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891 Uppsatser om Boreal forest - Sida 11 av 60

Motiv och värdering vid köp av skogs- och lantbruksfastigheter i Kronoberg och Blekinge

The purpose of this study is to find out how buyers of forest-and farm land have valued the property's various parts. How buyers has valued the forest, field, pasture, house and the farm buildings on their property. A questionnaire with 22 questions was sent to 68 people how had bought a property in Kronoberg or Blekinge. They had bought the property in 2010 and first half of 2011, and the properties have been provided by LRF-konsult. To each question there were several alternatives and the buyers would choose the alternative that was most similar to his or her opinion. The study is based on 57 responses.

Vad styr förekomsten av sälg och asp? : en studie av olika beståndstyper inom Hamra kronopark, Dalarna

Aspen (Populus tremula L.) and goat willow (Salix caprea L.) are two important tree species in the aspect of nature conservation. Due to the elimination of forest fires, a former negative attitude towards deciduous trees in forestry and a strong herbivore pressure, these tree species have been negatively affected during the last fifty years. The aim of this study was to investigate whether the occurrence of aspen and goat willow could be related to either human impact or to site properties, such as ground moisture and vegetation type. A side study included an inventory of a number of cyanobacterial tree lichens on aspen and goat willow in order to try to relate the occurrence of these lichens species to stand history and stand properties. The study was performed in Hamra State Forest in northern Dalarna. Nature reserves were compared with stands in managed areas.

Effekten av kvävegödsling på gasproduktionen vintertid i boreala sjöar

To investigate effects of nitrogen on in-lake CO2 and CH4 production during winter, three pair of lakes was subject for a fertilizing experiment in which one lake in each pair was fertilized with nitric acid (HNO3) directly into the water column in the summer of 2012. The lakes in each pair are assumed to be morphologically, hydrologically and biologically similar, that is, the non-fertilized lakes are considered references. The pairs do differ in one major way by being progressively less humic, going from around 25 mg/l to 10 mg/l DOC. Sampling and analysis was carried out at the end of the frozen period in 2013. Results show a significantly higher concentration of both CO2 (p<0,001) and CH4 (?=0,1, p=0,053) between impact and reference sites in the two less humic pairs.

Hur kopplad är asp till tidigare jordbruksmark? : en studie av aspförekomst och tidigare markanvändning i fem län i Mellansverige

Aspen (Populus tremula) is a tree that is important for biodiversity. It is a pioneer tree that is favored by much light. It is possible that aspens that regenerated on agricultural land have a different importance for biodiversity than aspens that regenerated in forests, since their conditions have been different. By studying how the land use have changed you can see how many of today?s aspens regeneretad on agricultural land.

Träddelsuttag eller massavedsuttag i förstagallring?

The purpose of this study is to compare the economic differences between withdraw of forest fuel and withdraw of pulpwood in first thinning, to see which method gives the maximum profitability (income - cost). Another purpose is to investigate the economic impact of the thicket cleaning. The study compares four different methods: i) pulpwood output with thicket cleaning, ii) pulpwood output without thicket cleaning, iii) forest fuel output with thicket cleaning and iv) forest fuel output without thicket cleaning. The study was conducted in a 30-years old stand, dominated by spruce, outside Harg in Uppland. The method that generated the best economic net income was pulpwood without thicket cleaning. It generated a positive net of 1,383 SEK per hectare. Forest fuel output without thicket cleaning also generated a positive net in 720 kronor per hectare.

Modellering av oorganiskt kol i boreal jord och vattendrag med hjälp av PHREEQC : Modelling of dissolved inorganic carbon in boreal soils and streams using PHREEQC

Syftet med examensarbetet har varit att studera kol i mindre vattendrag med hjälp av jämviktsmodellering i PHREEQC. Fokus har varit dynamik av löst icke organiskt kol (DIC) samt att förstå hur mycket koldioxid (CO2) som avges från mindre vattendrag och om den mängden har signifikant inverkan på den globala kolbalansen. Med hjälp av provtagen data från Krycklans avrinningsområde år 2003-2007 och 2009 har modellering av DIC och pCO2 utförts med målet att se förändring både över säsong och nedströms i ytvattensystemet. För att utvärdera modellen har tillhandahållen data över uppmätt pCO2 använts. Målet var att jämföra modellerade och tillhandahållna pCO2-värden för att se hur väl modellen kunde beskriva verkligheten och om den fungerade bättre för någon plats eller under vissa delar av året.

