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912 Uppsatser om Tree species - Sida 17 av 61
En studie av viltets påverkan på Skogssällskapets fastighet i Selesjö
This degree project investigates how elk, roe deer, red deer and fallow deer can affect an estate in Östergötland. The inventories performed within this project, were completed on an estate in Selesjö, northern Östergötland. This property is used to demonstrate wildlife management.
The methods used in this study were originally developed for areas larger than individual properties. Three inventories were completed in the study. These included the recording of the number of droppings and the amount of eaten pasturage, as well as the level of damage on young trees.
Gäddan & fisket i Ringsjöholm : en osteologisk metodstudie i säsong & bevarande
This paper presents the results from an osteological method study of the Ringsjöholm fishbone material. Ringsjöholm is located in Scania, southern Sweden and is 14C dated to 5960-5200 B.P. The aim of this paper is to critically analyse methods used on fish bone material in estimations of season. Three different approaches were used to estimate the fishing season at the Ringsjöholm settlement; 1) identified species, 2) size estimations of the pike based on Enghoffs (1994-95) regression formulae of os dentale, and 3) growth rings of the pike vertebrae.The identified species and the size estimations of the pike points to the fishing being active both during spring and summer. Growth rings analysis of the pike vertebrae didn?t give any quantitative results because of fragmentation.
Artificiella EkosystemSom Artificiell Intelligens I Actionrollspel : En jämförelse av algoritmer och deras anpassning till realtids-spel
Artificiella ekosystem är en tillämpning av artificiell intelligens som har funnits länge. Användningsområden för artificiella ekosystem innefattar främst biologiska simulationer men även andra typer av simulationer förekommer. Genom att simulera individuella djur blir den artificiella intelligensens uppgift att styra djurens beslut utifrån dess individuella förutsättningar och kamp för överlevnad. Detta arbete behandlar frågeställningen vilken beslutsalgoritm som är bäst lämpad att för att använda till ett artificiellt ekosystem i ett spel. Två beslutsalgoritmer jämförs, en dynamisk som bygger på maskin inlärning och en statisk som inte är kapabel att lära eller minnas.
Bibaggar i Halländska grustäkter
This report is a result of a first survey of Halland?s gravel pits as an assignment from the County Administrative Board of Halland. The focus has been on Apalus bimaculatus, since the Swedish Environmental Protection Agency are creating a restoration program as it is red listed as Near Threatened. The purpose was also to get an overview of the pits since the County Administrative Board wants to continue this project. Apalus bimaculatus is easy to overlook since it is a short-lived beetle and it lives early in the spring.
Vilken effekt har lärkrutor på ogräsfloran vid ekologisk höstveteodling? :
This study forms part of the R&D project "Improved survival of bird chicks in organic fields" managed by the Rural Economy & Agricultural society in Uppsala. The skylark (Alauda arvensis) is a species that has decreased drastically in Sweden as a consequence of more intensive cropping.
Studies in England have shown that skylark reproduction can be greatly improved within
conventional fields, at a low cost, by establishing patches of bare ground (skylark plots).
Within conventional farming, herbicides can be used in case a weed problem arises due to
implementation of these skylark plots, whereas this is not allowed in organic farming. This study examined the effects of skylark plots on the weed culture in organic autumn-sown (winter) cereals and whether weeds might cause long-term problems to farmers.
The study was conducted in two parts; a field study and a review of the literature regarding the weeds observed. The field study was carried out in 2007 during three weeks in June and three weeks in July, on eleven organic fields with winter cereal in the vicinity of Uppsala.
Klövviltets nyttjande av foderraps på viltåker och betespåverkan på angränsande skog
Today we have more game species than ever before in our landscape, both regarding number of species and number of individuals. The increasing number of wild species is an increase in game recourse for the countryside. The increase of game species, however, has negative effects on forests and agriculture land. The negative effects for forestry are damages on economic important trees, due to losses in production and quality. However there are ways to decrease the damage on valuable and important trees.
Effekter av upphörd hävd i Lurö skärgård : Har diversiteten av kärlväxtarter förändrats?
One of the main reasons for the massive loss in plant species diversity is the fragmentation of habitats. In Europe, open pastures and meadows are the habitats going through the most changes during the 20th century, according to the agricultural changes. In this study vascular plants were invented at five different islands in the Lurö archipelago, Vänern, Sweden. The aim of the study was to sort out whether the diversity of plants has gone through any changes in abandoned managed grasslands compared to continuous managed grasslands. The aim was also to study if a change in the landscape has made any differences for the species development or decline.
