. Pereira Marília Hauser 《水产资源保护:海洋与淡水生态系统》2021,31(12):1206-1220
- Freshwater environments host roughly half of the world’s fish diversity, much of which is concentrated in large, tropical river systems such as the Amazon. Fishes are critical to ecosystem functioning in the Amazon River basin but face increasing human threats. The basic biology of these species, and particularly migratory behaviour, remains poorly studied, in part owing to the difficulty associated with conducting tagging studies in remote tropical regions.
- Otolith microchemistry can circumvent logistical issues and is an increasingly important tool for studying fish life histories. However, this approach is still new in the Amazon, and its potential and limitations to inform fish conservation strategies remain unclear.
- Here, otolith microchemistry studies in the Amazon are reviewed, highlighting current possibilities, and several key factors that limit its use as a conservation tool in the Amazon are discussed. These include the dearth of spatiotemporal elemental data, poor understanding of environment–fish–otolith pathways, and insufficient funding, facilities, and equipment.
- A research initiative is proposed to harness the potential of this technique to support conservation in the Amazon. Key aspects of the proposal include recommendations for internal and external funding, which are critical to acquiring and maintaining technical staff, cutting-edge equipment, and facilities, as well as fostering regular scientific meetings and working groups. Meetings can facilitate a systematic approach to investigating environment–otolith pathways, broadening the chemical baseline for most Amazonian tributaries, and exploring potential valuable elements.
- These outcomes are urgently needed to conserve biodiversity and ecosystem functioning in the Amazon, especially given threats such as widespread hydroelectric damming. The initiative proposed here could make otolith microchemistry an important, cost-effective tool to inform and foster conservation in the Amazon, and act as a template for other imperilled tropical river basins, such as the Mekong and the Congo.
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N C Winder M Hermann G Grünig C Hulliger R Von Fellenberg 《Schweizer Archiv für Tierheilkunde》1990,132(9):505-510
Thirty-nine horses and 3 ponies underwent a thorough respiratory examination and were grouped as follows: healthy (4 horses and 1 pony); mild chronic pulmonary disease (CPD 11 horses); moderate CPD (16 horses and 1 pony); and severe CPD (8 horses and 1 pony). Bronchoalveolar lavage (BAL) fluid collected from all animals and respiratory secretions (RS) obtained from 39 of these animals were evaluated cytologically and the results were compared. It was concluded that cytological examination of either BAL fluid or RS was useful in diagnosing various equine pulmonary diseases. The only advantage that BAL offered over RS sampling was in cases in which there was no RS available in the trachea. In addition, the severity of the CPD did not always correlate with either RS or BAL cytology. 相似文献
20.
HAES Steril 10% is a colloidal plasma expander rarely used in veterinary medicine. In this study HAES was used in clinical cases for the treatment of shock and in a comparative hypervolemic hemodilution study (HAES versus lactated Ringer's solution) using two experimental horses. Injection of a HAES volume equivalent to 10% of estimated blood volume resulted in a highly significant drop in PCV and in a significant drop in total protein concentration. Half live of HAES was approximately two hours. No incompatibility reactions were observed. In man HAES improves microcirculation. Studies in progress may confirm a similar effect in the equine. 相似文献