Search results for "lehtipuut"
showing 4 items of 4 documents
Morphological traits predict host-tree specialization in wood-inhabiting fungal communities
2020
Tree species is one of the most important determinants of wood-inhabiting fungal community composition, yet its relationship with fungal reproductive and dispersal traits remains poorly understood. We studied fungal communities (total of 657 species) inhabiting broadleaved and coniferous dead wood (total of 192 logs) in 12 semi-natural boreal forests. We utilized a trait-based hierarchical joint species distribution model to examine how the relationship between dead wood quality and species occurrence correlates with reproductive and dispersal morphological traits. Broadleaved trees had higher species richness than conifers, due to discomycetoids and pyrenomycetoids specializing in them. Re…
Lignoselluloosan happamassa esikäsittelyssä poistuvat hiilihydraatit
2017
Tämän lisensiaattitutkielman kirjallisessa osassa esitettiin kuvaus biomassoista, (ligno- selluloosamateriaalit) ja niihin pohjautuvien jalostettujen polttoaineiden tuotannon haasteista ja kustannuksta sekä tarkasteltiin biomassaraaka-aineiden esikäsittelymene- telmiä. Tarkastelun pohjana oli Suomen kasvuoloissa yleisimpien lingoselluloosa- materiaalien, havu- ja lehtipuun sekä ruokohelpin, soveltuminen bioetanolituotantoon niin integroituna perinteisen sellutehtaan yhteyteen kuin myös omana erillisenä tuo- tantonaan. Tutkielman kokeellisessa osassa analysoitiin eri esikäsittelymenetelmien, laimean ja väkevän rikkihappokäsittelyn sekä vesikäsittelyn vaikutusta tuotetun hydrolysaatin koostum…
Browsing hinders the regeneration of broadleaved trees in uneven-aged forest management in southern Finland
2020
Uneven-aged forest management has attained increasing popularity. It may benefit biodiversity, buffer against pests and abiotic damages, decrease runoff from clearcuts and improve recreational values. We studied how gap cuttings and single-tree selection cuttings influence browsing damage in spruce-dominated forests in south-central Finland. Overall, browsing damage was especially frequent in aspen and rowan, but also in birch. The larger the basal area left in harvesting, the lower the browsing pressure on birch and rowan; neither the harvesting method nor the seedling density had an independent effect on browsing damage. Although larger tree retention levels may reduce browsing damage, th…
Managing conservation values of protected sites: How to maintain deciduous trees in white-backed woodpecker territories
2020
Successional and other temporal habitat changes may also affect conservation areas and reduce their conservation value. Active management to promote vulnerable habitat features may be an effective, but controversial, solution. Old deciduous trees and deciduous dead wood in boreal forest reserves are examples of habitat features that may be lost during succession, yet several threatened species, including the white-backed woodpecker (Dendrocopos leucotos), are dependent on them. Encroaching spruce have been removed from white-backed woodpecker territories to promote the regeneration of deciduous trees and to preserve habitat quality, although the efficiency of this treatment is unclear. In t…