Ips acuminatus kills pines in southern Finland

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Muuttaisiko metsälakiehdotus metsäluonnon arvokkaiden elinympäristöjen turvaamisen käytäntöjä?

Tieteen tori: Metsälakiuudistu

Faunistic records of Carabidae and Staphylinidae (Coleoptera) caught by pitfall trapping in western Finnish Lapland

New faunistic records are given based on a total collection of 41 601 Coleoptera, of which 6 364 are Carabidae and 30 414 Staphylinidae. They were collected mostly by pitfall trapping in different forest and mire habitats in western Finnish Lapland. A total of 52 carabid and 186 staphy linid species are reported. Of these, 6 (11 %) and 49 (26 %) species, respectively, were new for the province Lapponia kemensis occidentalis (LkW). Microdota wireni Brundin is reported as new for Finland. Notes on the occurrence and biology of the following species are given: Platynus (Agonum) mannerheimii, Harpalus nigritarsis, Philonthus lederi, Lesteva monticola, Oxypoda operta, Mocyta (A theta) amblystegii, Lomechusa pubicollis and Myllaena hyperborea

Kirjanpainajatuhot Rörstrandin vanhojen metsien suojelualueella sekä ympäröivissä talousmetsissä Sipoossa

TiedonantoTutkimuksen tarkoituksena oli arvioida yhden esimerkkitapauksen avulla todennäköisyyttä sille, että suojelualueelta olisi levinnyt kirjanpainajan aiheuttamia tuhoja ympäröivään talousmetsään. Lisäksi tarkasteltiin tekijöitä, joiden perusteella leviämistodennäköisyyttä voidaan arvioida. Metsä­tuholaki sisältää säädöksiä maanomistajan korvausvelvollisuudesta tällaisissa tilanteissa. Rörstrandin suojelualueelle perustettiin systemaattinen ympyräkoealaverkko, jolta mitattiin neljän edellisen vuoden (2010–2013) aikana kuolleiden kuusten määrä, tuhonaiheuttajat ja kuolleisuuden ajoittuminen. Puuston kuolleisuuden ajoittumisen selvittämisessä pystyttiin lisäksi hyödyntämään alueelle aiemmin vuonna 2002 perustettua pysyvää 4 ha koealaa. Kirjanpainajatuhojen kehittymistä Rörstrandin alueella verrattiin 49 varttuneeseen kuusikkoon Uudenmaan alueella. Tulosten perusteella ei ole todennäköistä, että tuhot olisivat levinneet suojelualueelta naapurimetsään. Tuhot ovat alkaneet hellekesänä 2010 samaan aikaan monissa eri paikoissa Uudellamaalla vanhoissa kuusikoissa, ja tuhot ovat ajoittuneet samalla tavoin kuin Rörstrandin alueella. Rörstrandissa ei havaittu korkeaa kirjanpainajakantaa (runsaasti äskettäin pystyyn kuolleita kuusia) puustomittauksissa 2002 eikä 2008. Elävän puuston mittaukset 2009 ja 2013 osoittavat, että valtaosa kuusten kuolleisuudesta on sattunut välillä 2010–2013 eli samaan aikaan kuin ympäröivissä talousmetsissäkin alkaneet tuhot, ei ennen niitä. Tutkimuksessa kuvattuja menetelmiä voidaan käyttää kirjanpainajan tappamien kuusten kuolinajan määrittämisess

Early-successional saproxylic beetles inhabiting a common host-tree type can be sensitive to the spatiotemporal continuity of their substrate

Intensive forest management has drastically reduced the amount and diversity of dead wood resulting in population decline of saproxylic species. Forestry practices can also disrupt spatiotemporal continuity of dead wood habitats. We studied the effects of stand- and landscape-level densities of host trees on the incidence (proportion of occupied trees) of saproxylic beetles inhabiting recently dead standing Scots pines, a common host-tree type both in natural and managed boreal forests. We compared the occurrence patterns of eight rare specialist and eight common generalist species. Saproxylic beetles were collected from a total of 315 trees in 67 forest stands, including both managed and natural forests, located in three regions which form a gradient in forest-use intensity. Species richness of the entire community at tree and stand level did not respond to the stand- and landscape-level host-tree density. The incidence of six common generalist species did not depend on the stand-level host-tree density, whereas the incidences of four rare specialist species increased with increasing host-tree density. Five out of eight rare specialist species were either significantly less common or absent from the region with the lowest landscape-level density of host trees. We conclude that rare specialist species living in recently dead pines are susceptible to changes in spatiotemporal dynamics of their host trees. To conserve rare early-successional species, it is necessary to ensure continuous input of dying trees by prolonging rotation times in mature forests, regenerating stands using seed-tree cutting and leaving as many permanent retention trees as possible.peerReviewe

Insects inhabiting two old-growth forest polypore species

This paper describes insect communities inhabiting two old-growth forest polypores Amylocystis lapponica and Fomitopsis rosea (Polyporaceae). Basidiocarps of both species were collected from old-growth forests in southern and eastern Finland and Russia. Samples of A. lapponica and F. rosea basidiocarps revealed insect communities of more than 50 species each, including many rare old-growth forest species. Here we report the rearing results and discuss the biology of the beetle Hallomenus sp. (Melandryidae) inhabiting A. lapponica and the beetle Cis dentatus (Cisidae), the moth Agnathosia mendicella (Tineidae) and the fly Elfia cingulata (Tachinidae) inhabiting F. rosea. Distribution maps of C. dentatus and A. mendicella in Finland are given

