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398 Uppsatser om Exotic trees - Sida 12 av 27
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.
Växter vid havet :
Detta examensarbete behandlar växter som trivs vid havet. Arbetet baseras på frågan vilka växter som tål ett vindpinat och utsatt läge?
Arbetet beskriver vad man skall tänka på när man börjar planera en trädgård vid havet. I arbetet har jag tagit upp vilka träd och perenner som man kan använda sig av när man skall skapa en trädgård vid havet.
Syftet med arbetet är att man skall kunna använda sig av mitt arbete när man åker till plantskolan för att inhandla växter.
Barns kunskaper om djurarter : Kan kunskaperna skilja beroende på vart man bor?
This study is about differences in knowledge regarding animals. In the study five year old preschool children from a city were compared to five year old preschool children in the suburbs with multicultural background. The study is also about where children´s knowledge about animals comes from and how educators can make a positive difference. To find this out standardized interviews was used on 23 children from four different preschools, two preschools in the suburbs with 15 children and two preschools in the city with 13 children. A survey was sent out to the educators within these preschools to gather background information on what the children do regarding animals.
Utveckling av en diameterklassmodell för grandominerade bestånd i Sverige :
Growth models are very useful tools for forestry to predict growth and yield. With growth models and optimising tools you can manage forest stands in a way that maximize benefit and income. There are three major types of growth models. Stand models; stage structured models and single-tree models. The most advanced models give the most accurate forecasts.
Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project
The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations.
The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.
Utvärdering av en subjektiv metod för att skatta mängden trädbiomassa längs vägkanter :
Forest biomass is becoming an increasingly important source of renewable energy, and thereby the demand is increasing. There is currently 213 000 km of forest roads in Sweden that could be suitable for biomass harvesting. Harvest of biomass along forest roads both provides biomass and maintains the quality of the roads. Currently, the volume of biomass along roads can only be assessed post harvest, chipping and industry deliverance.
As the decision of whether or not to harvest should preferably be based on more than experience, the TJ-method has been proposed. The TJ-method is a subjective method to quickly determine the dry matter quantity with the assessment being conducted from the roadside.
Rumslig fördelning av grov gammal tall i Uppsala stad med tallticka som indikator på höga naturvärden :
Fragmentation and reduction of forest area is a threat for many forest species and their habitat. Deficiencies in forest quality, such as lack of dead wood and old trees, are one explanation of the threat. The most important action to prevent the continued loss of forest types is to protect forest, but also to restore and to create areas that not previously had high nature values. Hence one of the key strategic roles for Fritid- och Naturkontoret, Uppsala municipality, is to monitor biodiversity in the context of urban planning.
The majority of the Uppsala municipality residents live in urban areas and most of them spend some of their spare time in natural areas in cities and their immediate surroundings. Exploitation in and around Uppsala is high, but it is important that there is enough nature close to houses to meet the residents? needs of recreation.
Näsbyholm - parken och de närmaste omgivningarna ur ett historiskt och nutida perspektiv
The goal of this work has been to search historical materials, to identify the park's historical development, to prepare proposals on measures and that work should be the basis for further research. The aim has been to train us in searching for and use of materials and to gain an understanding of the process of work with older plants. In the process we have sought and found materials in archives, through literary and oral sources, and email
contacts.
Because of its excellent location perched on an islet in the low landscape Näsbyholm was long a fortress. The old castle on Näsbyholm was from the late 1400s but the site was
fortified much earlier. The islet was at this time completely surrounded by water and there was a drawbridge over the narrow waterline.
The owners are liable since the late 1200s.
Flygbildsanalys av trädskiktets status efter brand : en metodstudie
During the past years fire has been identified as an important factor for nature conservation in the forest landscape. To accurately quantify the size of a burnt area is obviously important, but also to quantify the degree of fire damage to the tree canopy. Such data are important for assessing the conservation value, and to support planning and management of the burned area in the future.
