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544 Uppsatser om Tree mortality - Sida 36 av 37
Satsa på leken! : en studie om skolgårdens betydelse för barns lek och utveckling
The intention of this final thesis is to examine how to create a schoolyard that inspires children at the age of 6 ? 12 years to play and give them possibility to develop. To get a lot of knowledge in this subject, I have combined studies of literature with practical studies at Hosjöskolan in Falun. During my practical studies I have done interviews, walks in the area with the children and visited other schoolyards. I have based a design proposal for the schoolyard of Hosjöskolan on these studies.
Uttag av energisortiment vid gallring av contorta, ett komplement till konventionell gallring? :
A recommendation for stand treatment of lodgepole pine (Pinus contorta) is, in a scientific point of view, lacking when it comes to harvesting for biomass energy. Within the next decades it is expected that 280 000 hectares of lodgepole pine will have reached thinning age on the domains of Svenska Cellulosa Aktiebolaget (SCA). Due to this the interest has grown rapidly for studying the possibilities of harvesting biofuel assortments already in the first thinning.
In this study the distribution of the biomass within lodgepole pine trees has been studied and taken into account for estimating the proportions of harvested assortments when using different methods of thinning. The methods studied were conventional biofuel-harvesting (with delimbed branches gathered separately from the round wood) and thinning with cutting of round wood and long tops (incl.
Metoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket, efter den senaste skogsvårdslagenMetoder för att undersöka effekterna av naturvårdshänsynen i skogsbruket, efter den senaste skogsvårdslagen.
In 1994 a new Forestry Act was accepted in Sweden. One of the aims of the law is to raise consideration forpreservation of biodiversity. Since the new law got accepted and some time has passed, there now lie someinterest in examining whether the law has been effective towards its purpose. Methods suitable for analysishave been examined during this study. The content of this pilot study is based around five parameters whichcan be used to validate the effects of the new law.
Nyckelbiotoper - urskogsrester eller kulturprodukter? : beståndshistorik i tolv nyckelbiotoper i Lycksele kommun
Since 1993 the Swedish Forestry Administration conducts a nation-wide inventory of wood-land key habitats covering all forest land in Sweden. The inventory aims at mapping and describing habitats where redlisted species occur or can be expected to occur. According to the inventory stand history is crucial to the presence of red-listed species. However, the current knowledge of stand history in woodland key habitats is very limited.
The purpose of this work is to describe stand history in woodland key habitats, i.e. fire history, human activities - mainly cuttings - and structural changes.
A value chain analysis for timber in four East African countries : an exploratory case study
This study is a value chain analysis for timber in East Africa. It was commissioned by Vi Agroforestry, a nongovernmental organisation registered in Kenya, Rwanda, Uganda and Tanzania engaged in a rural development program that involves promoting tree planting and enterprise development (Vi Agroforestry, 2012). The purpose of the study was to identify and describe common value chains for timber in the countries where Vi Agroforestry operated.
Value chain is a concept and a framework describing how to structure information regarding activities included in satisfying a certain customer need, e.g. procurement, logistics, transactions, production and marketing.
Naturligt föryngrade huvudstammar i röjda bestånd etablerade efter plantering på SCAs mark
Dagens dominerande föryngringsmetod i Sverige är plantering som utgör 75 procent, därefter kommer naturlig föryngring som utgör 18 procent. Anledningen till att plantering är den dominerande föryngringsmetoden är att ofta används förädlat material vid tillverkning av plantor vilket ökar tillväxten och överlevnaden samt minskar omloppstiden. Föryngringsperioden är kortare hos plantering jämfört med naturlig föryngring. Röjning är en beståndsvårdande utglesning som ska gynna stammar med bra egenskaper. Faktorer som kan påverkas med röjning är trädslagsblandning, tillväxt och kvalitet.
Skötsel av vägnära skog för trafiksäkerhet och naturupplevelse :
A great deal of the nature experience we get today is from travelling along our roads, which to a large extent go through the forest landscape. This makes the forest along our roads interesting to look at from a nature experience perspective. The main idea of this work is to increase the awareness of how we are affected by the forest when we travel through it and find out how the forest should be adapted to the road environment to create a pleasant nature experience as well as increase traffic safety.
0.9 % of Sweden's total forest area (equivalent to 200 000 hectares) is in close proximity to roads. Additionally, in Sweden 440 million hours are spent behind the wheel of which a great deal probably is spent on roads surrounded by forest in some form.
Alternativa skogsbruksmetoder i Norden : ett välbehövligt komplement?
Clearcutting systems have been the dominating silvicultural approach during the last decades in the Nordic countries. While economically rational, it is also leading to a trivialisation of the flora and fauna, and may result in negative reactions of people in urban settings. As a consequence of this, and a more diversified view on which goods and services forests should deliver, there is an increasing interest in broadening the range of silvicultural methods that are used.
