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377 Uppsatser om Vegetation i vägmiljöer - Sida 6 av 26
Användning av geografiskt informationssystem (GIS) vid studier av nötkreatur i landskapet - en pilotstudie :
The Animal Protection Agency was in 2006, commissioned by the Government to: Evaluate how free range animals in the winter, can be kept and managed with special emphasis to animal welfare. The Animal Protection Agency was closed later in 2006 and the commission moved to the Swedish Board of Agriculture. The keeping of free range out wintered cattle, certain basic requirement are needed: by regulation, cattle should have access to a lying hall or other building that gives protection against aversive weather and wind and should offer a dry and clean lying area. There is a possibility for farmers that get an exemption from this regulation. But cases regarding farms which have had difficulties for this exemption has led to a discussion about if the animals can get the same protection in the nature which is comparable to a lying- hall.
Kan markfuktighetskartor användas för att hitta skogsmark med hög bonitet? : ett gis-baserat försök med dtw-index och laserskannad övre höjd
The depth-to-water-index (DTW-index) is derived from digital elevation models (DEM) to map soil wetness, in terms of distance from soil surface to the ground water table. The aim of this GIS based study was to investigate the existence of a relationship between DTW-index and forest site productivity (SP). The belief of such an assumed relationship was based on knowledge that the ground water level is related to site properties that can either promote or impede tree growth.
Data primarily comprised rasters of the Krycklan catchment in northern Sweden and depicted DTW-index and a laser scanned vegetation height. The 100th height percentile of each pixel in the vegetation raster was assumed to mirror the top-height, letting it act as a relative measure of SP within a delineated area of equal stand age.
Vildkaniner som naturvårdare? : En studie om hur kaniner påverkar pH, mängden öppen sand och vegetation på en sandstäpp i sydöstra Skåne.
Sandstäpp, eller ?xeric sand calcareous grasslands?, är en starkt hotad naturtyp i Sverige. Sandstäpp hyser många unika och sällsynta växter som kräver bland annat högt pH-värde och uppbrutet vegetationstäcke. De största hoten mot sandstäppen är försurning och igenväxning. I denna studie undersöktes om vildkaniner (Oryctolagus cuniculus) kan motverka dessa hot genom att gräva upp kalkrik sand och därmed gynna sandstäppens unika vegetation.
Tick burden in neonatal roe deer (Capreolus capreolus): the role of age, weight, hind foot length, and vegetation and habitat on bed sites
This thesis deal with tick burden on roe deer (Capreolus capreolus) fawns, in relation to age, weight, hind foot length, and as well as to vegetation and habitat on bed sites. Roe deer fawns (N = 25) were captured from May 27 to June 27. Samples of ticks were collected and tick burden were estimated. Of all sampled ticks the nymphs and adults were Ixodes ricinus, while the larvae were not identified. 4.4 % of the sampled ticks were larvae, 55.0 % nymphs, 26.8 % adult females, and 13.8 % adult males.
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.
Plantering av gran (Picea abies) på kalhyggen och självföryngring under högskärmar av björk (Betula pendula och Betula pubescens) : föryngringsresultat 7-10 år efter avverkning
The aims of the silvicultural method natural regeneration of spruce (Picea abies L. Karst) in birch (Betula pendula and pubescens) shelterwoods are to establish a new stand of tree seedl-ings and to protect those from high groundwater levels, frost damages and grass competition during its first life years.
The aim of this work has been to (i) describe how shelterwood and stand characteristics influ-ence the results from using natural regeneration of spruce protected by a shelterwood of birch, and to (ii) compare those regeneration results with planting of spruce after soil scarification in clear-cut areas.
Totally 17 harvesting sites have been inventoried and 15 of those included natural regenera-tion in birch shelterwoods, and two were subjects to soil scarification and planting of spruce. The sites represented 7-10 year old final cuts and are located in the coastal (eastern) region of the province of Norrbotten in Sweden. In all areas shelterwood and stand characteristics, as well as the number of main crop seedlings and the height of the highest main crop spruce seedling, were estimated and registered in all areas.
Vegetation för öppna dagvattenanläggningar : användningsområden och utformning i en stad
Dagvattnet i stadsmiljö har länge varit något som ska ledas under marken i rör. När vattnet rinner på gator, genom industriområden och villakvarter samlar det på sig en mängd förore-ningar från dessa ytor. När sedan vattnet rinner ner i kulverterade rör finns det ingen chans för dagvattnet att renas innan det når ut till sjöar och hav. Genom att istället anlägga öppna dag-vattensystem i form av dammar eller våtmarker med mycket vegetation ökar reningseffekten av vattnet. Sådana anläggningar utgör också en varierad karaktär i staden.