I have examined how to estimate the status of tree crowns after fire from interpretation of aerial photographs. This is possible because fire changes the structure of tree crowns and this influences the colours in aerial photographs by spectral reflection.
Included in the study are four areas, three of which burned in 2005 and one in 2006.
Buskröjning längs skogsbilvägar : en produktivitetsstudie av två kättingslagor
To regularly remove woody vegetation along the roadside of forest roads is an important part of the road maintenance, since the vegetation binds moisture in the road side and, thus, the removal makes the road drying faster with results in improved bearing capacity. Vegetation removal also makes it easier to upgrade the road by material recycling from the ditch and, moreover, the visibility along the road is maintained.The aim of the study was to evaluate what type of chain flail is the best and most cost-effective for removal of different kind of woody vegetation along forest roadsides.Time studies were made on two chain flails when removing woody vegetation in three different classes; easy-, middle- and heavy shrub removal. The studied flails were one light and rather simple flail named Optimal M160 and a heavier and more advanced flail named Slagkraft H210. The removal was made according to Holmen Skogs? specification and the quality of the cleaning was measured by objective belt inventory.The productivity was higher with the heavy flail within all cleaning classes.
Hypertrophic osteoarthropathy in wildlife : and a review of suggested pathogeneses
In this essay suggested pathogenesis of secondary hypertrophic osteoarthropathy (HOA) is reviewed. HOA, characterized by; periostitis, periosteal proliferation of tubular bones and arthritis can develop due to many different underlying diseases. The syndrome is most commonly seen with intra-thoracic malignancy or chronic pulmonary infections. HOA has previously mainly been described in humans and various domesticated species. More recently, through wildlife disease monitoring, cases have also been found among wild animals.
Kronandelsrelaskopering, en ny metod för att fastställa gallringsbehov?
In today´s forestry, assessments of needs for thinning are based on basal area measurements. This is an indirect measurement. The approach and the developed assessment tables are based on an assumed production forest, which implies that management proposals in stands that deviate from the basic model may be misleading. Since Walter Bitterlich in 1948 launched the idea of the relascope, several modifications have been developed for different purposes. In common is that all are based on a certain angle measurement principle.
Överlevnad och tillväxt för Douglasgran i södra Sverige
After the two big hurricanes called ?Gudrun? (2005) and ?Per? (2007) in the south of Sweden, some landowners planted Douglas fir instead of the traditional Norway spruce and Scots pine. They did it for different reasons. Some of them spreading their "risk", others because they wanted better growth or to obtain a more storm-resistant stand and trees more protected against rot. In this study, survival and growth were examined on Douglas fir in 21 different locations, owned by private landowners in southern Sweden.
Heterogenitet i skogsbestånd : faktorer av betydelse för artrikedom och förekomst av småfåglar
Denna studie undersökte hur heterogenitet i skogsbestånd samt omgivningsfaktorerna träddiameter, variation i träddiameter, död ved och lövinslag påverkar förekomsten av 18 skogsfågelarter i södra Sverige. Fågelinventeringen utfördes med hjälp av linjetaxering längs 100 meter långa transekter. Omgivningsfaktorerna mättes i varje transekt i fem provcirklar med diametern 10 meter. Analysen av träddiameter visade att det främst var diameter på barrträd, men inte på lövträd som inverkade på förekomsten av fåglarna. Sambanden mellan diameter på barrträd och totalt antal fågelarter var övervägande negativa vid 0-30 centimeter i diameter och övervägande positiva vid 30-80 centimeter i diameter.
Fågelbär (Prunus avium L.) - överlevnad, höjdutveckling och skador i unga planteringar på småländska höglandet :
Plant survival, plant damage and height growth were studied in nine wild cherry (Prunus avium L.) plantations in southern Sweden established between 2000 and 2002. All stands were located to the county of Småland. The survey was conducted during May and June in 2007. During the survey the height, diameter and quality of the cherry trees were recorded. In one stand, red ? berried Elder (Sambucus racemosa L.) was a dominant species.