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491 Uppsatser om Dead trees - Sida 1 av 33
Mortalitet av bok i Biskopstorp och Frodeparken naturreservat, Halland :
The aim with this study was to investigate mortality in older respectively younger beech
stands (Fagus sylvatica), the different types of dead wood in the forest and the availability of coarse woody debris (CWD). The research was carried out in previously managed and seminatural stands in Biskopstorp and Frodeparken, located north of Halinstad in Halland,Sweden. Data were collected from 22 stands with at least 50 % beech and with a minimum age of 5 1 years, ranging in size from 0,67 to 19,9 ha. A transect was placed in each stand, in which the diaineter on both dead and living trees with a minimum diameter of 50 mm was recorded. On seven to 13 Dead trees, depending on the size of each stand, decomposition stage, primary and secondary cause of death, amount of fungi and the type of the dead wood was noted.
Trädens utveckling efter att de har lämnats som naturhänsyn : tillväxt, mortalitet och strukturell förändring 6-18 år efter avverkning
Today green tree retention, together with leaving dead wood, is a common practice with the aim to reduce negative impacts on biodiversity and environment due to clear-felling. To better understand whether this conservation practice also makes a long-term difference, it is important to know what happens to these trees after harvest. Few studies have made an assessment of what happens to retention trees over a longer time period. In this study I inventoried retention trees that were left at clear-cuts six, twelve and eighteen years ago. I carried out a re-inventory of 57 retention patches (divided into free-standing tree groups, small swamp forests and edge zones) and free standing Dead trees, spread over 25 previous clear-cuts in central Sweden.
Vedlevande lavar på döda grenar på levande träd i produktionsskog
Saproxylic lichens in managed forests have less substrate available than in unmanaged forests due to the shortage of dead wood. However, a suitable substrate for these lichens could be dead branches on living trees. To this date, there has not been any systematically collected data about theabundance of dead branches on living trees and the lichens growing on these branches in managed forests. The aim of this study was to see where dead branches were located on living trees of Pinus sylvestris and Picea abies, how large the surface area of these branches was and what lichens grewof wood on these branches. The study was made in Finspång, Sweden, where 11 forest stands of P.sylvestris and P.
Liv i d?d ved: En unders?kning av f?rh?llningss?tt till d?d ved p? ?ppeltr?d i tr?dg?rdshandb?cker och bland yrkesverksamma tr?dbesk?rare
In this essay, several factors in apple tree care (specifically in relation to whether dead wood
should be kept or removed) are highlighted for example, aesthetics and biodiversity.
To present some background, the essay begins by introducing some previous literature on
dead wood. This leads into how dead wood is treated within forestry. Next, previous research
on dead wood in fruit trees is mentioned. Cultural and historical management methods are
also highlighted.
Lodgepole pine - stability after thinning
SCA has today almost 300 000 hectares of their forest land planted with lodgepole pine(Pinus contorta var. latifolia). Due to initial extensive planting in the 1970ies the area oflodgepole pine forests in the thinning age has grown rapidly from the end of the 1990ies.During the years 1996-2005 first commercial thinning of lodgepole pine at SCA took place.The goal of the hereby presented study was to investigate the growth and stability in thosefirstly-thinned lodgepole pine stands a few years after thinning. Furthermore, the objectivewas to investigate the relationship between stand stability and different stand parameters.Additionally, lodgepole pine stem quality was estimated.The study is mainly based on the data collected during an inventory project carried out atSCA in 2008. Altogether 91 lodgepole pine stands in northern Sweden were measured afterthe first thinning.
Hur påverkar naturvårdsåtgärder mängden av vedlevande insekter : Manuellt dödade träd vs självdöda
Today?s forest managers implement a large number of methods to increase the amount of dead wood in Swedish forests. They use everything from high cutting of trees to girdling trees and burning forests. However, implementation of these measures without proper knowledge of their consequences is a common problem. This study has been performed to increase knowledge about two of these measures, girdling and high cutting, and how these actions affect the number of wood-living insects living on Dead trees.
Betydelse av lövinslag, död ved och variation i träddiameter för artrikedomen hos småfåglar
Forest management contributes to the changes in forest structure by turning heterogenous forests of varied age into homogenous forests of similar age and thus affect bird species depending on different structures or habitats which are lost during forestry. In this report, a study was made to investigate how the amount of decidious trees, dead wood and variation in tree diameter affect bird diversity. The purpose of this study was to be able to give forest management guidelines to increase bird diversity. This study was conducted by investigating 65 transects in forests of different structure south of Linköping, Sweden. Along the 65 transects, birds were inventoried as well as the vegetation.
