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599 Uppsatser om Manually killed trees - Sida 40 av 40

Förutsättningar för återintroduktion av stora gräsätare i Sverige

Biodiversity is under threat in Sweden and many species are on the brink of extinction. This is mainly due to the large-scale drainage projects during the 19th and 20th century and the increasingly intensive land use in agriculture and forestry. The intensive land use with sharply defined boundaries between the production units has in many cases led to either overgrazing or overgrowing. As a result many species have been pushed back to "leftover" habitats like shooting ranges, power line corridors, roadsides, dumps, embankments and other similar areas. Therefore the question has been raised, wether or not it is needed to re-introduce large herbivores into the wild in order to maintain the biodiversity that is related to the extensive land use.This study has been conducted as a literature review and will focus on the European bison?s (Bison bonasus) impact on other species and biodiversity; conditions for reintroducing large herbivores in Sweden are also discussed.Free roaming populations of large herbivores have a positive impact on plants, insects and many other groups of organisms.

Lövskogsmålen i FSC-certifierat skogsbruk : tolkning, uppföljning och skötseldirektiv

Den mest eftertraktade råvaran i svenska skogar är barrvirke och detta har sedan länge varit vägledande för skogsbrukets planering och skötsel. Brandskydd, ökat betestryck och skötsel för barrträd har missgynnat lövträden. Eftersom lövskogar i den boreala zonen tillhör ett av de artrikaste ekosystem är kontinuerlig förekomst av lövträd och lövdominerade bestånd viktigt för den biologiska mångfalden. Den standard skogsägare certifierade enligt FSC (Forest Stewardship Council) har att följa innehåller två lövindikatorer, 6.3.8. och 6.3.9..

Vad påverkar skogsägarnas naturhänsyn vid föryngringsavverkning i region Mellannorrland? :

The objective of this thesis was to investigate what influence nature conservation measures taken at regeneration felling. Factors analysed were the forest owners´ situation and their characters, and information activities from wood-suppliers and the Regional Forest Board (RFB). The inventory was performed with a posted questionnaire followed up by telephone to forest owners and a posted questionnaire to wood-buyers. The forest owners were grouped in three strata, depending on the quality results (D- polytax inventory) of the taken forest conservation measures, and for this investigation forest owners were sampled from the population in the tree groups. In total 73 % (41/56) of the sampled forest owners answered the questionnaire Group A (17 answers): Good judgement Group B (19 answers): Bad judgement Group C (5 answers): This group was formed from the forest owners that were informed, by RFB, about nature conservation measures and culture history consideration before the regeneration cutting.

Effekter av gödsling i äldre tallbestånd på renbetesväxter i fält- och bottenskikt :

Reindeer husbandry and Forestry are both area related industries and will in big extent use the same lands. Conflicts often arise because of that the industries have different interests. Many of the activities done by the forestry influences the reindeer husbandry in an undesirable way, simultaneously as the reindeer husbandry activities can have negative consequences for the forestry. One such forestry activity is fertilization. It was during the 1960´s forest fertilization began to be practiced and the reason was that the increase in growth that the fertilization gave could be able to cover for the future shortage in wood many feared. During the 1970´s when the fertilizing activities were most intensive about 200 000 ha was fertilized annually.

"Den kemiska bekämpningen av skadlig lövskog har öppnat helt nya vyer för skogsbruket" : flygbesprutning med herbicider i Arjeplog 1953-1978

Attityden gentemot lövträd och lövskog i norra Sverige började förändras i mitten av 1900-talet. Tidigare var lövträden en resurs inom det agrara samhället, men genom det industriella skogsbrukets utveckling började man alltmer betrakta lövträden som ett problem. Lövträden gav sämre lönsamhet på grund av att de inte efterfrågades inom industrin och lövträden ansågs även hota barrträden och deras föryngring genom sin förmåga att föröka sig vegetativt genom stubbskott och rotskott. Det fick till följd att det inom skogsbruket talades om ett ?lövproblem?.

Undersökning av självspridning av contortatallen i norra Sverige

Over the past 40 years 600 000 ha of lodgepole pine (Pinus contorta ssp. latifolia (Engelm.) Critchf.) has been planted in Sweden (280 000 ha on SCA's forest land alone which represents about 15% of the company's total forest land area). In the early 70's SCA situated a number of experimental stands in order to investigate different aspects of the exotic tree, primarily growth rate. To be able to compare the two species plots with scots pine (Pinus sylvestris L.), this species was also planted at the same time and under the same conditions. A number of questions should always be raised when exotic species are introduced in an ecosystem. Invasiveness, the pathogen situation and purely ethical issues should be discussed.

Kan risken för spontan contortaföryngring elimineras genom hyggesbränning? :

Sweden has almost 600 000 hectares planted with lodgepole pine, and large areas are soon ready to be clear-felled. The provenances that have been planted are producing high level of permanently closed, so called serotinous, cones. In their natural setting, the Canadian boreal forest, these cones are opened mainly after crown fires when the heat make the resin between the cone scales melt, which releases the seeds. This is viewed as an adaption to the fire regimes that prevail over the natural distribution area of lodgepole pine. Because of the short flame-exposure that occurs in a crown fire, the seeds can survive.