Marknadsundersökning om markägarens val av skogspartner

The driving forces from the forest owners point-of-view was studied on a market where several buyers attend to procure round-wood. It was concluded that forest owners prefer personal contacts to other means of communication, but that it is essential that the initial contact is a personal letter on paper. Furthermore, although price is always important, long standing relations is asked for. The buying companies need skillful experienced buyers that can provide more than just quick closures of deals..

Skattningar i gallringsskog med hjälp av flygburen laserskanning : beräkningar med massaslutenhet

This master?s thesis is a remote sensing study of an area-based method used to detect forest in need of thinning by use of laser data and field samples. Only pine-dominated forest has been included in the study and height limits were set to match empirical restrictions. The study area was in the municipality of Älvsbyn (Latitude 65° 40´ N, Longitude 21° 00´ E), in northern Sweden.The Swedish authority Lantmäteriet is currently laser scanning most parts of Sweden, providing new opportunities and applications. The primary aim of the national laser scanning is to create a new elevation model, useful in consequence analysis of climate changes.

Skogsskötsel för att främja sociala och estetiska värden i ett friluftsområde i Trollhättans Stad

Over 80% of Sweden's population lives in urban areas, and half of the country's forest visits will thus be in urban woodlands. Social values ??- how the individual experiences the forest, and the impact of the forest visits on individual health and well-being, are pointing to the importance of managing the urban woodlands.When there comes to the cultivation of the urban woodlands there are usually many opinions to consider.This study aims to investigate the various opinions on the use and forestry in an urban recreation area in ??the City of Trollhättan. The study addresses both general and in four cases specific suggestions on management methods.Data was obtained from both quantitative and qualitative study through survey, interviews and discussions with the users of the recreation area.Trollhättan's goal with the recreation area is to make it accessible to local residents. The users are mainly influenced by the accessibility therefore clearings and thinnings are appreciated.

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.

Köparnas nöjdhet med sin fastighetsmäklare

The purpose with this exam project has been to explore how satisfied the buyers of forest land have been with their real estate broker through the transfer process. The respondents had the opportunity to rate a number of different questions around the current acquisition. A questionnaire with 19 acquisition-related questions was sent to 134 people. People who since 2008-01-01 until today, have acted as a buyer of forest land. 80 responses were achieved and the result shows that the majority of buyers have a high gathered satisfaction..

Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna

The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.

Samband mellan laserdata och fältdata

To make it easier for forestry planning the forest owners needs data which describe characteristics of the forest. Such data you usually get from some type of inventory. A relatively new technology which probably is getting more important in the future, is laser scanning because of lower costs. But because the laser technology is relatively new you need to compare it with conventional inventory technologies to get better understanding of the possibilities the laser technology gives. This work intends to estimate field measured characteristics of the forest from laser data with help of regression analysis and then see which of the field measured properties that best could be estimated and which laser variables that gave the best results. This study shows that heights has the best estimates, but biomass, diameter and volume also gives good estimates.

Fältskiktsvegetationen 30 år efter beståndsanläggning : effekter av olika nivå på skogsskötselintensitet

En landsomfattande försökserie anlades mellan 1984 - 1988 med 15 försöksblock i Sverige. Syftet var att studera den totala effekten på virkesproduktionen av tre olika intensiva skogsskötselalternativ. Inom varje block upprättades en extensiv behandling som innebar att ingen åtgärd efter avverkning vidtogs, en normal behandling som motsvarade markägarens normala skötselintensitet vid tiden när försöken anlades. Slutligen fanns en intensiv behandling där ambitionsnivån skulle vara högre än vad som kunde anses vara normalt. Mitt syfte var att studera hur fältskiktets täckningsgrad och artantal påverkats av de tre olika skogsskötselintensiteterna på de tre försöksblocken Bjurholm, Edefors och Harads i Norra Sverige. På dessa block inventerade jag markvegetationen med fokus på fältskiktet i månadsskiftet mellan Juni och Juli 2013.

Realisering av en modulär skogsmaskin - En skalmodell

Wood for commercial use is harvested from forests using forest machines like harvesters which folds, branches and cuts trees and forwarders which transports logs to a landing area for further transport to a processing facility. Future forest machines have to be much gentler to the machine operators and forest soil than today's machines. Hence new machine solutions must be developed and tested. A practical way is to develop a physical scale model which can be used as a test-bed to incorporate different types of solutions for suspensions, cabin damping, tires and tracks, crane and overall architecture. The aim of this project was to develop such a 1:5 scale model of a forest machine, named as ?Skogbil.A scaling strategy was employed to arrive at important scale dimensions and specifications ofSkogbil which would be comparable to the full scale model.

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