Threats and opportunities for the survival of the Yangtze finless porpoise
The Yangtze finless porpoise (Neophocaena phocaenoides asiaorientalis), is a small freshwater cetacean which has recently fallen dramatically in number. It is an endemic species for the Yangtze River and unless drastic action is taken, it risks the same fate as the now functionally extinct Yangtze river dolphin (Lipotes vexillifer). Threats to the porpoise are diverse but they have in common that they are caused by man. Development of the river has been made to supply a growing human population with food, hydropower, and to reduce the risk of flooding. These changes have resulted in a degraded habitat for the porpoise.
Rissepareringens effekter på viltets nyttjandegrad av GROT
Successful forest regeneration is a prerequisite for sustainable forest management. Therefore, it is important to prevent browsing damage on the commercially important Tree species Scots pine. In this study I have tested a new alternative way to increase the available amount of forage and increase the use of these resources by especially moose. The method is based on a slash treatment at harvest, where the accessibility of slash as forage is increased during final felling or commercial thinning by gathering the slash and putting the Scots pine slash on top of the slash piles. This study has compared the availability of forage, the amount of browsed biomass and the number of fecal pellet groups between conventional and slash treated stands after final felling and commercial thinning in southern Sweden.
Vad styr sortimentet hos svenska perennaodlare? : en studie baserad på sju företag i Sydsverige
The purpose of this study is to clarify the most important factors that affect Swedish perennial growers when designing their assortment. The study describes how herbaceous perennials are produced in Sweden today and try to give an answer to the question how growing method and choice of assortment are affecting the possibilities of Swedish producers to compete on the market.
Seven perennial growers in the southern and western parts of Sweden have been interviewed about their production methods and on what basis they design the assortment of perennials. During the interviews five factors seem to be the most important when the growers choose which species to grow ? profitability, the characteristics of the species, the sales channel/customer, the growing environment/growing facility and the grower?s interest and knowledge. It is often a combination of these five factors deciding if a cultivar will be grown or not.
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Skogsbolagens syn på vindskadeförebyggande åtgärder efter stormen Dagmar
On the night of the 26th December 2011, large parts of southern Norrland were struck by the storm ?Dagmar? that caused serious damage to the forests. In the past 10 years wind damage has become a hot topic after several major storms. Forest companies own 25% of the Swedish forest and thus influenced largely by wind damage. The main purpose of this study was to examine whether forest companies attitude towards preventive wind damage actions were changed after the storm ?Dagmar?.
The result was developed by doing interviews with two forestry companies.
Större svartbagge Upis ceramboides i norra Hälsingland : förekomst, substratkrav och effekter av skogsbrukets naturvårdsåtgärder
Many wood living insects are considered threatened by modern forestry due to the reduction in amount of dead wood. During the last decade various methods have been used to enhance the quantity of dead wood in managed forests. However little is known how and if these methods are aiding saproxylic insects. The threatened tenebrionid beetle, Upis ceramboides, is already extinct in southern Sweden. It develops in white rotted dead birch (Betula spp) and requires sun-exposed sites.
Trädföryngring i låga gropar uppkomna vid brand i boreal naturskog :
This study was conducted in the "Kåtaberget" forest reserve in Västerbotten in the summer of 1999. In the summer of 1995, a prescribed burning was performed in the reserve. In some places where coarse dry woody debris (logs and stumps) was present, the fire consumed the wood, as well as parts of the humus layer, creating deep-burned patches. The low intensity ground fire also created dead woody debris by burning off living trees with open fire scars, as well as standing dead trees.
In this study, the post-fire tree seedling establishment was examined, with special attention given to the former presence of woody debris. The study also includes a survey of the areal extent of deep-burned patches, as well as an examination of tree seedling establishment in these patches, compared to other burnt ground.
Digitala fotogrammetriska arbetsstationer för skoglig flygbildstolkning :
SCA Skog has taken the initiative to this Master?s thesis. Today SCA Skog has a great need to update their informtion on young forest stands across large areas. Traditional field inventory methods for updating stand databases are expensive and time consuming. However, the inventory could be made more efficient if stand boundaries and stand characteristics are derived from aerial photographs.
Fodder to ruminants within agroforestry systems in Rwanda - species and management
Rwanda is one of the poorest countries in the world and about 70-80 % of the population lives in rural areas. The land is strongly affected by land erosion which makes it difficult for the agriculture and food production. Agroforestry is a system where tree plantation is combined with livestock- and crop production. The system provides soil fertilization and binds the soil together. Some of the trees used in agroforestry systems are also used as fodder.