Den goda platsen : om varför vi tycker mer om vissa platser än andra

How can man´s place preferences be explained? What aspects influence our experience of place? This essay attempts to define a good place to be drawing from sources of environmental psychology as well as other landscape theories and relating these findings to the landscape architect?s field of work. Physical place properties, like physical elements and their juxtaposition in space are examined in relation to place preferences as well as psychological properties, such as place attachment and place identity due to cultural or social aspects.There are strong cross-cultural similarities in our place preferences but there are also some differences. Natural elements, like trees or water, are widely preferred over man-made ones, like buildings, roads or fences.Man seems to be sensitive for the balance between different place characteristics, like the balance between ?soft?, natural, elements and ?hard? man-made ones or the complexity versus the legibility of place.

Uppföljning av plantering på nedlagd åkermark i Skåne 1991-1996 :

The study was performed for the Swedish Regional Forestry Board in Södra Götaland. The study examines broadleaf plantations on former farmland that were planted between 1991 and 1996 with subsidy payments for conversion of farmland into forest. In particular, the study reviews forests planted in 1991-92 and 1994-96. In the early 1990s, Swedish agriculture was deregulated and direct subsides to farmers ended. The Swedish state instead granted farmers financial support and offered incentives for conversion of farmland and investments in order to make their unproductive land productive. The state supported conversion of farmland to broadleaf forest, forest for energy biomass production, or establishment of wetlands on former farmland. The County Administrative Boards and Regional Forestry Boards together monitored the planting of broadleaf forests.

Design, anläggningsmetoder och skötseltekniker för hagmarksbestånd :

SUMMARY Establish a pasture There is many valuable nature and culture landscapes in Sweden that has developed during a long period of time, throw natural processes or human use. Unfortunately lot of these are disappearing. My thought with this work is to explore the possibility to establish new areas with similar qualities. The motive for this is that attractive countryside biotopes are well worth to use as model to enrich the urban landscape. Another thought has concerned the people that establish, build and manage landscapes and parks. They often have varied views, both coming from a difference in background and previous experiences.

Den skogliga informationens roll i ett kundanpassat virkesflöde : en bakgrundsstudie samt simulering av inventeringsmetoders inverkan på noggrannhet i leveransprognoser till sågverk

This MSc thesis is divided into two parts. The first part deals with the need for information from forest campartments selected for clear cutting, in connection with planning in an integrated forest- and sawmill enterprise. A review of literature is followed by a case stud y, where present conditions in a Swedish forest company are compared with current research in the area. The seeond part consists of a simulation stud y, which aims at camparing the accuracy of inventory estimates using different methods. The estimates are delivery forecasts, covering one month consumptian of timber in a large sawmill.

Inverkan av årstid för förstagallring på avverkningsskador i contorta och tall :

SCA har idag cirka 280 000 hektar beskogad med contortatall (Pinus contorta Dougl. ex Loud. var. latifolia Engelm). Stora delar av den arealen har kommit in i, eller är på väg in i, gallringsbar ålder.

English Arts and Crafts gardens and how they can be modernised in Sweden

The aim with this thesis was to investigate what characterises an English Arts and Crafts garden how they could be modernised in Sweden. My research was limited to 20 weeks of full-time writing and worth 30 ECTS. Through literature studies, interviews and site visits I could analyse my findings which resulted in a concrete garden design project. The Arts and Crafts was a movement that started in England during the 1880?s and evolved as a reaction towards the industrialisation. The influence came from the writings and practices of John Ruskin (1819-1900) and William Morris (1834-1896) who advocated the importance of craftsmanship. The Arts and Crafts movement also became a ?recipe for life? and was associated with a healthy and morally pure way of living.

Inflytande av sommarväder på kornas val att vara på bete eller inne dagtid i en besättning, samt studier av andningsfrekvens och yttemperatur hos fokaldjur :

SAMMANFATTNING När man i tidigare undersökningar studerat betesgång för mjölkkor har klimatet på betet inte beaktats. En höglakterande ko producerar mycket värme som hon måste avge till sin omgivning för att kunna bibehålla sin kroppstemperatur. De sätt som djuret kan avge värme på är begränsade och påverkas av flera klimatfaktorer samt djurets genetiska och biologiska förutsättningar. Antalet dagar som registreringar gjordes under denna studie blev av flera olika anledningar få, 18 dagar. Klimatet utomhus under studien registrerat som globtemperatur varierade från 22,4 till 34,7ºC. Då djurskyddslagen skall främja djurens hälsa och djurets naturliga beteende fick en grupp 126 höglakterande kor möjlighet att välja uppehållsplats under tiden 26 juli till 11 augusti. 2004. Korna fördes ut på betet vid niotiden på förmiddagen och var därefter fria att gå in och ur stallet efter egen vilja tills de togs in för kvällsmjölkning omkring klockan tre påeftermiddagen.

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