Dead Reckoning i bilspel
Denna rapport handlar om dead reckoning i bilspel. En rad nätverkstekniker tas upp grundligt, och fem olika versioner av dead reckoning implementeras, provkörs och utvärderas. En nätverkssimulator har skapats för att provköra algoritmerna i och datan från dessa provkörningar ligger till grunden för en analys av de olika implementationerna. De testas bland annat mot konsistens och bandbreddsåtgång. SimBins GTR Evolution har använts för att spela in loppen, och rapporten inriktar sig på hur dead reckoning fungerar i detta spel..
Gamla tallars betydelse för biologisk mångfald på Gotland
Modern methods for managing pine (Pinus sylvestris) create homogenized forests. This decreases nature?s potential for biodiversity and might threaten species in need of different types of milieu. The main purpose of this study was to investigate how important older pine trees are for biodiversity. In the Hall-Hangvar Reserve in the north-west part of Gotland, insects collected from traps showed that more species were found in old or Dead trees compared to younger pine trees.
Naturhänsyn vid föryngringsavverkningar : En jämförelse mellan certifierade och o-certifierade hyggen
A growing number of Swedish forest owners are choosing to certify their forestry. However, there appears to be a lack of field surveys which describe differences between certified and non-certified forests concerning the degree of completed environmental considerations. In order to know to what extent certified forests contribute towards improved environmental consideration, we need studies on how large the difference is in relation to non-certified forests.Differences between certified and non-certified forest clearings were quantified through an inventory of the number of retention trees, Dead trees and snags. The result showed that the retained number of the investigated parameters varied greatly between individual clearings, regardless of certification status. However, the results suggested that the certified clearings had an average higher incidence ofthe investigated parameters.
Död ved i gallrad skog och nyckelbiotoper : en jämförelse av habitatkvaliteter för vedlevande lavar och mossor
A high amount of dead wood is one of the most important prerequisites for high biodiversity on forest land in Sweden. Dead wood is most abundant in young forests, thinned forests, woodland key habitats and protected forest land. In old-growth forests most of the dead wood consists of logs and snags, whilst in managed forests a huge proportion of dead wood is made up of logging residues like stumps and FWD, fine woody debris (< 10 cm diameter). All these different types of dead wood may serve as substrates for epixylic bryophytes and lichens. However, few studies have been conducted on the relative importance of these different fractions of dead wood for the occurrence of bryophytes and lichens, especially when considering dead wood on thinned forest land.
Trädföryngring i låga gropar uppkomna vid brand i boreal naturskog :
This study was conducted in the "Kåtaberget" forest reserve in Västerbotten in the summer of 1999. In the summer of 1995, a prescribed burning was performed in the reserve. In some places where coarse dry woody debris (logs and stumps) was present, the fire consumed the wood, as well as parts of the humus layer, creating deep-burned patches. The low intensity ground fire also created dead woody debris by burning off living trees with open fire scars, as well as standing Dead trees.
In this study, the post-fire tree seedling establishment was examined, with special attention given to the former presence of woody debris. The study also includes a survey of the areal extent of deep-burned patches, as well as an examination of tree seedling establishment in these patches, compared to other burnt ground.
Underröjning i förstagallring :
This report is a thesis work for a B.Sc. in Forestry exam at the School for Forest Engineers,
SLU. The work was an assignment from Sydved and the aim of the work was to investigate the economical output of removing understorey trees before first thinning.
Four treatments were studied.
- no cleaning before thinning
- cleaning of all trees less than DBH 5 cm before thinning
- cleaning of all trees less than DBH 7 cm before thinning
- cleaning of all trees less then DBH 9 cm before thinning
The result shows a decrease of the cost per m3 for the harvester with about 38% if all trees less than DBH 9 cm was cleaned before thinning compared with the un-cleaned area. At the same time the total net revenue increases with about 22%.
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Naturhänsyn på certifierade privata skogsfastigheter : en jämförelse i praktiken mellan FSC och PEFC i Sydsverige
Nature conservation on certified small private forest owners- a comparison
between the two certification systems FSC and PEFC in southern Sweden
Today two different certification systems are used in Sweden to certify forest, FSC (Forest Stewardship Council) and PEFC (Pan European Forest Certification). During the last years certification of forests in general and different certification systems have frequently been debated. FSC is a globally widespread system and about 10 million ha out of 23 million ha Swedish forest is FSC-certified. The FSC-standard is mainly used by major forest companies and to some extent also by smaller private forest owners. PEFC is a European system and about 2 million ha Swedish forests is PEFC-certified today.
Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna
In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time.
The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.