The term continuous cover forestry (CCF) represents a suite of methods that have gained increasing interest in the Nordic countries. In CCF a considerable amount of the trees are left after harvest to favour values that require a continuity of tree-covered areas. There are thus hopes that this method will meet the needs for maintaining biodiversity and satisfy social and cultural values.
Produktion och beståndsstruktur i fullskiktad skog skött med blädningsbruk
Denna studie behandlar tillväxt och beståndsstruktur samt sambandet mellan dessa i skog skött med blädningsbruk. Blädningsbruk förutsätter fullskiktad skog med fallande diameterfördelning, under nordiska förhållanden vanligtvis dominerad av gran (Picea abies (L.) Karst). Strukturen i fullskiktad skog är resultatet av tillväxt, skörd/mortalitet och inväxning. Kunskap om det komplexa samspelet mellan dessa faktorer ger skogsskötaren möjlighet att planera och sköta fullskiktad skog för en hög och uthållig produktion.
Undersökningar och litteratur inom aktuella områden tas upp i en litteraturstudie. Ämnen som behandlas är: definitioner och begrepp, diameterfördelningen i fullskiktad skog och hur denna kan beskrivas, blädning och andra avverkningsstrategier samt tillväxt- och produktionsundersökningar i Norden, Europa och USA.
Rosenlunds bankar : Erosion och förändring sedan 1960
During the 1960´s and 1970´s the number of grey seals in the Baltic Sea was decreasing rapidly, mostly due to hunting and toxic substances like DDT and PCB. When hunting became less intense and toxic substances decreased in the environment the grey seal population started to increase. Today grey seals are found common in the Baltic Sea and have started to become a big treat and a problem to the fishing industry. The grey seal destroys and enters fishing traps and consumes large quantities of the fish that have been caught.The knowledge of the grey seal, like abundance and food preferences, is today limited. It is also important to define the position of the grey seal in the ecosystem in the Baltic Sea and to be able to predict changes that could occur if the population would rapidly decrease or increase.
Födosammansättning hos gråsäl (Halichoerus grypus) samt test av flotte för insamling av sälfekalier.
During the 1960´s and 1970´s the number of grey seals in the Baltic Sea was decreasing rapidly, mostly due to hunting and toxic substances like DDT and PCB. When hunting became less intense and toxic substances decreased in the environment the grey seal population started to increase. Today grey seals are found common in the Baltic Sea and have started to become a big treat and a problem to the fishing industry. The grey seal destroys and enters fishing traps and consumes large quantities of the fish that have been caught.The knowledge of the grey seal, like abundance and food preferences, is today limited. It is also important to define the position of the grey seal in the ecosystem in the Baltic Sea and to be able to predict changes that could occur if the population would rapidly decrease or increase.
Välkommen : vackrare infart till Vilhelmina
The purpose of this thesis is to show how a good approach can be designed, focusing on the southern approach to the Swedish town Vilhelmina. Prior to the car being part of everyday life, the approach was a road where the town showed itself from the very best side. When the amount of traffic increased, so did noise and other disturbances, and as a consequence industrial areas replaced the residential buildnings at the approaches. Today, the pendulum is turning back and in recent years the approach is regarded as a place to introduce the town. The approach is also the place where cars should slow down from the speed of the main road to the speed of the city.
Rum, form och växter : en sammanställning av växtkompositionsprinciper och tillämpningar
Sammanfattning
Rum, form och växter är ett avslutande examensarbete som handlar om växtkomposition. Jag har valt ett antal profiler inom områdets principer om rumsskapande, komposition, färglära och några tillämpningar som jag studerat på plats samt gjort egna förslag.
I detta arbete har jag börjat med rummens uppbyggnad, deras förutsättningar och sammanhang och hur detta påverkar platsen. Formen och proportioner skapar olika upplevelser och inhägnaden som har betydelse för intrycket. Människor får olika känslor beroende på rummets öppenhet, slutenhet och skala.
Kapitlet som handlar om gångar berör uppbyggnaden och människans rörelsemönster i dessa.
Föryngringsresultat och beräknad virkesproduktion i naturligt föryngrade tallbestånd i Västerbotten under mitten av 1990-talet :
According to the Board of Forestry, in Västerbotten, many natural regenerations of Scots pine (Pinus sylvestris) carried out on privately owned forest in the middle of 1990 in Västerbotten have rendered a bad regeneration outcome and will provide a low future forest production. The Board of Forestry believes that the negative result can be explained by the fact that the regeneration has been carried out in wrong locations and that scarification failed to work as planned. In order for an accepted rate of regeneration the guidelines of the Forrest Act require, not less than 10 years after final cutting at natural regeneration, that there should be at least 1300 (site indices 16 m) - 1700 (site indices 20 m) main crop stems per hectare. Main crop stems are defined as stems according to the place of growth and appropriate tree type, in addition with regard to quality, stage of development and damage risk have a prospect of succeeding. In addition main crop stems should be separated by surface so that the proportion sample plots with 3 meters radius, and lack main crop stems, are not more than 10 % of site indices 14 meters or higher.
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.