Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
1997
Forfattere
Erik Christiansen Alf BakkeSammendrag
Availability of defenceless or weakly defended breeding material, e.g. trees felled or damaged by major wind storms, is a necessary requirement for an outbreak of the spruce bark beetle. Water stress is also hypothesised to be an important predisposing factor, although this idea is mostly based on circumstantial observation of a coincidence between dry weather and beetle outbreaks. Whereas a causal relationship may well exist for certain scolytid beetles, experimental evidence is often scarce and in some cases contradictory. We examine information pertaining to population dynamics of the spruce bark beetle Ips typographus in Norway. This includesexperiments to assess effect of drought stress on host tree susceptibility to the beetle’s pathogenic fungal associate, Ceratocystis polonica, andresults from a population monitoring program which has been in operation since 1980. Because drought often coincides with hot weather, one can confuse a direct effect on beetle propagation by hot weather with an indirect effect on insect dynamics through predisposition of the host trees. We conclude that apart from extremely rare cases of severe droughts lasting for a long period of time, direct effects of spring weather on beetle propagation are more likely to affect I. typographus dynamics than are indirect physiological effects working through the host trees.
Forfattere
Perry J. BrownSammendrag
Det er ikke registrert sammendrag
Sammendrag
The subfamily ground midges (Lestremiinae) has been poorly studied in Fennoscandia. Until quite recently (1986) only eight species of this group was known from this area. However, the number of species recorded has increased considerably the few last years. This article surveys new and old records of ground midge from Fennoscandia. The survey is based on a new material collected in 49 localities in various parts of Fennoscandia, and on records in previous publications. A list of altogether 73 species of ground midge is presented, including 25 species which are new to Finland, Norway or Sweden.
Forfattere
Sondre Skatter A.A. DyrsethSammendrag
Det er ikke registrert sammendrag
Forfattere
Jan Mulder E. Matzner J.F. Gallardo Edward TippingSammendrag
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Forfattere
Jan Mulder E. Matzner J.F. Gallardo Edward TippingSammendrag
Det er ikke registrert sammendrag
Forfattere
Michael J. Wingfield T.C. Harrington Halvor SolheimSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Marc H. SchneiderSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag