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935 Uppsatser om Alder wetland forest - Sida 34 av 63
Stormskador i stickvägsgallrade bestånd i sydvästra Sverige :
A storm in January 2005 felled 75 millions cubic metres of forest in South Sweden. Previous studies of wind damage in thinned stands indicated the importance of early thinnings. The risks of wind throw increased by increasing age and height of the stands. Previous studies also indicated increasing risk of wind throw along the strip roads. The aim of the present study was to investigate wind damage in Norway spruce stands in South Sweden in relation to time of the first thinning and different pattern of strip roads (width, length and direction).
Vart är naturen i skärgården på väg? : skogshistoria på Ängsön-Marskär i Stockholms södra skärgård
The following thesis is a study of the forest history on the island of Ängsön-Marskär concentrating on the last three hundred years. The island is located in the administrative province of Stockholm, the local community of Haninge and it is situated approximately seven kilometres east of the island Ornö in the south of the Stockholm archipelago. The questions this thesis attempts to answer are: How where the natural resources on Ängsön-Marskär used through the centuries? How has the state of the forests developed since the 16th century? How will the nature develop onwards? The thesis is based on archival sources for Ängsön-Marskär and the surrounding areas. A field study was conducted where the entire island was investigated using an objective forest inventory method.
The first map material existing over Ängsön-Marskär is from the year 1711.
Kvalitetssäkring av markberednings- och planteringsuppföljning hos SCA Skog AB Jämtlands skogsförvaltning :
Quality assurance means to systematically work for better understanding of the customers needs, demands and expectations. The goal for this study was to investigate how quality can be assured in the job follow up that is made by forestry contractors after soil scarification and planting. The study consisted of a description over the current follow up process at SCA forest AB Jämtlands forest administration, analysis of current follow up situation and an investigation of follow up process made by contractors in other line of business.
The first step was a statistical comparison where the own follow up made by contractors were compared with follow up made by SCA them selves over 100 stands. Two soil scarification contractors and two planting contractors carried out the silvicultural measures. The results showed that significant differences between a number of quality factors measured, for example number of approved plants or approved scarification points, average score on stand and number of totally planted plants.
Överlevnad, tillväxt och skador i planteringar av sitkagran (Picea sitchensis) efter stormen Gudrun
Sitka spruce (Picea sitchensis (Bong.) Carr) is just like Norway spruce (Picea abies) a species in thegenus picea. The natural range of Sitka spruce is a narrow strip along the west coast of North America. Itis the most coastal of all picea species, and very dependent on the mild and humid climate along thepacific coast.Sitka spruce has been grown a long time in the countries around the North Sea, particularly in GreatBritain where it currently is the most important species in British forestry. Sitka spruce has not beenplanted in Swedish forests to any large extent before the storm Gudrun in 2005. Several studies indicatethat the production of wood biomass is higher for Sitka spruce compared to Norway spruce.
Våtmarker i urbana miljöer : växtgestaltning och planering
The practice of landscape architectural involves forming the space in our cities and suburbs, as well as the landscape surrounding. The need of exploiting green environment leads up to, among other issues, flood problem during heavy rain and overfed water environments. The problem is partially caused by the shortage of knowledge, how the environment is responding of the innovations made by the city- urban planning and how to get sustainability.
Research and knowledge how to take care of our environment, in a natural way, is increasing. The object of the thesis is to propose control and balance in urban wetlands, and discuss the difference a plant design can do.
The thesis deals with discourses in the field of landscape architecture, biological diversity, dam construction, limnology, planting design and management, pollution of the environment and urban design practice.
Behandling av konfliktbestånd - problem och möjligheter :
Overdue cleanings have for a long time been an important topic of discussion within the forestry sector. When stands that have not been pre-commercially thinned are reaching the level of commercial thinning, many problems occur in terms of decision-making and economical outcomes. These types of stands are commonly known as conflict-stands.
The work was carried out partly as an interview survey towards representatives from the forest sector and the energy sector, partly as a case study of conflict-stands situated in Böksholm, north of Växjö and in Tönnersjö east of Halmstad. The criteria for the studied stands were that they had to be dominated by Norway spruce and be in a severe status of ?conflict?.
The aim of the interview was to get an overview of the situation today, and also analyse trends in terms of conflict stands.
Fjällfåglar : En jämförande studie från dal till topp i ett nordligt och sydligt svenskt fjäll
Title: Mountain birds ? a comparative study from valley to mountaintop in a northern and southern Swedish fjeld Author: Kristian Zackrisson Abstract Main aim in this study was to increase the knowledge about birds in the Swedish mountain area. Three questions were asked: 1) Which bird species can be found during the breeding season along a low mountain slope from a forested valley to a mountaintop with bare mountain environment? 2) Do the number of species and individuals differ in different elevation zones? 3) Is the composition of bird species along a low mountain slope the same in the Kebnekaise mountains inLaplandand the Grövelsjön mountains in Dalarna? Bird census in two study sites located in the Kebnekaise mountains and the Grövelsjön mountains and subsequent analysis of the results from the bird census was the main parts in this study. Totally 20 bird species were found along a low mountain slope in the Kebnekaise mountains.
AHA in northern Sweden ? a case study : conservation values of deciduous trees based on saproxylic insects
AHA is a Swedish abbreviation of "reveal threatened park and avenue trees" and is a method to assess the conservation value of individual trees, mainly in the park environments but also in natural stands. This method has previously only been practiced in southern Sweden (Sörensson 2008). To see if this method could provide satisfactory results in northern Sweden, I have studied it in areas around the Umeå River. This was done by studying the relationship between trees with different classifications of conservation value (as classed by the AHA method) and their content of species (species richness and abundance). Insects were collected using trunk window traps in a period of 13 weeks during the summer of 2014.
Indirekta effekter på marklavars abundans och diversitet vid ökad kvävehalt i marken : en jämförelse mellan opåverkad och lågintensivt brukad mark
Lichens are adapted to bright and sparse forests on oligotrophic ground. Due to a slow growth rate and high light demand lichens will suffer from competition in eutrophic environments. Therefore, lichens have disappeared from managed forests where the forest industry has increased the productivity. A reduced abundance of lichens will affect both biodiversity of the forest and the reindeer winter graze lands. It is important to understand how and for how long fertilization affects the abundance and diversity of lichens in order to protect lichen rich ecosystems.
We have registered the biomass and number of lichen species in eight plots (four nitrogen rich and four nitrogen deficient) and compared fertilized Sami settlements with their oligotrophic surroundings in the nature reserves of Tjeggelvas.
Jordförvärvslagens ändring 2005 och dess påverkan vid skogsfastighetsköp : The amendment of Lad Acquisition Act 2005 and its influence on forest property purchase
Since the beginning of the 1900s Sweden has had laws and rules governing the ownership of agricultural and forest land. The foundations of the current Land Ownership Law, ?Jordförvärvslagen 1979:230(JFL)?, are from 1979. The most recent review and adaptation of the law occurred in 2005. Its main purpose is to prevent a passive ownership of land in Sweden and to ensure that the land is actively worked.
Större och mindre växtätares samexistens : Möjlig interaktion och effekt på lokal biodiversitet
The purpose of this report was to investigate to which extent local presence of large herbivore mammals (Alces alces, Cervus elaphus, Capreolus capreolus, Dama dama and Sus scrofa) covaries with small rodents (Myodes glaerolus, Apodemus flavicollis and Apodemus sylvaticus? The hypothesis was that high abundance of wild ungulates would inhibit the density of small forest rodents. The data was collected during field work within FoMA (Environmental Monitoring Assessment)/SLU (Swedish University of Agricultural Science). The Ungulate dropping inventory and rodent trappings, which is the base in this report, where performed 2012 ? 2014 in Gnesta/Nyköping municipalities (G/N) with a relatively high density of wild ungulates and Vetlanda/Växjö municipalities (V/V) with relatively lower wild ungulate density.
Användarcentrerad utveckling av mobilt IT-stöd
This exam paper has been a collaboration between the writers and SYSteam Utvecklingspartner in Huskvarna. The assignment was about finding a need for a mobile application, making a requirement specification document with design documents and parallel to this constructing a prototype. The assignment is summarized in the following questions:? How can companies in the forest industry benefit from mobile information technology?? How can a user centered perspective be used in the process of making the requirement specification document and the design documents?? How do guidelines for usability apply to a mobile application?Three visits to companies in the forest industry were made to find a need for mobile information technology solutions. After a small analysis of the different companies? problems and conditions the decision was to use Tenhults Impregneringsverk AB in the case study.We used the FA/SIM method in our job of finding the organization needs for change and the principles of User Centered Design in the work of constructing a prototype.The result of our work is a requirement specification with design documents and a prototype.
Varför slutar markberedningsförare?
The purpose of this study is to seek answers to an ongoing problem in the forest sector; why scarifying operators quit their job. Scarification quality is crucial for successful reforestation after clear felling. It is therefore important to keep good operators working in the business.
To collect the desirable information interviews were made both with contractors who are working and operators who have stopped working with scarifying. The conclusion one can draw from this report is that the scarifying operator job needs improvement in multiple areas. The former operators are mostly dissatisfied with the stress, low wages and negative physical effects that this work brings..
Buskröjning längs skogsbilvägar : en produktivitetsstudie av två kättingslagor
To regularly remove woody vegetation along the roadside of forest roads is an important part of the road maintenance, since the vegetation binds moisture in the road side and, thus, the removal makes the road drying faster with results in improved bearing capacity. Vegetation removal also makes it easier to upgrade the road by material recycling from the ditch and, moreover, the visibility along the road is maintained.The aim of the study was to evaluate what type of chain flail is the best and most cost-effective for removal of different kind of woody vegetation along forest roadsides.Time studies were made on two chain flails when removing woody vegetation in three different classes; easy-, middle- and heavy shrub removal. The studied flails were one light and rather simple flail named Optimal M160 and a heavier and more advanced flail named Slagkraft H210. The removal was made according to Holmen Skogs? specification and the quality of the cleaning was measured by objective belt inventory.The productivity was higher with the heavy flail within all cleaning classes.
En studie av sedimenttransport, död ved och kantzoner längs två vattendrag i Kilsbergen - från skog till slätt :
Headwater streams are affected by anthropogenic impacts at multiple scales.
One aspect of human impact is sediment transport associated to the
abundance of stream structures as large woody debris and the composition
of the riparian zone from forest to agricultural landscapes.
Riparian buffer zones and stream structures like dead wood are considered
as generally important structures for protection against an increasing
amount of sediment particles in the water. Hence, in this study these
structures were quantified in thirty different stream segments on land and in
the water.
To measure the transport of sediment Whitlock-Vibert boxes were used in
three different types of landscapes; forest, transition and fields. The boxes
were left in the stream segments for three months, the taken up and dried
and weighed. The results showed that the transition-land in Frösvidalsån
had the highest sediment transport. The second highest transport of
sediment was in Blackstaån at the fields.