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745 Uppsatser om Threatened species - Sida 18 av 50
Granföryngring på tallmark, hur ofta förekommer det? :
This survey was made during the summer of 2004 and the spring of 2005, on commission
from the National Board of Forestry.
The aim of this report was to investigate how often Norway spruce (Picea abies L. Karst), is planted on poor Scotch pine (Pinus Silvestries) sites and if it affects the yield of Norway spruce? In order to investigate this, data from 29 stands witch had a lower site index than T24 was collected. The investigated stands were situated in the southern-eastern Sweden. In 20 plots in each stand, the highest tree, age, number of seedlings, site index and tree species per stand were measured.
Poppel - en möjlighet i norra Sverige?
The countries in the European Union have agreed to increase their percentage renewable energy sources to 20 %. To reach this goal an increase of biomass production needs to be made. One way of achieving this is by using nonnative species.
Poplar in Sweden produces biomass faster than the domestic trees. In the southern parts of Sweden plantations has been made with good results. In the northern parts survival is a problem that needs to be solved before plantations can be made for commercial use.
En skogshistorisk jämförelse mellan två närbelägna landskap med olika mångfald i östra Småland :
This study shows the historical development of the forests in Hornsö and Ebbegärde state forest area in eastern Småland situated in southern Sweden..
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.
Samverkan på svenska mötesdestinationer.
Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization.
The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.
Jämförande studie av normal ERG-svar hos tre olika hundraser :
The purpose of this study was to compare normal electroretinographies (ERGs) from three different canine breeds in order to evaluate if there were any marked similarities or differences between these breeds as to ERG responses. It is known that healthy dogs from different breeds but also dogs within the same breed but in different age categories may have different appearances of their ERG responses. This may be a problem when evaluating if an ERG is normal or not from a dog within a breed not previously examined. Because of this it is important to obtain normal values for each breed and age group in order to be able to use these for later comparisons of ERGs obtained from individuals affected with various retinal diseases.
In this study we have chosen to examine dogs within the three breeds: Labrador Retriever (LR), English Springer Spaniel (ESS) and Chinese Crested Dog (CCD). All of these breeds may be affected with hereditary retinal diseases such as Progressive Retinal Atrophy (PRA).
It is possible that ERG-responses vary due to a number of different factors.
Södras gröna skogsbruksplaner ur ett landskapsperspektiv :
The aim of the "Green forest management plans" is to help forest owners to reach the
environmental goal of the forestry act. But are they able to do that? Is it possible to plan preservation of species on single estates? How do single-estate-plans differ from a landscape analysis and how can the landscape approach be used in operative planning? This work was initiated to give an answer to these questions.
This study was made in a landscape of 4200 ha in Östergötland county, south-eastern Sweden. A lanscape analysis was made and then compared to the Green forest management plans in the same area. The nature conservation areas (areas that were set aside to be managed with environmenatl goals) differed quite a lot between the two alternatives.
Skottbetning på granplantor i Kolmården : omfattning och påverkande faktorer
In the Kolmården area, northeast of Norrköping in south-central Sweden, it was discovered that shoots of spruce Picea abies, plants to a seemingly large extent had been browsed by deer. The area inhabits a dense red deer population, alongside with moose and roe deer, and red deer is thus suspected to cause the damage. The main purposes of this study are, however, to estimate the extent of the shoot-damage and to investigate what factors that may affect the browsing of shoots.
For each stand information was recorded about the age of the plants, area for the stand, height over the sea for the stand, site productivity, type of plants and stand-history.
The study was done in three areas: Simonstorp, Stavsjö and Valinge. At Simonstorp and Stavsjö, respectively, 10 stands were chosen for study and on Valinge six stands. In each stand, 10 plots were sampled.