Faunistics of Coleoptera in subarctic pine forests in Finnish Lapland

The beetle fauna of pine forests was surveyed by window flight trapping in four separate study areas in Pallas-Ounastunturi National Park in Enontekiö Lapland (Le) and Hammastunturi wilderness area in Inari Lapland (Li). The total catch of individuals was 4905, consisting of 195 species. The proportion of species new to the province was 48% in Le and 25% in Li, respectively. Eleven rare species (known at most from 25 localities in Finland) were found. Rarefaction, diversity analyses and similarity indices showed that species richness, relative abundances of species and species composition did not differ significantly between the study areas

Comparison of three trap types in sampling saproxylic beetles living in hollow urban trees

Hollow trees are an important habitat for a large number of saproxylic invertebrates, many of which are rare or threatened. Large old trees occur frequently in cities, but the saproxylic fauna inhabiting these trees has been poorly studied. Sampling in urban areas includes the risk of trap failure due to human interference, which needs to be considered when designing sampling. The aim of our study was to find an efficient trap type for sampling saproxylic beetles in hollow urban trees. We compared the species richness and species composition of saproxylic beetle assemblages between trunk window, aluminium foil tray and pitfall traps placed inside hollow trees in the Helsinki metropolitan area, Finland. A total of 30 traps of each trap type were set in 15 trees. The traps caught a total of 4004 saproxylic beetle individuals belonging to 131 species. Trunk window and aluminium foil traps had similar assemblage and trapping efficiency, and were significantly more efficient than pitfall traps. However, pitfall traps caught certain species more efficiently than the other two trap types. Time spent separating insects from samples was the most laborious work stage. The time increased with increasing sample weight, i.e. the amount of wood mould in the trap. Trunk windows were the most efficient trap type also in terms of saproxylic species and individuals per handling time. We conclude that saproxylic beetle fauna living in hollow urban trees can be efficiently sampled with small trunk window traps or containers placed on the inner walls of hollows.Peer reviewe

Saproxylic beetle assemblages in recently dead Scots pines : How traits modulate species' response to forest management?

Boreal forests have been intensively managed, influencing the spatiotemporal occurrence of dead wood, and leading to changes in saproxylic species assemblages. Some particular traits, such as habitat specialization, can be expected to make species sensitive to alterations in the amount, dynamics and heterogeneity of dead-wood habitats. We compared the saproxylic beetle assemblages of 320 dead standing Scots pines within 52 pine forest stands in three regions in Finland and Russia with contrasting forest-use history. We used the joint species distribution model of Hierarchical Modelling of Species Communities (HMSC) to analyze how the beetle communities respond to alteration of forest structure. We applied scenario simulations to examine relationships between selected species traits and environmental gradients. Our results show that tree-level characteristics were the most important variables shaping the community composition in dead standing pines, but that also the characteristics of the forest stand as well as the larger-scale landscape context affected assemblage composition. Most importantly, managed forest stands and managed forest landscapes had lost species that are specialized in their resource use. The generalist species thriving in managed forest stands and managed forest landscapes were able to utilize dead wood of small diameter and man-made dead wood types, such as cut stumps and logging residues. We conclude that forest management not only reduces the amount of resources for saproxylic beetles locally, but has also landscape-level effects so that the most vulnerable species with specialized resource use and short-lived substrates can be lost also from remnant natural forest patches embedded in managed landscapes.peerReviewe

Stand characteristics and dead wood in urban forests : Potential biodiversity hotspots in managed boreal landscapes

Urban forests are usually not intensively managed and may provide suitable environments for species threatened by production forestry. Thus, urban forests could have the potential of enhancing biodiversity both within cities and at a larger landscape scale. In this study, we investigated stand structures of boreal urban forests to assess them in terms of naturalness and biodiversity conservation potential. We sampled two types of urban spruce-dominated stands: random urban stands as representatives of average urban forests, and valuable urban stands known to host high polypore richness and assumed to represent urban biodiversity hotspots. Urban forests were compared to rural forests with different levels of naturalness. Living and dead trees and cut stumps were measured from all studied stands. Urban forests had generally diverse living tree structures with abundant large-diameter trees. Random urban forests had more dead wood (median 10.1 m(3) ha(-1)) than production forests (2.7 m(3) ha(-1)) but still considerably less than protected, former production forests (53.9 m(3) ha(-1)) or semi-natural forests (115.6 m(3) ha(-1)). On the other hand, valuable urban forests had relatively high median volume of dead wood (88.2 m(3) ha(-1)). We conclude that the combination of diverse stand composition and the presence of old-growth characteristics in boreal urban forests form a strong baseline from which their biodiversity value can be further developed, e.g. by leaving more fallen or cut trees to form dead wood. We propose that urban forests could become significant habitats for biodiversity conservation in the future.Peer reviewe