Prefab kontra naturlek : förvaltarens perspektiv på anläggning och skötsel
Hur själva leken och barns utveckling påverkas av naturen och värdet av naturlekplatser har tidigare haft låg prioritet inom forskningen men är idag ett mycket diskuterat ämne. Genom att gamla planeringsnormer om avstånd, innehåll och storlek på lekplatserna har tagits bort finns en risk för att barns möjligheter till att leka utomhus minskar. Vikten av en säker lekplats har kommit att ta allt mer fokus. För att studera de förändrade förutsättningarna för barns utomhuslek riktar sig därför detta arbete mot de skillnader i anläggning och skötsel som förvaltare upplever mellan naturlekplatsen och den prefabricerade lekplatsen. Inledningsvis gjordes en litteraturstudie över vad forskning och litteratur visar gällande barns lek.
Sportfiskares slitage på Mörrumsåns stränder och konsekvenser för Tjockskalig målarmussla : - kan spänger skydda från erosion
Mörrumsån har de förutsättningar som krävs för att Tjockskalig målarmussla (Unio crassus) skall kunna leva och föröka sig, men detta sker inte i samma utsträckning som tidigare. Ett samband mellan vattnets riktning söderut mot utloppet till Östersjön och minskad föryngring av Tjockskalig målarmusslas inventerade bestånd i Mörrumsån finns. Föryngringen uteblir samtidigt som man hittat fler döda musslor ju närmre åmynningen man kommer. Orsakerna till detta kan vara flera då denna mussla är beroende av specifika förhållanden under flera faser i sin utveckling och fortplantning. Ett av hoten är grumling av bottnar.
Förekomst av törskate (Cronartium flaccidum, Peridermium pini) på tall (Pinus sylvestris) i relation till markfuktighet och fältskikt : en studie om 2000-talets törskateepidemi i norra Sverige
Resin-top disease is a rust fungi that occurs both as a host alternating form, Cronartium flaccidum G. Winter., and as a non-host alternating form, Peridermium pini Pers. The host alternating form can use a variety of hosts but the most commonly used species in the boreal forest is Melampyrum sylvaticum. In Scandinavia the Resin-top disease infect Scots pine, Pinus sylvestris L. The fungus infects the needles through the stomata and then grows through the branch to the stem where it strangulates the vessels transporting water and nutrition to the treetop, which kills the top.
The shift in forest and tree limits in Troms County - with a main focus on temperature and herbivores
To better understand how various factors affect the establishment of forest and trees around the tree line-ecotone, this study was conducted in Troms County, Norway. The altitude of different forest and tree limits together with the surrounding vegetation type were collected during August 2011. Comparisons of the collected data were made with previously collected data from the same sites conducted 1914 and 1915. On average the forest limit has expanded with 26 meters in altitude, however, an expansion is not statistically significant for the whole area. The tree limit has significantly expanded in altitude.
Viltets inverkan på vegetationsutvecklingen i en Sydsvensk skogsföryngring :
Herbivore impact on the Swedish forest has under a long time been a common subject of
debate. There are many different opinions depending on what direction the forest owner has with his/her forest. Populations of moose and roe deer have increased significantly in Sweden during the last decades. The purpose of this study is to get a full picture of the herbivore impact on the regeneration areas. The field work was done once a year for seven years (1999?2005).
Öjingsvallen vid sjön Öjingen : en pollenanalytisk studie av en fäbodvall i Ängersjö, Hälsingland
By using pollen analysis and 14C-dating, the history of vegetation and land use at the old shieling place (Sw: fäbodställe) Öjingsvallen in Ängersjö parish, central Sweden, was studied. The aim of the study was to answer the following questions:
1) When was Öjingsvallen established as a shieling place?
2) What was the land use at Öjingsvallen?
3) Was the use of Öjingsvallen as a shieling place affected by the agricultural crisis in the 14th and 15th centuries?
4) Is there any relation between the establishment and land use of Öjingsvallen as a shieling place and the historically known increase in the number of shieling sites known to have taken place in the 16th and 17th centuries?
5) Was the use of Öjingsvallen as a shieling place affected by the iron production in the area?
According to the study, Öjingsvallen was probably established as a shieling place during the period A.D. 300-700. The main land use at this time was forest grazing.
Where has the fertilizer gone? Closing the nutrient budget for a eucalyptus fertilization experiment in southern China
An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.
Importance of mire plant community composition when estimating ecosystem level methane emission
Metan är en stark växthusgas som är viktig att ta med i beräkningarna när det gäller klimatförändringar. Feedback från myrmarker vid en ökad temperatur i samband med klimatförändringar har diskuterats, bland annat eftersom myrmarker är en källa för metan till atmosfären. Det finns många faktorer som påverkar metanemission, och en av dom är vegetation. Olika sorts vegetation tros bidra olika mycket till avgivningen av metan. Syftet med denna studie var att undersöka hur stor betydelse det har att ta med olika växtsamhällens sammansättning i beräkningarna för att uppnå korrekta uppskattningar av metanemission från myrmark på ekosystemnivå.