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371 Uppsatser om Deciduous trees - Sida 9 av 25

Jordbruksverkets nya definition av betesmark : Effekter och reaktioner hos lantbrukarna. Intervjuundersökningar från Skåne och Örebro län.

Wooded pastures are common in the agricultural landscape in Sweden, often rich in naturaland cultural values. It is not a well confined biotope but consist of a semi-open landscapewith a complex pattern and wide variation of tree and shrub coverage. The values in thewooded pastures have been created through a long history of management.One major threat to wooded pastures is ceasing management. Yearly and intensive grazinghas been demanded for several years in order to receive economical support. At the sametime trees and bushes have often been regarded as vegetal invasion.

Kan biologisk mångfald ökas i ett avsatt skogsområde? : skötselplan för Storskogsberget på Holmen skogs marker, distrikt Umeå

The biodiversity of the Swedish forest has degenerated since the beginning of the 19th century when fire suppression and large scale logging first occurred. Together with a changed land use, these actions today have had a negative influence on many forest dwelling species, due to gradual reduction of natural processes, successions and different structures from the forest ecosystem. The Swedish Forest Act, together with different environment certifications, have today encouraged private persons and forest companies, among them Holmen Skog, to work actively to improve nature conservation. The aim of this study was to, by field inventories of already existing nature values, literature studies, recommendations from scientific reports and ecological gap analysis as a basis, make a management plan, for a non-production area, to conserve or improve the prerequisites for biodiversity. ?Storskogsberget? is located in the coastal area of Västerbotten County, 35 km from the city of Umeå.

Factors affecting bark-stripping by red deer (Cervus elaphus) : the importance of landscape structure and forage availability

Bark-stripping by red deer (Cervus elaphus) cause extensive damage to economically valuable spruce trees (Picea abies) in Swedish forests. The underlying causes for bark-stripping are not fully understood, and the frequency and severity of damage unpredictably differ between regions. In this study, I investigated if landscape structure (e.g. agricultural dominated landscape opposed to forest dominated landscape), forage availability, population density and disturbance (e.g. roads and settlements) affect bark-stripping frequency.

Datering av röta i hålekar :

I have chosen in this work to examine which factors are affecting the artificially creation of a tree cavity containing decomposed wood. The purpose of the work is to find out which factors are affecting the most when a tree cavity is created, and to apply these results when you artificially try to create a tree cavity. The need to create tree cavities comes from the situation where many tree cavity living beetles finds themselves today. When existing trees are to pass out there will be no suitable inheritors yet. The work was initially to focus on cavities created from cut branches.

Effekterna av urbanisering, barksprickedjup och solexponering på lavfloran i sydöstra Sverige

Studies have shown that air pollution, as well as bark fissure depth and sun exposure of a tree can have an effect on lichen growth as well as abundance of lichen species. The aim of this study was to find out the relative importance of these factors. 211 oaks in south eastern Sweden were surveyed for presence of 17 lichen species, as well as the total number of lichen species. Half of the trees were situated in urban areas and half in the countryside. For each tree the bark fissure depth was measured and the sun exposure of the trunk was estimated.

Hur en ökad marktemperatur påverkar fotosyntes och markrespiration i en boreal skog

During the year of 2008, a powerful earthquake hit the southern part of Iceland, which changed the geothermal conditions in the area around the city of Hveragerdi. Elevated soil temperatures in a nearby forest plantation have contributed to a unique opportunity for researchers to study how an increased soil temperature affects the boreal forest ecosystem, something that partly can be connected to the climate changes which are happening today. The boreal forest is representing a carbon sink and a buffert for the emissions that occurs. Changes in this ecosystem will for that reason contribute to major impact for the global carbon cycle. To study the impact of how elevated soil temperatures affects different processes in a plantation of Sitka spruce, studies were made on the photosynthesis of the trees and the respiration from the soil.

