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Zusammenfassung Die Beobachtungsergebnisse der letzten zwei Jahre zeigen deutlich eine starke Sch?digung der Cinarinen durch ULV-Bek?mpfung. Die Lachniden wurden alle get?tet. Sie blieben zum Gro?teil tot mit dem angesaugten Rüssel an der Wirtspflanze h?ngen. Sie wanderten aber relativ rasch von au?en wieder ein. Auch bei den Physokermes-Schildl?usen war der gro?e Unterschied an gez?hlten L1 zwischen bek?mpft (0,48 L1/Quirl) und unbek?mpft (3,62 L1/Quirl) nach der Aktion auffallend. Für Ameisen erwies sich eine chemische Forstschadlingsbek?mpfung der beobachteten Form als sehr starker Schock, der zumindest für bereits geschw?chte Kolonien letal sein kann. Gerade bei Ameisen sind weitere Beobachtungen in dieser Richtung wichtig, um z. B. festzustellen, wie sich Nestschutz w?hrend der Bek? mpfung (Abdeckung mit Plastikfolie) oder Fütterung w?hrend und nach der Bek?mpfungsaktion auswirkt. Es ist unserer Ansicht nach sicher überlegenswert, auch durch andere Ma?nahmen (z. B. Waldbau, biologische Bek?mpfung mit Viren, Bakterien, Ameisen, V?gel etc.) zu versuchen, Sch?dlings-Kalamit?ten schon von vornherein zu unterbinden. Vor allem ist es fragwürdig, nur blo?e Zuwachsverluste durch chemische Bek?mpfung hintanzuhalten. Auch vom Standpunkt der Bienenzucht ist die Erhaltung ein natürlicher, den stand?rtlichen Gegebenheiten entsprechender Waldaufbau und eine bewu?t durchgeführte Waldhygiene anzustreben, um so Massenvermehrungen forstsch?dlicher Insekten hintanzuhalten. Wie eingangs betont wurde, ist heute das Gebiet der landwirtschaftlichen Nutzung für die Bienen ein „ Hungerland” geworden. Um so mehr und um so wichtiger ist die Waldbienentracht, um genügend einheimischen Honig zu gewinnen, um die fast unbegrenzte Nachfrage danach decken zu k?nnen und auch vom Honigimport frei zu sein. Zu betonen ist, da? die Bienenzucht ja nicht allein vom Standpunkt des Imkers aus betrachtet werden darf, sondern da? der Biene auch als Blütenbest?uberin gro?e ?kologische und wirtschaftliche Bedeutung zukommt.
Summary The use of insecticides and herbicides in agricultural regions has impaired living and foraging conditions for honeybees, and consequently, the honeydew flow of the forest has become increasingly important in many parts of the country. At present pest control is also being carried out over wide forest areas. In the cases described the preparation Malathion was sprayed by aircraft in the form of a mist (ULV-control). Malathion, which penetrates the sap-conducting vessels of plants, is ingested by insects whatever their manner of feeding. Its advantage for the environment is that the poison is active only for a few days. The present investigations were undertaken in 3 different parts of Austria where pest control was being applied. The aim was to establish its effect on innocuous honeydew producers and ants. In each case thousands of cinarines were counted inside and outside the area before spraying, and shortly afterwards, the branches having previously been marked, the mortality was ascertained. The observations (1972 and 1973) clearly showed that ULV-control is extremely harmful toCinara spp. All the lachnids were killed off, most of them remaining attached to the host plant by their probosces. If, however, the sprayed area is not too extensive it is quickly recolonized from outside, as was evident in the Weinburger Wald area in 1973. The effect of spraying onPhysokermes spp. was observed in detail for the first time in 1973. Even this single observation revealed after treatment a great discrepancy in the number of L1 counted: sprayed: 0.48 L1/whorl, not sprayed: 3.62 L1/whorl. If this result is confirmed by further observations there can be no doubt about the considerable deleterious effect of the treatment. In the case of ants chemical pest control in the form observed constitutes a very severe shock, which can destroy colonies for weaks. Covering these with plastic foil or feeding before and after spraying might prove a remedy.