Motivation i praktiken - En fallstudie om vad som skapar ho g motivation hos erfarna IT-konsulter
The purpose of this study is to examine what creates motivation in the workplace of a small company with a high employee satisfaction index. The case study consists of qualitative interviews that help explain what the most important motivational factors are for the experienced IT consultants in a company that was founded by a circle of friends. The study concludes that the unique and equal pay model implicates an economic risk to the individual consultant but results in liberties, synergies and benefits. These appeal more than either self-employment or work at a larger IT consultancy that several consultants have backgrounds in. An expansion is ongoing since two years back, which threatened the culture but implicated opportunities for the individual consultants.
Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides
Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides.
This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very
rare and decreasing, and Norrbotten where this study was conducted.
Några vanliga ogräs : en litteraturstudie av arternas biologi samt förebyggande och direkta kontrollåtgärder
The Swedish Board of Agriculture initiated this undergraduate thesis. There is a database on their homepage that includes chemical treatments for different weed species. There is also space for preventive and mechanical control methods. This is an undergraduate thesis that reviews these control methods for the most important weeds in Sweden.
The species reviewed are:
Creeping perennials:
Common Couch Elytrigia repens (L.) Desv. ex Nevski
Creeping Thistle Cirsium arvense (L.) Scop.
Perennial Sow-thistle Sonchus arvensis L.
Field Horsetail Equisetum arvense L.
Colt's-foot Tussilago farfara L.
Stationary perennials:
Dock Rumex L.
Mugwort Artemisia vulgaris L.
Dandelion Taraxacum F.
Smittskyddsrutiner vid flytt av djur mellan djurparker
Animals in zoos live in small enclosed areas. If a pathogen is introduced to the zoo, the animals are extremely vulnerable. The highest risk of introducing new pathogens occurs when new animals are introduced to the collection. Therefore it is essential that zoos have a protocol in place for disease prevention.
This review has studied literature on the subject of disease prevention protocols when translocating animals between zoos.
Individuell tillväxt och substratval hos en lokalt differentierad population av Asellus aquaticus
Local differentiation may occur during a short period of time and is part of the formation of new species. The isopod Asellus aquaticus is an example of a species in which local adaptation has occurred during a short period of time. An establishment of stonewort (Chara spp.) vegetation in Lake Tåkern (in the 2000) resulted in two different Asellus ecotypes; a lighter pigmented, smaller one that lives among stoneworts grazing periphytic algae, and a darker, larger ecotype that feeds on decaying leaves in reed (Phragmites australis vegetation. The purpose of this study was to examine whether there are differences in growth between ecotypes, depending on whether the food was periphytic algae or leaves, and to study the choice of substrates between the two food types. For the study, animals from both habitats were brought in from Lake Tåkern to the laboratory.
Utilization of different habitatsin Colobus angolensis palliatus in the forests of Diani Beach, Kenya
The Angolan black and white colobus monkey (Colobus angolensis palliatus) is an arboreal primate that inhabits coastal forest fragments on the south cost of Kenya and is consequently vulnerable to forest fragmentations. The study was carried out in March and April 2011 in Diani Beach in Kenya where two of the largest populations of the species are distributed. This study is a pilot study to test methods for a Master?s thesis. The aim was to investigate any variations in use of two habitats of C.a.
Tetratermmodellering och regressionsanalyser mellan topografi, tetraterm och tillväxt hos sitkagran och lärk : en studie i norra Island
This study was made in an attempt to give the forest research centre Mógilsá a producedtetratherm map and a better understanding of how topography and temperature influencethe growth of two tree species. The digital tetratherm map model, covering the northernpart of Iceland, was developed to investigate the correlation between tetratherm and thegrowth of Picea sitchensis and Larix (sukaczewii + sibirica). The study confirms theusefulness of digital terrain models in providing data for a lot of different factors and forthe tetratherm model. Hopefully will this tetratherm map be used in future studies.Secondly, investigations were made correlating the growth of the two species againsttopographic factors representing height above sea level, distance to the sea, slope andtopex. Thirdly, investigations were made comparing the aspect and the ground shape tothe growth.The growth rate of Larix had strong significant correlations to the tetratherm and thedistance to the sea- factors.