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458 Uppsatser om Retention trees - Sida 13 av 31
Skogsskötsel för att minimera stormfällning över järnväg :
The society of today is dependent of secure transports and deliveries of electrical power. Interruptions in different activities because of fallen trees cost a great deal of money in form of reparations and claimed damages for transport companies and electrical suppliers. Fallen trees along some railway sections are a severe problem. For instance, to repair the damages of the storm of week 5 year 2002, costed 2 800 000 SEK for the line region of Hässleholm. Today, the Banverket railroad company has no norms in general for how close to the railway the forest is allowed to grow.
Ruminants´production within agroforestry systems in rural Rwanda : production benefits and problems
Intercropping involving trees is called agroforestry and makes it possible to get higher production for every area unit. The trees can function as food, fodder, fuel, medicine; prevent mark erosion and much more. Agroforestry can also be combined with animal husbandry.
The aim of this study was to document the animal production systems used by rural small-scale farmers maintaining ruminants and using agroforestry in the northern province of Rwanda. The farmers using agroforestry is expected to have higher milk yield than average due to homegrown protein.
The method used during the study was semi-structural interviews with booth open and closed questions. In order to get in contact with farmers that matched the criteria; small-scaled rural farmers with ruminants and using agroforestry, the ?Vi Agroforestry Programme? (Vi-Life) in Kigali were contacted and the staff worked as supervisors, translators and contact with the farmers throughout the study.
During the study nine individual farmers, two cooperatives breeding sheep and one group interview were conducted.
Alnarps rehabiliteringsskog : ett gestalningsförslag
The understanding of the role of nature for rehabilitation of both physical and psychological
afflictions has greatly increased in the last few years. There?s a lot of science that describes
the healing effects of nature. The rehabilitation garden in Alnarp has contributed with very
positive results from the treatments of patients with burnout syndrome. In the first stages of
rehabilitation, the need for calm is very important and a demand-less and stress-free
environment is of essence.
Till synes orörd skog : naturvärden och kulturhistoria i Rekdalen under 400 år
Nature conservation has for a long time been founded on the assumption that high ecological values depend on low human impact. In Sweden this has led to forests with these characteristics being strictly protected from human influences. However, it is also known that historical land-use can enhance ecological values in forests. Mountainous forests in Sweden, which have not been affected by modern forestry, have for a long time been considered as untouched by people. However, forest history research has in recent years shown that even these areas have been used by people for a long period of time.
Härliga hagar och skrämmande skogar : om våra känslor för landskapet och vad de beror på
Do our imaginations of real landscapes get affected by works of art such as paintings, myths and literature? They often give very colourful descriptions in words as well as pictures. Do they actually change our feelings for the landscapes we are in and carry around as images inside?
Close your eyes and take a few deep breaths. Imagine that you are leaning against a wooden fence a mild summer evening.
Är bor nödvändigt vid skogsgödsling i Sverige?
This thesis has been made on behalf of SCA Skog AB to assess the need of boron in Swedishforest fertilization. Boron has been added to Swedish forest fertilizers since the beginning of the1980s. This makes the fertilizers more expensive and therefore has the necessity of boron inSwedish forest fertilization been raised.The Swedish bedrock generally contains small amounts of boron. The boron in the bedrock istightly bound to the mineral tourmaline and mostly unavailable for plants. This leads to that thecontribution of boron to the soil from weathering is very low besides soils with marinesediments.
Lönsamhetskalkyl för produktion av gran på markavvattnad och askgödslad myrmark
In Sweden there are about 4 million hectares of bare peat (mire). This land has great potential to be transformed into productive forest land, provided drainage is carried out and, in some cases, even fertilization with ashes. Drainage of mires is necessary because the high groundwater table prevents trees from growing due to reduced oxygen availability. Some of the key nutrients that trees need to grow appear in too small quantities in mires, especially potassium (K) and phosphorus (P). Ash from the combustion of biomass contains these elements and is therefore suitable as a fertilizer.
Påverkan från den förväntade klimatförändringen på tillväxten i norra Sveriges skogar : En litteraturanalys
This is a literature review of how the climate change affects the forest growth innorthern Sweden. The temperature will rise about 5 °C with the largest increase in thewinter season (December - February) and the CO2level in the atmosphere is expected tobe doubled. Precipitation patterns will change and increase with 25-35 % and theprecipitation will be in form of rain rather than snow. Today the forests in northernSweden are entirely dominated by coniferous stands. This may shift with the climatechange and results in a larger number of deciduous trees, preferably birch will becomestronger and grow better and faster.
Insect communities inhabiting Inonotus radiatus growing on Alnus glutinosa trees at northern and southern shores of boreal lakes
This is a study of the insect community associated to the wood-decaying fungus Inonotus radiatus found on Alnus glutinosa trees growing in riparian forests at the northern and southern shores of boreal lakes in the province Uppland. Little is known about this particular bracket fungus and its inhabitants. Insects were reared out at the laboratory from samples of fruiting bodies of the fungus taken at five lakes. During the fieldwork in 2009, data about several environmental variables was also taken. After the rearing period, these variables and their effects over the insects were analyzed.
Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna
In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time.
The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.
Växter vid havet :
Detta examensarbete behandlar växter som trivs vid havet. Arbetet baseras på frågan vilka växter som tål ett vindpinat och utsatt läge?
Arbetet beskriver vad man skall tänka på när man börjar planera en trädgård vid havet. I arbetet har jag tagit upp vilka träd och perenner som man kan använda sig av när man skall skapa en trädgård vid havet.
Syftet med arbetet är att man skall kunna använda sig av mitt arbete när man åker till plantskolan för att inhandla växter.
Utveckling av en diameterklassmodell för grandominerade bestånd i Sverige :
Growth models are very useful tools for forestry to predict growth and yield. With growth models and optimising tools you can manage forest stands in a way that maximize benefit and income. There are three major types of growth models. Stand models; stage structured models and single-tree models. The most advanced models give the most accurate forecasts.
Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project
The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations.
The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.
Utvärdering av en subjektiv metod för att skatta mängden trädbiomassa längs vägkanter :
Forest biomass is becoming an increasingly important source of renewable energy, and thereby the demand is increasing. There is currently 213 000 km of forest roads in Sweden that could be suitable for biomass harvesting. Harvest of biomass along forest roads both provides biomass and maintains the quality of the roads. Currently, the volume of biomass along roads can only be assessed post harvest, chipping and industry deliverance.
As the decision of whether or not to harvest should preferably be based on more than experience, the TJ-method has been proposed. The TJ-method is a subjective method to quickly determine the dry matter quantity with the assessment being conducted from the roadside.
Rumslig fördelning av grov gammal tall i Uppsala stad med tallticka som indikator på höga naturvärden :
Fragmentation and reduction of forest area is a threat for many forest species and their habitat. Deficiencies in forest quality, such as lack of dead wood and old trees, are one explanation of the threat. The most important action to prevent the continued loss of forest types is to protect forest, but also to restore and to create areas that not previously had high nature values. Hence one of the key strategic roles for Fritid- och Naturkontoret, Uppsala municipality, is to monitor biodiversity in the context of urban planning.
The majority of the Uppsala municipality residents live in urban areas and most of them spend some of their spare time in natural areas in cities and their immediate surroundings. Exploitation in and around Uppsala is high, but it is important that there is enough nature close to houses to meet the residents? needs of recreation.