Dr. Franz Berger, Biologische Station Lunz am See, zum 70 Geburtstag gewidmet

Vortrag auf dem 4. Südtiroler Entomologentag, Sept. 1973 in Dietenheim  相似文献   

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Summary By summing up the scattered evidence from the literature it is to note that it exists a complete chain of evidence to prove that flies have the capacity to transmit poliomyelitis virus. For it has been observed that the faecal material of infected persons contains the virus, that the flies visit the faeces and are able to pick up the virus, that flies caught in natural conditions harbour the virus, that the virus maintains for three weeks in the fly, that the fly is capable of supporting the multiplication of the virus, that the excrement of the flies contains the virus, that flies visit human food and deposit their excrement in it and that such food eaten by apes results in infection. Some facts support the hypothesis that besides faecal material, carcasses may also play a role as a source of viruses for flies. It is also possible that flies can infect man not only by the oral route but also via wounds. It has been stated that infection via wounds causes paralysis more readily than oral infection. Some facts support the idea that the higher incidence of paralyses in poliomyelitis occurring in the temperate climates should depend on the frequent infection of wounds of susceptible persons by blowflies, which are predominating in the fly fauna of more northern areas. In warmer climates, where houseflies are predominating, the virus is transmitted effectively by flies to foodstuffs. The infection reaches thus the man by the oral route and results most often in a nonparalytic disease.There has been accumulated some evidence for the wiev that fly transmission of poliomyelitis occurs to such a degree that it is of epidemiological significance. It has been observed four times thatLucilia illustris and some other blowflies of this genus has shown a much greater abundance during epidemic years for poliomyelitis than during nonepidemic years. It has also been shown that poliomyelitis occurs significantly later in the southern coastal area of Finland, where the very late flyingLucilia sericata (the species from which poliomyelitis viruses have most often been isolated) occurs, than outside this area. In Finland the outbreak of poliomyelitis epidemics is preceded for about 1–2 weeks by an increase of the abundance of this blowfly and by the ovipositional periods of most other blowflies of the genusLucilia. The occurrence of cloudy days, which are unfavourable for the activity of blowflies, shows a weak positive correlation with the incidence of poliomyelitis. This fact is possibly an indication of the invalidity of the hypothesis of fly transmission of poliomyelitis, but it is also possible that the inhibition of normal ovipositional activity may drive the blowflies to the surface of homoiothermic animals or to human dwellings. Statistics on the changes of theLucilia fauna during the 20th century in Finland show that an increase in their dominance coincided, with the increase in the incidence of paralytic poliomyelitis and the rise in the summer temperatures. Especially the expansion ofLucilia sericata to south Finland coincided clearly with the increase in the incidence of paralytic poliomyelitis. Some facts speak for the comprehension that this highly synanthropic species should be responsible for the fact that the incidence of poliomyelitis is in Finland higher in great cities than in small cities or rural districts. Studies on the effect of fly abatement in poliomyelitis control have remained inconclusive.  相似文献   

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In einer Reihe älterer und neuerer Veröffentlichungen habe ich die forstlichen Verhältnisse in der Oberlausitz in ihrer geschichtlichen Entwicklung und der Struktur, die sie zu Beginn des letzten Weltkrieges hatte, untersucht. Wenn ich in der vorliegenden Arbeit die geschichtliche Entwicklung der Ertragsregelung einer Betrachtung unterziehe, so bitte ich den speziell interessierten Leser, die bisher erschienenen Abhandlungen und Kapitel zu berücksichtigen:
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    Jagdliches aus der Oberlausitz. — Thar. Forstl. Jahrb. 89, 1938, S. 758–769.  相似文献   

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