Skötselåtgärder vid nyetablering av skyddszoner vid bäckar i södra Värmland :

Buffer zones play an important role for the water quality in our watercourses. When harvesting a forest close to a watercourse a buffer zone should be left. When it's not left, it will lead to radical changes in the environment for the water organisms. The overall purpose of this thesis was to illuminate the production- and environmental thinking when establishing new buffer zones in south of Värmland. The partials goals were to determine choice of tree species, ways of regenerate, occurrence of soil scarification and the occurrence of machine tracks in newly established buffer zones.

Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes

Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.

Skolträdgården i folkskolans miljö på Gotland : med exempel från Bunge- och Stenkumla skola

The thesis explores the phenomena of historic school gardens connected to elementary schools on Gotland, Sweden. Gotland had the highest percentage of school gardens connected to the elementary schools in Sweden, and by investigating this area much can be learned about the Swedish conditions. The study focus on the period in time when the school gardens were most frequent and used the most, to the point in time when they start losing ground. To bridge over the past to the present the thesis also investigates what is left and play with the thought of possible ways to treat the remains. The main question for the thesis is: How could a school garden on Gotland be constructed and be used 1907 ? 1947?And a follow up question is: What could still be there today and how can/should the remains be treated and conserved? The thesis begin with an overview look at the school gardens of Sweden, closes in with on Gotland and completes with a deeper investigation of two examples of school gardens; Bunge and Stenkumla elementary schools.

Kastanjemalen Cameraria ohridella : livscykel och utbredning i Sverige 2006

Cameraria ohridella, the chest-nut leaf miner, is a new pest in Sweden. These moths make leaf mines on chest-nut trees, preferably on Aesculus hippocastanum, which results in brown blotches on the foliage and early loss of leaves. Since the first observation in Macedonia in 1985 it has spread rapidly through Europe. The moth arrived in Sweden in 2003 when it was observed in Malmö and surrounding areas. In this paper a literature study describes the morphology and life cycle of the chest-nut leaf miner. Further more a test with pheromone traps examining the number of generations in Sweden is shown.

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.

Produktivitet och lönsamhet vid skörd av skogsbränsle i klen björkgallring :

The aim of the study was to compare productivity in first thinning of birch stands, when either energy- or pulpwood was harvested. The systems total profitability was also compared by including forwarding and chipping costs. A Gremo 950 HPVR harvester was used and the same driver was used under the entire study. During the pulpwood harvest a Logmax 4000b harvester head was used and a feller buncher head made by Silvatec was used during the energy wood harvest. Six study unit pairs were located in a birch dominated stand outside Ängelholm in Skåne.

GIS-modellering av habitat för vitryggig hackspett (Dendrocopos leucotos) som hjälpmedel i naturvårdsplanering på landskapsnivå :

The white-backed woodpecker is a forest bird being critically endangered in Sweden. The species is dependent on older forests rich in Deciduous trees and dead wood. The main problem for the survival of this species is present shortage of habitat. Conservation work on this umbrella species is at present focused on finding remaining or emerging habitat networks. Large areas are scrutinized in search for suitable habitats to be protected or managed for the species sake.

Ekologisk landskapsplan för fastigheten Götebo 1:5 :

This thesis constitutes a long term (100 year) ecological landscape management plan for the estate Götebo 1:5. The estate is situated close to Gothenburg and is owned by Skogssällskapet. The planning has been made by dividing the estate into different areas (zones). In each zone one of the goals nature conservation, recreation or economical yield has been prioritized. Nature conservation is one of the main goals for the forest management plan.

Att restaurera forna tiders beståndsstruktur : ett exempel från Jämtgaveln

In Sweden today so-called "prescribed nature conservation burning" is performed due to the change in silvicultural law, certification and an increased knowledge regarding the field of fire in the forest landscape. The aim is to re-create structures and qualities made by the fire regimes of the past, though on a much smaller geographical scale. The structures and qualities to be re-created are for example broad leaf stands, trees with large diameter, heterogeneous stands regarding variables such as age and diameter. If we increase our knowledge of the constitution of forests characterized by fire, then we will be able to set goals for what achievements to reach both on landscape scale and stand scale. The aim of this paper is to try to describe how a stand from the past was composed regarding mainly the spatial arrangement and compare it with the stand of today in the same place. This to be done by using relict material, that is stumps and dead standing trees.

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